What is laryngeal cancer?
Laryngeal cancer, like other cancers, is a change of normal tissue to tissue that grows uncontrollably. Laryngeal cancer begins at the surface of the larynx, in the cells of the mucosa . If unchecked, laryngeal cancer spreads into deeper tissues, to the neck outside of the larynx and eventually to other parts of the body, principally the lungs.
Smoking is responsible for the overwhelming majority of laryngeal cancers. The tissue changes and irritation from smoking are aggravated by the effects of alcohol, so that the effects of the two together are greater than each one separately. Laryngeal cancer in nonsmokers is a rarity.
What are the symptoms of laryngeal cancer?
Symptoms depend on the location of the cancer. If it grows on the vocal fold, cancer causes hoarseness, even when it is quite small. Most hoarseness, particularly in nonsmokers, is caused by benign lesions. Nevertheless, because effective cure depends on early diagnosis, hoarseness that lasts beyond two weeks should be brought to the attention of their doctor. Smokers are often hoarse for other reasons (for example, Reinke’s edema), and may postpone a visit to the doctor’s office.
Cancers elsewhere in the larynx generally grow to a larger size before they cause symptoms, since these tissues are not involved in voice production. The first sign of such a cancer may be a bloody cough, or noisy or difficult breathing caused by the bulk of the tumor.
What does laryngeal cancer look like?
Laryngeal cancers are generally erosions or growths on the surface of the larynx. These may be white or red in appearance, and they vary in size and location. Unlike most benign lesions, cancers usually have a rough, irregular surface and may bleed from time to time. They may appear anywhere along the length of the vocal folds, as well as on other parts of the larynx.
Figure 1: A cancer of the right vocal fold (left in the image) is a bulky ovoid mass with an irregular white surface.
Because it grows into normal tissues, cancer of the vocal fold impairs the vibration of the mucosa. Stroboscopy can be very useful to assess the integrity of the vibratory tissue, and may help distinguish between a cancerous and a benign lesion. The stroboscopic exam needs to be interpreted carefully, however. Ultimately, only examining tissue under the microscope can yield a definite diagnosis, so lesions with suspicious features should undergo microlaryngoscopy and biopsy.
Figure 2: Vocal cord cancers often appear white because of the accumulation of dead cells, called “keratin” on the surface.
How is laryngeal cancer treated?
Generally, radiation alone is used for small lesions confined to the larynx. Radiation has yielded equivalent cure rates with less vocal disability than surgery. Surgery was the preferred treatment years ago, and is now being examined again in view of refinements of surgical technique.
With larger tumors of the larynx with or without cancer in the neck, radiation is combined with chemotherapy, and sometimes followed by surgery to remove any disease which may be left. In this way, laryngectomy can be avoided more often than it could in the past. Large, bulky tumors may still require surgical removal or at least surgery to open an airway prior to any additional treatment.
Figure 3: Cancers arise from precancerous lesions called “Leukoplakia” or “white plaque.” This patient has leukoplakia of both vocal folds. Biopsy revealed cancer in one part of the leukoplakia on the left vocal fold.
Once laryngeal cancer has traveled out of the neck (most commonly, it goes to the lungs), it generally is not curable. However, slowing down the disease is possible using chemotherapy and occasionally radiation.
More information is available from the National Cancer Institute.