Home About Cancer Risk Factors

The causation of cancer is considered multifactorial and results from the interplay between the genetic factors, environmental and behavioral factors. The various major risk factors for cancer are;

1) Tobacco - involved in cancers of lung, mouth, larynx, esophagus, pancreas, stomach, colon, cervix, kidney, and bladder. Smoking may lead to an elevated risk of liver and prostate cancer, as well as leukemia. Secondhand smoke causes lung cancer in nonsmokers. Smokeless tobacco causes oral cancer. PAH, N-nitrosamines, aromatic amines, 1,3-butadiene, benzene, aldehydes, and ethylene oxide are carcinogens present in tobacco smoke.
2) Obesity and lack of Physical activity- Sedentary lifestyle with lack of physical activity and resultant obesity increase the risk of cancer of colon, breast, endometrium, esophagus, renal cell carcinoma, pancreas, gall bladder etc. Even 30min of activity per day significantly reduces the risk.
3) Viruses- RNA viruses involved in causation of cancer are Human T-lymphotropic virus (HTLV), human immunodeficiency virus (HIV) and Hepatitis C virus .HTLV causes adult T cell leukemia. Non Hodgkin lymphoma, Kaposi sarcoma, cervical cancer and anal cancer are common in AIDS patients. HCV is associated with hepatocellular carcinoma.
4) Chronic inflammatory conditions like lichen scleroses, reflux esophagitis, asbestosis, chronic pancreatitis, inflammatory bowel diseases like ulcerative colitis, liver cirrhosis etc.
5) Chemical factors- Lung (tobacco smoke, arsenic, asbestos, coal tar etc.), Pleura (asbestos), Oral cavity and esophagus(tobacco smoke, alcohol), Stomach(smoked, salted and pickled foods), bladder(tobacco smoke, benzidine)
6) Dietary factors- Alcohol is the best established dietary risk factor for cancer. It increases the risk of cancers including those of the liver, esophagus, pharynx, oral cavity, larynx, breast, and colorectum in a dose-dependent fashion. Dietary fat is associated with cancer of breast, colon, prostate and endometrium. Intake of food and vegetables in higher amounts reduces the risk of cancer.

 Risk factor for cancer varies with type of cancer. In general, there are certain common risk factors applicable to many cancers

  1. Tobacco use
  2. Hereditary
  3. Exposure to chemical carcinogens
  4. Exposure to ionizing radiation
  5. Sedentary life habit
  6. Obesity
  7. Dietary factors- high fat diet