What is Oral Cancer?

The Tongue (Seen from the top)

Cancer of any component of the oral cavity mentioned above is classified as oral cancer. When oral cancer spreads, it usually travels through the lymphatic system. Cancers that spread through the lymphatic system are carried along by lymph, which is a colorless watery fluid containing cells that help the body fight infection and disease. Lymphatic channels pass through various stations called lymph nodes, which are small bean-shaped organs located in groups in various parts of the body, such as in the neck, the armpits, the groin and inside the abdomen, and the central part of the chest. Cancers which originate in the oral cavity and lodge themselves distantly in other organs are still known as metastatic oral cancers.

What is the cause of Oral Cancer and how can Oral Cancer be prevented?

There are several factors, which have strong links with the production of oral cancers. The first and most important factor is tobacco abuse. Cigars, pipes, cigarettes, or chewing tobacco, dipping snuff, or using betel leaf with betel nut account for 80% to 90% of oral cancers. Because these habits are extremely prevalent in our country, nearly 33% of cancers in the Indian subcontinent are head and neck cancers, especially, oral cancers. Studies have shown that smokeless tobacco users such as gutkha users, betel nut and betel leaf users, and tobacco chewers are at particular risk of developing oral cancer. For long-time users, the risk is extremely great, making the use of snuff or chewing tobacco amongst young people a very special concern. People who stop using tobacco, even after many years of abuse, definitely benefit and greatly reduce the risk of developing oral cancers. Chronic and a heavy use of alcohol also increases the risk of oral cancer, which is extremely potentiated if the person also happens to be a smoker. Those patients who have a history of leukoplakia, which is a whitish patch inside the mouth, have an extreme predilection for developing oral cancers. The causes of leukoplakia are not well understood, but it is commonly associated with the heavy use of tobacco and alcohol. The condition usually arises in the maximally irritated areas of the oral cavity, including the gums and the mouth lining of smokeless tobacco users, and the lower lip of cigarette and pipe smokers. Another precancerous condition is called erythroplakia, which appears as a red patch in the mouth. Erythroplakia occurs most often in elderly people after 60 to 70 years of age. Melanoplakia and leukoedema are two other conditions, which are precancerously found in the oral cavity. Early diagnosis and treatment of leukoplakia and erythroplakia are important because cancer may develop in these patches. Other chronic irritant factors like sharp teeth can also cause an infection and inflammation in certain areas of the tongue, which, if longstanding, can become cancerous. It is mandatory that one stops smoking, using alcohol and smokeless tobacco, and visits the dentist regularly to have dental hygiene checked, and also to look for precancerous lesions while they are still very early.

Cancers of the Oropharynx

How does Oral Cancer present?

Cancers of the Mandible and floor of mouth.	The usual ways in which oral cancers present are as follows:
	»	A lump on the lip, or in the mouth, or in the throat.
	»	A sore on the lip, or in the mouth, or on the tongue, that does not heal.
	»	A white or red patch or black spots on the gums, tongue, or lining of the mouth.
	»	Unusual bleeding, pain, or numbness in the mouth.
	»	A sore throat that does not go away or a feeling that something is 'caught in the throat'.
	»	Difficulty or pain while chewing or swallowing.
	»	Swelling of the jaw that causes dentures to fit poorly or fall off or become uncomfortable.
	»	A change in the voice or pain in the ear.
	These symptoms can also be caused by other less serious problems. It is important that a dentist or an ENT surgeon be shown as early as possible.

How is Oral Cancer detected?
If such symptoms exist in a person, and an obvious lesion is visualized by the doctor, the most important specific investigation which is done for the patient is a biopsy, in which a small piece of the offending area is taken out and is sent for histopathological diagnosis, in which the pathologist visualizes the tissue section under the microscope and tells you conclusively whether it is a cancer or not. Depending upon the area involved, the patient will get the subsequent treatment.

How is Oral Cancer treated?
A lot depends on the patient's constitution, the grade of his disease, and its staging. Patients are usually treated by a team of specialists, which utilizes a multipronged approach. This includes an otorhinolaryngologist (ENT surgeon), a surgical oncologist, a reconstructive or plastic surgeon and a radiotherapist. The plan of treatment is tailored to fit a patient's requirements. If necessary, chemotherapy may become an add-on.

Treatment strategies.

The bastion of oral cancer treatment is surgery. If the tumor is resectable, then surgery is performed, which is an en -`bloc resection of the tumor, with a healthy margin of normal tissue, along with the draining lymph nodes in the neck. This surgery is known as a composite resection or a commando operation.

After the composite resection, the reconstructive surgeon comes into play and uses either a primary form of closure where the edges of the defect are sutured end-to-end and side-to-side, or if the defect is too large, then the reconstructive surgeon may introduce soft tissues and skin from neighboring areas in order to make the defect look less mutilating. These are known as myocutaneous flaps.

The alternative local therapy to surgery is radiation therapy. This involves the use of high energy, penetrative rays to destroy cancer cells. It also affects cancer cells only in the zone treated. Radiation therapy is also employed for palliation, that is, control of symptoms alone in an advanced endometrial cancer.

Radiation therapy can also be used in adjunct to surgery or chemotherapy, either before or after.

Teletherapy or external radiation is given via a machine remote from the body, while brachytherapy or internal radiation is given by implanting a radioactive source within the uterine cavity. Patient may or may not require both modalities of radiation.

Radiation therapy, after initial planning, usually takes just 5 to 10 minutes per day, 5 days a week for about 6 weeks. This time period is flexible depending upon the modality of radiation used.

However, if the patient is being subjected to internal radiation or brachytherapy, then the patient needs to be hospitalized for that short period of time while the source is in place. It is also mandatory that while the radioactive source is in place, the patient receives no relatives, because there is a very small chance of the radioactive source leaking radiation to affect the relatives.

Besides local therapy, the best attempt to control cancer cells circulating in the body and lodged at places other than the uterine cavity is by using systemic therapy (therapy which affects the entire systems of the body), which is in the form of injections or oral drugs. This form of treatment is called chemotherapy.

This treatment is given in a cyclical manner (each set of drugs is repeated usually after every 3 to 4 weeks). Chemotherapy can also be used in combination with surgery, radiotherapy, or both, either before or after.

What are the side effects of treatment for Oral Cancer?
Unfortunately, the various modalities, which are employed for treating oral cancer, are not without their side effects. The severity and the quality of these side effects depends largely upon the type of modality of treatment employed, and also the general condition of the patient during and before the treatment. Doctors and nurses play a very important role in explaining to the patient the side effects and the symptoms associated with the same during therapy.

It is important that the patient and his relatives ask the doctor about the side effects of treatment, before the treatment is constituted.

Surgery to remove a small tumor in the mouth usually does not cause any long lasting problems.

For a larger tumor, as the surgeon has to remove part of the palate or the tongue or the jaw, the surgery is definitely going to affect the patient's ability to chew, swallow, talk, and also the patient is going to look different cosmetically.

Postoperatively, the patient's face will be swollen, but the swelling is only temporary and will disappear within a few weeks. However, because removing all the lymph node stations can slow the flow of lymph, there may be a swelling which lasts for a longer period of time if the drainage to other lymph node stations, which are more remote, is not established adequately.

Before starting radiation, the patient should see a dentist in order to check out his or her dental hygiene. Radiation therapy makes the mouth sore and also causes difficulty in swallowing saliva and makes it difficult for the patient to masticate . The commonest symptom is extreme fatigue, and, therefore, often patients are requested to rest.
One of the common symptoms, which are seen after radiotherapy, is dry, reddened skin, and loss of appendages of the skin such as hair, from the area radiated.
There is also a decrease in the white blood cell count that has got an immunoprotective effect against infections.

The various drugs used in chemotherapy cause a varied spectrum of side effects. The severity and variability of these symptoms are very individualistic, changing from patient to patient.

Some of the common side effects are:

»	Infections.
»	Skin rashes.
»	Loss of hair.
»	Diarrhea.
»	Vomiting.
»	Tingling and numbness in the fingers and toes.
»	Hearing loss.

Most are temporary and recede after therapy is over. Hair growth gradually starts after cessation of chemotherapy.

The medical oncologist (chemotherapist) will usually be able to reduce the severity and spectrum of these side effects.

The psychology of the patient is very important during therapy. The better psychologically prepared the patient is, the better are his or her chances of having decreased side effects.

The patient should drink large quantities of liquids while therapy is in progress, and preferably avoid uncooked or raw food. Water for drinking should be filtered or boiled. Any relative or person who has any infection such as common cold should be asked to desist from coming close to the patient.

How do Oral Cancer patients get back to normal life after treatment?
Especially in those patients who undergo a composite resection and their facial features are changed for the worse, it is vitally important that the doctor, nurses and relatives get together to make the patient feel as much at home as possible.

During rehabilitation, it is important for both clinicians and relatives to realise that physical recovery always outpaces emotional recovery and just the removal of the final stitch does not signify the end of the recovery phase. A significant part of the recovery process for the relatives is to be as positive as possible and to get the patient off his or her emotional crutches as early as possible.

Rehabilitation is an extremely important segment of treatment for patients with oral cancers. The goals of rehabilitation basically not only depend on the extent of the disease but also the treatment, which has been offered to the patient, which is unfortunately often quite mutilating. It is a very important role that the reconstructive surgeon has to play, because it is he who will be able to decide as to how the patient is finally going to look after the surgery is over. In other words, the patient's entire social outlook is wholly dependent on how less mutilating the ultimate result is, at the same time not compromising from the adequate safety margins required for clearance of cancer.