By Dr. Niti Raizada
The short answer to that is “Ofcourse not!” The long answer to that is to understand why not?
But first, why do non-smokers get lung cancers? The causes can be because of second-hand smoke – ie constant exposure to others smoking. Studies have shown that upto a third of the non-smokers getting lung cancer is because of secondhand smoke. Other causes are exposure to lot of industrial air pollutants, asbestos and radon, and those who have genetic predisposition for lung cancer.
Lung Cancer odds increases 20 -25 fold if one is a smoker. So the disparity is huge, between smokers and non smokers. What exactly happens to the lungs of a smoker? The cells lining the lungs are most likely to have the cancerous change & it was long suspected that these cells undergo genetic mutations when exposed to tobacco smoke. Recently scientists used a process called Single-Cell whole genome sequencing to examine cells lining the lungs of smokers and non smokers ranging from teens to mid 80’s year old & found evidence that smokers had far more genetic mutations than non smokers. This confirmed the hypothesis of the genetic changes as the most likely cause setting off the process of cancers among smokers. It is estimated that 10-20% of all smokers can potentially get cancer but very few non smokers do.
Does that mean there is a linear correlation between years of smoking and propensity to get lung cancer? Well, yes, and no. Yes, the number of mutations detected in smokers lung cells increased in direct proportion to number of “pack-years” smoked. Pack-year is defined as the equivalent of smoking one pack a day for a year. Studies in the West has shown that mutations were most within 23 pack-years. Some have the propensity to develop cancer very early, while some can keep “smoking like a chimney” into old age and the mutations do not show up. So does that mean that if one has smoked beyond the 23 pack-years the odds of getting lung cancer reduces and hence can continue smoking? No way! The odds of getting lung cancer is still high and much higher than a non smoker. Besides which, tobacco smoking also leads to other cancers like Throat, Liver, GI Tract, Bladder cancers. Non Cancer issues like COPD (Chronic Obstructive Pulmonary Disease) – which begins as a benign smokers cough but leads to Chronic Bronchitis and a terrible quality of life where one is often breathless, constant irritating cough, bringing out copious phlegm, and limiting physical exertion as there is air hunger; just makes quality of life unbearable, cancer or no cancer. Also the risk for Coronary Heart Disease leading to heart attacks & vascular diseases leading to strokes and gangrene of extremities are high.
Lung Cancer screening in mass population is now restricted to smokers for various reasons, mainly the high incidence among smokers, the need for X rays – and exposing non smokers needlessly to this, the high cost involved and the logistics of handling so many. Genetic screening to check predisposition to lung cancer is not routine and nor desirable as quitting smoking is the only sensible way out of getting away from the entire disease spectrum caused by tobacco smoke inhalation
A Good Oncology Practice in leading hospitals has a program to help smokers quit smoking. It is very practical and huge number have benefitted from it. Now is always a right time to quit smoking, and take that step, make that call to institutions who have this program and earnestly take care of your body, which when I last checked is the only one we have in this life!
(The author is a Director, Medical Oncology and Hemato-Oncologist, Fortis Group of Hospitals, Richmond Road, Bangalore. The article is for informational purposes only. Please consult medical experts and health professionals before starting any therapy, medication and/or remedy. Views expressed are personal and do not reflect the official position or policy of the FinancialExpress.com.)
