Oral cancer

What is oral cancer?

ral cancer is cancer anywhere in the front of the mouth. It includes any cancer:

• on or inside the lining of the lips
• on the front two-thirds of the tongue or the floor of the mouth underneath the tongue
• inside the surface of the cheeks
• on the hard palate (the front of the roof of the mouth)
• on the gums
• in the area behind the wisdom teeth.

Cancers in the back of the mouth, such as on the soft palate (the back of the roof of the mouth), the back of the tongue, or the back of the throat, are not considered oral cancer.

Almost all oral cancers are a type of cancer called squamous cell carcinoma, in which surface cells grow and divide in an uncontrolled way.

Oral cancer occurs more often in men than in women and is strongly associated with smoking or chewing tobacco. About 90% of people with oral cancer use tobacco. The risk increases with the amount and length of tobacco use. Alcohol use and spending too much time in the sun also increase the risk of oral cancer.

People with oral cancer are more likely to develop cancer of the larynx (voice box), esophagus, or lung.

Symptoms of oral cancer

Symptoms of oral cancer include:

• a mouth sore that doesn't heal
• a persistent, abnormal white or red patch inside the mouth or on the lip or tongue
• a lump or thickening in your lips, mouth, or cheek that doesn't go away
• a sore throat that doesn't go away
• voice changes
• trouble chewing or swallowing
• trouble moving your jaw or tongue
• loose teeth
• numbness in your tongue or another part of your mouth
• pain around your teeth or in your jaw
• pain or irritation in the mouth that doesn't go away
• unexplained weight loss
• swelling in your jaw
• a lump or mass in your neck
• the constant feeling that something is caught in your throat.

Most often these symptoms are caused by other, less serious medical problems. But if any symptoms last for two weeks or longer, see your doctor.

Diagnosing oral cancer

Diagnosis starts with a physical exam. Whether or not you have symptoms, your doctor or dentist should look for abnormal spots in your mouth during a routine visit. Your doctor may also feel for any lumps or masses in your neck.

If your provider suspects a problem, you may need to see an oral surgeon or an ear, nose, and throat surgeon (otolaryngologist). To test for cancer, the surgeon will do a biopsy, which involves removing a small piece of tissue from the abnormal area. The tissue is then examined under a microscope.

After the diagnosis is made, your doctor will determine if the cancer has spread beyond the oral cavity with other tests. He or she needs this information to decide on the treatment. The tests often include

• an MRI scan of the head and neck
• a CT scan of the chest, to look for cancer in lymph nodes
• a PET scan, to look for cancer in other parts of the body.

Your doctor may also look at your larynx, esophagus, and lungs by sliding a tube with a tiny camera on the end of it down your throat.

Expected duration of oral cancer

The chances of recovery depend on many factors. These include:

• where the cancer is found
• how far it has spread
• your general health.

Preventing oral cancer

The biggest risk factors for oral cancer are smoking and using smokeless tobacco (chewing tobacco). Drinking alcohol is another big risk factor. If you smoke or chew tobacco and drink alcohol, your risk is even higher.

If you smoke or chew tobacco, get the help you need to stop. If you smoke or chew tobacco now or did so in the past, watch for symptoms. Ask your doctor or dentist to check your mouth at least once a year for abnormal areas, so that cancer can be found early.

Cancer of the lip is linked to too much time in the sun. If you are outside a lot, especially as part of your job, take these steps to protect yourself:

• Try to avoid the sun during the midday hours, when it's strongest.
• Wear a wide-brimmed hat.
• Use sunscreen and a lip balm that protect against ultraviolet light.

Treating oral cancer

Doctors assess a cancer's growth and assign it a "stage." A stage 0 or stage I tumor is just in one place or has not gone far into nearby tissues. A stage III or IV tumor may have grown deep into or beyond surrounding tissues.

Treatment depends on where the cancer started and its stage. Surgery, the most common treatment, involves removing the tumor and some healthy tissue around it. In many cases, the surgeon can remove the tumor through the mouth. But sometimes, the surgeon will need to remove the tumor through the neck or jaw. If cancer cells have spread into the lymph nodes, the surgeon will remove them to try to prevent the cancer from spreading to other parts of the body.

One of the most exciting new developments in the treatment of oral cancer is the use of robotic surgery. Complex operations that took hours and were quite debilitating can now be performed with greater efficiency using robotic-assisted techniques.

Radiation therapy is the primary treatment for some small tumors. It uses high-energy x-rays to kill cancer cells. In some cases, patients who have surgery also receive radiation therapy to make sure that all cancer cells are destroyed. Even if it cannot cure the cancer, radiation therapy may relieve symptoms such as pain, bleeding, and trouble swallowing.

Doctors may prescribe chemotherapy to shrink tumors before surgery, or after surgery to ensure that all cancer cells are destroyed. If a tumor is too large to be operated on, chemotherapy and radiation therapy can ease symptoms.

If cancer is diagnosed at an earlier stage (stage I and II), the chances of a cure are much better. These tumors are less than 4 centimeters at the widest point and have not spread to lymph nodes. They are often treated with a combination of surgery, radiation therapy, and chemotherapy.

The treatment your doctor chooses may depend on the cancer's location. Surgery is usually the first choice if it isn't likely to affect your ability to speak and swallow. Radiation can irritate healthy tissue in your mouth or throat, but it is a better choice for some cancers.

Stage III and IV tumors are more advanced. These tumors are large, involve more than one part of the mouth, or have spread to lymph nodes. Usually they are treated with more extensive surgery, as well as radiation therapy, chemotherapy, or both. Some Stage III and IV oral cancers may also be treated with an immunotherapy drug called a checkpoint inhibitor. Certain Stage IV tumors may be treated with immunotherapy, targeted therapy, or both.

After the cancer has been treated, you may need therapy to regain the ability to speak and swallow. If you had extensive surgery, you may need cosmetic surgery, too.

When to call a professional

If you discover a lump or a discolored area in your mouth or on your tongue, see your doctor or dentist as soon as possible.

Prognosis

The earlier oral cancer is found, the better the prognosis. Most people with early-stage cancers have an excellent cure rate. For people with stage III or IV oral cancers, the prognosis is not as good.

Even after small cancers are cured, patients remain at risk of developing another cancer in their mouth, head, or neck. That's why follow-up exams are crucial.

Additional info

American Cancer Society (ACS)
http://www.cancer.org/

Cancer Research Institute
http://www.cancerresearch.org/

National Cancer Institute (NCI)
http://www.nci.nih.gov/

American Academy of Otolaryngology – Head and Neck Surgery
http://www.entnet.org/