Mouth cancer

Oral cancer, also known as mouth cancer, is cancer of the lining of the lips, mouth, or upper throat. In the mouth, it most commonly starts as a painless white patch, that thickens, develops red patches, an ulcer, and continues to grow. When on the lips, it commonly looks like a persistent crusting ulcer that does not heal, and slowly grows. Other symptoms may include difficult or painful swallowing, new lumps or bumps in the neck, a swelling in the mouth, or a feeling of numbness in the mouth or lips. Oral cancer, also known as mouth cancer, is cancer of the lining of the lips, mouth, or upper throat. In the mouth, it most commonly starts as a painless white patch, that thickens, develops red patches, an ulcer, and continues to grow. When on the lips, it commonly looks like a persistent crusting ulcer that does not heal, and slowly grows. Other symptoms may include difficult or painful swallowing, new lumps or bumps in the neck, a swelling in the mouth, or a feeling of numbness in the mouth or lips. Risk factors include tobacco and alcohol use. With both tobacco and drinking alcohol the risk of oral cancer is 15 times greater. Other risk factors include HPV infection, chewing paan, and sun exposure on the lower lip. Oral cancer is a subgroup of head and neck cancers. Diagnosis is made by biopsy of the concerning area, followed by investigation with CT scan, MRI, PET, and examination to determine if it has spread to distant parts of the body. Oral cancer can be prevented by avoiding tobacco products, limiting alcohol use, sun protection on the lower lip, HPV vaccination, and avoidance of paan. Treatments used for oral cancer can include a combination of surgery (to remove the tumor and regional lymph nodes), radiation therapy, chemotherapy or targeted therapy. The types of treatments will depend on the size, locations, and spread of the cancer taken into consideration with the general health of the person. In 2018, oral cancer occurred globally in about 355,000 people, and resulted in 177,000 deaths. Between 1999 and 2015 in the United States rate of oral cancer increased 6% (from 10.9 to 11.6 per 100,000). Deaths from oral cancer during this time deceased 7% (from 2.7 to 2.5 per 100,000). Oral cancer has an overall 5 year survival rate of 65% in the United States as of 2015. This varies from 84% if diagnosed when localized, compared to 66% if it has spread to the lymph nodes in the neck, and 39% if it has spread to distant parts of the body. Survival rates also are dependent on the location of the disease in the mouth. The signs and symptoms of oral cancer depend on the location of the tumor but are generally thin, irregular, white patches in the mouth. They can also be a mix of red and white patches (mixed red and white patches are much more likely to be cancerous when biopsied). The classic warning sign is a persistent rough patch with ulceration, and a raised border that is minimally painful. On the lip, the ulcer is more commonly crusting and dry, and in the pharynx it is more commonly a mass. It can also be associated with a white patch, loose teeth, bleeding gums, persistent ear ache, a feeling of numbness in the lip and chin, or swelling. When the cancer extends to the throat, there can also be difficulty swallowing, painful swallowing, and an altered voice. Typically, the lesions have very little pain until they become larger and then are associated with a burning sensation. As the lesion spreads to the lymph nodes of the neck, a painless, hard mass will develop. If it spreads elsewhere in the body, general aches can develop, most often due to bone metastasis. Oral squamous cell carcinoma is a disease of environmental factors, the greatest of which is tobacco. Like all environmental factors, the rate at which cancer will develop is dependent on the dose, frequency and method of application of the carcinogen (the substance that is causing the cancer). Aside from cigarette smoking, other carcinogens for oral cancer include alcohol, viruses (particularly HPV 16 and 18), radiation, and UV light. Tobacco is the greatest single cause of oral and pharyngeal cancer. It is a known multi-organ carcinogen, that has a synergistic interaction with alcohol to cause cancers of the mouth and pharynx by directly damaging cellular DNA. Tobacco is estimated to increase the risk of oral cancer by 3.4-6.8 and is responsible for approximately 40% of all oral cancers. Some studies in Australia, Brazil and Germany pointed to alcohol-containing mouthwashes as also being potential causes. The claim was that constant exposure to these alcohol-containing rinses, even in the absence of smoking and drinking, leads to significant increases in the development of oral cancer. However, studies conducted in 1985, 1995, and 2003 summarize that alcohol-containing mouth rinses are not associated with oral cancer. In a March 2009 brief, the American Dental Association said 'the available evidence does not support a connection between oral cancer and alcohol-containing mouthrinse'. A 2008 study suggests that acetaldehyde (a breakdown product of alcohol) is implicated in oral cancer, but this study specifically focused on abusers of alcohol and made no reference to mouthwash.