Lung cancer has the highest rate of disability-adjusted life years of all cancers in India. Traditionally considered a male-dominant, smoking-related disease, it is now increasingly seen in women particularly non-smokers, challenging long-held assumptions. This trend highlights the growing role of non-tobacco risk factors such as indoor air pollution, radon, arsenic exposure, particulate matter, and chronic airway inflammation.

Epidemiological studies show a higher proportion of lung cancer cases in non-smokers in East Asia, with about one-third of patients being non-smokers. Indian women carry distinct genetic vulnerabilities. Variants in the CYP1A1, GSTM1, and GSTT1 genes enzymes responsible for carcinogen detoxification are highly prevalent in South Asian populations, impairing the body’s ability to neutralize inhaled toxins. Non-smoking women are more than twice as likely to develop lung cancer compared to male non-smokers.

A recent study from Karnataka has revealed a concerning shift in lung cancer trends. Researchers followed 89 women under the age of 50—none of whom had ever smoked or lived in smoking households—over a five-year period. Most patients presented with a simple but persistent symptom: a dry cough lasting around three months. Yet, nearly 70% were diagnosed at an advanced stage (stage IV). Majority of these women had prolonged exposure to poorly ventilated cooking environments. Repeated heating of cooking oil generates carcinogens such as polycyclic aromatic hydrocarbons and reactive aldehydes, which induce oxidative DNA damage and promote mutations, particularly in the EGFR gene which contributes to EGFR mutations that is commonly seen in up to 40–50% of Indian non-smoker lung adenocarcinoma cases, far higher than in Western populations. Detection of this mutation on novel testing platforms has revolutionized Lung cancer treatment from mere months to several years of survival with excellent quality of life.

Emerging risks further compound the burden. Despite regulatory bans, e-cigarette use is rising, exposing individuals to toxic aerosols. Particularly among younger urban women who perceive them as “safe.” The aerosol contains formaldehyde, diacetyl, heavy metals, and ultrafine particles capable of causing oxidative stress and DNA damage. Additionally, India’s severe air pollution with widespread exposure to PM2.5, nitrogen dioxide, and vehicular exhaust significantly elevates lung cancer risk even without tobacco use.

We routinely recommend annual low-dose CT (LDCT) screening for high-risk non-smoking Indian women aged 40–74 with prolonged daily indoor cooking with exposures of more than 10 years, poorly ventilated kitchens, a first-degree family history of lung cancer, residence in high-pollution zones of AQI >150, chronic exposure >5 years, or a confirmed EGFR/ALK mutation in family members.

The biggest takeaway is simple but critical:  

• A dry cough lasting more than 2–3 weeks  
• Unexplained chest pain  
• Breathlessness  
• Unusual fatigue or weight loss of >10% over 6 months 

“Your lungs matter—listen when they speak.”