CAUSES OF CANCER AND CANCER PREVENTION
Estimates show that annually there are over 14 million cancer cases and 8 million cancer deaths worldwide, overwhelming evidence shows that many malignancies are preventable.
Multiple modifiable cancer risk factors have been identified --
(1)Tobacco -Tobacco use is the most preventable cause of cancer and accounts for 21 percent of worldwide total cancer . It is the strongest risk factor for lung cancer, increasing risk 10- to 20-fold. Smoking is also implicated as a risk factor for leukemia ,cancers of the oral cavity, nasal cavity, paranasal sinuses, nasopharynx, larynx, esophagus, pancreas cancer, liver cancer, stomach cancer, cervix cacner, kidney cancer, large bowel cancer, and bladder cancer.
(2)Obesity -Excess weight is associated with an increased risk of many types of cancer. Obesity has been associated to cause 20 percent of all malignancies . Loss of excess weight has a cancer preventive effect in many cancers, including esophageal adenocarcinoma, gastric cardia, colorectal, hepatocellular, endometrial cancer, ovarian cancer, gallbladder, pancreatic cancer, renal cell cancer, thyroid cancer, and postmenopausal breast cancers, multiple myeloma, and meningioma.
(3)Alcohol -Excess alcohol consumption increases the risk of multiple cancers. Alcohol act as an irritant, causing increased cell production; as a transporter carrying carcinogens; as an inhibitor of DNA methylation or as a prometabolite for identified carcinogens such as acetaldehyde .
(4)Diet -High intake of dietry fat ,red meat is associated with cancer risk.Diet low in fiber ,fresh fruits and vegetables has been implicated in cancer causation .
(5) Inactivity -Decreased physical activity appears to increase the risk for cancer , a sedentary lifestyle is associated with 5 percent of cancer deaths, lack of daily exercise increases the cancer risk .
(6)Infections - It is estimated that 17 percent of all new cancers worldwide are due to infections . Viruses may increase cancer risk .
(6.1)Human papillomavirus (HPV) with cervical and other anogenital cancers
(6.2)Hepatitis B (HBV) and C (HCV) with hepatocellular carcinoma )
(6.3)Human T-cell lymphotropic virus (HTLV-I) with adult T-cell leukemia
(6.4)Human immunodeficiency virus (HIV-I) with Kaposi sarcoma as well as with non-Hodgkin lymphoma
(6.5)Human herpes virus 8 (HHV-8) with Kaposi sarcoma and primary effusion lymphoma
(6.6)Epstein-Barr virus (EBV) with Burkitt lymphoma
(6.7)The bacterium Helicobacter pylori with gastrointestinal malignancies including gastric cancer and mucosa-associated lymphoid tissue (MALT) lymphomas
(6.8)Liver flukes with cholangiocarcinoma and hepatocellular carcinoma
(7) Radiation – Ionizing Radiation from any source and ultraviolet radiation from sun exposes for many cancers.
(8)Urban air pollution- Diesel exhaust and particulate matter air pollution have been associated with increased risk of lung cancer. These are discussed elsewhere
(9)Use of solid fuels .
(10)Contaminated injections in health care settings – Trasmission of infection like HIV,Hepatitis B and C
(13)Food Adulteration – Adultereted Milk ,Paneer ,artificial fruit and vegetable ripeners use .
How to prevent cancer –
- Avoid tobacco
- Be physically active- Regular exercise and yoga
- Maintain a healthy weight
- Take a diet rich in fruits, vegetables, and whole grains and low in saturated/trans fat, red meat, and processed meat.
- Avoid alcohol
- Protection against sexually transmitted infections.
- Vaccination for girls and boys against HPV.
- Avoid excess sun exposure.
- Screening for breast, cervical, and colorectal cancer regularly .