Lifestyle, not luck, causes most cancers
Malathy Iyer
Mumbai:


American scientists recently stirred a hornet's nest by linking bad luck to the occurrence of cancer, but Indian oncologists would rather turn the equation on its head to say that as far as cancer is concerned, it's lucky to be in India.
Doctors tout two reasons.First, most cancers here are linked to lifestyle and environment, say doctors, and have little to do with bad luck. It means malignancies can be prevented to an extent. The food we eat, the air we breathe and the choices we make -be it to smoke, drink alcohol or not exercise regularly -are more linked to our chances of getting cancer. “Tobacco is the cause for 40% to 50% of cancers in India as it increases the risk of cancers of the oral cavity, lungs, gastrointestinal tract and urinary bladder,“ said Dr S D Banavali, who heads medicinal oncology in Tata Memorial Hospital in Parel.

Second, as Tata Memorial Hospital director Dr Rajendra Badwe says, the rate of cancers in India is very low in comparison to the West. “The incidence of cancer is 90 per 1,00,000 persons in Indian cities and 45 per 1,00,000 in rural India. The West, on the other hand, has a rate of 350 per 1,00,000,'' he said.

The happy picture does get blurry when one considers that India's population is so high that even a low cancer rate means a high number of patients. On the eve of World Cancer Day on February 4, the fact is that 10 lakh Indians get diagnosed with cancer every year while seven lakh others succumb to it. American scientists recently linked bad luck to the occurrence of cancer, but Indian oncologists would say that as far as cancer is concerned, it's lucky to be in India.

Cancer surgeon Pankaj Chaturvedi said, “By blaming genes, we cannot suppress the fact that the majority of cancers are caused by industry. Tobacco is a big industry, ditto with the fast food industry that is making us obese and thus increasing the risk of cancer.“

Theories about the exact reasons for cancer and why it affects certain people and not others has eluded scien tists. Genetic reasons hold true only for around 5% of all cancers. The most heartwrenching cancers--read pediatric cancers--account for only 3% of the total incidence. Moreover, what about cases in which a woman teacher, who has never smoked or chewed tobacco, gets oral cancer or a young father gets brain cancer?
There seems to be no common thread linking all cancers.

Cancer is a complex disease. Cancer surgeon Dr P Jagannath from Lilavati Hospital, Bandra, said, “Human cells, a trillion of them, keep dividing while fatihfully replicating a complex DNA. While this is a super-precise process, even a `cell' can make errors.“ The cell, though, has a remarkable ability to either fix the problem or eliminate the bad gene. “However, some of the changes can occur in critical parts of the DNA, near the oncogenes, which trigger uncontrolled growth and replication of cells that is `cancer',“ he added.

Dr Jagannath has another take: “What do we then do about the `bad luck' or the `bolt from the blue' genetic mutation? Very few of them (mutations) are hereditary and can be detected in families that have clusters of cancers like colon or breast cancer but many of them are again `random unfortunate events'.