Mumbai’s lung cancer burden rising among non-smokers: report

The report links this trend to air pollution, biomass fuel exposure, occupational hazards, tuberculosis overlap and unequal access to timely care.

Dr Atul Budukh, Professor of Epidemiology at Tata Memorial Centre and lead author of the report, said the findings challenge long-held assumptions about lung cancer. “Mumbai’s cancer data tells us that lung cancer is no longer just a smoker’s disease. Air pollution, occupational exposures, and genetic factors are driving cases among never smokers. This demands a shift in both public health messaging and clinical management,” he said.
According to the National Cancer Registry Programme, India recorded an estimated 1.56 million new cancer cases and 8,74,404 deaths in 2024, with lung cancer ranking among the leading causes of cancer-related mortality.
Among men, cancers of the trachea, bronchus and lungs accounted for 74,763 cases or 9.6 per cent of all cancers and 56,818 deaths or 12.3 per cent.
Among women, lung cancer contributed 30,446 cases or 3.9 per cent and 24,055 deaths or 5.8 per cent.

A 2024 review published in The Lancet Regional Health Southeast Asia found that lung cancer in India presents nearly a decade earlier than in Western countries, with a mean age ranging from 54 to 70 years.
The review also noted that 40 to 50 per cent of Indian lung cancer patients are non-smokers, a proportion that rises to 83 per cent among South Asian women. Survival outcomes remain starkly unequal, with India’s five year survival rate at 3.7 per cent, compared to 21.2 per cent in the United States and 32.9 per cent in Japan.

Mumbai’s distinct risk profile

Regional contrasts further underline Mumbai’s distinct risk profile. In the North East, especially Mizoram, lung cancer remains the leading cause of cancer mortality, driven largely by high tobacco consumption and practices such as tuibur, where tobacco smoke is infused with water.
In Mumbai, however, experts say the burden is increasingly shaped by urban air pollution and occupational exposures rather than tobacco alone.

Long term trend data spanning 25 years shows a steady rise in adenocarcinoma, with higher prevalence among women, Dr Budukh said. He noted that this subtype is more commonly seen among non-smokers, strengthening the link to environmental and genetic factors.

Projections from GLOBOCAN estimate that India’s overall cancer burden will exceed 2.2 million cases by 2040, with lung cancer continuing to rise. In Mumbai, case numbers are expected to climb sharply by 2025, with an estimated 81,219 men and 30,109 women likely to be diagnosed.

While tobacco remains a major risk factor, with 42 per cent of Indian men and 14 per cent of women consuming tobacco, studies show that in Mumbai, bidi smoking carries an even higher risk than cigarettes, with odds ratios reported as high as 18.3. Tuberculosis further complicates diagnosis and treatment. Research indicates that up to 29 per cent of lung cancer patients were initially misdiagnosed as TB, leading to delays in care. Drug interactions between TB treatment and cancer therapies also pose significant clinical challenges.

Experts at Tata Memorial Centre have called for expanded molecular testing, affordable access to targeted therapies, stricter tobacco control, and integrated tuberculosis and cancer screening programmes. Dr Budukh warned, “We need collaborative research, political will, and patient advocacy. Without these, the gap between what is possible and what is accessible will only widen.”