The tissue that covers the vocal folds can turn into cancer. By far the most common cause of this is smoking. Just as the noxious chemicals in cigarette and cigar smoke irritate the lungs and cause lung cancer, they also affect the delicate covering of the larynx. After all, the smoke must go through the vocal folds to get to the lungs.
Hoarseness is the main sign of cancer of the vocal folds. The cancer cells form a mass that interferes with the closure of the vocal folds of vocal fold vibration and thus results in a hoarse voice. If it's ignored, the cancer grows into deeper tissues, causing progressively more damage to the larynx. It may result in a vocal fold paralysis, or get so large that it causes breathing difficulty. If allowed to grow unchecked, it can extend outside of the larynx and even into distant parts of the body. That's why hoarseness in a smoker that lasts more than a week or two should never be ignored. Caught early, vocal fold cancer may be curable without radical surgery. Allowed to grow, it can be deadly.
Cancer in the rest of the larynx, outside of the vocal folds, may grow to considerable size without causing any voice disturbance. Symptoms may include shortness of breath, cough that produces blood in the spit, a sensation of a mass or unexplained pain. A lump in the neck may be the first sign of trouble. Smokers should not hesitate to see a physician if they experience unexplained symptoms.
Treatment may include surgery, radiation or chemotherapy (medical therapy), each used alone or in combination with the others. The chances of cure depend on the size and extent of the lesion when it is discovered. Cancer of the larynx no longer automatically requires a laryngectomy (surgical removal of the larynx) for treatment, if caught early.
Of course, the safest way to deal with cancer is to minimize your chances of getting it in the first place. And that means stop smoking - now.