Head and Neck Cancer

Definition

The term head and neck cancers refers to a group of cancers found in the head and neck region. This includes tumors found in:

• Oral cavity (mouth): the lips, the tongue, the teeth, the gums, the lining inside the lips and cheeks, the floor of the mouth (under the tongue), the roof of the mouth, and the small area behind the wisdom teeth are all included in the oral cavity.
• Oropharynx: includes the back one-third of the tongue, the back of the throat, and the tonsils.

• Nasopharynx: includes the area behind the nose.
• Hypopharynx: the lower part of the throat.
• Larynx (voice box, located in front of the neck in the region of the Adam's apple): in the larynx, the cancer can occur in any of the three regions—the glottis (where the vocal cords are); the supraglottis (the area above the glottis), and the subglottis (the area that connects the glottis to the windpipe).

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.

Description

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.

Causes and symptoms

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:

• Mouth and oral cavity: a sore that does not heal within two weeks, unusual bleeding from the teeth or gums, a white or red patch in the mouth, or a lump or thickening in the mouth, throat, or tongue.
• Larynx: persistent hoarseness or sore throat, difficulty breathing, or pain.
• Hypopharynx and oropharynx: difficulty in swallowing or chewing food or ear pain.
• Nose, sinuses, and nasopharyngeal cavity: pain, bloody discharges from the nose, blocked nose, and frequent sinus infections that do not respond to standard antibiotics.

When detected early and treated appropriately, head and neck cancers have an excellent chance of being cured completely.

Diagnosis

Specific diagnostic tests used depend on the location of the cancer. The standard tests are:

Physical examination

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) through the patient's nose or mouth. As the tube goes down the throat, the doctor can observe areas that cannot be seen by a simple mirror. This procedure is called a direct laryngoscopy. Sometimes patients may be given a mild sedative to help them relax, and a local anesthetic to ease any discomfort.

Blood tests

The doctor may order blood or other immunological tests. These tests are aimed at detecting antibodies to the Epstein-Barr virus.

Imaging tests

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.

Biopsy

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.

Treatment

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:

• Tumor growth factors. These hormone-like substances that are naturally occurring in the body typically promote cell growth. Some tumors may grow quickly because of excessive growth factors. New drugs like C-225 may help inhibit tumor growth. C-225 targets a specific area on the cancer cells' surface; it may eventually be used to treat other cancers such as colon, prostate, bladder, ovarian, and non-small cell lung cancer.
• New chemotherapy techniques. Intraarterial chemotherapy, where drugs are injected into arteries feeding the cancer, is being tested in combination with radiation therapy in an attempt to improve their effectiveness. Another new approach uses intralesional chemotherapy (injecting the drug directly into the tumor). Preliminary results have been promising with these new chemotherapies.
• New radiotherapy methods. Studies have been underway testing the efficacy of new radiation regimens delivering twice-a-day irradiation. Higher cure rates have been demonstrated.
• Vaccines may be effective by helping the immune system to recognize and attack the cancer cells.

Prognosis

Comorbidities (other illnesses) that may be present are an important determinant of overall survival in people with head and neck cancer.

Oral cavity

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%.

Nose and sinuses

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.

Oropharynx

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%.

Nasopharynx

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.

Larynx

Small cancers of the larynx have an excellent fiveyear 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 formation of cancers. Recent studies suggest that tests to detect p53 gene alterations may allow very early detection of oral and oropharyngeal tumors. Other substances under investigation that may help early prognosis of cancers are epidermal growth factor receptor, transforming growth factoralpha, and cyclin D1.

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.

Health care team roles

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.

Prevention

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 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:

• Eat a variety of foods.
• Control your weight.
• Eat a low-fat, low-cholesterol diet.
• Eat plenty of vegetables, fruits, and grains.
• Eat sugar in moderation.
• Use salt in moderation.
• If you drink alcohol, do so in moderation; no more than two drinks per day of wine, beer, or spirits.

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.

KEY TERMS

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.

Resources

BOOKS

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.

ORGANIZATIONS

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, IN 46250. 〈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〉.

Head and Neck Cancer

Definition

The term head and neck cancers refers to a group of cancers found in the head and neck region. This includes tumors found in:

• The oral cavity (mouth). The lips, the tongue, the teeth, the gums, the lining inside the lips and cheeks, the floor of the mouth (under the tongue), the roof of the mouth and the small area behind the wisdom teeth are all included in the oral cavity.
• The oropharynx (which includes the back one-third of the tongue, the back of the throat and the tonsils).
• Nasopharynx (which includes the area behind the nose).
• Hypopharynx (lower part of the throat).
• The larynx (voice box, located in front of the neck, in the region of the Adam's apple). In the larynx, the cancer can occur in any of the three regions: the glottis (where the vocal cords are); the supraglottis (the area above the glottis); and the subglottis (the area that connects the glottis to the windpipe).

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 of the cancers are found in the larynx. By definition, the term "head and neck cancers" usually excludes tumors that occur in the brain.

Description

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. It is estimated that more than 55,000 Americans will develop cancer of the head and neck in 1998, and nearly 13,000 will die from the disease. The American Cancer Society estimates that in 1998, approximately, 11,100 new cases of laryngeal cancer alone will be diagnosed and 4,300 people will die of this disease. Oral cancer is the sixth most common cancer in the United States. Approximately 40,000 new cases are diagnosed each year and it causes at least 8,000 deaths. 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 it is first diagnosed, it is 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 black Americans than among whites.

Causes and symptoms

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 6-15 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 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 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:

• Mouth and oral cavity: a sore that does not heal within two weeks, unusual bleeding from the teeth or gums, a white or red patch in the mouth, a lump or thickening in the mouth, throat, or tongue.
• Larynx: persistent hoarseness or sore throat, difficulty breathing, or pain.
• Hypopharynx and oropharynx: difficulty in swallowing or chewing food, ear pain.
• Nose, sinuses, and nasopharyngeal cavity: pain, bloody discharges from the nose, blocked nose, and frequent sinus infections that do not respond to standard antibiotics.

When detected early and treated appropriately, head and neck cancers have an excellent chance of being cured completely.

Diagnosis

Specific diagnostic tests used depend on the location of the cancer. The standard tests are:

Physical examination

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) through the patient's nose or mouth. As the tube goes down the throat, the doctor can observe areas that cannot be seen by a simple mirror. This procedure is called a direct laryngoscopy. Sometimes patients may be given a mild sedative to help them relax, and a local anesthetic to ease any discomfort.

Blood tests

The doctor may order blood or other immunological tests. These tests are aimed at detecting antibodies to the Epstein-Barr virus, which has been known to cause cancer of the nasopharynx.

Imaging tests

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.

Biopsy

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.

Treatment

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.

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, 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.

Prognosis

Oral Cavity

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%.

Nose and sinuses

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.

Oropharynx

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%.

Nasopharynx

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.

Larynx

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.

Prevention

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.

KEY TERMS

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.

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.

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.

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.

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, therefore, 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.

Resources

ORGANIZATIONS

American Association of Oral and Maxillofacial Surgeons. 9700 West Bryn Mawr Ave., Rosemont, IL 60018-5701. (847) 678-6200. 〈http://www.aaoms.org〉.

International Association of Laryngectomees (IAL). 7440 North Shadeland Ave., Suite 100, Indianapolis, IN 46250. 〈http://www.larynxlink.com/〉.

National Cancer Institute. Building 31, Room 10A31, 31 Center Drive, MSC 2580, Bethesda, MD 20892-2580. (800) 422-6237. 〈http://www.nci.nih.gov〉.

National Oral Health Information ClearingHouse; 1 NOHIC Way, Bethesda, MD 20892-3500. (301)-402-7364.

Oral Health Education Foundation, Inc. 5865 Colonist Drive, P.O. Box 396, Fairburn, GA 30213. (770) 969-7400.

Head and neck cancers

Definition

The group of cancers found in the head and neck region, excluding tumors of the eyes and brain.

Description

The tumors associated with head and neck cancers are found in several regions, including the lips, tongue, mouth, nasal passages, pharynx, larynx (voice box), salivary glands, thyroid gland, and parathyroid glands. Many head and neck cancers interfere with the functions of eating and breathing. Laryngeal cancer affects speech. Loss of any of these functions is significant. Therefore, early detection and appropriate treatment is of utmost importance.

Roughly 5% of all cancers are related to the head and the neck. It is estimated that more than 59, 000 Americans will develop cancer of the head and neck in 2001, and 13, 000 will die from the disease.

The common cancers of the head and neck area are oral cancers , thyroid cancer , and laryngeal cancer. Half of all head and neck cancers occur in the oral cavity and pharynx, a third are thyroid cancer, and almost 20% are found in the larynx. The American Cancer Society estimates that in 2001 approximately 10, 000 new cases of laryngeal cancer will be diagnosed and 4, 000 people will die of this disease. New cases of thyroid cancer in 2001 will likely reach over 19, 000 and result in 1, 300 deaths. Oral cancer is the tenth most common cancer in the United States, reaching nearly 30, 000 new cases each year and causing at least 7, 800 deaths.

The survival rates for head and neck cancers varies from good to poor, depending on the specific cancer. About 54% of the patients diagnosed with oral cancer will survive five years or more after the initial diagnosis. Laryngeal cancer has a 5-year survival rate of nearly 65%. Among the different cancers, thyroid cancer has one of the better 5-year survival rates, approaching 95%. The poorer survival rates for some head and neck cancers result because the early signs of these cancers are frequently ignored. Hence, when first diagnosed, they are often in an advanced stage and not very amenable to treatment.

Tobacco is regarded as the single greatest risk factor contributing to the occurrence of oral and laryngeal cancer: 75% to 80% of these patients are 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 6 to 15 times more than for users of either substance alone. Exposure to asbestos appears to increase the risk of developing laryngeal cancer. The chance for developing certain types of thyroid cancer is linked to an exposure to radiation.

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, and the average age at diagnosis is 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 whites. Thyroid cancer is three times more common in women than in men and is usually diagnosed between the ages of 30 and 50.

Types of cancers

There are many types of head and neck cancers. These are classified by where the cancer is found:

• Oral cancers occur in the mouth, or oral cavity, which includes the lips, the lining inside the lips and cheeks, the front two-thirds of the tongue, the teeth, the gums, the floor of the mouth (under the tongue), the roof of the mouth, and the small area behind the wisdom teeth. Symptoms and signs include a mouth sore that does not heal within two weeks, unusual bleeding from the teeth or gums, or a lump in the gums, mouth, or tongue.
• Lip cancers occur on the inside or outside surface of the lips. Signs of this cancer include a lump on the inside of the lip or a sore on the outside, which is usually a form of skin cancer.
• Oropharyngeal cancer is found on the back one-third of the tongue, the upper section of the pharynx, and the area around the tonsils. Symptoms include a lump in the back of the mouth or throat, ear pain, or difficulty swallowing.
• Nasopharyngeal cancer is found in the area behind the nose and the upper section of the pharynx, the area just behind the mouth. Symptoms include difficulty breathing or speaking, pain or ringing in ears, frequent headaches, or trouble hearing.
• Hypopharyngeal cancer is found only in the bottom section of the pharynx. Symptoms include a sore throat that does not subside, difficulty swallowing, a lump in the neck, or ear pain.
• Laryngeal cancer starts in the larynx, which is located in front of the neck, in the region of the Adam's apple. Symptoms include pain when swallowing, a sore throat that does not subside, a change in voice, or ear pain.
• Paranasal sinus cancer and nasal cancer develop in the small, hollow spaces in the nose called the sinuses and in the nasal cavity, which is the passageway for air moving to the throat during breathing. Symptoms include frequent sinus infections, nosebleeds, a sore inside the nose that does not heal, or pain in the sinus area.

• Salivary gland tumors form in the salivary glands, which produce saliva to help prevent the mouth from drying out and aids with digestion. They are located under the jaw, in front of the ears, underneath the tongue, and in other regions of the digestive tract. Symptoms include swelling under the chin or around the jawbone, facial numbness, muscles in the face that will not move, or persistent pain in the face, chin, or neck.
• Thyroid cancer is found on the thyroid gland, which is located in the front of neck and secretes hormones that help regulate body temperature and metabolism. Symptoms include a lump on the neck, pain in the neck region, a cough with bleeding, or difficulty swallowing or breathing.
• Parathyroid cancer is found on one or on all four of the small parathyroid glands, which secrete a hormone that controls the level of calcium in the blood. They are located in neck area, with a pair on either side of the thyroid gland. Symptoms include bone pain , a lump in the neck, weak muscles, or nausea.

See Also Cigarettes; Laryngeal nerve palsy; Squamous cell carcinoma of the skin; Alcohol consumption

Resources

BOOKS

Cummings, C.W., J.M. Fredrickson, L.A. Harker, et al. Otolaryngology - Head and Neck Surgery. St. Louis: Mosby-Year Book, Inc., 1998.

Fraker, D.L., M. Skarulis, and V. Livolsi. "Thyroid Tumors." In Cancer: Principles and Practice of Oncology 5th ed. DeVita, V. Jr., et al, eds. Philadelphia: Lippincott-Raven Publishers, 1997.

PERIODICALS

Greenlee, R., M. Hill-Harmon, T. Murray, and M. Thun. "Cancer Statistics, 2001." CA: A Cancer Journal for Clinicians 51 (2001): 15-36.

OTHER

"PDQ: A Cancer Information Database." CancerNet 2 July 2001 <http://www.nci.nih.gov>

Lata Cherath, Ph.D.

Monica McGee, M.S.

KEY TERMS

Larynx

—The voice box or sound-producing organ in the body, located in the upper section of the trachea (windpipe). The movement of the muscles of this organ alters the sounds emitted by the vocal cords.

Pharynx

—The space behind the mouth that connects to the trachea and the esophagus (swallowing tube). It serves as a passageway for food and air.

Risk factor

—Anything that increases a person's chance of developing a disease.