Supraglottic Cancer 

Updated: Mar 05, 2021
Author: Joshua D Hornig, MD, FRCSC; Chief Editor: Arlen D Meyers, MD, MBA 

Overview

Practice Essentials

Cancer of the supraglottis (supraglottic cancer) is almost exclusively squamous cell carcinoma (SCC), although SCC of the supraglottis is seen less frequently than cancer of the glottis and is treated differently from tumors of the glottis or subglottis. Because of its location, supraglottic cancer and its treatment can affect the function of the larynx, including speech, swallowing, and breathing. In workup, an accurate assessment of the anatomic extent of the tumor is needed, not only to select treatment modalities but also to compare therapeutic results of different modalities. Treatment options include surgery, radiation therapy, chemotherapy, or a combination thereof.

This article discusses the anatomy of the supraglottis, explains the staging of supraglottic lesions, and provides an overview of treatment options.

Signs and symptoms of supraglottic cancer

Patients with supraglottic cancer may present with the following signs and symptoms:

  • Persistent dysphagia
  • Odynophagia
  • Otalgia
  • Hoarseness
  • Hemoptysis
  • Stridor
  • Neck mass

Workup in supraglottic cancer

Clinical examination is notoriously inadequate for mapping tumor extent. Forty percent of diagnoses made based on clinical examination are inaccurate. Computed tomography (CT) scanning and magnetic resonance imaging (MRI) are useful studies in evaluating the spread of supraglottic lesions (see CT Scan of the Larynx). These modalities are also effective in measuring lymph node size; both can show areas of central lucency, which is consistent with tumor involvement.

Panendoscopy (ie, laryngoscopy, bronchoscopy, esophagoscopy, nasopharyngoscopy) has traditionally been the criterion standard for the diagnosis of second primary lesions. The examination is controversial, however; some argue that bronchoscopy and esophagoscopy have only a slightly increased yield over chest radiography and barium swallow and are thus not worth the risks associated with endoscopy.

Management of supraglottic cancer

Early and moderately advanced lesions are usually managed with supraglottic laryngectomy or radiotherapy. Advanced lesions are usually treated with total laryngectomy, preoperative or postoperative radiotherapy, and, possibly, chemotherapy, since combined-modality therapy produces better results than a single modality alone.

The classic supraglottic laryngectomy extends through the vallecula superiorly, the aryepiglottic folds posteriorly, the apex of the ventricle inferiorly, and the thyroid cartilage anteriorly.

The transoral use of the carbon dioxide laser has made it possible to avoid some of the complications that have traditionally excluded patients with pulmonary comorbidities from undergoing supraglottic laryngectomy. Studies have shown a rapid return of swallowing function and the virtual elimination of the need for tracheostomy when a supraglottic laryngectomy is performed transorally with a carbon dioxide laser.

Bilateral neck dissections are performed when treating patients with advanced disease, with occult metastases present as much as 62% of the time in patients with T3/T4 tumors.

History of the Procedure

During the past 150 years, the treatment of supraglottic tumors has progressed significantly. In 1852, Horace Green reported the first surgical resection of a laryngeal lesion, a polyp in the ventricle, removed under direct vision. By 1859, the first transcervical resection of an epiglottic neoplasm was reported. Chevalier Jackson revolutionized supraglottic surgery in 1915, when he used a laryngoscope and a punch biopsy to remove an epiglottic tumor.[1] Alonso first described conservation surgery for cancer of the supraglottic larynx in 1947, and, in 1958, Ogura formalized the procedure as the supraglottic laryngectomy.[2, 3] During the 1950s, the surgical microscope and endotracheal anesthesia were brought to bear on this disease. In the 1970s, the carbon dioxide laser began to be used for supraglottic tumors.

Epidemiology

Frequency

Laryngeal cancer is the second most common type of head and neck cancer worldwide.[4] In the United States, approximately 12,500 new cases are diagnosed each year. In 2002, approximately 160,000 cases of laryngeal cancer and 90,000 deaths were reported worldwide.[5]

Laryngeal cancer is the 11th most common cancer in men worldwide but is much less common in women. Men have been reported to have as much as 30 times the risk that women have for this disease. Older individuals are also at a higher risk for laryngeal cancer; the highest number of diagnoses is made in patients age 60-74 years.

The percentage of laryngeal cancers that originate in the supraglottis varies from country to country. In the United States, for example, approximately 30-40% of laryngeal cancers originate in the supraglottis, while most occur in the glottis. In Spain and Finland, however, the supraglottis is the most frequent subsite.[6]

Etiology

Generally, the international occurrence of SCC is proportional to tobacco and alcohol use. In societies in which tobacco is chewed rather than smoked, tumor location favors the oral cavity rather than the larynx.

Numerous studies have correlated smoking of tobacco products with SCC of the larynx. In fact, some studies have show that97% of patients with laryngeal cancer smoked. When compared with men who did not smoke, men who smoked at least 1.5 packs of cigarettes per day for more than 10 years were found to have a 30-fold increased risk of developing laryngeal cancer.

The risk for supraglottic cancer has been found to be higher with the use of black (air-cured) tobaccos than with the use of blonde (flue-cured) tobaccos. This difference is not found with glottic cancers, suggesting that the etiology for supraglottic cancers and glottic cancers may differ.[7]

Studies with controls for age, race, and smoking habits also suggest that consumption of alcohol increases the risk of laryngeal cancer. Alcohol consumption has been shown to have a synergistic effect with smoking; thus, the risk of developing carcinoma of the larynx is increased 100-fold in individuals who both smoke and drink. This may be partly due to the fact that alcohol serves as a solvent for the carcinogens of tobacco.

In 1946, Slaughter developed the theory of field cancerization in tumors of the head and neck.[8] In essence, this theory posits that the entire mucosa of the aerodigestive tract, when exposed to the same toxins, risks development of carcinoma. The vulnerable epithelium undergoes progressive changes that lead to malignancy as exposure to toxins continues. Hence, multiple areas of precancerous change can give rise to synchronous lesions. Supporting this theory is the high rate (4%) of synchronous lesions found upon workup of patients with lesions of the upper aerodigestive tract.

Dietary deficiencies, radiation exposure, human papillomavirus (HPV), and gastroesophageal reflux are other factors associated with laryngeal SCC.

Pathophysiology

The supraglottis is embryologically derived from the buccopharyngeal anlage in the region of the third and fourth branchial arches. The glottis and subglottis originate from the tracheobronchial anlage in the region of arches 5 and 6. Hence, the larynx virtually consists of 2 hemilarynges, each with different embryonal derivation and largely independent lymphatic circulation. Despite the theoretical separation of the supraglottis from the rest of the larynx, no anatomical or histological barrier has been identified. Furthermore, supraglottic tumors invading the paraglottic space have access to the glottis via the medial surface of the thyroid cartilage.

Lymphatic vascularity in the supraglottis is much denser than in the glottis and subglottis. This is important in the development of supraglottic cancer and leads to a significantly higher incidence of cervical lymph node metastases in tumors of this subsite.[9]

Presentation

Symptoms

Minimal changes in the vibration of the vocal cord due to tumor growth often cause dysphonia or hoarseness at an early stage in glottic cancer. Subglottic carcinomas can cause airway compromise at an early stage. Supraglottic cancers are less likely than glottic and subglottic cancers to produce noticeable symptoms such as these early in the disease course and are more likely to present with the less specific symptoms of persistent dysphagia, odynophagia, or otalgia.[4] Patients with SCC of the supraglottis are not limited to these symptoms, however, and may also present with hoarseness, hemoptysis, stridor, or chronic cough. Patients with SCC of the supraglottis are more likely to present with a neck mass, partly because patients with supraglottic cancer generally present later than patients with glottic cancer, and partly because of the differences in anatomy and lymphatic drainage,

Examination

Due to the fact that supraglottic patients with SCC often present with nodal disease, palpation of the neck is important. Physical examination may reveal laryngeal or cervical findings.

Examination with a laryngeal mirror or a flexible nasopharyngoscope aids in visualization of supraglottic lesions.

Relevant Anatomy

The supraglottic larynx is partitioned into 4 subdivisions, as follows: (1) aryepiglottic folds, (2) arytenoids, (3) false cords, and (4) epiglottis. For tumor-staging purposes, the epiglottis is further subdivided into suprahyoid and infrahyoid regions. These areas of the supraglottis are structured within the framework of the supraglottic larynx, which includes the upper half of the thyroid cartilage, the arytenoid cartilages, and the epiglottis. In the image below the vocal fold, epiglottis, aryepiglottic fold, and arytenoids are seen.

A surgical specimen after laryngectomy. The arrow A surgical specimen after laryngectomy. The arrow points to the vocal fold. Note the epiglottis, aryepiglottic fold, arytenoids, and false folds superior to the arrow.

Supraglottis subsites

See the list below:

  • Suprahyoid epiglottis (lingual and laryngeal surfaces)

  • Infrahyoid epiglottis

  • False cords

  • Arytenoid

  • Aryepiglottic folds

Supraglottic squamous cell carcinoma (SCC) follows a predictable pattern of spread. Although tumors may extend inferiorly to involve the vocal folds and subglottis, invasion more often occurs in adjacent sites outside the larynx such as the base of tongue, vallecula, pyriform sinus, and postcricoid region. As the disease progresses, tumors of the supraglottis tend to metastasize to regional lymph nodes.

 

Workup

Laboratory Studies

No specific laboratory studies are necessary for the workup of patients with supraglottic cancer. However, a number of tests may be indicated to evaluate the general health of these individuals.

Imaging Studies

 

An accurate assessment of the anatomic extent of the tumor is needed, not only to select treatment modalities but also to compare therapeutic results of different modalities. For example, cancer that extends through a boundary, such as the thyroid cartilage or pyriform apex, demands more aggressive treatment than a lesion without such extension. Clinical examination is notoriously inadequate for mapping tumor extent. Forty percent of diagnoses made based on clinical examination are inaccurate. As a result, radiographic assessment is important in the pretreatment workup of patients with laryngeal cancer.

Imaging studies help to define spread to the preepiglottic space (which characterizes T3 carcinoma) and also help to define thyroid cartilage invasion or extralaryngeal submucosal extension (which characterizes T4 carcinoma).

CT scanning and MRI are useful studies in evaluating the spread of supraglottic lesions (see CT Scan of the Larynx), helping to assess involvement of the base of tongue and spread to regional lymph nodes.

Both the preepiglottic and paraglottic space contain mostly fat; hence, CT scans with contrast or MRI scans, especially T1-weighted images, show tumor infiltration into these areas.

Having been shown superior to clinical examination in demonstrating positive lymph nodes, CT scanning and MRI can help to gauge cartilage invasion and help define metastatic spread to the neck.

MRI and CT scans are useful in measuring lymph node size; both can show areas of central lucency, which is consistent with tumor involvement.

Although MRI is somewhat superior with respect to soft-tissue contrast resolution, CT scanning has a faster imaging time, which can reduce motion artifact.

Diagnostic Procedures

 

To obtain tissue diagnosis and help assess the extent of the disease, direct laryngoscopy is often performed in the operating room.

Videostroboscopy can be helpful in detecting subtle infiltration of the vocal folds.

Panendoscopy (ie, laryngoscopy, bronchoscopy, esophagoscopy, nasopharyngoscopy) has traditionally been the criterion standard used to diagnose second primary lesions. Panendoscopy is controversial, however. Some argue that bronchoscopy and esophagoscopy have only a slightly increased yield over chest radiography and barium swallow and are thus not worth the risks associated with endoscopy. This controversy notwithstanding, most practitioners would agree that direct laryngoscopy, usually under anesthesia, is essential for staging purposes and in obtaining biopsy samples necessary for tissue diagnosis. In the image below laryngoscopic view of the larynx can be seen.

Laryngoscopic view of the larynx. Note the followi Laryngoscopic view of the larynx. Note the following supraglottic structures: epiglottis, aryepiglottic folds, arytenoids, and false folds.

If intraoperative laryngoscopy and biopsy is not appropriate, ultrasonography-guided fine needle aspiration of endolaryngeal advanced supraglottic carcinomas can be performed in the clinical setting without any preparation. According to Lopchinseky et al, this allows for a rapid diagnosis and does not have the costs, side effects, or risks of a direct laryngoscopy.[10]

Histologic Findings

The mucosa of the supraglottis is composed of nonkeratinizing, stratified, squamous epithelium. Inferiorly, at the level of the laryngeal aditus, this epithelium changes to ciliated, pseudostratified, columnar epithelium at the false folds and the ventricle.

Squamous cell carcinoma (SCC) is classified as well-differentiated, moderately differentiated, or poorly differentiated. Histological findings include anaplastic-appearing cells below the basement membrane with a variable degree of keratin products and intracellular bridges. Microscopic view of squamous cell carcinoma is seen in the image below.

Histological specimen of squamous cell carcinoma ( Histological specimen of squamous cell carcinoma (SCC).

Staging

Staging of tumors of the supraglottis follows the 2003 definitions of the tumor, node, metastases (TNM) classification elaborated by the American Joint Committee on Cancer and the International Union Against Cancer.

Supraglottic cancer T staging

Stages are designated as follows:

  • Tis - In situ
  • T1 - Limited to 1 subsite with normal cord mobility
  • T2 - Invades mucosa of more than 1 adjacent subsite of supraglottis or glottis or region outside the supraglottis, without fixation of the larynx
  • T3 - Limited to larynx with vocal cord fixation and/or invades the postcricoid area, pre-epiglottic tissues, paraglottic space, and/or minor thyroid erosion
  • T4a - Invades through the thyroid cartilage and/or invades tissues beyond the larynx
  • T4b - Invades prevertebral space, encases carotid artery, or invades mediastinal structures

Node status in supraglottic cancer

Status is designated as follows:

  • N0 - No nodes
  • N1 - Metastasis in a single ipsilateral node that is greater than or equal to 3 cm
  • N2a - Metastasis in a single ipsilateral node more than 3 cm but not more than 3-6 cm in greatest dimension
  • N2b - Metastasis in multiple ipsilateral nodes with none more than 6 cm in greatest dimension
  • N2c - Metastasis in bilateral or contralateral nodes, none more than 6 cm in largest dimension
  • N3 - Metastasis in a lymph node that is larger than 6 cm in greatest dimension

Table. Staging of Supraglottic Cancer (Open Table in a new window)

Stage

Tumor Spread

Node Involvement

Distant Metastases

Stage 0

Tis

N0

M0

Stage I

T1

N0

M0

Stage II

T2

N0

M0

Stage III

T3

N0

M0

T1

N1

M0

T2

N1

M0

T3

N1

M0

Stage IVA

T4a

N0

M0

T4a

N1

M0

T1

N2

M0

T2

N2

M0

T3

N2

M0

 

T4a

N2

M0

Stage IVB

T4b

Any N

M0

 

Any T

N3

M0

Stage IVC

Any T

Any N

M1

 

 

Treatment

Medical Therapy

Radiation therapy

Cancers of the supraglottis commonly manifest in patients who are debilitated from years of smoking and drinking. Because of the high surgical risk in some of these patients, radiation therapy can be a better option than surgery. Treatment options involving radiotherapy are numerous, as protocols differ in dose, extent, and fractionation.

Comparing results of supraglottic laryngectomy with those of radiotherapy is difficult because some series of patients treated with radiotherapy alone include those with lesions that were anatomically unsuitable for conservative laryngeal surgery. In addition, patients treated with radiotherapy tend to be those whose medical conditions contraindicate surgical modalities. Both of these factors seem to bias a comparison against radiation therapy. Remember, however, that patients in whom radiation therapy fails have the option of surgical salvage, which increases overall survival rate for patients treated with definitive radiation therapy.

Primary radiotherapy is accepted as appropriate treatment for early stage disease.[11] Current recommendations for the use of radiation therapy in advanced disease, however, advocate the addition of platinum agents, particularly cisplatin, to radiation therapy when nonsurgical treatment is chosen.

Adjuvant radiation therapy has become highly recommended in patients whose tumor pathology suggests a high risk for recurrence, such as those with high-grade tumors or extracapsular spread. Postlaryngectomy patients are more commonly undergoing radiotherapy even without these risk factors, because of the propensity of supraglottic cancers for occult metastasis.

Role of chemotherapy

In the early 1990s, a landmark trial conducted by the Department of Veterans Affairs demonstrated that, in some patients, induction chemotherapy followed by radiation therapy allowed for preservation of the larynx while maintaining the same survival rates achieved with surgery followed by adjuvant radiation therapy.[12] The regimen used in this trial, cisplatin plus 5-FU followed by radiation therapy, has been used by many as an alternative to laryngectomy in patients with advanced disease. Single agent cisplatin given concurrently with radiation therapy has since been shown to be more effective and better tolerated and is currently considered the standard when nonsurgical definitive treatment is chosen.[11, 13] Cisplatin has been shown to enhance the effects of radiation on tumor cells, which is a likely explanation for the superiority of concurrent administration versus sequential administration.

Trials that compare larynx preservation regimens consisting of chemoradiation with those with radiation therapy alone have shown that chemotherapy adds the additional benefit of reducing the rate of distant metastasis. Currently ongoing trials are examining the usefulness of adjuvant chemotherapy regimens, as well as the use of some of the newer biologic agents in patients with various stages of this disease.

Various combinations of cytotoxic chemotherapy have been used for palliation of disease. SCC of the larynx often responds to chemotherapy in this setting, although it has not been shown to be effective in cure.

Surgical Therapy

Decisions regarding proper management of primary supraglottic carcinoma remain controversial despite advances in radiotherapy and surgical procedures. Of the common treatment modalities, none have shown an advantage in overall survival.[14]

The goal of treatment for supraglottic cancer is cure of disease, with preservation of speech, when possible. Treatment options include surgery, radiation therapy, chemotherapy, or a combination thereof. The selection of treatment modality relies on many factors: tumor size, clinical stage, the patient's overall medical condition, the philosophy and experience of the physician, and the patient's choice.

Early and moderately advanced lesions are usually managed with supraglottic laryngectomy or radiotherapy. Advanced lesions are usually managed with total laryngectomy, preoperative or postoperative radiotherapy, and, possibly, chemotherapy, since combined-modality therapy produces better results than a single modality alone.

The propensity of supraglottic lesions to spread to the cervical nodes should be kept in mind when treatment options for this disease are considered.[15] A retrospective study by Yilmaz et al indicated that in cases of lateral supraglottic cancer, the rate of occult contralateral lymph node metastasis is high enough to warrant routine bilateral dissection even when midline crossing is minimal or absent. The study, which involved 305 surgically treated patients with T1-3 squamous cell carcinoma (SCC) of the supraglottis, found the rates of occult and overall metastasis to be 16% and 28%, respectively, with the degree of midline crossing having no statistically significant association with the rate of contralateral neck metastasis.[16]

Supraglottic laryngectomy versus total laryngectomy

The traditional treatment for SCC of the larynx is laryngectomy. The classic supraglottic laryngectomy extends through the vallecula superiorly, the aryepiglottic folds posteriorly, the apex of the ventricle inferiorly, and the thyroid cartilage anteriorly. Included in the resection are the hyoid bone, epiglottis, superior half of the thyroid cartilage, aryepiglottic folds, and the false folds to the arytenoids. Occasionally, one or both arytenoid cartilages are removed. If surgery is selected as the primary treatment of supraglottic carcinoma, many believe that transcervical partial laryngectomy is the surgical therapy of choice for T1 and T2 lesions, while lesions that are more extensive (eg, T3, T4) demand total laryngectomy. Transcervical supraglottic laryngectomy, however, can be performed on T3 lesions, provided no true vocal fold involvement exists.

Contraindications for transcervical supraglottic laryngectomy include tumors that extend to the interarytenoid space, postcricoid mucosa, and true vocal folds. Additionally, tumors that cause cord fixation are a contraindication for supraglottic laryngectomy. Because aspiration is an issue in patients after supraglottic laryngectomy, patients with poor pulmonary function would be more appropriately treated with total laryngectomy or transoral supraglottic laryngectomy.

A literature review by Lechien et al indicated that early stage supraglottic cancer can be effectively treated with supraglottic laryngectomy via transoral robotic surgery (TORS). Patients in the study had cT1-, cT2-, or cT3-stage tumors, with 24-month local and regional control rates ranging from 94.3% to 100% and 87.5% to 94.0%, respectively, and 2- and 5-year overall survival rates ranging from 66.7% to 88.0% and 78.7% to 80.2%, respectively.[39]

Laser surgery

The carbon dioxide laser is useful because of its hemostatic effects and precise tissue ablation. Consequently, the carbon dioxide laser has become an option for addressing T1 and T2 lesions transorally to avoid transcervical supraglottic laryngectomy.[17, 18, 19, 20, 21, 22]

Carbon dioxide laser surgery is performed with a spreadable laryngoscope. The laser is used as a cutting instrument and not used to vaporize tumor. Small tumors of the epiglottis and aryepiglottic folds are excised with a 1-cm margin as an excisional biopsy. In large tumors of the suprahyoid epiglottis, vertical division of the epiglottis facilitates resection. An incision is then made, guided by the valleculae, until the hyoid bone is reached and exposed. The incision continues caudal from the hyoid toward the thyrohyoid membrane until the upper border of the thyroid cartilage is reached. The entire preepiglottic space is then removed along the inner surface of the lamina of the thyroid cartilage toward the anterior commissure of the vocal fold. False cord tumors are excised similarly. Resection includes the preepiglottic space if the infrahyoid epiglottis is invaded and the preepiglottic space and paraglottic space if the false cords are involved.

The transoral use of the carbon dioxide laser has made it possible to avoid some of the complications that have traditionally excluded patients with pulmonary comorbidities from undergoing supraglottic laryngectomy. Studies have shown a rapid return of swallowing function and the virtual elimination of the need for tracheostomy when a supraglottic laryngectomy is performed transorally with a carbon dioxide laser.

A recent Phase II study conducted by the Southwest Oncology Group (SWOG) confirmed the relative safety and efficacy of this procedure when used in conjunction with postoperative radiation therapy in patients with Stage I, II, and III disease.[23] Cabanillas et al performed a study that showed similar benefits when transoral laser supraglottic laryngectomy was compared with a traditional transcervical approach in patients with T1 or T2 supraglottic tumors.[24] Assessment of the oncologic results of numerous series indicates that both the survival and local recurrence rates associated with transoral laser resection are comparable with those seen in patients who undergo traditional transcervical partial laryngectomy.

These results combined with those of other studies demonstrate that supraglottic laryngectomy can be a reasonable option not only in the typical patient but also in patients with pulmonary comorbidities.

Elective neck dissection

Long-term survival for patients with SCC of the supraglottic larynx is most dependent on the successful management of neck disease.[25, 26] This is partially due to occult metastasis found on neck dissection in patients with carcinoma of the supraglottis is more common than in the other laryngeal subsites. Occult metastases are present approximately 16% of the time in patients with T1/T2 tumors and have been reported to be present as much as 62% of the time in patients with T3/T4 tumors. Because of this, bilateral neck dissections are performed when treating patients with advanced disease. Many institutions perform bilateral neck dissections on patients with any nodal stage;[27] however, evidence suggests that a less extensive neck dissection may be adequate in patients with N0 disease.[28]

Complications

Complications of treatment for supraglottic carcinoma largely depend on the therapeutic modality selected to treat the disease. For example, complications of radiotherapy include xerostomia, dysphagia, hoarseness, excessively thick mucous secretions, chondronecrosis of the larynx, transverse myelitis, and laryngeal edema with airway obstruction.

Patients who undergo supraglottic laryngectomy have a high incidence of aspiration, approximately 40-70%. Postoperative alteration of swallowing function is caused by disruption of the superior laryngeal nerves. Because of the high incidence of postoperative aspiration, some patients with poor pulmonary function are better served by nonsurgical therapy, total laryngectomy, or transoral supraglottic laryngectomy.

The transoral use of the carbon dioxide laser can reduce the incidence of aspiration because this technique does not involve disruption of the superior laryngeal nerves and, therefore, has a less deleterious effect on swallowing function. This makes supraglottic laryngectomy an option for some patients who have not been considered candidates for surgery in the past. Remember, however, that patients undergoing laser surgery may have an increased risk for bleeding and vestibular stenosis.

A study by Carta et al of patients with supraglottic SCC who underwent transoral carbon dioxide laser supraglottic laryngectomy found that in patients who were treated with a modified type IVb version of the procedure—in which the inferior third of the arytenoid cartilage, if it had no direct tumor involvement, was spared—long-term swallowing function was significantly better than in patients in whom the entire arytenoid was resected.[29]

An additional complication seen in surgical patients, especially those with prior radiation therapy, is fistulous tract formation. The incidence of pharyngocutaneous fistula is also greatly reduced by using transoral laser surgery instead of transcervical resection.

Outcome and Prognosis

The survival and prognosis of patients with laryngeal cancer has been shown to differ based on subsite.[30] Supraglottic cancers have a worse prognosis than glottic cancers and are also more likely to be high-grade cancers. Supraglottic cancers have few initial symptoms; thus, they are often discovered later than cancers of the glottis and subglottis. Later presentation leads to a greater likelihood that the cancer has spread outside of the capsule or spread to regional lymph nodes. The presence of extracapsular spread and regional lymph node metastases are the 2 most significant negative prognostic indicators in supraglottic cancer.[31, 32] Tumors with extracapsular spread and regional metastases indicate a lower survival rate and a higher recurrence rate. High-grade tumors are also a factor associated with decreased survival.

Five-year overall survival for supraglottic cancers in general is reported to be between 40-50%. Using the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) database, Patel et al, in a study of 22,675 cases of primary supraglottic SCC, found an overall 5-year disease-specific survival (DSS) rate of 54.0%.[33]

When broken down by cancer stage, the 5-year overall survival rate can vary significantly—from up to 82% in stage I disease to 45% or lower for stage IV disease.

Analysis of the SEER database, however, showed that the 5-year overall survival for patients with laryngeal cancer decreased over a matter of decades.[34] This reduction in survival corresponded with a change in treatment patterns in the 1990s that saw an increase in nonsurgical treatment of laryngeal cancer.[35] Although the reasons for the decline in survival are unknown, a change in treatment patterns likely played some role;[36] the treatment selection for patients with laryngeal cancer must be considered carefully, and, in patients with supraglottic SCC, the more aggressive behavior of the disease in comparison with glottic cancer should be kept in mind.

A retrospective study by Elegbede et al indicated that patients who undergo nonsurgical treatment for stage III or IV SCC of the supraglottis have a higher rate of disease recurrence than do those who undergo surgical treatment but that the two groups have a comparable overall survival rate. The study, which included 97 patients who underwent surgical treatment and 138 who were treated with nonsurgical therapy, found the 5-year freedom-from-recurrence rates for the surgical and nonsurgical patients to be 75% and 55%, respectively, while the 5-year overall survival rate was 52% for both groups.[37]

As associated with treatment modality, the Patel study reported that the best 5-year DSS rate occurred in patients who underwent surgery alone (64.2%), although patients with American Joint Committee on Cancer stage IV disease fared best with a combination of surgery and radiation therapy (5-year DSS rate = 52.5%).[33]

In the Elegbede study, laryngeal preservation was achieved in 83% of the nonsurgical patients, compared with 42% of the surgical group. In addition, over the course of the study’s 5-year follow-up period, voice function values were better in the nonsurgical patients, while swallowing function scores were similar in the surgical and nonsurgical groups.[37]

Future and Controversies

The diagnosis and treatment of supraglottic cancer has progressed greatly over the past 150 years. Surgical procedures, such as the supraglottic laryngectomy and laser excision, have allowed surgeons to remove tumors with less morbidity. Radiotherapists have developed better protocols and techniques to administer radiation to more precise anatomical fields. Chemotherapy is being used to protect laryngeal function through organ sparing protocols.

In the future, further refinements in diagnostic and therapeutic techniques will allow physicians to better treat patients with laryngeal cancers. Positron emission tomography (PET) scans may help diagnose lesions earlier and more accurately assess recurrence. Working with improved vectors and a better knowledge of the molecular biology of cancer may afford patients better treatment with fewer adverse effects using gene therapy.

 

Guidelines

Guidelines Summary

A laryngeal cancer guideline released in 2016 under the United Kingdom National Multidisciplinary Guidelines included the following recommendations for supraglottic cancer[38] :

  • Radiotherapy, transoral laser microsurgery, and transoral robotic surgery are reasonable treatment options for T1-T2 supraglottic carcinoma
  • Supraglottic laryngectomy may have a role in the management of selected tumors
  • Most patients with T3 supraglottic cancers are suitable for nonsurgical larynx preservation therapies