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Introduction
 Cancer of the larynx or voice box, while not a common disease, does
account for from 2 to 5 percent of all cancer cases. The outcome of this
form of cancer is almost entirely dependent on how early it is
discovered and treatment begun. If diagnosed early, when the cancer is
commonly limited to one vocal cord, the disease can be cured. In the
great majority of such cases, a normal voice will be obtained.
In the disease's later stages, however,
when the cancer has spread to other areas of the larynx and throat,
treatment often involves laryngectomy, the surgical removal of the
larynx.
Cancer of the larynx like other
cancers, is characterized by an unchecked multiplication of cells which
build up into an invasive tumor. As the tumor develops, the cancer
spreads, not only to adjacent tissue areas, but to distant parts of the
body as well, using the lymph ducts and blood vessels for passage. These
new, related growths are called metastases and the spreading cancer is
said to have metastasized. Eventually the tumors interfere with vital
body functions and if left uncontrolled will kill the patient.
Those It Strikes
Several environmental or occupational factors have been linked with
laryngeal cancer. Habitual smoking and heavy drinking are among the most
important of these.
Cancer of the larynx occurs more
frequently among city dwellers than among persons living in rural areas.
The ratio of urban to rural case for laryngeal cancer is similar to that
for cancer of the lung or bronchus.
Other environmental factors that have
been occasionally associated with cancer of the larynx are voice strain,
as experienced by singers, actors, and ministers, exposure to wood and
metal dusts, and repeated inhalation of some chemical substances. The
disease, keratosis, which produces wart-like growth on the larynx, is
believed to be a pre-cancerous condition and those with the disease
should be examined regularly by a physician.
Diagnosis and Symptoms
An important reason for the encouraging prognosis that can be made
for many cases of laryngeal cancer is the fact that symptoms usually
occur at a stage of the disease when the tumor is small and localized,
However, the relative mildness of most of those symptoms is often
misleading and frequently the warning signs are not heeded until late.
One of the most common early symptoms
of laryngeal cancer is a prolonged hoarseness. Any hoarseness lasting
for more than three weeks should be investigated by a physician.
Hoarseness in cancer of the larynx is a direct result of a tumor on the
vocal cords, the most common early site of the disease. But often, early
growths occur elsewhere on the larynx, causing such symptoms as a change
in voice pitch, lump in the throat, coughing, difficulty and pain in
breathing or swallowing, and even earache. In these instances,
hoarseness may not develop until much later, if at all.
A relatively simple preliminary
examination for laryngeal cancer can be made by the physician in his
office using the laryngeal mirror. This device resembles a dentist's
mirror with a long handle. A physician using this mirror can detect most
tumors of the larynx. However, further direct examination under local
anesthesia may be necessary. If he suspects cancer, the physician will
need to take a biopsy or specimen of the suspected tumor to be examined
under a microscope to confirm the presence of cancer cells. X-ray and
fluoroscopic examination are also often used to determine the actual
size, extent, and effect of the tumor. The discovery of the exact site
of the primary and metastasizing lesions in laryngeal cancer is of great
importance to the scheduling of an advisable treatment program.
Treatment
In selecting a course of treatment for laryngeal cancer, the physician's
aim is to cure the cancer while preserving the maximum degree of speech.
As in most other cancers, the two main
types of treatment are irradiation and surgery. Most investigators and
clinicians in the field agree that irradiation is probably the best
treatment for the early, confined laryngeal lesion producing a minimum
of aftereffects. Surgery or a combination of surgery and radiation, is
generally used for the more advanced laryngeal cancers.
It must be emphasized that the correct
treatment for the individual is dictated by the particular
characteristics of his case, especially the site, size, and extent of
the tumor as well as the patient's general health. A collaboration
between radiotherapist and surgeon is desirable to evaluate these
factors and prescribe the proper program of treatment.
In two-thirds of the cases of laryngeal
cancer the patient is able to retain the larynx, but again, early
treatment is essential. In addition, there is a definite need for
regular follow up examinations to check for recurrence or metastases.
During the past 15 years there has been an upward trend in survival for
cancer of the larynx patients. More than half of these live 5 years or
more after diagnosis. This improvement in survival rates seems to be the
result of earlier detection and more effective treatments. Over 80
percent of these patients whose cancer was detected early and treated
surgically survived five years after diagnosis and nearly three out of
four survived ten years.
Rehabilitation
If laryngectomy is the necessary form of treatment most patients can
learn to speak again through a technique known as esophageal speech.
This "substitute" speech is
produced by expelling swallowed air from the esophagus. A well-trained
and practiced esophageal voice produces intelligible speech of
surprisingly good quality. The method is best learned from a qualified
speech therapist and often the patient will work is group sessions with
others who are learning as well as with those who have already mastered
this technique.
Although esophageal speech produces the
best quality of voice and is the most convenient monlaryngeal speech
method, there are mechanical devices available for those patients who
are unable to learn it. Artificial larynxes, both mechanical and
electric, and a device which attaches to the upper dental plate are
among these aids which may produce an intelligible voice.
So generally successful are the means
of rehabilitation that the great majority of patients who have undergone
larynectomy are able to return to full employment activity and lead
relatively normal lives.
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Patient Education
