Lung cancer in women who have never smoked: Oncologist explains the role of air pollution, symptoms and early diagnosis

Never smoked but still at risk? Dr Sunny Jain highlights the growing concern of lung cancer among women and the factors that may contribute to it.

Lung cancer has traditionally been associated with men who smoke. However, an emerging pattern is drawing attention to another group: women who have never smoked but are increasingly being diagnosed with the disease.

In an interview with HT Lifestyle, Dr Sunny Jain, clinical director, medical onco-sciences and head of medical oncology at Marengo Asia Hospitals, Sector 16, Faridabad, explains why this changing trend calls for greater public awareness and a closer examination of environmental factors that may contribute to lung cancer.

“In clinical practice, one of the biggest misconceptions we encounter is that a person who has never smoked cannot develop lung cancer. This is simply not true. Smoking remains a major risk factor, but it is not the only one. When a woman develops a persistent cough or unexplained respiratory symptoms, the absence of a smoking history should not lead to a false sense of reassurance,” says Dr Jain, who has more than 15 years of experience in oncology.

A changing global and Indian scenario

The Indian scenario deserves particular attention as well. Data from the Indian Council of Medical Research's National Cancer Registry Programme, published in the Indian Journal of Medical Research in 2022, showed that adenocarcinoma accounted for approximately 52.7% of lung cancers among women in the hospital-based registry data analysed. The study also documented increasing lung cancer incidence in several metropolitan cities.

Research highlights lung cancer cases among women who have never smoked, with pollution-linked adenocarcinoma a significant concern

Air pollution and other risk factors

For women living in urban areas, air pollution is an important concern. Fine particulate matter, particularly PM 2.5, can penetrate deep into the respiratory tract, and prolonged exposure has been linked to lung cancer and other respiratory diseases. Vehicle emissions, industrial pollution, construction dust and the burning of solid fuels all contribute to this exposure.

According to Dr Jain, indoor air pollution is another concern that often goes unnoticed. Women exposed to smoke from biomass fuels in poorly ventilated kitchens may face additional respiratory risks. The International Agency for Research on Cancer has classified outdoor air pollution and particulate matter as carcinogenic to humans.

Research published in 2025 in JTO Clinical and Research Reports, analysing 54 studies involving approximately 16 million never-smokers, also found associations between lung cancer and non-tobacco risk factors, including passive smoking and particulate matter pollution.

Apart from air pollution, second-hand tobacco smoke, radon, occupational exposure to carcinogens such as asbestos and arsenic, family history and genetic susceptibility can contribute to lung cancer risk.

“In many patients, it is difficult to identify one specific cause. Lung cancer can develop through a combination of environmental, biological and genetic factors, and sometimes the precise cause remains unknown,” explains Dr Jain.

Why diagnosis may be delayed

According to him, one of the major challenges is that symptoms in women who have never smoked may initially be attributed to seasonal pollution, allergies, asthma or recurrent respiratory infections. This can sometimes delay further investigation.

Dr Jain emphasises that persistent respiratory symptoms should not be ignored, irrespective of a person's smoking history.

“A cough that persists for several weeks, unexplained weight loss, coughing up blood, progressive breathlessness or repeated chest infections should not be ignored. These symptoms do not necessarily mean cancer, but they warrant medical evaluation, especially when they persist or worsen despite treatment,” he says.

Different lung cancer subtypes may require different treatments, making histopathological examination and molecular testing important.

Early diagnosis and personalised treatment

As Dr Jain points out, lung cancer is not a single disease, and different subtypes may require different treatment approaches. Histopathological examination and molecular testing play an important role in determining the most appropriate treatment.

Alterations such as EGFR mutations and ALK rearrangements are particularly relevant in certain lung adenocarcinomas and may make patients eligible for targeted therapies. Depending on the disease stage, tumour characteristics and the patient's overall health, treatment may include surgery, radiotherapy, chemotherapy, immunotherapy or targeted therapy.

“Advances in molecular testing and targeted therapies have significantly expanded treatment options for patients with lung cancer. Identifying the specific characteristics of a tumour can help doctors select the most appropriate treatment for an individual patient,” says Dr Jain.

He also cautions against unnecessary screening. Routine low-dose CT screening is not currently recommended for every asymptomatic woman who has never smoked. Screening should follow established eligibility criteria and individual risk assessment. However, people experiencing persistent symptoms should undergo appropriate medical evaluation without delay.

The need for greater awareness

According to Dr Jain, reducing lung cancer risk requires collective efforts, including cleaner household fuels, better kitchen ventilation, improved outdoor air quality, occupational safety measures and protection from second-hand smoke.

He believes public awareness must also challenge the misconception that lung cancer is exclusively a smoker's disease.

“The message is straightforward: lung cancer in women who have never smoked deserves greater recognition. A history of never smoking does not eliminate the possibility of cancer. Recognising the risk, investigating persistent symptoms and ensuring timely access to appropriate diagnosis can make a meaningful difference to patient care,” concludes Dr Jain.

Greater awareness, timely medical consultation and advances in personalised treatment can help improve the diagnosis and management of lung cancer among women, including those who have never smoked.

Note to readers: This article is for informational purposes only and not a substitute for professional medical advice. Always seek the advice of your doctor with any questions about a medical condition.