Radical Neck Dissection 

Updated: Sep 08, 2017
Author: Antonio Riera March, MD, FACS; Chief Editor: Arlen D Meyers, MD, MBA 

Overview

Background

Metastatic neck disease is the most important factor in the spread of head and neck squamous cell carcinoma from primary sites. The primary sites most commonly involved in the spread of this carcinoma are the mucosal areas of the upper aerodigestive tract, particularly the larynx, oropharynx, hypopharynx, and oral cavity.

Lymph node metastasis reduces the survival rate of patients with squamous cell carcinoma by half. The survival rate is less than 5% in patients who previously underwent surgery and have a recurrent metastasis in the neck. Therefore, the control of the neck is one of the most important aspects in the successful management of these particular tumors.

Radical neck dissection is an operation that was created in 1906 to solve the problem of metastatic neck disease. It is a well-designed operation that is relatively easy for the trained head and neck surgeon to learn and to perform. Classic radical neck dissection is still the criterion standard for surgical control of a neck metastasis.

See the image below.

Patient in supine position and head turned to the Patient in supine position and head turned to the right side. Radical Left Neck Dissection completed: The classical radical neck dissection encompasses the lymphatic nodes in levels I-V. View of the surgical wound after removal of the operative monoblock specimen. S = Superior. I = Inferior. M = Medial. L = Lateral. (1) Anterior and posterior bellies of the digastric muscle. (2) Carotid artery and vagus nerve. (3) Anterior cervical nerve root. (4) Phrenic nerve. (5) Brachial plexus. (6) Internal jugular vein, inferior aspect, cut and ligated. (7) Anterior scalene muscle. (8) External jugular vein, inferior aspect, cut and ligated. (9) Hypoglossal nerve. (10) Sternocleidomastoid muscle, superior aspect, cut.

In the last 3 decades, progressive advances have occurred in the understanding of cervical fascial planes, lymphatic drainage patterns, preoperative staging, and extracapsular spread. A concern to maximize control and to minimize morbidity has prompted modifications to the classic neck dissection. One such modification is the preservation of 1 or more nonlymphatic structures (eg, spinal accessory nerve, internal jugular vein, sternocleidomastoid muscle). Further observations have indicated that the pattern of nodal disease depends on the primary site. Therefore, these findings led to another neck dissection modification, which is the selective preservation of 1 or several lymph node groups.

History of the Procedure

In 1906, George W. Crile was the first person to describe radical neck dissection, which encompasses the surgical removal of neck metastasis contained between the superficial and deep fascial layers of the neck. Hayes Martin routinely used radical neck dissection for the management of neck metastasis in the 1950s. The main goal of this procedure was to remove, en bloc, the entire ipsilateral lymphatic structures from the mandible superiorly to the clavicle inferiorly and from the infrahyoid muscles to the anterior border of the trapezius.

The resection included the spinal accessory nerve, the internal jugular vein, the sternocleidomastoid muscle, and the submandibular gland. The anatomic structures that remained were the carotid arteries, vagus nerve, hypoglossal nerve, brachial plexus, and phrenic nerve. This operation and its oncologic concept are still valid; however, the procedure has been modified to decrease its morbidity but to maintain its oncologic efficacy. In the 1960s, O. Suarez and E. Bocca independently described a more conservative operation that involved removing all the lymph nodes but sparing the spinal accessory nerve, sternocleidomastoid muscle, and internal jugular vein. Finally, further procedures were designed to remove only selected regional lymph groups involved, depending on the primary site of origin.

Multiple modifications to the radical neck operation brought about new terms to describe such changes, and the terms for the same modification varied from author to author. Many cases of unclear terminology created confusion among clinicians from different geographical areas and institutions. Therefore, standardization was necessary. In 1991, the American Academy of Otolaryngology-Head and Neck Surgery published an official report that standardized the terminology for the different types of neck dissection.

The report was updated and published in 2002, with only a few changes, which dealt with the application of various types of selective neck dissection procedures for oral cavity cancer, pharyngeal and laryngeal cancer, thyroid cancer, and cutaneous malignancies. In addition, 2 new neck sublevels, Va and Vb, were added for a total of 6 neck levels and 6 neck sublevels. (The 1991 version of the report listed only 4 neck sublevels.) With the exception of the 2 added neck sublevels, the terminology in the updated report is the same as that of the 1991 version. The authors refer the reader to the article "Neck Dissection Classification Update, Revisions Proposed by the American Head and Neck Society and the American Academy of Otolaryngology-Head and Neck Surgery"[1, 2]

Modifications to the radical neck dissection include the following:

  • Type I: The spinal accessory nerve is preserved.

  • Type II: The spinal accessory nerve and the internal jugular vein are preserved.

  • Type III: The spinal accessory nerve, the internal jugular vein, and the sternocleidomastoid muscle are preserved.

  • Extended radical neck dissection: The lymph node groups and/or additional structures not included in the classic neck dissection are resected.

The 2011 publication by Ferlito[3] states the rationale for a new neck dissection classification/nomenclature and uses the symbol “ND” for neck dissection. The levels and sublevels of nodes removed are identified by Roman numerals (I through VI) and the nonlymphatic structures removed are identified by abbreviations (SCM, IJC, CNXI, etc.). The purpose of this new classification is the unification of terminology used in neck dissection around the world.

Problem

Lymphatic metastasis is the most important mechanism of spread in head and neck squamous cell carcinoma. The risk of lymph node involvement by metastasis varies depending on the site of origin, size of primary tumor, histologic grade of the primary tumor, perineural invasion, perivascular invasion, and extracapsular spread. Management of the neck lymph nodes is an integral part of treatment of head and neck cancer. Conversely, no single standardized treatment for cervical metastasis exists.

The indications and type of neck dissection to be performed in the N+ neck and management of the N0 neck remain controversial. Management is based on personal experience and retrospective studies. Radical neck dissection was the first attempt at adequately treating metastatic cervical lymphatic spread. The classic operation was subsequently modified several times to decrease morbidity without decreasing oncologic control. The 2 procedures in common use today are the modified radical and the selective neck dissections.

Epidemiology

Frequency

The incidence of metastatic disease for the upper aerodigestive tract varies widely, from 1-85%, depending on the site, size, and differentiation of the tumor. The rate of ipsilateral metastatic disease in patients with stage T3-T4 squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx, or supraglottis is approximately 50%. The rate of bilateral or contralateral metastatic disease in these patients varies from 2-35%.

Nasopharyngeal carcinoma appears as a neck mass in approximately 50% of patients. Metastatic neck disease in thyroid gland tumors occurs as follows: papillary, 55%; medullary, 50%; and follicular, 25%.

Tumors localized in the oral cavity, oral mucosa, oropharynx, hypopharynx, and supraglottis have a higher incidence of metastasis than tumors of the superior gingiva, hard palate, and glottis. Many other factors contribute to the risk of neck metastasis, including the following:

  • Anterior portions of the oral cavity are associated with smaller risk of neck metastasis than posterior portions.

  • Young patients with oral carcinoma have a higher risk of developing nodal metastasis than older patients.

  • Risk of neck involvement by metastasis increases with an increase in tumor size.

  • Perineural and perivascular invasion are associated with a high risk of nodal metastasis. The extracapsular spread of the nodes also carries a high probability for lymphatic spread.

  • Poorly differentiated tumors are associated with a higher risk of neck metastasis than well-differentiated tumors.

Etiology

Radical neck dissection is performed for the surgical control of metastatic neck disease in patients with squamous cell carcinomas of the upper aerodigestive tract, salivary gland tumors, and skin cancer of the head and neck (including melanomas). Radical neck dissection is also indicated for the surgical control of metastatic carcinoma to the neck when the nasopharynx and thyroid are the primary sites.

Pathophysiology

Metastasis occurs frequently in malignancies. The tumor grows at the primary site by dysfunction in cellular proliferation, differentiation, and death. Mutations due to chemical carcinogens, radiation, or viruses may cause activation of oncogenes by normal cells, multiple genetic mutations, activation of proto-oncogenes, and/or inactivation of tumor suppressor genes, which may cause alterations in growth control.

Tumor cells move through the basement lamina of the epithelium and the stroma into the lymphatic and vascular channels (ie, the tumor progresses from carcinoma in situ to microinvasive tumor). This process is related to the production of cytokines, enzymes, and growth factors that destroy the basement membrane and create abnormal angiogenesis, which, in turn, triggers neovascularization and growth. The tumor spreads into the regional lymph nodes by lymphatic and vascular channel invasion and may seed other parenchymal sites if tumor invasion is not controlled at the lymphatic level. The usual sites of secondary spread include the lungs, liver, bone, brain, and adjacent skin, as well as other sites, depending on the tumor histology.

Presentation

Most patients present with a unilateral or bilateral neck mass. Usually, the patient is already aware of the primary lesion, or it is found during physical examination of the upper aerodigestive tract.

In 15% of patients, a metastatic neck mass is present without an obvious primary lesion. In this situation, making every effort to identify the primary lesion is difficult. These patients require a careful evaluation of all mucous membranes of the upper aerodigestive tract with blind biopsies and an ipsilateral tonsillectomy.

Nodal classification

The most important prognostic factor in patients with squamous cell carcinoma of the head and neck is the status of the neck nodes. The extent of cervical lymphadenopathy constitutes the N portion of the tumor, node, metastases (TNM) classification by the American Joint Committee on Cancer.[4] This committee assigns N1-N3 ratings to different degrees of cervical adenopathy, with subgroupings of a, b, and c for certain stages. The nodal classification is as follows:

  • NX - Cervical neck nodes not assessable

  • N0 - No cervical node metastasis

  • N1 - Single ipsilateral node metastasis, 3 cm or less in diameter

  • N2a - Single ipsilateral node, more than 3 cm but not more than 6 cm in diameter

  • N2b - Multiple positive ipsilateral nodes no more than 6 cm in diameter

  • N2c - Bilateral or contralateral positive nodes no more than 6 cm in diameter

  • N3 - Massive adenopathy more than 6 cm in diameter

For further details see the Quick Reference Guide to TNM Staging of Head and Neck Cancer and Neck Dissection Classifcation from the American Academy of Otolaryngology–Head and Neck Surgery.[2]

Palpation

The accuracy of nodal status relates to the physician's ability to detect cervical adenopathy. Palpation is the technique used most in the detection of neck metastasis. Although palpation is inexpensive and easy to perform, it is not totally reliable.

Sensitivity and specificity of the neck examination by palpation range from 60-70%. A short obese neck and/or previous radiation or surgery makes the physical examination more difficult. Therefore, negative palpation findings of the neck still indicate a risk for occult metastatic disease. This risk increases according to the site, size, and particular characteristics of the primary lesion.

Imaging

Imaging is an integral part of clinical diagnosis and staging, and the results are helpful in deciding treatment. Among these techniques are computed tomography (CT) scanning, magnetic resonance imaging (MRI), ultrasonography, and ultrasound-guided aspiration cytology.

CT reveals metastatic adenopathy by central necrosis and extracapsular spread by enhancement of the nodal capsule. MRI is less precise than CT scan in identifying tumor necrosis and extracapsular spread, but MRI is better in assessing enlarged lymph nodes that do not necessarily represent metastasis. Both techniques cannot detect lymph nodes smaller than 1 cm. which, on occasion, independently of the size, are involved in metastasis. Ultrasound-guided aspiration cytology has a higher specificity than CT and MRI in analyzing lymph nodes, particularly in smaller nodes of less than 10 mm. However, the yield of this technique is directly related to the experience of the ultrasonographer and the pathologist.

Positron emission tomography (PET) has recently been used to assist in the diagnosis of lymph node metastasis. PET provides information about the metabolic activity of the tissues. Tissues with squamous cell carcinoma cells capture [18 F] fluoro-2-deoxy-D-glucose (FDG) at increased rates compared with normal tissues. Therefore, a minimal amount of tumor tissue must be present for the finding to be positive. Thus, precision of PET is limited to about 5 mm.[5]

Recent literature has demonstrated the higher sensitivity and specificity of the FDG-PET compared with ultrasonography, CT scan, and MRI in the assessment of metastatic staging of neck carcinomas. This finding could signify a positive role for PET in the identification of metastatic disease in patients with a clinically N0 neck. PET findings could provide early diagnosis of recurrent head and neck cancer, as well as indicate the status of the neck after chemoradiotherapy.

New challenges have occurred in the last 15 years in the selection of candidates for neck dissection who were treated initially with organ preservation treatment protocols and who may have persistence of neck disease after the nonoperative management. This group of patients can benefit greatly from the routine use of posttreatment PET/CT during their assessment for subsequent surgical management of the neck. PET and PET/CT are discussed further in the Workup section.

Histologic examination

Finally, the criterion standard for the detection of lymph node metastasis in the neck is the careful histologic examination of all nodes by the pathologist after the neck dissection is completed. Detection and accurate staging of neck metastasis are extremely important because staging has major implications for prognosis and treatment.

The most widely accepted terminology to define the regions of involvement of the cervical lymph node groups is the one developed originally by head and neck surgeons at the Memorial Sloan-Kettering Hospital. The terminology is as follows:

  • Region/level I - Submental and submandibular nodes

    • Ia - Nodes in the submental triangle bound by the anterior belly of the digastric and the hyoid bone

    • Ib - Nodes in the triangle bound by the anterior and posterior bellies of the digastric and body of the mandible

  • Region/level II - Upper jugular lymph nodes, including the jugulodigastric nodes

    • IIa - Nodes in the region anterior to the spinal accessory nerve

    • IIb - Nodes in the region posterior to the spinal accessory nerve

  • Region/level III - Nodes from the carotid bifurcation to the omohyoid muscle

  • Region/level IV - Nodes of the lower jugular area that extend from the omohyoid to the clavicle

  • Region/level V - All lymph nodes within the posterior triangle of the neck

  • Region/level VI - Nodes in the anterior compartment group, including the lymph nodes that surround the midline structures of the neck (These nodes extend from the hyoid bone superiorly to the suprasternal notch inferiorly.)

The revisions proposed by the American Head and Neck Society and the American Academy of Otolaryngology Head and Neck Surgery Committee and published in 2002 recommended the use of 6 neck levels and 6 sublevels, which added 2 extra sublevels (a and b) at level V. The 6 sublevels are Ia (submental nodes), Ib (submandibular nodes), IIa and IIb (upper jugular nodes), Va (spinal accessory nodes), and Vb (transverse cervical and supraclavicular nodes).[2]

Indications

The use of radical neck dissection has decreased over the last 2 decades with the use of chemoradiation as a non-surgical option.[6] At present, the classical radical neck dissection represents less than 20% of all cervical dissections.[7]                                                  

Therefore, when oncologic principles are not compromised (ie, no gross evidence of extension to the spinal accessory nerve or the internal jugular vein), modified radical neck dissection is preferred. Furthermore, in selected patients with clinical neck metastasis, a selective neck dissection has been advocated in clinical trials. Therefore, in the case of positive neck metastasis, the option of Modified RND or Selective ND will remain a surgeon's judgment call, taking into consideration the intraoperative findings and the level of oncological experience. As a consequence, the indications for Modified RND and Selective Neck Disection are not well defined or standardized, and vary from surgeon to surgeon. A word of caution, never sacrifice surgical oncological principles for a less radical surgery.

In general terms, the present use of the classical radical and modified neck dissection applies to patients with advanced metastatic neck disease, including the following:

  • N3 neck disease.[8, 9]

  • Multiple positive neck nodes clinically present in an untreated patient (N2b, N2c), in particular in the proximity of the accessory nerve and posterior neck triangle.

  • One or more positive neck nodes clinically present with extracapsular extension involving the spinal accessory nerve and internal jugular vein.

  • Imaging studies and/or clinical evidence of extranodal disease.

  • Neck metastasis with involvement of the platysma muscle and cervical skin.

  • Recurrent or persistent metastatic disease is present after previous conservative neck dissection, irradiation, chemoradiation, or a combination thereof.

Radical neck dissection is effective in controlling a postirradiation cervical metastasis from a nasopharyngeal carcinoma if the primary site is under control.

Indications (usually an intraoperative assessment) for a modified radical neck dissection include the following:[10]

  • Modified radical neck dissection type I - A clinically positive lymph node metastasis that does not include the spinal accessory nerve

  • Modified radical neck dissection type II - Metastatic tumor mass that involves the sternocleidomastoid muscle but not the internal jugular vein or spinal accessory nerve

  • Modified radical neck dissection type III - Indicated to remove clinically positive lymph node metastasis that does not infiltrate the nonlymphatic structures

    • Modified radical neck dissection type III is also indicated for patients with a palpable metastasis caused by a differentiated carcinoma of the thyroid.

    • According to some authors, modified radical neck dissection type III is indicated in patients with squamous cell carcinoma and an N0 neck when the original tumor is in the larynx, hypopharynx, or both. Other authors prefer further modification by sparing the submandibular triangle nodes because of low risk of metastasis to those nodes.

Relevant Anatomy

A comprehension of the relevant neck anatomy is mandatory to understand how to perform an adequate radical neck dissection. From the surgical point of view, each side of the neck is divided into 2 cervical triangles.

Cervical neck triangles

The neck is divided into an anterior and a posterior cervical triangle.

The borders of the anterior cervical triangle are the inferior border of the mandible, the sternocleidomastoid muscle, and the midline of the neck.

The anterior cervical triangle is further subdivided into 4 smaller triangles: the submandibular triangle, submental triangle, muscular triangle, and carotid triangle. Understanding and identifying each of these areas guide the surgeon in performing a complete removal of the entire contents of the anterior cervical triangle.

The inferior border of the mandible and the 2 bellies of the digastric muscle delineate the submandibular triangle. The mylohyoid and hyoglossus muscles form the floor. Contents are the submandibular gland, lymphatic structures, anterior facial vein, and facial artery. The lingual nerve is above the muscular floor and below the deep layer of the deep cervical fascia.

The anterior belly of the digastric muscle, the hyoid bone, and the midline of the neck delineate the submental triangle. The mylohyoid muscle forms the floor of the submental triangle. It contains a few lymph nodes and small tributaries of the anterior jugular vein.

The omohyoid muscle in the anterior cervical triangle delineates the muscular triangle below and the carotid triangle above.

The posterior cervical triangle is also referred to as the lateral cervical triangle and is limited by the anterior margin of the trapezius muscle, the posterior border of the sternocleidomastoid muscle, and the middle third of the clavicle.

The posterior aspect of the omohyoid muscle further subdivides the posterior cervical triangle into 2 smaller triangles, the occipital triangle, which is located above the omohyoid muscle, and the supraclavicular triangle, which is located inferiorly to the muscle.

Cervical lymph nodes

The cervical lymph nodes are divided into superficial and deep chains.

Superficial lymph nodes are involved in a late stage of cancer; therefore, they have less oncologic importance.

Deep cervical lymph nodes receive drainage from areas of the oral cavity, pharynx, larynx, salivary glands, thyroid, and the skin of the head and neck. These deep cervical (superior, middle, inferior) lymph nodes accompany the internal jugular vein and its branches. Oncologically, the superior jugular nodes (ie, the group that is near the anterosuperior aspect of the accessory nerve) are crucial. They represent the most difficult area in the resection of the deep jugular nodes.

Cervical lymph nodes localized in the posterior triangle of the neck are classified into the upper, middle, and inferior cervical nodes. Posterior triangle nodes are located beneath the upper portion of the sternocleidomastoid muscle and extend posteriorly along the course of the spinal accessory nerve. This group of lymphatics receives drainage from the nasopharynx and communicates directly with the upper deep nodes from the internal jugular vein. The posterior triangle nodes in the inferior aspect progress anteriorly to the supraclavicular area to join the internal jugular vein at the base of the neck.

The above groups are easier to understand if they are divided into levels or zones as recommended in the Neck Dissection classification update revision proposed by the American Head and Neck Society and the American Academy of Otolaryngology Head and Neck Surgery.(2002).

Cervical lymph node level and location is as follows:

  • Region/level I

    • Ia - Submental

    • Ib - Submandibular

  • Region/level II

    • Upper jugular lymph nodes, including the jugulodigastric nodes

    • IIa - Nodes in the region anterior to the spinal accessory nerve

    • IIb - Nodes in the region posterior to the spinal accessory nerve

  • Region/level III - Nodes from the carotid bifurcation to the omohyoid muscle

  • Region/level IV - Nodes of the lower jugular area that extend from the omohyoid to the clavicle

  • Region/level V

    • All lymph nodes within the posterior triangle of the neck

    • Va - Spinal accessory nodes

    • Vb - Transverse cervical and supraclavicular nodes.

  • Region/level VI - Nodes in the visceral compartment from the hyoid bone superiorly to the suprasternal notch inferiorly

Nonlymphatic structures

See the list below:

  • Platysma muscle: The rectangular and sheetlike platysma muscle extends obliquely from the upper chest to the lower face, from posteroinferior to anterosuperior. Its undersurface creates an ideal plane in which to elevate the skin flaps in a neck dissection. The platysma muscle is absent in the lower anterior midline of the neck and in the area posterior to the external jugular vein and greater auricular nerve.

  • Sternocleidomastoid muscle: The sternocleidomastoid muscle runs from its anteroinferior attachment to the sternum and medial clavicle, posterosuperiorly to the mastoid tip and surrounding skin. The greater auricular nerve and the external jugular vein cross the upper aspect of this muscle. These structures guide the surgeon to the right plane of dissection and should be left on the surface of the sternocleidomastoid during flap elevation. The fascial envelope of the muscle is a key structure for selective neck dissections.

  • Spinal accessory nerve

    • The spinal accessory nerve crosses over the internal jugular vein in approximately 70% of individuals. The nerve then passes medially to the posterior belly of the digastric and stylohyoid muscles. Anatomic variations include the spinal accessory nerve that runs medially to the internal jugular vein (approximately 30% of individuals) and that runs through the vein (approximately 3% of individuals).

    • The nerve then enters obliquely into the sternocleidomastoid muscle from superior to inferior with the exit at Erb point. The Erb point is near the greater auricular nerve at the posteroinferior edge of the sternocleidomastoid muscle.

  • Digastric muscle: The posterior belly of the digastric is an important landmark. This belly extends from the hyoid bone to the undersurface of the mastoid tip. Important and delicate structures are recognized medial to the muscle. Therefore, it is superficial to the external and internal carotid artery, the hypoglossal nerve, and the internal jugular vein. Lateral to the posterior belly of the digastric, the only structure to be preserved is the marginal mandibular nerve.

  • Marginal mandibular nerve

    • The marginal mandibular nerve is localized deep to the superficial layer of the deep cervical fascia, which covers the submandibular gland and is superficial to the anterior facial vein.

    • The best way to preserve the nerve is to identify it carefully at the above locations. Once the nerve is identified, the tissue lateral and inferior to the nerve can be divided for exposure of the posterior belly of the digastric.

  • Trapezius muscle: The trapezius muscle extends from the posterior occiput to the lateral third of the clavicle. The anterior border of the trapezius is the posterior edge of level V, or the posterior triangle, of the neck.

  • Omohyoid muscle

    • Like the digastric muscle, the omohyoid muscle has 2 bellies. The anterior belly is superficial to the internal jugular vein. The posterior belly is superficial to the brachial plexus, phrenic nerve, and transverse cervical artery and vein.

    • Like the digastric muscle, the omohyoid is a key anatomic landmark in radical neck dissection.

  • Hypoglossal nerve and vagus nerve

    • The vagus nerve in the neck is intimately associated with the carotid sheath and is immediately deep to the internal jugular vein. The vagus nerve may be injured during the dissection and division of the lower portion of the internal jugular vein. Identification of the vagus nerve before division of the internal jugular is mandatory.

    • The hypoglossal nerve in the neck travels under the internal jugular vein, passes over the internal and external carotid arteries, and continues inferior to the posterior belly of the digastric muscle to enter the tongue musculature. Identifying this nerve is important to avoid injury.

  • Brachial plexus and phrenic nerve

    • The phrenic nerve lies above the anterior scalene muscle and deep to the transverse cervical artery. The brachial plexus exits lower in the neck and then passes between the anterior and middle scalene muscles.

    • Identify the anterior and middle scalene muscles before clamping the lymphatic structures. Avoid dissection in the supraclavicular area before phrenic and brachial plexus visualization.

  • Thoracic duct: The thoracic duct, located in the lower left neck, arises posterior to the internal jugular vein and anterior to the phrenic and transverse cervical artery. The anatomy is variable, and the duct has multiple interdigitated channels.

For more information about the relevant anatomy, see Neck Anatomy.and Practical Guide to Neck Dissection.[11]

Contraindications

Since the development of newer surgical procedures minimizing surgical morbidity, the contraindications to a neck dissection have been controversial. However, patients who have too great a surgical risk because of cardiopulmonary disease and whose condition cannot be optimized preoperatively should not be considered for this operation.

Patients in whom preoperative imaging suggests deep infiltration of the tumor in the prevertebral space, scalene muscles, levator scapula muscle, phrenic nerve, and brachial plexus should not be considered suitable candidates. Despite a poor prognosis due to the advanced disease, the resulting morbidity, if not possible mortality, poses no advantage to the patient.

The treatment of patients undergoing carotid vessel management remains controversial. From a radiologic standpoint, carotid artery encasement is defined as disease having surrounded the common carotid or internal carotid artery over more than 270° of encirclement. Many have advocated the preoperative evaluation of these patients with a balloon occlusion test.

Patients who can tolerate the occlusion of the ipsilateral carotid artery without any evidence of neurologic dysfunction may be candidates in whom the carotid segment may be safely resected. The help of a vascular surgeon or a neurosurgeon in these cases may be advisable for reconstruction of the resected segment.

Because patients with significant carotid artery involvement often have preexisting atherosclerotic vascular disease, resection of the carotid artery results in significant morbidity, if not mortality, for most of these individuals.

Contraindications for radical neck dissection also include the following:

  • Primary tumor that cannot be controlled

  • N0 neck

  • Distant metastatic disease

  • Fixed neck mass in the deep cervical fascia and/or skull base involvement

  • Circumferential or near circumferential involvement and invasion of the carotid vessels if the patient cannot tolerate a balloon occlusion test

Extensive metastatic involvement of the platysma and cervical skin is not uncommon and is not a contraindication for a radical neck dissection. However, it requires a wide resection of the area affected with local and regional flap reconstruction of the sacrificed tissue.

 

Workup

Laboratory Studies

Complete blood count

CBC count and differential: The CBC count is important because it gives the clinician a baseline regarding the patient's preoperative hematologic status. Patients with advanced cancers of the head and neck may present with preexisting anemia, which may require further characterization.

Prothrombin time

Prothrombin time (PT), activated partial thromboplastin time (aPTT), and international normalized ratio (INR) measurements: These studies are especially important in patients with preexisting bleeding diathesis, with hepatitis, or who are taking anticoagulants. Prolonged study results may need to be reversed preoperatively.

Electrolyte tests

Preoperative evaluation is important in patients with head and neck cancers. Many present with other medical problems or take medications that affect their electrolyte status.

A subgroup of squamous cell cancers may result in paraneoplastic syndromes; the most common is the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). Management may necessitate consultation with an internist or an endocrinologist.

Other useful tests include the following:

  • Liver enzyme profile

  • Glucose test: This study is useful preoperatively in patients with a history of diabetes.

  • BUN and creatinine testing

  • Blood type and screen: Because of refinements in the surgical techniques, blood loss has been significantly reduced in these procedures. In situations in which blood loss is expected to be significant, either typing and screening or typing and cross-matching are necessary.

  • Urinalysis

Imaging Studies

An esophagogram may be helpful in evaluating an occult esophageal primary tumor.

CT and MRI

CT scan and MRI may be used if they would help to define node status and further treatment planning. They may be crucial in delineating the extent of bony structures, deep cervical musculature, and carotid artery circumferential involvement.

CT scanning with contrast can depict excellent anatomic details and MRI is excellent in soft tissue resolution.

In general, CT is the radiologic technique most commonly used to evaluate the staging of the primary lesion, therefore, the neck should be included in the examination.

Criteria for assessing nodal metastases with CT include increased size, a rounder shape, presence of central necrosis, and nodal grouping. The most accurate CT criterion for the presence of metastatic adenopathy is central necrosis. The node periphery is usually thick and enhances with contrast. CT scanning also reveals extracapsular spread by enhancement of the nodal capsule.

Some radiologists feel that CT demonstrates paratracheal node involvement better than MRI.

MRI has surpassed CT scanning as the preferred study in the evaluation of cancer at primary sites, eg., base of the tongue.

MRI reveals tumor necrosis and extracapsular spread with less precision than CT scan, but MRI is better for assessing enlarged lymph nodes that are not necessarily metastatic.

MRI may also be used in patients who are allergic to iodinated contrast.

According to some radiologists, MRI also appears to reveal retropharyngeal node involvement better than CT.

Ultrasonography/Ultrasound

Some institutions use ultrasonography and ultrasound-guided aspiration cytology to determine cervical neck metastasis. Ultrasound-guided aspiration cytology has a specificity of nearly 100%.

PET

PET and PET/CT have recently emerged as an adjunct in the diagnosis of lymph node metastasis.

In recent studies, PET has shown positive findings for lymph node metastasis when CT scan and MRI findings were negative. An FDG-PET scan provides physiologic and biochemical data. Glucose metabolism in neoplastic cells produces increased uptake on FDG-PET scanning, which correlates strongly with viable tumor cells. Therefore, FDG-PET may be helpful in the assessment of neck metastasis and even distant metastasis.

Additionally, PET scanning has shown the ability to differentiate active tumors from chronic fibrotic changes. Therefore, PET may become more useful than CT and MRI in the detection of recurrent head and neck cancer. Furthermore, the dual use of the PET and CT scanners produces fused PET and CT images, which can further enhance the results of the PET scan. The definitive role of PET and PET/CT scans is evolving and showing great potential in the assessment of metastatic neck disease, the early diagnosis of recurrent head and neck cancer, and the status of the neck after chemoradiotherapy.

The most recent diagnostic guidelines for the use of PET/CT in head and neck oncology are (1) detection of occult primary tumors, particularly in patients in which the conventional imaging tests are negative; (2) initial staging for detection of neck metastasis in the negative neck after evaluation with CT or MRI; (3) detection of distant metastasis in patients with advanced metastatic neck disease; and (4) detection of residual or recurrent disease.

If tumor involvement of the carotid artery is suspected, a complete preoperative evaluation of the carotid system is indicated. This includes a balloon occlusion test and a 4-vessel cerebral angiography to evaluate the status of the contralateral carotid, intracerebral circulation, and carotid back pressure.

Perform chest and/or chest CT radiography to exclude metastatic disease in high-risk patients.

 

Other Tests

A complete physical examination is mandatory and includes evaluation of neurologic, cardiovascular, and respiratory status.

  • Palpate the patient's neck to define size, location, mobility, and degree of softness or hardness of any mass.

  • Evaluate the patient's weight and nutritional status.

  • Perform an ECG as indicated.

Evaluation by medical service personnel and further medical consultations may be indicated.

Diagnostic Procedures

The historic and long-standing mirror laryngoscopy (indirect laryngoscopy) has been progressively supplanted by the use of the flexible nasopharyngolaryngoscopy, or rigid scopes to supplement the examination of the upper aero-digestive tract

When the primary tumor is known, perform a panendoscopy to exclude a second primary tumor. Performing biopsy of the primary lesion is necessary. When the primary tumor is not known, perform a panendoscopy to look for the primary tumor and to perform random biopsies of the pyriform sinus, base of tongue, and nasopharynx to exclude occult tumors. An ipsilateral tonsillectomy is also advocated; however, this has been the subject of controversy for many surgeons.

Transnasal esophagoscopy for screening has emerged in the last decade as safe and well tolerated by patients as an office procedure with topical anesthesia alone. The transnasal esophagoscopy instrumentation set has a suction port, a biopsy port and an insufflator. Therefore, transnasal esophagoscopy can be used for assessment of the esophagus and also for biopsy of suspicious lesions in the supraglottic area. Its role is expanding for use in outpatient "panendoscopy" and biopsy.

When the patient has a neck mass, a fine-needle aspiration biopsy for cytology evaluation may be useful in helping the clinician determine management.

An open biopsy of a neck node is indicated only when the previous measures of physical examination, needle aspiration biopsy, random biopsies, and endoscopy are inconclusive. To circumvent this situation, patients are asked to sign a consent form for a possible neck dissection when a frozen section diagnosis confirms the presence of malignancy in the open node biopsy specimen.

Sentinel lymph node biopsy[12, 13, 14, 15] : A sentinel node is the first node of a particular group of nodes to receive the regional lymphatic flow from the primary site. The concept and the procedure for the sentinel lymph node biopsy in the evaluation of metastatic neck nodes in patients with head and neck squamous cell carcinoma is similar to the one used in the evaluation of nodal disease in skin melanoma. If the sentinel lymph node biopsy is negative, no further lymphadenectomy surgery is necessary. However, the sentinel lymph node biopsy applied to the mucosal cancer of the upper aerodigestive tract is still in the process of evaluation in research trials. Results in this regard are encouraging and useful- in particularly - in patients with clinical N0 neck and early carcinomas of oral cavity T1-T2. Nevertheless, its application in the assessment of neck metastasis is still not established and/or standardized in the clinical setting.[16]

Biotumor markers and molecular methods[17, 18] : New research techniques have been developed to detect micrometastasis of squamous cell carcinoma by using highly specific biotumor markers and molecular methods. The research is this regard is very active, with goals to impact diagnosis, prognosis, and therapy. However, the practical application, prognosis, and management significance is unknown until further studies are completed in prospective clinical trials.[19, 20, 21]  

 

Histologic Findings

Biopsies of the primary site reveal the etiology of the initial mass and the characteristics of the tumor involved, such as squamous cell carcinoma of the upper aerodigestive tract, nasopharyngeal carcinoma, thyroid carcinomas, and skin cancer of the head and neck.

Fine-needle aspiration cytology of the neck confirms the pathology findings of the primary tumor. It also helps to determine the etiology of the cervical adenopathy when the patient has a neck metastasis from an occult primary tumor.

 

Treatment

Surgical Therapy

Surgical alternatives to radical neck dissection (classic), when indicated and oncological feasible, include the following:

  • Modified radical neck dissection type I

  • Modified radical neck dissection type II

  • Modified radical neck dissection type III

  • Selective Neck Dissection

(The reader is refered to the Indications section to understand the rationale for the several neck dissection options.)

Other associated surgeries include the following:

  • Laryngectomy

  • Composite resection

  • Glossectomy

  • Tracheotomy (The patient may need a tracheotomy for control of the airway, particularly when radical neck dissection is associated with a composite resection. Also, consider a tracheotomy in any patient undergoing surgery that may lead to airway compromise.)

  • Dermal graft (Although optional, a dermal graft has been used over the bifurcation of the carotid artery when a pharyngotomy surgery is combined with a radical neck dissection or radiation therapy. The levator scapulae muscle can be transposed forward over the carotid system for the same reason.)

Preoperative Details

The following items should be noted on the patient's record before performing surgery:

  • Physical examination findings, including those of a head and neck examination

  • Medical history (eg, allergies to medications; hypertension, diabetes, cardiopulmonary disease, and other chronic illnesses; previous surgeries, radiation therapy)

  • Medical clearance and recommendations

  • All test results, including biopsy and fine-needle aspiration results

  • Informed consent with risks and complications having been fully discussed with the patient

  • Summarized problem and treatment plan, including alternative plans

Other preoperative details include the following:

  • Evaluate the airway and dentition of the patient.

  • Evaluate the ability of the patient to open his or her mouth adequately for intubation.

  • If the patient has a tracheotomy, evaluate the airway and status of the tracheotomy.

  • The patient should remain on nothing by mouth (NPO) status after midnight.

  • Instruct the patient to take the usual medications up to midnight the night before the surgical procedure.

  • Note premedication order on record.

  • Void on call to the operating room.

  • Preoperative antibiotics are required if the procedure involves going through the neck into the upper aerodigestive tract.

Intraoperative Details

If the airway is obstructed (see Preoperative details), the tracheotomy is preferably done with the patient under local anesthesia. An obstructing neoplasm of the upper aerodigestive tract can bleed easily at intubation, producing a sudden, total airway obstruction in an already compromised airway. Prevention and planning are mandatory.

In a difficult but not obstructed airway, the anesthetist may perform an awake intubation with the assistance of a flexible nasopharyngolaryngoscopy to accomplish a nasotracheal intubation. As an alternative, DL + VL (Direct Laryngoscopy and Video Laryngoscopy) intubation devices can also be used to achieve proper endotracheal intubation in these patients. The intubation can be obtained by direct visualization, or by video imaging in the screen or a combination of both. There are several DL/VL devices available on the market today.

Airway compromise or marginal compromise in patients with head and neck cancer is not uncommon. Therefore, good communication and understanding between the surgeon and the anesthetist is essential.

A urologic catheter is not needed during radical neck dissection. If the surgery is performed with other procedures that are more complex and prolonged, insert a catheter for better control of urine output.

Place the patient in the supine position with a shoulder roll extending the neck. Elevate the upper half of the operating table to a 30° angle. The patient's neck and upper chest are prepared and draped in a sterile fashion for the proposed surgery. Use staples or sutures to delineate the field.

Several incisions are designed and used by various surgeons. If a radical neck dissection is to be performed alone, the hockey stick incision is generally preferred. The neck incision changes depending on the location of the primary tumor and whether one or both sides of the neck are operated on. In general, the incisions are designed to avoid trifurcation over the carotid artery and to avoid narrow flaps.

Mark the skin incision with methylene blue or a surgical marking pen. Some authors infiltrate the skin incision with 10 mL of lidocaine with 1:100,000 epinephrine to minimize bleeding. The author's institution does not infiltrate the skin incision.

Make scratch marks to assist in the alignment of the flaps at the end of the operation.

Make the skin incision through the platysma and elevate the flap in the subplatysmal plane as seen in the image below. Traction with the surgeon's fingers and countertraction by the assistant with 2 double skin hooks are helpful in this maneuver. After raising the superior lateral aspect of the flap, leave the greater auricular nerve and external jugular vein on the sternocleidomastoid muscle. Elevate the posterior flap toward the trapezius muscle.

The skin incision is made through the platysma, an The skin incision is made through the platysma, and the flap is elevated in the subplatysmal plane. In the superior lateral aspect of the flap, leaving the greater auricular nerve and the external jugular vein on the sternocleidomastoid muscle is important. The posterior flap is elevated toward the trapezius muscle.

Identify and preserve the marginal mandibular nerve at the superior aspect of the flap. This nerve passes deep to the platysma muscle, often dropping inferiorly to 2 cm below the body of the mandible. This nerve passes within the fascia of the submandibular gland. A simple way to protect this nerve is to divide the anterior facial vein at the anterior border of the sternocleidomastoid muscle and to dissect the superior flap deep to this vein.

Some surgeons proceed from below to above, and others do the opposite. The author's institution usually proceeds first with the zone I dissection and then from inferior to superior.

Remove submental fatty tissue with Bovie electrocautery and displace it inferiorly. Retract the mylohyoid muscle anteriorly, exposing the submandibular ganglion, lingual nerve, and submandibular duct. Ligate the facial artery above the digastric muscle. Cut and ligate the submandibular duct. Remove the submandibular nodes and the submandibular gland and displace them inferiorly. The dissection continues posteriorly, exposing the posterior belly of the digastric and stylohyoid muscles and transecting the tail of the parotid gland.

Expose the sternocleidomastoid muscle and incise it above the clavicle with Bovie electrocautery as seen in the image below.

The sternocleidomastoid muscle is exposed and inci The sternocleidomastoid muscle is exposed and incised above the clavicle with Bovie electrocautery.

Identify the anterior and posterior belly of the omohyoid with transection of the omohyoid posteriorly. Note that the omohyoid crosses the internal jugular vein laterally as seen in the image below.

The anterior and posterior belly of the omohyoid i The anterior and posterior belly of the omohyoid is identified. Note that the omohyoid crosses the internal jugular vein laterally.

Identify the internal jugular vein and vagus nerve in the lower aspect of the neck before ligation of the internal jugular vein. Pass a 2-0 silk suture around the vein and tie it as depicted in the image below.

The internal jugular vein is identified in the low The internal jugular vein is identified in the lower aspect of the neck, and a 2-0 silk suture is then passed around the vein and tied.

Using 2-0 silk, place a distal suture ligature while the vein is still intact. Place 2 similar sutures cephalic and transect the vein as seen in the image below.

2-0 silk sutures and suture ligatures are placed a 2-0 silk sutures and suture ligatures are placed as shown.

Further identify the carotid artery and the vagus nerve. Open the supraclavicular fatty tissue using blunt dissection, either with a finger or hemostat, with identification of the phrenic nerve and brachial plexus as seen in the image below.

The supraclavicular fatty tissue is opened using b The supraclavicular fatty tissue is opened using blunt dissection with identification of the phrenic nerve. The phrenic nerve appears as a white cord down the midline of the anterior scalenus muscle. The internal jugular vein has been ligated and transected. The carotid artery is seen on the top of the image. The transverse cervical artery is seen at the bottom of the image.

Once the brachial plexus is visualized, blunt dissection with the surgeon's finger permits clamping of the fibrofatty tissue with a large clamp. The spinal accessory nerve is sacrificed in the radical neck dissection; therefore, no identification of the nerve is required.

Pull up Dissect from inferior to superior as depicted in the image below.

The submental fatty tissue, the submandibular node The submental fatty tissue, the submandibular nodes, and the submandibular gland have been removed and displaced inferiorly together with the specimen.

Continue the dissection along the anterior border of the trapezius. Preserve the phrenic nerve and brachial plexus. Follow the cervical nerve branches and section them high on the specimen. Separate the surgical specimen from the carotid and vagus, proceeding superiorly, with identification of the hypoglossal nerve. Preserve the superior thyroid artery and superior laryngeal nerve and carefully ligate the ranine veins. Cut the sternocleidomastoid muscle superiorly in the same manner as described above. The division is made high, and the surgeon is just lateral to the posterior belly of the digastric muscle. Identify the internal jugular vein superiorly, medial to the posterior belly of the digastric muscle. Dissect and ligate in the fashion described above and also depicted in images below.

Within the last 3 years, the authors have introduced the use of the harmonic scalpel[22] in the execution of the radical neck dissection. Its progressive use has displaced, in part, most other conventional intraoperative techniques used for providing hemostasis (eg, clamping, tying, electrocauterization). The authors have also found that using this tool shortens intraoperative time and diminishes bleeding. See the images below.

The internal jugular vein is identified superiorly The internal jugular vein is identified superiorly, medial to the posterior belly of the digastric muscle. The ligation of the internal jugular vein at this point is performed with a 2-0 silk suture and a distal suture ligature.
Final aspect of the surgical wound after removal o Final aspect of the surgical wound after removal of the operative specimen.

Endoscopic and robotic neck dissections

Minimally invasive surgery with the assistance of endoscopic and robotic instrumentation[23, 24, 25] has been tried in head and neck cancer management, including neck dissection for cervical metastatic disease. The viability of neck dissection has been demonstrated using this armamentarium; however, its oncological application in the management of neck metastasis versus the classic open approach remains to be seen. Further assessment and follow-up are needed prior to its application in routine clinical practice.[26]

Current Procedural Terminology code (CPT coding)

See the list below:

  • 38720, Radical Neck Dissection (Cervical Lymphadenectomy, complete)

  • 38720 with modifier 50, Radical Neck Dissection for bilateral procedure

Surgical pearls and quick tips

See the list below:

  • Radical neck dissection/definition

    • Surgical removal of metastasis contained in the neck involves the removal of structures between the superficial and deep fascial layers and the ipsilateral lymphatic structures from the mandible above to the clavicle below and from the infrahyoid muscles to the anterior border to the trapezius.

    • The classical radical neck dissection includes resection of the sternocleidomastoid muscle, the internal jugular vein and the spinal accessory nerve.

    • The classical radical neck dissection does not include the central compartment of the neck, postauricular, suboccipital, perifacial, buccinator, retropharyngeal and periparotid nodes (in this area the nodes located in the tail of the parotid are included in the classical RND).
  • Incision design

    • Try not to use trifurcation, if possible.

    • If trifurcation is used, it should not lie over the carotid artery.

    • Incise the skin and platysma muscle, except if invaded by tumor.

  • Medial landmark: This landmark is the superior belly of the omohyoid muscle/hyoid bone.

  • Posterior landmark: This landmark is the anterior border of the trapezius muscle.

  • Internal landmark: This landmark is the scalenus fascia muscle. (There is no need to dissect behind the carotid artery.)

  • Anatomical structures to be sacrificed

    • Internal jugular vein

    • Spinal accessory nerve

    • Sternocleidomastoid muscle

    • Cutaneous branches of the cervical plexus

    • Submandibular gland and Wharton duct

    • Tail of the parotid gland

    • Greater auricular nerve

    • External jugular vein

    • Posterior facial vein

    • Ligation of the facial artery

    • Omohyoid muscle

  • Anatomical structures to be preserved (if possible)

    • Marginal mandibular nerve

    • Digastric muscle with both bellies and tendon

    • Lingual nerve and submandibular ganglion

    • Superior laryngeal nerve

    • Superior thyroid artery

    • Hypoglossal nerve

    • Vagus nerve

    • Carotid vessels

    • Phrenic nerve

    • Brachial plexus

    • Thoracic duct

    • Note: Oncologic involvement of the platysma and cervical skin requires a wide resection of the area affected with local and regional flap reconstruction of the sacrificed tissue. If the tumor is extensive, the external carotid artery, digastric muscle, and hypoglossal and vagus nerves need to be included in the resection (extended radical neck dissection). Occasionally, the resection of the common carotid and the internal carotid artery may be considered.

Key anatomical structures

See the list below:

  • Marginal mandibular nerve: Identify and preserve the nerve by direct visualization, electrical stimulation or by identification of the anterior facial vein and elevate below its plane.

  • Mylohyoid muscle

    • Retract the mylohyoid muscle anteriorly to expose and identify the deep lobe of the submandibular gland, the hypoglossal nerve and Wharton duct.

    • The hypoglossal nerve is identified and preserved. The lingual nerve and the submandibular ganglion are identified and preserved.

    • The facial artery is identified and ligated above the digastric muscle.

    • Remove the submandibular nodes and the submandibular gland and displace the specimen inferiorly.

  • Posterior belly of the digastric muscle

    • Identify and follow the entire posterior belly of the digastric muscle.

    • Identify medial to the muscle, the external and internal carotid arteries, the hypoglossal nerve and the internal jugular vein.

    • Identify the spinal accessory nerve lateral to the internal jugular vein.

    • The internal jugular vein is transected and ligated superiorly

  • Superior border of the clavicle

    • This is the limit of the inferior dissection.

    • The sternocleidomastoid muscle is incised.

    • Excise the external jugular vein and identify the omohyoid muscle.

  • Omohyoid muscle

    • Identify medial to the anterior belly of the omohyoid the internal jugular vein, common carotid and vagus nerve.

    • Ligate the internal jugular vein with clear visualization of the vagus nerve.

    • Identify medial to the posterior belly the brachial plexus, the phrenic nerve and the transverse cervical artery and vein.

  • Internal jugular vein: Identify and ligate the Internal jugular vein, superiorly and inferiorly, as described in the intraoperative details.

  • Vagus nerve

    • Identify and preserve the vagus nerve (mandatory) prior to ligation of the internal jugular vein in the supraclavicular area.

    • The vagus nerve is located deep to the internal jugular vein.

  • Phrenic nerve: Identify and preserve the phrenic nerve above the anterior scalene muscle and medial to the transverse cervical artery.

  • Brachial plexus

    • Identify and preserve the brachial plexus in the lower neck between the anterior and middle scalene muscles.

    • Divided the cutaneous branches of the cervical plexus.

  • Spinal accessory nerve

    • Identify and transect the spinal accessory nerve superiorly, just lateral to the internal jugular vein, although variation occurs. (see anatomy for details)

    • Identify and transect the spinal accessory nerve inferiorly in its course oblique and caudal to the level of entry into the ventral border of the trapezius muscle.

  • Carotid bulb

    • Follow the common carotid inferiorly superiorly.

    • Identify the carotid bulb.

    • Identify the hypoglossal nerve above the carotid bulb.

    • Follow the hypoglossal nerve deep to the digastric tendon and deep to the submandibular space.

    • Identify the internal and external carotid arteries.

Irrigate with isotonic sodium chloride solution. Maintain hemostasis. Insert drains (0.125-in Hemovac or Jackson-Pratt); usually, use 2 for each side of the neck. Close the wounds in layers with 3-0 Vicryl through the platysmal flaps and staples or 4-0 nylon for the skin.

No compressive dressing is used for bilateral neck dissections. Some surgeons use a compression dressing for unilateral neck dissection.

When preparing the pathology specimen, plastic plates with life-size drawings of the different areas of the neck are recommended for orientation. The unfixed specimen is placed as it appears in the patient and brought to the pathology department from the operating room. The type of dissection performed is written clearly on the requisition slip.

Special considerations

Advanced deeply attached neck metastasis, recurrence after radiation or chemoradiation, and metastatic neck abscess pose several technical challenges for the head and neck surgeon in the salvage operation. Frequently, the neck has acquired a hard boardlike consistency or a frozen-neck appearance, which makes the dissection and identification of anatomical structures difficult. In these cases, the authors proceed with radical neck dissection in a nonstandardized fashion—from the known to the unknown, from superficial to deep, and from the easy areas to the more difficult areas. Along the way, the authors identify major vascular and nervous structures and take small dissection steps.

Most of the time, the Bovie electrocautery unit is used with the assistance of the gentle spreading action of an intermediate hemostat. With this technique, the metastatic mass is dissected en bloc in a circular fashion (superiorly, inferiorly, laterally, medially [in no particular order]). The authors Identify key anatomical structures such as the anterior and posterior belly of the digastric muscle; the omohyoid muscle; the facial artery; the vagus, hypoglossal, and phrenic nerves; the internal jugular vein; and the carotid artery until the entire specimen is dissected, except in its deepest plane.

In cases of advanced metastasis, recurrence after chemoradiation, or metastatic neck abscess, the internal jugular vein is not usually problematic because, in most cases, this vein is already nonfunctional, either because of invasion or compression-blockage by the mass, which occurs superiorly, inferiorly, or both. The vein is usually smaller, and ligation or transfixation-ligation is feasible. However, careful dissection is required over the carotid artery, particularly if infiltration by the tumor is present. Therefore, the deep plane of the mass over the carotid artery is addressed last, as further assessment is needed to determine involvement or invasion prior to consideration of different surgical options.

Modifications to the radical neck dissection

If the spinal accessory nerve is preserved, identify the nerve in the posterior triangle and dissect it from the anterior border of the trapezius to the sternocleidomastoid muscle until it is free. If the internal jugular vein is preserved, identify it posteriorly after the cervical nerve branches are divided. Then, peel the vein from the surrounding tissue until it is free. Perform this in the same fashion in selective neck dissection. If the sternocleidomastoid is to be preserved, the procedure is performed by peeling the fascia from the muscle. This is done in the same fashion in selective neck dissection.

Postoperative Details

Immediate postoperative guidelines

See the list below:

  • Maintain nothing by mouth status for at least the first 24 hours. If the radical neck dissection has been combined with more extensive surgical procedures, a longer period may be needed.

  • Maintain head elevation at a 30° angle.

  • Monitor vital signs, intake, and output every 4 hours.

  • Maintain constant humidification, suctioning, and cleansing of the tracheotomy tube.

  • Administer pain medications as needed.

  • Ensure that the Hemovacs or drains are functioning properly.

  • Ensure that drains are maintained on continuous suction until they drain less than 20-25 mL in 24 hours.

  • Ensure that the drains do not clot.

  • Administer antibiotics for the first 24 hours if the surgery involved opening the neck and the upper aerodigestive tract.

  • Monitor for fever, bleeding, or hematoma formation in the postoperative period.

  • Avoid atelectasis. Move the patient out of bed the day after surgery with assistance. Encourage deep breathing and early ambulation with assistance.

  • Monitor for possible fistula if the oral or upper digestive tract was opened, particularly during the third or fourth postoperative day.

Discharge criteria

Once the suction and drains have been removed, the patient can be discharged from the hospital, usually on the fourth or fifth postoperative day, if the following conditions are met:

  • Satisfactory healing of the surgical wound

  • No evidence of bleeding or infection

  • Adequate airway and nutrition

  • Hemodynamic stability

  • Adequate family or home care support

  • Initiation of physical therapy to the shoulder before discharge and continuation at home

If another surgical procedure was performed in addition to radical neck dissection, the discharge day varies.

Follow-up

See the list below:

  • Call the patient at home after discharge to check on progress.

  • Arrange for the patient to return to clinic (RTC) in 7-10 days.

  • Check the pathology report for complete or incomplete resection and free margins.

  • Check the pathology status of the neck.

  • Evaluate for further consultations and adjunctive treatment as needed.

  • Remove sutures or clips at 7-14 days; however, when radiation therapy has been administered, they should remain in place for at least 10 days after the operation.

  • Continue with shoulder physical therapy if necessary.

Follow-up care is mandatory to check for recurrent tumor or development of a second primary tumor. Therefore, the patient should be seen every month for the first year, particularly if no primary lesion was initially found. Continue follow-up care every 2-4 months for up to 5 years. After this interval, the patient may be seen yearly. Advise the patient to call for an immediate appointment if the patient's condition suddenly changes.

For excellent patient education resources, see eMedicineHealth's patient education article Cancer of the Mouth and Throat.

Complications

Radical neck dissection has been a well-established procedure for surgical removal of neck node cancer for almost a century. A radical neck dissection alone has low morbidity and mortality rates; however, the association of composite resection and ablation of a large surface of mucosal area adjacent to the neck markedly increases the rate of complications.

Previous radiation therapy is another factor associated with a high complication rate. Other factors, such as poor general health, chronic malnutrition, alcoholism, diabetes mellitus, advanced age, and systemic illness, also increase the percentage of complications.

Intraoperative complications

See the list below:

  • Hemorrhage

    • Severe blood loss is an uncommon complication for an experienced head and neck surgeon. The average blood loss in the realization of a radical neck dissection is 200 mL or less; it varies slightly according to the surgical technique and among surgeons. With careful attention to anatomy, hemostasis with the electrocautery unit or bipolar forceps and use of clamps and suture ligation have allowed an almost bloodless neck operation. The recent addition of the harmonic scalpel to the armamentarium has allowed a shortening of the operative time and diminished bleeding.

    • Major vessel trauma, laceration, tear, or transection (internal jugular vein, junction of internal jugular vein and subclavian and/or carotid arteries) is presently a rare occurrence. Immediately repair injury to the carotid artery during surgery.

    • Consultation with a vascular surgeon may be useful depending on the intraoperative findings. A small tear or laceration requires primary closure with a 6-0 continuous vascular suture. Other types of injuries may require ligation or reconstruction. Injury to the internal jugular vein at the upper or lower ends may be a serious problem.

    • If the lower end of the jugular vein bleeds excessively, pressure is the first aid, followed by adequate visualization and suctioning until the stump is identified, dissected, and ligated properly. Occasional uncontrollable bleeding requires the assistance of a thoracic surgeon to enter the superior mediastinum.

    • If the upper end of the vein bleeds and the stump has retracted into the temporal bone, packing the jugular foramen with large pieces of Surgicel, plicating with the posterior belly of the digastric muscle, or both are sufficient to solve the problem.

  • Carotid sinus reflux: Hypotension caused by carotid sinus reflux may occur upon dissection around the carotid bifurcation. This may be avoided by careful dissection at the carotid bifurcation without manipulation, injection of 2 mL of local anesthetic into the adventitia at the carotid bifurcation between the internal and external carotid arteries, or both.

  • Pneumothorax

    • Pneumothorax involves a sudden compromise of the respiratory and circulatory system and causes difficult breathing, bronchospasm, and decrease in oxygen saturation. The pressure of the anesthetic bag does not cause normal expansion of the thorax.

    • This complication is rare today. To minimize the chance of pneumothorax, carefully dissect in the paratracheal area and base of the neck with good hemostasis, adequate visualization, and careful dissection of the tissues close to the apex of lung.

    • If the pneumothorax is small, close the wound with an airtight seal. Follow-up care with conservative management controls the situation without sequelae. Conversely, a large pleural leak with a tension pneumothorax requires immediate aspiration with a No-14 or No-16 needle in the upper anterior thorax, placement of a chest tube with an underwater drain, or both.

  • Air embolus

    • This complication is also rare today. Air embolism can occur when a large vein is inadvertently opened. A large volume of air enters rapidly into the open vein by negative pressure and passes directly into the right atrium, causing a sudden alteration of the central circulation, leading to tamponade of the heart and even death. Clinically, cyanosis, hypotension, and a loud churning noise over the precordial area appear suddenly, and the peripheral pulse disappears.

    • The treatment of air embolism requires packing or clamping the offending vein immediately and turning the patient onto the left side with the head down. Cardiac arrest may occur, requiring aspiration of the air from the heart, massage, and standard resuscitation procedures. Prevention is best, with careful identification and clamping of the major veins of the neck. Adequate ligations and transfixion sutures are mandatory.

  • Embolism: Embolism may occur and lead to stroke. Most patients with cancer are of the age at which arterial cerebrovascular disease is common. Careful handling of the carotid arterial system in the neck with gentle retraction, ligation, and manipulation prevents the dislodgment of arteriosclerotic plaques from the internal carotid system.

  • Nerve damage

    • The neck area has multiple sensory nerves that are sacrificed during radical neck dissection. Therefore, a loss of sensation occurs in multiple areas, including the neck, posterior occiput, external ear, mandibular region, lateral shoulder, deltoid area, and upper pectoral area. On occasion, the formation of a neuroma at the end of a cut nerve may cause paresthesias and pain.

    • The ramus mandibularis is preserved in most neck dissections unless it is involved by metastatic disease. The transection of the marginal mandibular branch of the facial nerve produces lower lip weakness. If the tail of the parotid is resected, follow the nerve into the parotid tissue before the removal of this tissue.

    • The sacrifice of the cervical sympathetic chain produces Horner syndrome, which involves ptosis, anhidrosis, and miosis.

    • The sacrifice of the spinal accessory nerve, mandatory in the classic radical neck dissection, produces shoulder drop with local pain in the affected area and limitation in the range of motion of the arm and shoulder. Most patients tolerate this disability and improve markedly with physical therapy. In type I modified neck dissection, the spinal accessory nerve is preserved, therefore sparing the consequences of the nerve's sacrifice.

    • Unilateral resection of the hypoglossal nerve is usually well tolerated without serious sequelae; however, bilateral hypoglossal nerve resection causes a severe disability with serious difficulties in feeding, swallowing, and speaking. On occasion, a feeding gastrostomy tube is recommended for adequate nutrition.

    • Resection of the lower or middle neck of the vagus nerve, which carries motor and sensory branches to the larynx and pharynx, causes vocal cord paralysis.

    • Avoid injuring the brachial plexus by properly identifying the anatomic planes. Reapproximate the sectioned brachial plexus with an 8-0 or 9-0 nylon monofilament or silk.

  • Poor wound healing after radiation or chemoradiation therapy: Patients who have received radiation or chemoradiation therapy before radical neck dissection tend to have increased postoperative complications (eg, wound infection, fistula, flap necrosis, osteoradionecrosis, carotid artery rupture).

  • Chylous fistula

    • Chylous fistula is a complication occasionally produced during dissection of the thoracic duct region. Most chylous fistulas occur on the left side. If it occurs, ligate the thoracic duct.

    • Reinspect the area before completing the surgery. Ask the anesthesiologist to apply positive pressure to reevaluate if further leaking occurs. A small leak can be identified with the assistance of the microscope. Ligation is mandatory. A suture ligation with a figure 8 using 4-0 silk is usually satisfactory. Hemoclips also have been used when the leakage is clearly visualized.

Postoperative complications

See the list below:

  • Hematoma

    • Meticulous hemostasis during the surgical procedure is mandatory. Use suction drains to avoid accumulation of blood under the skin flap and to prevent the formation of a hematoma. Some surgeons also use a floppy, moderately compressive dressing in addition to the suctioning system mentioned above. The disadvantage is that the compressive dressing leaves the flaps unavailable for inspection, which is the best way to watch for the formation of a hematoma.

    • A hematoma is usually evident in the first few hours after the operation. Sudden bleeding in the postoperative period indicates that an untied vessel has opened or that a ligature has slipped from the vessel. Blood under the flap accumulates rapidly.

    • The treatment of a hematoma comprises taking the patient to the operating room, opening and elevating the neck flaps, and evacuating the hematoma. Irrigate the surgical field with isotonic sodium chloride solution, and, if any source of bleeding is found, ligate, suture, or electrocauterize to achieve hemostasis.

    • If the hematoma is recognized and treated early, no adverse consequences occur. However, if the hematoma is found late, airway compromise, infection, or flap necrosis may occur.

  • Wound infection

    • Wound infection is unlikely when radical neck dissection is performed alone; however, when radical neck dissection is performed in combination with the opening of the upper aerodigestive tract as part of a composite resection or a laryngectomy, the potential for wound infection increases markedly. A salivary contamination from the oral cavity is possible, with the consequences of bacterial invasion and wound infection.

    • All irradiated tissues are more susceptible to infection because of ischemia and hypoxemia. Other factors that increase the possibilities of wound infection include malnutrition, chemotherapy, anemia, diabetes mellitus, and advanced tumor mass.

    • If a wound infection develops, open the flap, culture and evacuate pus, and irrigate the wound. Administer antibiotics that cover anaerobic, gram-positive, and gram-negative organisms. Carefully debride necrotic tissue. Local care with frequent dressing changes, control of salivary fistula, and irrigation of the wound is important. Once the infection is under control and the necrotic tissue is removed, healthy granulation tissue appears.

  • Skin flap loss

    • Necrosis of the skin flap can be caused by several occurrences (eg, poor vascularity, errors in design, elevation, poor handling, improper postoperative care). Preexisting scars, hematoma, infection, and poor nutrition may contribute to the skin flap loss. If skin flap necrosis occurs and the carotid is not exposed, a conservative approach is mandatory. Carefully and progressively trim necrotic tissue and dress the wound regularly.

    • However, if the carotid artery is exposed because of the loss of skin, coverage is needed to avoid carotid artery rupture. The flaps used in the management of carotid exposure include the deltopectoral, pectoralis major, and trapezius.

    • When skin necrosis, infection, and accumulation of pus adjacent to the carotid wall are present, the carotid artery may rupture. Management is on a patient-by-patient basis. Initially, control of infection, wound cleansing, and local care are priorities. The decision between flap coverage and secondary healing is then made.

  • Salivary fistula

    • Salivary fistula occurs more frequently when a patient has received previous radiation therapy and the oral cavity, pharynx, or cervical esophagus has been opened in association with the neck dissection. Good surgical technique with double-layer closures and watertight closures without tension minimize this complication. Use Vicryl or Dexon sutures in high-risk patients. Low-suction drainage is recommended. Do not place Hemovac drains over the carotid arteries. Usually, the fistula appears within 4-5 days of surgery; however, fistulas may be seen after an interval of up to 2-3 weeks in patients with a history of preoperative irradiation.

    • The fistula may range from a small leak that is well managed by conservative measures (eg, frequent change of dressing, local care) to a large leak that involves infection of the whole neck with flap necrosis. These patients require enteral or parenteral feeding, controlled exteriorization of the fistula, and local care before closure of local skin or myocutaneous flaps.

  • Chylous fistula: Chylous fistula is evident in the postoperative period in approximately 1-2% of patients who undergo neck dissection procedures. Chyle can be identified by the appearance of a milky clouded fluid in the Hemovac drains. Chyle accumulation under the flap can cause redness and swelling of the flap with induration of the surrounding tissues. The leak, if minimal, is usually controlled by aspiration, pressure dressings, and a low-fat diet. Ligation of the offending thoracic duct is required when the leak is extensive with more than 500 mL of drainage and when conservative management has not led to demonstrated improvement.

  • Facial edema

    • Unilateral radical neck dissection may result in swelling of the lower face and neck on the ipsilateral side. The edema reaches a maximum at 1 week and progressively decreases in a few weeks.

    • Bilateral radical neck dissection performed simultaneously with ligation or resection of both internal jugular veins results in facial edema, cerebral edema, or both. Mechanical obstruction of venous drainage and the increase of intracranial pressure can cause neurologic deficit and coma.

    • Facial edema commonly appears in patients with previous irradiation and can lead to chemosis. Edema of the lids may be sufficient to prevent opening of the eyes. Airway management with a tracheotomy is required. If bilateral radical neck dissection is needed, preserving one external jugular vein can lessen this complication. Staging the neck dissections 4-6 weeks apart also helps.

  • Electrolyte disturbances: The most common electrolyte disturbance in the postoperative period is hyponatremia. It is usually dilutional; however, it may be related to the secretion of antidiuretic hormone. Clinically, it can be manifested by mental changes, including depression and hallucinations. Occasionally, hypernatremia, hypokalemia, hypercalcemia, and hypophosphatemia are also associated with radical neck operations.

  • Carotid artery rupture

    • The incidence of this complication ranges from 3-7%. The precipitating factors of carotid artery rupture include the following:

      • Radiation therapy

      • Infection and salivary fistula

      • Suction catheters that cause erosion of the vessel wall

      • Exposure by dehiscence of the suture line or necrosis of the dermis

    • Rupture occurs in patients who underwent neck surgery with exposure of the carotid artery and one or more of the precipitating factors named above. Most patients have prodromal bleeding (ie, sentinel bleed) within 48 hours of the carotid rupture. Therefore, the initial bleeding should indicate that a serious complication could be avoided with the elective ligation of the offending artery. Immediate treatment for carotid rupture includes the following:

      • Apply direct and firm pressure to the affected area. The operating room should be prepared for neck surgery. Suctioning, good illumination, and adequate instrumentation are imperative.

      • Cannulize a peripheral vein in each of the patient's arms with a large-bore catheter for immediate administration of fluids (Ringer lactate or isotonic sodium chloride solution). Controlling blood pressure and blood volume before the ligation is important.

      • The airway should be adequate and stable. If the patient does not undergo a tracheotomy, orotracheal intubation may be necessary.

      • Type blood and cross-match it for 4-6 units.

      • Move the patient to the operating room.

      • If the bleeding cannot be controlled by pressure, clamp the common carotid artery as an emergency procedure after the blood pressure and pulse are within the reference range.

    • Definitive treatment for carotid artery rupture includes the following:

      • Ligate the carotid artery.

      • Avoid repair or diversion in an area of infection.

      • Use general endotracheal anesthesia.

      • Have adequate instrumentation ready.

      • Adequate exposure, both proximally and distally, to the source of bleeding and contaminated or infected areas helps avoid a second rupture.

      • Ligation is accomplished with a 1-0 silk suture that is reinforced, distally and proximally, with a 2-0 silk suture. The ligated stumps are then buried in the surrounding healthy tissue. Occasionally, ligating the carotid artery beneath the clavicle is necessary. Resection of the medial half of the clavicle is necessary for exposure if the ligation has to be performed inferior to the supraclavicular triangle.

    • Prophylaxis for carotid artery rupture includes the following:

      • Do not traumatize the carotid vessel. Adequate handling of the carotid artery and preservation of the adventitia are most important.

      • Avoid suction catheters that lie adjacent to the carotid artery.

      • If a fistula is present, it is diverted away from the carotid area.

      • Use adequate dressings that retain moisture.

      • Cover the carotid artery with a dermal graft using the levator scapulae or posterior scalene muscle.

      • Treat infection aggressively with drainage, culture, and appropriate antibiotics.

Outcome and Prognosis

Outcome

Radical neck dissection results include the following:

  • In a neck with negative histologic findings, the recurrence rate is 3-7%.

  • In a neck with positive histologic findings, the recurrence rate is 20-70%.

  • Extracapsular spread commonly is found in small nodes (25%) and large nodes (75%). The extracapsular spread can decrease survival by half and can decrease the disease-free interval.

  • Macroscopic extracapsular spread is associated with a recurrence rate of 45%, and microscopic extracapsular spread is associated with a recurrence rate of 25%.

  • Perineural and perivascular invasion are associated with more aggressive tumor behavior.

  • Involvement of the tumor margins carries a poor prognosis and a high risk of recurrent neck disease.

  • Patients with several involved nodes (≥ 4) have a worse prognosis than those with only one involved node.

  • Multiple levels of involvement are associated with a recurrence rate of 70%; only one level of involvement is associated with a recurrence rate of 35%.

Prognosis

In general, the characteristics of nodal metastasis that affect the prognosis in radical neck dissection include the following:

  • Extracapsular spread: This adversely affects the prognosis. The pathologist looks systematically for extracapsular spread, which is commonly encountered. Tumor spread beyond the capsule of a lymph node is the most important prognostic factor related to recurrence in the neck.

  • Perivascular and perineural invasion: Perineural and perivascular infiltration of the tumor is correlated with the risk of lymph node metastasis in the neck.

  • Sites of nodal involvement: The prognosis and survival rates are poor when multiple levels of neck nodes are involved. Posterior triangle and contralateral involvement is also an indication of poor prognosis.

  • Number of nodes: A greater number of involved lymph nodes portends a poorer prognosis. This leads to a higher risk of recurrence and a poorer survival rate.

  • Node fixation: Fixation is adherence to the surrounding structures. Adherence to the carotid artery or a muscle is an ominous sign. In general, fixation occurs with large masses and portends a poor prognosis.

  • Involvement of surgical margin: Positive surgical margins are common in advanced tumors and carry a poor prognosis.

  • Recurrent disease: Recurrent disease after surgical neck dissection is an ominous sign.

  • Degree of differentiation: The risk of cervical metastasis correlates with the grade of tumor differentiation at the primary site. Poorly differentiated tumors are more aggressive and carry a poor prognosis.

Future and Controversies

Controversies

Once the neck has metastatic disease, adequate treatment is essential. Preoperatively, no ideal method exists to identify metastatic disease clearly. Therefore, false-positive and false-negative results are common. Adequate treatment for metastatic neck disease has long been surgery, radiation therapy, or both.

In the last decade chemo/radiation therapy without surgery has been added to the armamentarium of treatment methodology for patients with head and neck cancer. This methodology includes treatment of the primary tumor as well as the neck metastasis. Patients who demonstrate persistence neck disease following this nonoperative approach are then being offered surgery in the form of salvage neck dissection.

In general, the management is not standardized and varies between institutions, geographical areas and surgeons. Initially, radical neck dissection was the operation used to control metastatic neck disease and an N0 neck. Now, head and neck surgeons agree that a radical neck dissection is not indicated in the absence of palpable neck metastasis or an N0 neck.

Modified radical neck dissection and selective neck dissection are adequate operations for palpable neck metastasis. The selection of a modified radical versus a selective neck dissection is controversial because the decision to preserve nonlymphatic structures remains an intraoperative surgical decision.

The N0 neck is a controversial subject. Many treatment choices exist, including whether to treat electively or to wait and observe, whether to perform surgery or radiation therapy, whether to operate on one side or both, and whether to use modified radical neck dissection or selective neck dissection. Indications need to be standardized.

Future

Future considerations in the management of neck metastasis include the following:

  • Develop better techniques for evaluation of neck metastasis.

  • Define and standardize the clinical criteria worldwide for a particular neck dissection.

  • Define and standardize indications for preoperative or postoperative radiation therapy of the neck.

  • Define and standardize indications for chemoradiation, before and after surgery.

  • Define and standardize indications for an N0 neck.

  • Define and standardize indications for an N+ neck.

  • Define and standardize the role of PET/CT in assessment and identification of neck metastasis.[27, 28]

  • Investigate and analyze the prognostic factors.

  • Continue clinical research in these areas.