What is Oral Cancer?
Oral cancer is part of a group of cancers called head and neck cancers. Oral cancer can develop in any part of the oral cavity or oropharynx. Most oral cancers begin in the tongue and in the floor of the mouth. Almost all oral cancers begin in the flat cells (squamous cells) that cover the surfaces of the mouth, tongue, and lips. These cancers are called squamous cell carcinomas. When oral cancer spreads (metastasizes), it usually travels through the lymphatic system. Cancer cells that enter the lymphatic system are carried along by lymph, a clear, watery fluid. The cancer cells often appear first in nearby lymph nodes in the neck.
Cancer cells can also spread to other parts of the neck, the lungs, and other parts of the body. When this happens, the new tumor has the same kind of abnormal cells as the primary tumor. For example, if oral cancer spreads to the lungs, the cancer cells in the lungs are actually oral cancer cells. The disease is metastatic oral cancer, not lung cancer. It is treated as oral cancer, not lung cancer. Oral cancer happens when there is something wrong or unusual in the normal cell lifecycle. This abnormal working of the cell lifecycle results in uncontrollable growth and reproduction of these cells.
Some of the risk factors for Oral Cancer include:
- Tobacco use
- Heavy alcohol use
- Human Papilloma Virus (HPV) infection
- High levels of sun or ultraviolet (UV) light exposure
- Personal history of oral cancer
- Betel quid and gutka use
- Diets low in fruits and vegatables
- Weakened immune system
Common Symptoms and Signs that Oral Cancer may be present:
- Abnormal patches inside the mouth or on your lips
- Sore on the lip or in the mouth that doesn’t heal
- Unexplained bleeding in the mouth
- Loose teeth
- Difficulty or pain when swallowing
- Difficulty wearing dentures
- A lump in your neck
- An earache that doesn’t go away
- Numbness of lower lip and chin
• Stage 0 (Carcinoma in Situ) : This stage is considered as the pre-cancer stage. In this stage, there are cancer cells that are inside the lining of the mouth that have not yet spread. If this stage is left untreated then it can develop into an invasive cancer.
• Stage 1 : This is considered as the early stage of invasive cancer. Now the cancer has started to develop through the mouth lining and also in the deep tissues below. The cancer has not spread close to other organs, tissues or lymph nodes and this cancer is not beyond 2 cm across.
• Stage 2 : In the second stage, the tumor is more than 2cm but is less than 4cm. Other organs or lymph nodes are remains unaffected by this cancer.
• Stage 3 : One or more conditions are true in this stage- first; the tumor is of any size that has spread to 1lymph nodes on the same side of the neck. Second, the cancer is more than 4 cm that has not spread to any part of the body or to any lymph nodes.
• Stage 4 : This stage is known as the advanced stage of oral cancer that is categorized into three stages.
o Stage 4A : This stage is marked by the growth of the cancer through the tissues around the mouth and lips. At this stage, it is possible that lymph nodes may or may not possess any cancer cells.
o Stage 4B : This stage is marked by the spread of the cancer to any lymph node which is bigger than 6 cm or to lymph nodes on both neck sides, or to more than one lymph node on the same side of the neck.
o Stage 4C : This stage is marked by the spread of the cancer to different body parts that include bones or lungs.
Diagnosis of Oral Cancer
A number of tests are performed for diagnosing mouth cancer that include:
• Biopsy : A small tissue sample is taken in biopsy that is further sent to a laboratory for determining the type of cells and whether they are cancerous or non-cancerous.
• Throat and Mouth Examination : A special instrument known as flexible laryngoscope is used for viewing within the throat and mouth.
Certain other tests are also required for determining the spread of the cancer. These tests are:
• A Barium Swallow and Meal Test : This test requires a patient to swallow a drink having barium. An x-ray will present images of abnormal growths in the digestive system down to the stomach.
• X-rays : X-rays are done of the lower and upper jaw or a chest x-ray can also be done.
• Endoscopy : This test helps in viewing the body from within. An endoscope (a narrow and flexible tube having a telescopic camera) is used for performing this test.
• Certain other biopsies of nearby lymph nodes are also done.
Surgery for mouth cancer may include:
• Surgery to remove the tumor Your surgeon may cut away the tumor and a margin of healthy tissue that surrounds it. Smaller cancers may be removed through minor surgery. Larger tumors may require more-extensive procedures. For instance, removing a larger tumor may involve removing a section of your jawbone or a portion of your tongue.
• Surgery to remove cancer that has spread to the neck If cancer cells have spread to the lymph nodes in your neck, your surgeon may recommend a procedure to remove cancerous lymph nodes and related tissue in the neck (neck dissection).
• Surgery to reconstruct the mouth After an operation to remove your cancer, your surgeon may recommend reconstructive surgery to restore the appearance of your face or to help you regain the ability to talk and eat. Your surgeon may transplant grafts of skin, muscle or bone from other parts of your body to reconstruct your face. Dental implants may replace your natural teeth.
• Biological Therapy : The activity of the cancer cells is changed with the help of biological therapy. A type of biological therapy is known as Cetuximab that is also referred to as a monoclonal antibody. The surface of the cancer cells that triggers the development of cancer cells is blocked with the help of Cetuximab.
• Radiotherapy : Radiotherapy uses doses of radiation to kill cancerous cells. It may be possible to remove the cancer using radiotherapy alone, but it is usually used after surgery to prevent the cancer from re-occurring.
• Internal radiotherapy : Internal radiotherapy is a type of radiotherapy often used to treat cancers of the tongue that are in their early stages. It involves sticking radioactive wires or needles directly into the tumour while you are under a general anaesthetic (put to sleep). The wires or needles then release a dose of radiation into the tumour.
• Chemotherapy : Chemotherapy is often used in combination with radiotherapy when the cancer is widespread, or if it is thought there is a significant risk of the cancer returning.Chemotherapy involves the use of powerful cancer-killing medicines.