The most frequently occurring cancers of the head and neck area are oral cancers and laryngeal cancers. Almost half of all the head and neck cancers occur in the oral cavity, and a third are found in the larynx. By definition, the term "head and neck cancers" usually excludes tumors that occur in the brain.
Head and neck cancers involve the respiratory tract and the digestive tract, and they interfere with the functions of eating and breathing. Laryngeal cancers affect speech. Loss of any of these functions is significant. Hence, early detection and appropriate treatment of head and neck cancers is of utmost importance.
Roughly 10% of all cancers are related to the head and the neck. For cancer of the pharynx and oral cavity, there was an estimated 30,200 new cases in 2000. Incidence rates are highest in women and men over age 40, and more than twice as high in men as in women. The rates of oral cancers and deaths due to this cancer have been declining.
Among the major cancers, the survival rate for head and neck cancers is one of the poorest. Less than 50% of the patients survive five years or more after initial diagnosis. This is because the early signs of head and neck cancers are frequently ignored. Hence, when they are first diagnosed, these types of cancers are often in an advanced stage and not very amenable to treatment.
The risk for both oral cancer and laryngeal cancer seems to increase with age. Most of the cases occur in individuals over 40 years of age, the average age at diagnosis being 60. While oral cancer strikes men twice as often as it does women, laryngeal cancer is four times more common in men than in women. Both diseases are more common in African Americans than among Caucasians.
Although the exact cause for these cancers is unknown, tobacco is regarded as the single greatest risk factor: 75–80% of the oral and laryngeal cancer cases occur among smokers. Heavy alcohol use has also been included as a risk factor. A combination of tobacco and alcohol use increases the risk for oral cancer by six to 15 times more than for users of either substance alone. In rare cases, irritation to the lining of the mouth, due to jagged teeth or ill-fitting dentures, has been known to cause oral cancer. Exposure to asbestos also appears to increase the risk of developing laryngeal cancer.
In the case of lip cancer, just like skin cancer, exposure to sun over a prolonged period has been shown to increase the risk. In the Southeast Asian countries (India and Sri Lanka), chewing of betel nut has been associated with cancer of the lining of the cheek. An increased incidence of nasal cavity cancer has been observed among furniture workers, probably due to the inhalation of wood dust. A virus (Epstein-Barr) has also been shown to cause nasopharyngeal cancer.
Head and neck cancers are one of the easiest to detect. The early signs can be both seen and felt. The signs and symptoms depend on the location of the cancer:
When detected early and treated appropriately, head and neck cancers have an excellent chance of being cured completely.
Specific diagnostic tests used depend on the location of the cancer. The standard tests are:
The first step in diagnosis is a complete and thorough examination of the oral and nasal cavity, using mirrors and other visual aids. The tongue and the back of the throat are examined as well. Any suspicious looking lumps or lesions are examined with fingers (palpation). In order to look inside the larynx, the doctor may sometimes perform a procedure known as laryngoscopy. In indirect laryngoscopy, the doctor looks down the throat with a small, long handled mirror. Sometimes the doctor inserts a lighted tube (laryngoscope or a fiberoptic scope)
X rays of the mouth, the sinuses, the skull, and the chest region may be required. A computed tomography scan (CT scan), a procedure in which a computer takes a series of x ray pictures of areas inside the body, may be done. Ultrasonograms (images generated using sound waves) or an MRI (magnetic resonance imaging) a procedure in which a picture is created using magnets linked to a computer), are alternate procedures which a doctor may have done to get detailed pictures of the areas inside the body.
When a sore does not heal or a suspicious patch or lump is seen in the mouth, larynx, nasopharynx, or throat, a biopsy may be performed to rule out the possibility of cancer. The biopsy is the most definitive diagnostic tool for detecting the cancer. If cancerous cells are detected in the biopsied sample, the doctor may perform more extensive tests in order to find whether, and to where, the cancer may have spread.
The cancers can be treated successfully if diagnosed early. The choice of treatment depends on the size of the tumor, its location, and whether it has spread to other parts of the body.
In the case of lip and mouth cancers, sometimes surgery is performed to remove the cancer. Radiation therapy, which destroys the cancerous cells, is also one of the primary modes of treatment, and may be used alone or in combination with surgery. If lip surgery is drastic, rehabilitation cosmetic or reconstructive surgery may have to be considered. Some cancers of the lip may be removed by Mohs' surgery, also known micrographic surgery. Using this method, the surgeon removes the tumor in thin slices, examining them immediately under the microscope to look for cancer cells. More slices are taken until the cancer is completely removed. The amount of normal tissue removed is minimized using this method.
Cancers of the nasal cavity are often diagnosed late because they have no specific symptoms in their early stages, or the symptoms may just resemble chronic sinusitis. Hence, treatment is often complex, involving a combination of radiotherapy and surgery. Surgery is generally recommended for small tumors. If the cancer cannot be removed by surgery, then radiotherapy is used alone.
Treatment of oropharynx cancers (cancers that are either in the back of the tongue, the throat, or the tonsils) generally involves radiation therapy and/or surgery. After aggressive surgery and radiation, rehabilitation is often necessary and is an essential part of the treatment. The patient may experience difficulties with swallowing, chewing, and speech and may require a team of health care workers, including speech therapists, prosthodontists, occupational therapists, etc.
Cancers of the nasopharynx are different from the other head and neck cancers in that there does not appear to be any association between alcohol and tobacco use and the development of the cancer. In addition, the incidence is seen primarily in two age groups: young adults and 50–70 year-olds. The Epstein-Barr virus has been implicated as the causative agent in most patients. While 80–90% of small tumors are curable by radiation therapy, advanced tumors that have spread to the bone and cranial nerves are difficult to control. Surgery is not very helpful and, hence, is rarely attempted. Radiation remains the only treatment of choice to treat the cancer that has metastasized (traveled) to the lymph nodes in the neck.
In the case of cancer of the larynx, radiotherapy is the first choice to treat small lesions. This is done in an attempt to preserve the voice. If the cancer recurs later, surgery may be attempted. If the cancer is limited to one of the two vocal cords, laser excision surgery is used. In order to treat advanced cancers, a combination of surgery and radiation therapy is often used. Because the chances of a cure in the case of advanced laryngeal cancers are rather low with current therapies, the patient may be advised to participate in clinical trials so they may get access to new experimental drugs and procedures, such as chemotherapy, that are being evaluated.
When only part of the larynx is removed, a relatively slight change in the voice may occur—the patient may sound slightly hoarse. However, in a total laryngectomy, the entire voice box is removed. The patients then have to re-learn to speak using different approaches, such as esophageal speech, tracheo-esophageal (TE) speech, or by means of an artificial larynx.
In esophageal speech, the patients are taught how to create a new type of voice by forcing air through the esophagus (food pipe) into the mouth. This method has a high success rate of approximately 65% and patients are even able to go back to jobs that require a high level of verbal communication, such as telephone operators and salespersons.
In the second approach, TE speech, a small opening called a fistula, is created surgically between the trachea (breathing tube to the lungs) and the esophagus (tube into the stomach) to carry air into the throat. A small tube, known as the "voice prosthesis," is placed in the opening of the fistula to keep it open and to prevent food and liquid from going down into the trachea. In order to talk, the stoma (or the opening made at the base of the neck) must be covered with one's thumb during exhalation. As the air is forced out from the trachea into the esophagus, it vibrates the walls of the esophagus. This produces a sound that is then modified by the lips and tongue to produce normal sounding speech.
In the third approach, an artificial larynx, a battery driven vibrator, is placed on the outside of the throat. Sound is created as air passes through the stoma (opening made at the base of the neck) and the mouth forms words.
Recent developments have been made with the use of lasers for treating many types of cancer. Laser therapy destroys cancer cells by the use of high-intensity light. It is often used to relieve symptoms of cancer such as bleeding or obstruction, particularly when other treatments are ineffective. Laser surgery can also treat cancer by shrinking or destroying tumors. Laser surgery is a standard treatment for certain stages of glottis. Although there are several different kinds of lasers, only the Carbon dioxide (CO2) laser, Neodymium:yttrium–aluminum–garnet (Nd:YAG) laser, and argon laser are widely used in medicine. The CO2 and Nd:YAG lasers are used to shrink or destroy tumors. Laser surgery is also used to help relieve symptoms caused by cancer (palliative care) in addition to its use in destroying cancer cells.
Since cancer cannot grow or spread without forming new blood vessels, research is being conducted to find ways to stop angiogenesis. Scientists are exploring the use of natural and synthetic angiogenesis inhibitors, also called anti-angiogenesis agents, in anticipation that these chemicals will prevent tumor spread by inhibiting new blood vessel formation.
Taxanes are a group of cancer drugs that includes paclitaxel (Taxol) and docetaxel (Taxotere). Taxanes inhibit cancer cell growth by arresting cell division. They are also known as antimitotic or antimicrotubule agents or mitotic inhibitors.
Photodynamic therapy (also called PDT, photoradiation therapy, phototherapy, or photochemotherapy) is a treatment for some types of cancer including larynx and oral cavity.
Important research is being conducted investigating new treatments for several head and neck cancers. There are many new promising treatments and improvements to current therapies such as:
Comorbidities (other illnesses) that may be present are an important determinant of overall survival in people with head and neck cancer.
With early detection and immediate treatment, survival rates can be dramatically improved. For lip and oral cancer, if detected at its early stages, almost 80% of the patients survive five years or more. However, when diagnosed at the advanced stages, the five year survival rate drops to a mere 18%.
Cancers of the nasal cavity often go undetected until they reach an advanced stage. If diagnosed at the early stages, the five-year survival rates are 60–70%. However,
if cancers are more advanced, only 10–30% of the patients survive five years or more.
In cancer of the oropharynx, 60–80% of the patients survive five years or more if the cancer is detected in the early stages. As the cancer advances, the survival rate drops to 15–30%.
Patients who are diagnosed with early stage cancers that have originated in the nasopharynx have an excellent chance of a complete cure (almost 95%). Unfortunately, most of the time the patients are in an advanced stage at the time of initial diagnosis. With the new chemotherapy drugs, the five year survival rate has improved and 5–40% of the patients survive five years or longer.
Small cancers of the larynx have an excellent five-year survival rate of 75–95%. However, as with most of the head and neck cancers, the survival rates drop dramatically as the cancer advances. Only 15–25% of the patients survive five years or more after being initially diagnosed with advanced laryngeal cancer.
Advances in detecting head and neck cancer at an early stage are being made. Patients' prognoses will improve as technological advances are made. Some of the research that is being conducted includes DNA mutations (changes) that occur in genes. Damage to certain DNA can lead to increased growth of abnormal cells and
Using targeted chemoradiation, one clinical study revealed that statistical projections for overall and cancer-related five-year survival was 38.8% and 53.6%, respectively for patients with advanced (stage III-IV) carcinoma of the head and neck.
Depending on the diagnosis, disease stage, level of nursing care required, and different psychosocial factors, the patient's health care needs will vary. The care required is unique to each patient and family. For patients who will be in transitional care, an optimal integration between inpatient and outpatient care is needed to ensure the best care possible. Outpatient care includes home care, rehabilitation centers, nursing homes, and hospice care. Health care teams should make the transition from the different types of inpatient and outpatient care as easy as possible. Effective communication between professionals is critical.
A dental team with experience in oral oncology, may reduce the risk of oral complications for patients with oral cancers.
Refraining from the use of all tobacco products (cigarettes, cigars, pipe tobacco, chewing tobacco), consuming alcohol in moderation, and practicing good oral hygiene are some of the measures that one can take to prevent head and neck cancers. Since there is an association between excessive exposure to the sun and lip cancer, people who spend a lot of time outdoors in the sun should protect themselves from the sun's harmful rays. Regular physical examinations, or mouth examination by the patient himself, or by the patient's doctor or dentist, can help detect oral cancer in its very early stages.
Since working with asbestos has been shown to increase one's risk of getting cancer of the larynx, asbestos workers should follow safety rules to avoid inhaling asbestos fibers. Also, malnutrition and vitamin deficiencies have been shown to have some association with an increased incidence of head and neck cancers. The American Cancer Society recommends eating a healthy diet, consisting of at least five servings of fruits and vegetables every day, and six servings of food from other plant sources such as cereals, breads, grain products, rice, pasta, and beans. Reducing one's intake of high-fat food from animal sources is advised. Following the The Dietary Guidelines for Americans published by the United States Department of Agriculture and Health and Human Services can provide a broad overall view of good nutrition.
These dietary guidelines include these seven basic recommendations:
The Food Guide Pyramid was created by the United States Department of Agriculture to help Americans choose foods from each food grouping. The food pyramid, developed by nutritionists, provides a visual guide to healthy eating.
Angiogenesis—The formation of blood vessels around a tumor.
Biopsy—The surgical removal and microscopic examination of living tissue for diagnostic purposes.
Chemotherapy—Treatment of cancer with synthetic drugs that destroy the tumor either by inhibiting the growth of the cancerous cells or by killing the cancer cells.
Clinical trials—Highly regulated and carefully controlled patient studies, where either new drugs to treat cancer or novel methods of treatment are investigated.
Computerized tomography scan (CT scan)—A medical procedure where a series of x rays are taken and put together by a computer in order to form detailed pictures of areas inside the body.
Growth factors—Growth factors or human growth factors are compounds made by the body that function to regulate cell division and cell survival. Some growth factors are also produced in the laboratory by genetic engineering and are used in biological therapy. Growth factors are significant because they can induce angiogenesis, the formation of blood vessels around a tumor. These growth factors also encourage cell proliferation, differentiation, and migration on the surfaces of the endothelial cells.
Laryngoscopy—A medical procedure that uses flexible, lighted, narrow tubes inserted through the mouth or nose to examine the larynx and other areas deep inside the neck.
Magnetic resonance imaging (MRI)—A medical procedure used for diagnostic purposes where pictures of areas inside the body can be created using a magnet linked to a computer.
p53 gene—A tumor suppressor gene that typically inhibits the tumor growth. This gene is often altered in many types of cancer.
Radiation therapy—Treatment using high energy radiation from x-ray machines, cobalt, radium, or other sources.
Stoma—When the entire larynx must be surgically removed, an opening is surgically created in the neck so that the windpipe can be brought out to the neck. This opening is called the stoma
Taxanes—Anticancer drugs that inhibit cancer cell growth by arresting cell division. Also known as antimitotic or antimicrotubule agents or mitotic inhibitors.
Ultrasonogram—A procedure where high-frequency sound waves that cannot be heard by human ears are bounced off internal organs and tissues. These sound waves produce a pattern of echoes which are then used by the computer to create sonograms, or pictures of areas inside the body.
X rays—High energy radiation used in high doses, either to diagnose or treat disease.
Harrison, Louis B., et al., eds. Head and Neck Cancer: A Multidisciplinary Approach. Philadelphia: Lippincott Williams & Wilkins Publishers, 1999.
Thawley, Stanley E., et al., eds. Comprehensive Management of Head and Neck Tumors. 2nd ed. London: W. B. Saunders Co., 1999.
American Association of Oral and Maxillofacial Surgeons. 9700 W. Bryn Mawr; Rosemont, IL 60018. (800) 467-5268. <http://www.aaoms.org>.
American Dietetic Association. 216 W. Jackson Blvd. Chicago, IL 60606-6995. (312) 899-0040. <http://www.eatright.org>.
International Association of Laryngectomees (IAL). 7440 North Shadeland Avenue, Suite 100, Indianapolis, IN46250. <http://www.larynxlink.com/welcome.html>.
National Cancer Institute (National Institutes of Health). 9000 Rockville Pike, Bethesda, MD 20892. (800) 422-6237. <http://cancernet.nci.nih.gov>.
National Oral Health Information ClearingHouse. 1 NOHIC Way, Bethesda, MD 20892-3500. (301) 402-7364. <http://www.nohic.nih.gov>.
Oral Health Education Foundation, Inc. 5865 Colonist Drive, P.O. Box 396, Fairburn, GA 30213. (770) 969-7400.
Support for People with Oral and Head and Neck Cancer (SPOHNC). P.O. BOX 53 Locust Valley, NY 11560-0053. (800) 377-0928. <http://www.spohnc.org>.
Crystal Heather Kaczkowski, MSc.