OncoLog Volume 54, Number 01, January 2009

Compass , a quarterly supplement to OncoLog , discusses cancer types for which no standard treatment exists or more than one standard treatment is available. Our goal is to help readers better understand the nuances of management for such diseases and the variables that M. D. Anderson specialists consider when counseling patients about treatment alternatives.

Winter 2009

Early-Stage Laryngeal Cancer Definitive Treatment Options That Spare Function

By Sunni Hosemann

The subglottis comprises the throat tissue below the glottis that leads to the pharynx. As do lesions of the supraglottis, sub- glottic neoplasms often develop without early symptoms and tend to be more advanced on presentation than glottic lesions. According to the National Comprehensive Cancer Net- work, 60%–65% of laryngeal cancers occur in the glottis, 30%–35% occur in the supraglottis, and about 5% occur in the subglottis. The majority are squamous cell carcinomas, arising from the tissues covering the structures in the larynx. Initial evaluation When a patient presents with a laryngeal neoplasm, careful evaluation by a multidisciplinary team is necessary. The pretreat- ment workup includes a comprehensive physical examination, laboratory and imaging studies, and an endoscopic examination of the larynx to fully assess the extent of the tumor. At M. D. Anderson, the evaluation also includes laryngeal videostroboscopy, an endoscopic procedure in which video and sound recordings of the larynx are made while the patient vo- calizes specific sounds. Videostroboscopy uses stroboscopic illumination that gives the impression of a slow-motion view when the recording is played, allowing the examiner to visual- ize the vibration of the vocal folds during phonation. Video- stroboscopy provides a dynamic image of how the vocal folds close and the symmetry of structure and movement. It can also identify vibratory abnormalities that may not be visible to the naked eye, giving important information about the extent to which the tumor has invaded the vocal folds. “This informa- tion often helps predict the potential for retaining normal voice and voice quality after the cancer treatment,” said Jan S. Lewin, Ph.D., an associate professor in the Department of Head and Neck Surgery and director of the Section of Speech Pathology and Audiology. Laryngeal videostroboscopy and analysis of sound produc- tion are routine assessments for patients with tumors in the larynx. The examinations are performed at baseline, before treatment begins, and after treatment has been completed. Sometimes, the tests are also performed during treatment to help monitor the patient’s response to treatment and the effect of treatment on vocal function. In any case, videostroboscopy and laryngeal function tests provide important information that helps determine the cancer treatment that will best pre- serve function in the long term. The tests help clinicians pre- dict the effects of cancer treatment and identify rehabilitative strategies that will best preserve the voice, Dr. Lewin said.

Introduction A patient who develops laryngeal cancer has a great deal at stake in terms of speech and swallowing function and thus quality of life. Fortunately, when laryngeal cancer is detected early, the patient has treatment options that can effectively control the disease, often without causing a significant loss of function. Early-stage laryngeal cancer is defined here as a tumor that is confined to the larynx and has not invaded adjacent struc- tures or spread to lymph nodes in the neck. The current stan- dard treatment for such tumors is partial laryngectomy or radiation therapy. While both approaches provide similar medical outcomes, individual patients may find one approach more suitable than the other. Understanding the larynx The larynx is a delicate organ. “It has a complex, layered microanatomy of nerves and muscles that help it move in ex- quisite ways,” explained F. Christopher Holsinger, M.D., an assistant professor in the Department of Head and Neck Sur- gery at M. D. Anderson. The larynx’s intricate and complex arrangement of cartilage and muscle is responsible for voice and also partly for breathing. Additionally, the organ’s sphinc- ter makes swallowing possible, prevents aspiration, and stabi- lizes the thorax by shutting against exhalation during lifting. The three anatomic areas of the larynx—the glottis, supra- glottis, and subglottis—have differences in physical makeup, function, and lymphatic drainage. Accordingly, the symptoms of laryngeal lesions tend to vary depending on their location, as do the treatment and prognostic implications. The glottis, the midsection of the larynx, contains the true vocal cords. Glottic lesions cause easily recognized symptoms, the most common being hoarseness. Because of that and be- cause the area has relatively little lymphatic drainage, neo- plasms in the glottis are often found at early, curable stages, before they have spread to lymph nodes. The supraglottis, located above the glottis, contains the in- tricate muscle fibers that control the vocal cords; this area also includes the epiglottis, a cartilaginous flap that protects the airway by closing during swallowing. Supraglottic lesions often do not produce early symptoms. These lesions are also close to a rich lymphatic network, and many patients with supraglottic lesions present with lymph node involvement.

4 OncoLog • January 2009

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