Mouth (Oral) Cancer Home A-Z Health Information Health Library A-Z Mouth (Oral) Cancer Overview Oral cancer, often categorised as head and neck cancers, refers to cancers developing in one or more of the following parts of the oral cavity: LipsThe floor and/or roof of the mouthGumsTongueInner lining of the cheek Causes and risk factors Mouth cancers form as a result of changes in the DNA in cells on the lips or in the mouth; these changes dictate the cells to continue division and growth in situations where apoptosis, i.e., programmed cell death to get rid of abnormal/unnecessary cells, usually occurs. The abnormal mouth cancer cells accumulate to form a tumour. The causes underlying the changes in squamous cells that ultimately lead to mouth cancer have not yet been identified; however, the factors that have been reported to increase the risk of developing mouth cancer are as follows:Frequent use of tobacco products, including cigarettes, cigars, pipes, chewing tobacco, and snuffHeavy alcohol consumptionExposure of the lips to excessive sunlightThe human papillomavirus (HPV), a sexually transmitted virusA weakened immune system1 Symptoms A sore on the mouth or lip that does not healA reddish or whitish patch or a growth or lump within the mouthLoose teethJaw and/or ear painPain or difficulty in swallowingIf the afore-mentioned symptoms are observed to persist and last more than two weeks, patients are advised to visit their doctor as soon as possible. Diagnosis The following tests are used to diagnose mouth cancer: Physical examination: The dentist checks the mouth and lips to detect abnormalities and/or areas that cause pain/discomfort, such as white patches (leucoplakia) and/or sores2Biopsy: A piece of tissue or fluid is excised or aspirated from the body to be tested in the laboratory. Treatment The stage and location of the cancer and the overall health and personal preference of the patients determine the therapeutic modality to be used for mouth cancer treatment. A patient may require one or a combination of the following treatments:Surgical resection: The oral surgeon may excise the tumour; to ensure the removal of all the tumour cells, the margin of healthy tissues may also be removed. If the cancer has been observed to have spread to the cervical lymph nodes, they are also dissected. Usually, after surgical resection, to help the patient regain the ability to eat and talk, reconstructive surgery to repair and rebuild the tissues in the mouth is recommended. Radiation therapy: Cancer cells are killed by subjecting them to treatment with high-energy waves or particles, such as gamma rays, X-rays, electrons, or protons. Often, radiation therapy is used post-surgery; however, sometimes, for patients with early-stage mouth cancer, it may be used alone. Chemotherapy: Cancer cells are killed using chemicals, i.e., chemotherapy drugs. These drugs are often administered alone or in combination with other drugs/therapeutic modalities for cancer treatment. As chemotherapy has been reported to exert synergistic effects with radiation therapy, enhancing the efficacy of the latter, the two are often administered as a combination.Targeted drug therapy: Targeted drugs that alter specific growth-related aspects of cancer cells can be used to eliminate these cells. Often, these drugs are used in combination with chemotherapy/radiation therapy or alone.Immunotherapy: Immunotherapy is based on fighting cancer using the patient’s immune system. Because cancer cells often demonstrate immune evasion, i.e., escape from the immune system, by various techniques, such as the production of specific proteins that “blind” the immune system, the body's immune system may fail to recognise and kill these cells. Immunotherapy is based on interfering with this “immune evasion” process. Generally, immunotherapy-based treatments are reserved for patients with advanced-stage mouth cancers for which standard treatments have been ineffective4.