Vertical Partial Laryngectomy

Organ preservation therapy of the larynx is offered as a functional alternative to total laryngectomy. The intended goals of preservation therapy are to circumvent permanent tracheostomy, maintain laryngeal speech, and preserve swallow function. Subtypes of operations classified as organ preservation surgery of the larynx include the following: vertical partial laryngectomy (VPL), hemilaryngectomy, endoscopic cordectomy (including procedures that use lasers), and laryngofissure with cordectomy. This article focuses on the use of VPL in the treatment of early glottic cancers.

VPL is specifically designed to treat early T1 and T2 and select T3 laryngeal cancers. Despite initial local control and cure rates comparable with those of traditional radiotherapy (RT), VPL is largely reserved for patients with recurrent or persistent T1 and T2 disease for whom such therapy has failed. The intent of this article is to elucidate the clinical indications, contraindications, and technical points of interest that should be considered in connection with the use of VPL in early glottic cancer treatment.

Open transcervical vertical laryngectomy was initially proposed by Solis-Colen in 1869 to address early T1 and T2 and select T3 glottic cancer. With the advent of primary radiotherapy in the mid 20th century, open procedures were replaced as the definitive treatment for T1 and T2 disease. This was followed by the introduction of transoral laser excision (TLE), which has been popularized over the last 10 years and is considered a viable alternative to primary RT.

Classic hemilaryngectomy, in which the surgeon removes most of the thyroid cartilage on the side of a vocal cord cancer, produces variable speech and swallowing results. This problem led to the development of multiple reconstructive techniques. Among the various techniques used, the following have received particular attention: (1) false vocal cord pulldown, (2) cartilage preservation with perichondrial/sternohyoid muscle flap reconstruction, ^[1] and (3) epiglottic reconstruction for defects involving the anterior commissure. ^[2]

More sophisticated reconstructive methods have also been described, but no matter the method, the ultimate goal is maintaining normal laryngeal function. Selection of reconstructive technique partly depends on surgeon preference but is also dictated by the extent of resection required.

VPL is primarily an operation for early glottic carcinoma.

Frequency

Early carcinoma of the glottis is more common than early carcinoma of other head and neck sites because patients present with hoarseness relatively early in the course of the disease. Because radiotherapy is a well-established treatment for early glottic cancers with good oncologic and functional results, VPL is most often reserved as salvage surgery with the aim of removing the tumor with a cuff of healthy tissue. ^[3]

The etiology of glottic carcinoma correlates strongly with tobacco abuse, and most patients with the disease are smokers. Other etiologic factors include genetic predisposition and laryngeal papillomata. The roles of other carcinogens, such as viruses, chemicals, and inflammatory mediators, are being investigated. Some authors believe that gastroesophageal reflux disease may be a contributing factor.

Carcinoma of the larynx usually begins with dysplastic changes in the larynx, which then progress to carcinoma in situ, followed by microinvasion.

Patients with glottic carcinoma typically present with intermittent hoarseness of up to a few months' duration. A change from intermittent to constant hoarseness indicates vocal cord paralysis. In many cases, no other clinical findings are found in early glottic carcinoma other than hoarseness and indirect laryngoscopic findings of a laryngeal lesion. Early glottic cancer can manifest as leukoplakia (most common; found during examination) or as ulceration, polypoid changes, papilloma, or erythema. Consider all of these findings suggestive, particularly if found in patients who smoke.

Vertical partial laryngectomy (VPL) is indicated as both an initial therapy and as salvage therapy for early glottic cancer (T1 and T2 stages) that has been refractive to primary radiotherapy or transoral laser excision. In select cases, T3 lesions may also be addressed with this family of operations. However, it may not be appropriate in cases of recurrent glottic carcinomas, as they are often understaged and present with multiple foci of tumor throughout the larynx.

For T1 lesions that do not involve the anterior commissure, laser cordectomy can be performed. The false vocal cord reconstruction is then feasible using imbrication laryngoplasty. This operation facilitates false vocal cord reconstruction while maintaining the bulk of the neocord by transferring vascularized innervated false cord to oppose the contralateral true vocal cord. T2 lesions classified as such by impaired mobility are also appropriately addressed in this manner.

For T2 lesions that involve the supraglottis, the false vocal cord usually cannot be pulled down. If a VPL is selected, a different reconstruction technique, such as the perichondrial/sternohyoid muscle flap procedure or a muscle/free mucosal flap procedure, should be considered.

The larynx is located within the anterior aspect of the neck, anterior to the inferior portion of the pharynx and superior to the trachea. Its primary function is to protect the lower airway by closing abruptly upon mechanical stimulation, thereby halting respiration and preventing the entry of foreign matter into the airway. Other functions of the larynx include the production of sound (phonation), coughing, the Valsalva maneuver, and control of ventilation, and acting as a sensory organ.

For more information about the relevant anatomy, see Larynx Anatomy, Vocal Cord and Voice Box Anatomy, and Thyroid Anatomy.

See also Intraoperative details in the Treatment section.

Cancer that involves the anterior commissure, or is close to the Broyle ligament, makes tumor invasion of the thyroid cartilage more accessible. This risk has prompted some authors to question employing vertical partial laryngectomy (VPL) for such lesions in favor of a different organ preservation technique such as supracricoid partial laryngectomy (SCPL) with cricohyoidoepiglottopexy (CHEP) or cricohyoidopexy (CHP). Although voice results following SCPL are predictably worse than after VPL, some studies have shown the local control rates following SCPL are perhaps better for selected T2 and T3 lesions of the glottis. Each case should be individualized for the patient's particular tumor and preoperative function.

Some absolute contraindications to VPL exist. These include large T3 or any T4 lesions, arytenoid fixation, thyroid cartilage invasion, interarytenoid invasion, cricoarytenoid joint invasion, subglottic extension involving the cricoid cartilage, lesions that extend outside the larynx, and pre-epiglottic space invasion.

Because of the relative lack of lymphatics in the glottic division of the larynx, glottic cancers tend to metastasize only in advanced stages. A finding of nodal disease therefore indicates more advanced disease and is a relative contraindication to VPL.