India, July 26 -- Lung cancer was almost synonymous with smoking for decades. However, in the clinics of today, doctors are increasingly diagnosing lung cancer in people who have never lit a cigarette. Many are women, younger adults, and people who do not have any apparent lifestyle risk factors. This is one of the largest changes that respiratory physicians and oncologists are seeing. Dr Harshil Alwani, consultant, Pulmonology, Narayana Hospital, Jaipur, explains the risk to non-smokers.

Dr Harshil Alwani said, "Although smoking is still the primary cause of lung cancer worldwide, a large percentage of lung cancer cases are now in never-smokers." Indeed, if lung cancer in never-smokers was a disease on its own, it would be one of the to...