Laryngeal cancer accounts for 1% of all new cancers diagnosed in the United States, with 12,290 new cases identified in 2009. More than 90% of laryngeal cancers are classified as squamous cell carcinoma (SCCA). This type of laryngeal cancer manifests
most often in men in the sixth to seventh decade of life. Although the male to female ratio is approximately 4:1, the incidence of SCCA in females is on the rise because of the increased percentage of women using tobacco. African American men are at higher risk for SCCA than white men (10.3 per 100,000 men compared to 6.1 per 100,000 men, respectively).1
Squamous cell carcinoma of the larynx is difficult to treat and manage. Health care professionals should be knowledgeable about the unique challenges faced by patients with laryngeal carcinoma in order to provide effective care. In particular, PAs must understand and document the unique anatomic alterations caused by surgical resection. Patients who undergo laryngectomy and their families require increased patience and support while adjusting to the lifestyle changes that result from this procedure.
ETIOLOGY
Tobacco is the number one risk factor for laryngeal carcinoma. Seventy-five percent of patients with head and neck cancer have a tobacco history. When tobacco use is combined with alcohol use, the risk for SCCA increases by more than 50%. The more cigarettes a person smokes, the higher his or her risk for squamous cell carcinoma becomes. Insufficient nutrition, poor dental hygiene, and exposure to carcinogens (asbestos and mustard gas) also increase the risk of laryngeal carcinoma.1 Current research shows a distinct link between the human papillomavirus (HPV) and SCCA. Recent studies of HPV 16 have indicated that HPV-positive tumors respond more favorably to treatment than HPV-negative tumors. Therefore, HPV 16 is a strong prognostic marker of improved survival in these patients.2
ANATOMY
Although the main function of the larynx is to enable phonation, it also serves as the divider between the respiratory and digestive tracts. It assists with protecting the airway from food and liquid bolus during swallowing. The larynx can be divided into three levels: the supraglottis, the glottis, and the subglottis. The glottis is made up of the true vocal folds. The supraglottis is the area from the tip of the epiglottis to the ventricles or the undersurface of the false cords. The subglottis extends inferiorly from about 1 cm below the vocal folds to the cricoid cartilage. Approximately 60% of laryngeal tumors are glottic with 35% and 1% being supraglottic and subglottic, respectively.1
While laryngeal tumors spread via the local lymphatic system, supraglottic tumors tend to spread bilaterally to cervical lymph nodes in zones II and III because of the rich lymphatic drainage system. Glottic SCCA can invade deep tissue; however, since the larynx itself has a limited lymphatic supply, less than 8% of patients with T1 and T2 tumors present with adenopathy. As a glottic tumor increases in size, the risk of lymphatic spread increases by 20% to 40%. Subglottic tumors normally spread superiorly to the glottis to the surrounding structures and sometimes to the paratracheal lymphatics.3
SYMPTOMS
Hoarseness is the most common symptom of laryngeal carcinoma. Patients with voice changes that persist for more than
3 weeks should be referred to an ears, nose, and throat (ENT) specialist. Other symptoms of SCCA include odynophagia, dysphagia, dyspnea, stridor, and hemoptysis. Any patient with unilateral ear pain of unknown etiology should undergo an ENT evaluation, as this pain may be referred from a tumor or could be a symptom caused by SCCA. Aspiration is common with laryngeal tumors as a result of changes on the vocal cords and should be evaluated with a modified barium swallow and a referral to a speech therapist.
DIAGNOSIS
Patients who have symptoms should be examined by an ENT head and neck surgeon. In the ENT office, flexible laryngoscopy is used to visualize the larynx and determine whether it is normal or contains cancerous lesions (Figure 1). Careful examination of the neck is also done to evaluate for cervical adenopathy. Direct laryngoscopy and surgical biopsy are then scheduled to determine a diagnosis and pathology. A complete diagnostic workup for staging includes CT of the neck with contrast (unless contraindicated), chest radiography, CT of the chest, and positron emission tomography (PET) to evaluate for metastatic lesions. Other testing may be required for patients with multiple medical problems. Laryngeal cancer is then classified into one of a number of stages based on factors such as symptoms or tumor locations. These stages are detailed online at http://www.cancer.gov/cancertopics/pdq/treatment/laryngeal/patient/page2.
TREATMENT
Treatment for laryngeal carcinoma is multidisciplinary and involves radiation oncologists, medical oncologists, and surgeons. This team of health care providers evaluates each patient's age, medical condition, tumor stage, and personal preferences. Using these factors, the team creates an individual treatment plan.
Nonsurgical options Early-stage laryngeal carcinoma is usually managed with radiation. Cure rates for patients with early-stage cancer who undergo radiation are 80% to 85% and up to 90% when chemotherapy is administered simultaneously.4 Some patients may be selected to undergo a partial laryngectomy. Patients with advanced disease are generally treated with a combination of radiation, chemotherapy, and surgery. To preserve the larynx, radiation and chemotherapy are usually attempted before surgery. However, this treatment option has multiple side effects and creates a higher risk of postoperative complications caused by the negative effects radiation may have on healing.
Surgical options Total laryngectomy is a treatment option reserved for patients with larger tumors or those whose tumors did not respond to radiation and who have persistent or recurrent disease. During total laryngectomy, the larynx is removed and the lower airway and upper digestive tract are separated; in particular, the trachea and pharynx become detached (Figure 2). The trachea is brought out to the surface of the skin, and a permanent stoma is created. The pharynx is primarily closed or else a flap is used to reconstruct the area. Patients who undergo this procedure will no longer have normal speech once the larynx has been removed. Five-year survival following total laryngectomy is 74% in patients with a T2 glottic lesion and 44% in patients with a T4 lesion.1