Throat cancer

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Throat cancer is the layman's way of generally referring to the many kinds of head and neck cancers. In reviewing some of the literature available concerning throat cancer it soon becomes clear that different researchers and practitioners define the area of the throat in different ways. Some define throat cancer as the cancer of the pharynx and so refer to it as pharyngeal cancer which includes the nasopharynx, the area behind the throat (hollow tube at top of throat and behind nose extending down into the neck where it becomes the esophagus (tube leading to the stomach); the oropharynx, area at the base of the tongue, including the soft palate, and tonsils; the hypopharynx, which is the bottom of the throat. Others restrict their definition of throat cancer to include the vocal cords and larynx (voice box). However you define it, most of the cancers in these areas are squamous cell carcinomas. That means that the tumor begins to develop in the tissue lining the hollow organs of the body. These cells tend to rapidly multiply, killing the healthy cells, and, unless they are stopped or slowed down in time, death is imminent. And, regardless of what part of the throat or area surrounding the throat contains the cancer, the effects of this disease on the body systems can be widespread, dangerous, and potentially fatal.

An overview of the symptoms, risk factors, types of throat cancers, treatment of throat cancer, and statistics will be presented followed by the effects of throat cancer on the body system to help better understand what this disease entails and the possible consequences on the systems of the body afflicted with this disease. The conclusion consists of a section focusing on prevention - looking at possible ways of keeping the body’s systems out of harm’s way from this disease.

Possible symptoms

Throat cancer usually begins with symptoms that seem harmless enough, like an enlarged lymph node on the outside of the neck, a sore throat or a hoarse sounding voice. However, in the case of throat cancer, these conditions may persist and become chronic. There may be a lump or a sore in the throat or neck that does not heal or go away. There may be difficult or painful swallowing. Speaking may become difficult. There may be a persistent earache. Other possible but less common symptoms include some numbness or paralysis of the face muscles.

Risk factors

There are a wide variety of factors which can put someone at a heightened risk for throat cancer. Such factors include smoking, chewing tobacco (betal, gutkha or pan as well) heavy alcohol consumption, poor diet resulting in vitamin deficiencies (worse if this is caused by heavy alcohol intake), weakened immune system, asbestos exposure, prolonged exposure to wood dust or paint fumes, exposure to petroleum industry chemicals, and being over the age of 55 years. Finally, the presence of acid reflux disease (GERD - gastroesphogeal reflux disease) or larynx reflux disease. In the case of acid reflux disease, stomach acids flow up into the esophagus and damage its lining making it more prone to throat cancer. Ethnicity may also play a part, with African-American men in the US being found to be at a 50% higher risk of throat cancer than Caucasian men. Another risk factor includes the appearance of white patches or spots in the mouth. This is called leukoplakia and is a risk factor because in about ⅓ of the cases it develops into cancer.

Types of throat cancer

Throat cancers are classified according to their histology or cell structure, and are commonly referred to by their location in the oral cavity and neck. This is because where the cancer appears in the throat affects the prognosis - some throat cancers are more aggressive than others depending upon their location. The stage at which the cancer is diagnosed is also a critical factor in the prognosis of throat cancer.

Squamous Cell Carcinoma

Squamous cells are the epithelium (tissue layer) that is the surface cells of much of the body. Skin and mucous membranes are squamous cells. This is the most common form of larynx cancer, accounting for over 90% of throat cancer.^{[reference please]} Squamous Cell Carcinoma is most likely to appear in males over 40 years of age with a history of heavy alcohol use coupled with smoking.

Epidimoid Cancer

(See Squamous Cell Carcinoma)

Adenocarcinoma

Adenocarcinoma is a cancer of the columnar epithelium typical of the lower esophagus. It is typical of Barrett's Esophagus but may be at another location. Adenocarcinoma is thought of as a product of Barrett's Esophagus.

Examples of locational nomenclature are:

Pharangeal cancer

Hypo-Pharangeal cancer

Oro-Pharangeal cancer

Esophogeal cancer

Barrett's Esophagus is a cancer of the columnar epithelium of the lower esophagus.

Cancer of the Larynx

Cancerous tumors can occur anywhere in the larynx, like on the vocal cords (most common) or above them or below the glottis which is the opening at the top of the larynx. Less prevalent are tumors above (supraglottic) or below the glottis (subglottic) but these are also the throat cancers with the worst prognosis because they tend to spread or metastasize more rapidly than other types of throat cancer.

Treatment

Many different treatments and therapies are used in the treatment of throat cancer. The type of treatment and therapies used are largely determined by the location of the cancer in the throat area and also the extent to which the cancer has spread at time of diagnosis. Patients’ also have the right to decide whether or not they wish to consent to a particular treatment. For example, some may decide to not undergo radiation therapy which has serious side effects if it means they will be extending their lives by only a few months or so. Others may feel that the extra time is worth it and wish to pursue the treatments.

Surgery

Surgery as a treatment is sometimes used in cases of throat cancer. In such cases an attempt is made to remove the cancerous cells. This can be particularly tricky if the cancer is near the larynx and can result in the patient being unable to speak. Surgery is more commonly used to resection (remove) some of the lymph nodes to prevent further spread of the disease.

Radiation therapy

Radiation therapy is the most common form of treatment. There are different forms of radiation therapy. One of newer treatments is Intensity-modulated radiotherapy or IMRT which is able to focus more precisely so that fewer healthy cells are destroyed than was the case with some of the older radiation therapies. IMRT reduces incidental damage to the many important structures of the throat and mouth that may not be involved. However if the cancer has metastisized or is widespread, the older form of treatment may be the most effective at slowing the progression of the disease. Radiation will generally cause the patient to feel sicker and weaker for several weeks following the treatment, but is a very effective treatment in stopping the disease.

A typical radiation course could be 37 consecutive daily sessions of 11 one-minute exposures at positions encircling the neck. The patient is immobilized by a plastic mask that snaps into holes on the treatment table. The table is adjusted so that lasers mounted on the ceiling hit dots on the mask. The computer then adjusts the gantry arm and head, table, and shutters, makes the exposure and adjusts again for the next exposure.

Chemotherapy

Chemotherapy in throat cancer is not generally used to cure the cancer as such. Instead, it is used to provide an inhospitable environment for metastases so that they will not establish in other parts of the body. Typical chemotherapy agents are a combination of Taxol and Carboplatin. Erbitux is also used in the treatment of throat cancer. While not specifically a chemotherapy, Amifostine is often administered intravenously by a chemotherapy clinic prior to a patient's radiotherapy sessions. Amifostine protects the patient's gums and salivary glands from the effects of radiation.

Effects on body systems

Throat cancer has numerous negative effects on the body systems. As it can impair a person’s ability to swallow and eat, it affects the digestive system. The digestive systems job is to break down the food we consume so that the pieces are small enough to be absorbed and transported throughout the body so that the body’s cells receive the nutrients they need to function and survive. During digestion the food is chewed up and the tongue pushes it toward the back of the throat. Once here the epiglottis (flap of skin) moves across the windpipe allowing the food to be funnelled down into the esophagus. From here the food is moved along toward the stomach by a wave-like motion called peristalsis. In the case of throat cancer, the difficulty in swallowing can lead to a person to choke on their food in the early stages of digestion and interfere with the food’s smooth travels down into the esophagus and beyond. This could result in the person choking to death. A person having digestive system problems may eat less, eventually depriving all the body systems of the important nutrients needed for proper functioning. The treatments for throat cancer can also be harmful to the digestive system as well as other body systems. Radiation therapy can make a patient throw up, which can deprive a body of vital fluids (although these may be obtained through intravenous fluids if necessary). Frequent throwing up can lead to an electrolyte imbalance which has serious consequences for the proper functioning of the heart. Frequent vomiting can also upset the balance of stomach acids which has a negative impact on the digestive system, especially the lining of the stomach and esophagus.

Throat cancer can also have deleterious effects on the respiratory system. This system supplies the bodies blood cells with oxygen from the outside air that we breath. To do this it first extracts the carbon dioxide out of the outside air. In the cases of some throat cancers the air passages in the mouth and behind the nose may become blocked from lumps or the swelling from the open sores. As well, if the throat cancer is near the bottom of the throat it has a high likelihood of spreading to the lungs and interfering with the person’s ability to take in and expel oxygen. This is even more likely if the patient is a smoker because they are highly susceptible to lung cancer. If the respiratory system is unable to access enough outside air to supply the red blood cells which are specialized to transport the oxygen to all the cells in the body, the oxygen deprivation will cause the cells to wither and die. As a result, the human body will become weaker and sicker and eventually die if the disease is not caught in time.

Because throat cancer can metastasize or spread to other systems through-out the body, including bones, it can also affect the skeletal system. This is very serious because the majority of the bones found in the skeletal system contain marrow. Marrow is a special type of connective tissue which is make out of highly specialized cells which produce the body’s red blood cells. If the body is unable to replenish its red blood cells and have an ample supply available, there will not be enough of them to perform their job of carrying oxygen to all the cells in the body. Also, if the white blood cells, which are specialized to help the body fight infection, sense that something is going on with the red blood cells they may reproduce at a greater number and end up fighting a losing battle. That is why in television shows they often describe a cancer patient’s condition in terms of high or low white and red blood cell counts. So the future looks very grim for a patient once the cancer spreads to their skeletal system.

Throat cancer can also have a major impact on the circulatory system which transports nutrients absorbed by the digestive system and oxygen absorbed by the respiratory system to every cell in the body. It also helps move the waste from cells to the excretory system for elimination from the body. The circulatory system also helps the body to fight against disease. If there is little food being digested as a result of the throat cancer the circulatory system will have limited nutrients to deliver to the cells in the body. And, as mentioned above, if there is restricted oxygen intake or a shortage of red blood cells to carry it, the circulatory will be unable to perform its function of transporting the oxygen to the cells. Once again, deprived of enough nutrients and oxygen the body’s cells wither and die.

Throat cancer can also throw the nervous system into a state of chaos. This system is responsible for controlling and coordinating all the organs and organ systems. It is like the computer for the body which detects stimuli which the body and its cells are exposed to, processes this information, and then determines how each of the systems are to respond to the various stimuli. With throat cancer potentially interfering and impairing so many body systems, the nervous system can be at a loss for how guide the individual systems. It may function more like a computer with a virus with unpredictable and potentially devastating results for the patient.

With its ability to impair so many body systems, throat cancer is a disease to be taken very seriously and deserving of much more research.

Prevention/prophylaxis

In considering the previously listed risk factors and symptoms it makes sense that you should contact your doctor if you have a sore throat, difficulty in swallowing, or an earache that just does not seem to go away. This is also the case if your voice seems to be hoarse for a prolonged time. Family doctors have guidelines to follow from The Department of Health which indicate that a doctor should make an urgent appointment with a specialist in Ear Nose and Throat (ENT) if a patient presents with difficulty in swallowing or a lump in the neck area for over three weeks or a hoarse voice which has lasted over six weeks. These symptoms may not be the result of throat cancer but just to be on the safe side they should be examined.

Not smoking and not chewing tobacco (betel, gutka or pan included) will decrease your chances of developing this disease. Other preventive measures include eating a sensible, well-balanced diet. Such a diet can include alcohol, but only in moderation. If you suspect you might have acid reflux disease, it is best to contact your doctor. This is also good advice to follow if you have white spots in your mouth or have developed sore which do not seem to go away. Regular visits to a dentist are also recommended because part of the dental exam includes looking at the interior of your mouth so the dentist may notice spots or sores that a patient may have been unaware of before the exam. In this case the dentist can advise a patient to check it out further by contacting their family doctor. Early detection and treatment of this disease is crucial in a patient’s fight against this disease.

Many people may still be alive today had they taken such preventative measures. These also include some famous individuals who succumbed to this devastating disease. For example, Graham Chapman of Monty Python fame died relatively young of throat cancer. In most of his skits he is shown smoking and this was most likely what put him at heightened risk for the disease. He mentioned that the primary site of his cancer was the spot where the jet of smoke from his pipe hit the back of his throat. Likewise, Sammy Davis Junior, a heavy smoker, also died of throat cancer. The world of entertainment seems to put its stars at increased risk because smoking, heavy alcohol consumption, and poor diets are commonly found in this environment. Dr. Seuss, also a smoker, died of related jaw cancer.

Statistics for throat cancer

• In the U.S. there were 28,900 people diagnosed with cancers of the throat and oral cavity in 2002. Cancer Facts and Figures, http://www.cancer.org/downloads/STT/CancerFacts&Figures2002TM.pdf,, American Cancer Society 2002.
• Seventy-four hundred Americans are projected to die of these cancers. 1
• More than 70% of throat cancers are at an advanced stage when discovered. Throat Cancer patient information web page, http://cancer.nchmd.org/treatment.aspx?id=741, NCH Healthcare Systems, 1999
• Men are 89% more likely than women to be diagnosed with, and are almost twice as likely to die of, these cancers. 1
• African-American men are at a 50% higher risk of throat cancer than Caucasian males.^{[reference please]}
• Smoking and tobacco use are directly related to Oro-pharangeal (throat) cancer deaths. Reducing the Health Consequences of Smoking: 25 Years of Progress. A Report of the Surgeon General, U. S. Department of Health and Human Services, Public Health Service,Centers for Disease Control and Prevention, 1989.

References

 

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