New Delhi: Lung cancer, long known to affect smokers, is seeing a significant rise in people who do not smoke, said doctors on Monday, raising concern over the shift.

Health experts have identified increased exposure to air pollution as the primary culprit behind this disturbing trend, underscoring the grave impact of environmental factors on public health.

A recent study published in the Lancet’s eClinical Medicine Journal revealed that a majority of lung cancer patients in India are non-smokers. The study also highlighted the importance of early diagnosis, as lung cancer cases are now appearing in India about 10 years earlier than in Western countries.

“India’s lung cancer demographic presents a unique and concerning picture, with a rising incidence among younger individuals and an increasing number of cases occurring in non-smokers. Traditionally, lung cancer has been strongly associated with smoking, but we are witnessing a shift, especially in urban populations,” Dr. Prasad Adusumilli, Thoracic Surgeon and Cellular Therapist, Memorial Sloan Kettering Cancer Center (MSK), US, told IANS.

Adusumilli added that non-smokers, particularly women, are increasingly diagnosed with lung cancer around 10 years earlier than their Western counterparts, often with no history of smoking.

“This may be linked to various risk factors, including exposure to environmental pollutants, genetic predisposition, and lifestyle factors,” he explained.

Lung cancer is also the leading cause of cancer-related deaths globally, with increasing cases among non-smokers, especially women and Asian populations.

India reports about 75,000 new cases of lung cancer every year. Worryingly, a considerable number of these patients, estimated to be around 60%, are diagnosed at advanced stages, when the cancer has already spread to other parts of the body, making it more difficult to treat.

“Non-smoker lung cancer (LCINS) mainly presents as adenocarcinoma, affecting peripheral lung tissues. Key risk factors include air pollution, radon exposure, indoor cooking fumes, and second-hand smoke,” said Dr Jagadishwar Goud Gajagowni, an oncologist at a Hyderabad-based hospital.

“Environmental pollutants like fine particulate matter (PM2.5) in urban areas and radon in homes significantly contribute to risk. Poor indoor air quality from cooking with solid fuels in poorly ventilated spaces also poses a danger, especially in developing regions. Passive smoking further elevates risks, particularly in areas with high smoking rates among men, the doctor noted.

Significant advancements in lung cancer treatments have been made. Minimally invasive surgical approaches and radiation therapies offer patients a less invasive, more targeted approach, resulting in reduced recovery times and fewer side effects.

Further, “the development of targeted therapies has revolutionised the treatment landscape, offering more personalised and effective options for patients based on the molecular profile of their tumours,” Adusumilli said.