Most commonly occurring cancers
Dr. VIKAS SHARMA
Cancer originates within a single cell and can be classified by the type of cell in which it originates or by the location of the cell. In India, around 5, 55,000 people died of cancer in 2010. Cancer cases related deaths are on the rise in J and K during past four years with the total of 11,815 cancer cases and 5,198 mortality cases have been reported in the State during the current year. At present more than 100 types of cancer are known, the most commonly occurring ones in J and K are oral, lung, breast and cervical cancer. A number of factors are responsible for promoting cancer, viz; physical, chemical, lifestyle, dietary, pharmacological, reproductive and genetic factors. DNA/RNA viruses and infectious diseases can also lead to cancer. Among the risk factors, the use of tobacco (cigarette, cigar, pipe or smokeless tobacco), unhealthy diet (rich in fatty foods) and physical inactivity (leading to obesity) are more likely to increase a person’s risk for cancer than the very low levels of pollutants in food, drinking water and air.
Oral cavity cancer often starts as a tiny, unnoticed white spot (leukoplakia) or red spot (erythroplakia) or sore anywhere in the mouth and can effect any area of the oral cavity including the lips, the lining inside the lips, cheek lining, tongue, the bottom of the mouth under the tongue, the small area behind the wisdom teeth, gum tissue, hard palate and soft palate, the tonsils and the back of the throat. The disease occurs in people over the age of 40, but can develop at any age. Erythroplakia occurs most often in people 60 to 70 years of age. Smoking cigarettes, cigars or pipes and chewing tobacco or dipping snuff accounts for 80 to 90 per cent of oral cancers. Spit tobacco is the significant cause of leukoplakia. Marijuana smoking is also a contributing factor to oral cavity cancer. Alcohol has been identified as a co – agent, most probably through a topical effect. The mucosal areas that are exposed to prolonged contact with alcohol are at greater risk of cancer development. Patients with vitamin A deficiency have been considered at high risk of malignant transformation of oral mucosa. More than 25 per cent of oral cancers occur in people who do not smoke and have no other risk factor. Symptoms of oral cancer include a sore in the mouth that does not heal, a white or red patch on the gums, tongue or lining of the mouth, a lump or thickening in the cheek, soreness or a feeling that something is caught in the throat, a colour change of the oral tissues and difficulty in chewing, swallowing, speaking or moving the jaw or tongue. Pain is usually not an early symptom of oral cancer. Surgery is the usual treatment to remove the tumor from the mouth. Radiation therapy is sometimes used instead of surgery for small tumors. Patients with large tumors may need both surgery and radiation therapy. Before surgery radiation therapy can shrink the tumor so that it can be removed and after surgery it is used to destroy cancer cells that may remain. Some patients also receive chemotherapy treatment with anti-cancer drugs.
Lung cancer takes many years to develop, but changes in the lung can begin almost as soon as a person is exposed to cancer causing substances, after which, a few abnormal cells may appear in the lining of the bronchi (the main breathing tubes) and continuation of exposure leads to the appearance of more abnormal cells. These cells may be on their way to becoming cancerous and forming a tumor. Non – small cell and small cell are the two major types of lung cancer. The small cell lung cancer also called oat cell cancer, accounts for about 20 per cent of all lung cancers. In its early stages, lung cancer usually does not cause symptoms. When symptoms occur, the cancer is often advanced, which include chronic cough, coughing up blood, shortness of breath, fever without a known reason, loss of weight and appetite, wheezing, hoarseness and chest pain. Chest radiography is probably the most valuable tool of diagnosis of lung cancer. Lung cancer is treated by surgery, radiotherapy and chemotherapy. Surgery is used in limited stages of the disease and the type of surgery depends on where the tumor is located in the lung. Some tumors cannot be removed because of their size or location. Radiation therapy is used in combination with chemotherapy to offer relief from pain or blockage of airways. 4 – Ipomeanol, a naturally occurring pulmonary toxin, is the first antitumor drug targeted specially against lung cancer.
Breast cancer, a leading cause of mortality in women aged between 40 to 55, but is quite uncommon in males accounting for less than 1 per cent of all cases. The possible causes of increased risk of developing breast cancer are increasing age, family history, exposure to female reproductive hormones, dietary factors, benign breast diseases and environmental factors. Early age at menarche and late age at menopause also increase the risk of developing the disease. Women with first child, when older than 30 years are at increased risk. The risk is more frequent with nulliparous (late age at first full term pregnancy) than multiparous women. The symptoms which indicate the presence of breast cancer include bleeding from nipple, rash around the nipple, change in size and shape of breast, prominent veins around the breast, lump in the armpit, swelling of arms, ulceration of skin and symptoms of secondary tumors elsewhere. In advanced breast cancer, in drawing of skin and dimpling, inversion of nippleis observed. Adriamycin (doxorubicin), an anthracycline antibiotic, is the most active single agent against the disease. Synthetic antiestrogen, tamoxifen, can also reduce the incidence of invasive breast cancer in healthy women. Diet high in fruits and vegetables may decrease breast cancer risk. Radiation therapy still appears to be the most effective means of providing symptomatic relief.
Cervical cancer is the most common malignancy in women among the main gynecological cancers originate from the cervix, endometrium and ovary. It is the second leading cause of cancer deaths in women aged between 20 to 39, after breast cancer. When cancer occupies both the cervix and vagina without the junctional area (the fornix), the cancer extending to the exocervix is recongnised as a cancer of the cervix. The risk of cervical cancer is increased in prostitutes and in women who have first coitus at a young age, have multiple sexual partners, have sexually transmitted diseases, have high number of children or bear children at a young age and excessive douching. Promiscuous sexual behaviour in male partners is also a risk factor. Second wives of men whose first wives had cervical cancer may also be at increased risk. A possible increase in the risk of invasive cervix cancer can also be found in HIV- positive women. Other factors include cigarette smoking, immunodeficiency, vitamin A / C deficiency and oral contraceptive use. The earliest symptom of invasive cervical cancer is usually abnormal vaginal bleeding and other symptoms include irregular menses, postcoital bleeding etc. Treatment consists mainly of surgery and radiation. Chemotherapy is also proceeded in combination with surgery or radiation, for advanced cases continuous infusion of 5-Fluorouracil and Paclitaxel (taxol) also produced high response rates.