Almost all oral cancers start in the cells lining the oral cavity (the mouth). These cells, which are flat and scale-like, are called squamous cells. When a cancer begins in these cells, it is known as a squamous cell carcinoma. The structures of the oral cavity play an important role in speech, chewing, taste and swallowing. Oral cancer is part of a group of cancers called head and neck cancers.
It is estimated that 3400 new cases of oral cancer will be diagnosed in Canada in 2010.
Risk factors may increase a person’s chance of developing oral cancer. The factors that increase the risk of developing oral cancer include:
- chewing betel nut, also known as paan
- sun and ultraviolet radiation (for lip cancer only)
- previous head and neck cancer
- human papillomavirus (HPV) infection
- precancerous conditions
Early detection means finding a cancer or precancerous condition at an early stage. In most cases, finding cancer early increases the chances of successful treatment.
There is no screening test for oral cancer. Therefore, recognizing symptoms and getting regular checkups are the best ways to detect oral cancer early. The sooner signs and symptoms are reported, the sooner a doctor can diagnose and treat the cancer.
People who have a higher than average risk for oral cancer should discuss an individual plan for testing with their doctor. They should have a regular mouth checkup with their family doctor and dentist. A careful routine examination of the mouth can often detect early precancerous changes.
Signs and symptoms
Other health conditions can have the same signs and symptoms as oral cancer, so having any of the following symptoms does not necessarily mean a person has cancer. However, it is important to see a doctor about:
- an ulcer or sore in the mouth that doesn’t heal
- a lump in the lip, mouth, gums, tongue, roof or tonsil
- thickening in the cheek
- bleeding in the mouth
- pain in the mouth that doesn’t go away
- loose teeth
- dentures that no longer fit
- slurred speech
- swollen saliva glands
- swollen lymph nodes in the neck
White patches (leukoplakia) or red patches (erythroplakia) on the lips or in the mouth are precancerous conditions that may become cancerous.
Diagnostic tests will be done if the signs and symptoms of oral cancer are present, or if the doctor suspects oral cancer. These tests may include:
- complete physical examination
- laboratory tests
- imaging tests
Additional tests, such as x-rays, ultrasounds and scans, may be done to determine the stage (how far the disease has progressed).
Pathology and staging
When oral cancer has been diagnosed, tests will be done to find out:
- the type of oral cancer
- The most common form of oral cancer is squamous cell carcinoma and it accounts for over 90% of all oral tumours.
- the stage of the cancer (how far the cancer has progressed)
- The stage is based on the tumour size and whether or not the cancer is in any lymph nodes or has spread to other areas of the body.
- the grade of the tumour (how abnormal the cancer cells look and behave)
Although oral cancer can spread to lymph nodes in the neck, this cancer does not usually spread to other body sites. However, some of the most common sites where oral cancer can spread include the:
A person’s prognosis depends on:
- the stage of the cancer
- tumour characteristics
- tumour size
- grade of the cancer
- other medical conditions
- the patients overall health and well-being
Each person with oral cancer will have a treatment plan designed for them by their healthcare team. The team will recommend treatment options based on the specific characteristics of the cancer and the unique needs of the person. A treatment plan for oral cancer may include one or more of the following.
Surgery is the most common treatment for oral cancer. Surgery is used to:
- potentially cure the cancer or to remove as much of the tumour as possible
- remove the lymph nodes in the neck
- reconstruct areas of the mouth or jaw after major surgery
Radiation therapy can be used as the primary treatment for oral cancer or can be given following surgery. It can also be combined with chemotherapy. It may be given to relieve pain in cases of advanced cancer. The types of radiation therapy for oral cancer may include:
- external beam radiation therapy
- brachytherapy (internal radiation therapy)
- IMRT (intensity-modulated radiation therapy)
Chemotherapy used alone will not cure oral cancer. However, it can be combined with other treatments to be part of a treatment plan. The most common chemotherapy drugs used to treat oral cancer include:
A cancer diagnosis can lead to many challenges for people with cancer and their families. Each person’s experience will be different because their cancer, treatment and recovery are different. A person with oral cancer may have concerns about:
- follow-up after treatment is finished
- It is important that people with oral cancer have regular follow-up visits after they are finished treatment. These visits may be frequent at first, but could taper to less frequent visits depending on the person’s situation.
- Reconstructive surgery is usually performed at the time the cancer is removed, but more reconstructive surgery may be needed to restore a person’s appearance and to improve chewing, swallowing and speaking.
- rehabilitation and adjustment
- Rehabilitation is an important part of returning to the activities of daily living after cancer treatment. The concerns for each person will vary depending on their own situation. Some of the issues will be about self-esteem, body image, speech therapy, psychosocial support or quality of life.
- sore mouth (mucositis)
- Mucositis causes painful sores and inflammation in the mouth, including the tongue, gums, back of the throat and the lips. Pain relievers, good mouth care and diet may help relieve symptoms.
- dry mouth (xerostomia)
- Dry mouth occurs because of a decrease in the quality and amount of saliva due to treatment. Diet, good hygiene, synthetic saliva products and regular dental checkups may be helpful to manage this side effect of treatment.
- dental cavities
- Dental cavities can occur as a result of treatment. Regular visits to the dentist for complete dental exams, cleaning and treatment of any complications will help to manage this side effect of treatment.
- difficulty swallowing (dysphagia)
- It may be difficult to swallow because of tumour growth, surgery, dry mouth (xerostomia) related
to radiation and sore mouth (mucositis) due to chemotherapy. Diet modifications, exercises and tube feeding may be used to help manage this side effect.
- pain management
- Pain can occur as a result of treatment for oral cancer. Pain can be managed through medications and other techniques such as massage or relaxation.
- taste changes
- Taste changes can occur with oral cancer or can be a side effect of treatment. Radiation treatment, particularly in the elderly patient, can result in long-term taste changes. Taste changes can be managed through mouth care and changes in diet to prevent loss of appetite (anorexia), weight loss and malnutrition.
- It may be difficult to open the mouth following treatment because of scar tissue in the mouth joint and muscles used for chewing. Exercises can help to prevent this problem.
- Radiation to the neck or upper chest may cause decreased thyroid function, which is known as hypothyroidism. Daily medication may be needed to regulate the thyroid gland.