Lung Cancer No More Smokers' Disease: Experts Reveal How Everyone Is Affected, Even Children

August 1 is annually observed as World Lung Cancer Day to raise awareness about the type of cancer that originates in the lungs and spreads to other parts of the body. Smoking is one of the primary causes of lung cancer, but alarming trends suggest that lung cancer can "no longer be seen as a smoker's disease" as it is affecting men, women and even children who don't smoke.

"While smoking remains the leading cause, globally and in India, a concerning number of patients diagnosed today have never smoked a cigarette, and it's on the rise," Dr Srivatsa Lokeshwaran, Lead Consultant and Head of Department - Interventional Pulmonology and Lung Transplant, Aster Whitefield Hospital, Bengaluru, told NDTV.

This growing trend is supported by Indian studies and global data that suggests a change being driven by environmental, occupational and/or genetic risk factors.

A Lancet study, published in 2022, found that long-term exposure to fine particulate matter (PM2.5) caused an increase in the incidence rate of non-small cell lung cancer in non-smokers in urban and industrialised regions.

In most Indian cities like Delhi, Bengaluru, and Kanpur, pollution levels have become too high to be considered acceptable by the World Health Organization (WHO).

Air pollution would not merely irritate lung tissues; it can also damage DNA, thus, potentially creating cancer by the chronic exposure to pollutants such as soot, nitrogen dioxide, and benzene.

Are Children At Risk? Can They Get Lung Cancer Or Other Severe Lung Diseases?

Dr Shishir Bhatnagar, Senior Consultant - Paediatrician and Neonatologist at Cloudnine Group of Hospitals, Noida, told NDTV that lung cancer as such in children is "not very common". The cancers in the lungs are basically carcinoids, adenocarcinomas and subtle pleuropulmonary blastomas. Most of these cancers may have their origin rarely from smoking and genetic factors.

"More commonly in children, the lungs are affected by inflammation and infections. The inflammations are basically contributory and they are responsible for creating conditions like asthma and bronchitis," Dr Bhatnagar said.

"Infections like bronchopneumonias, bronchitis, bacterial bronchitis and bronchiolitis are also contributed to by the environmental factors, including smoking and environmental smoke and dust."

The smoking at the microbiological level can affect the immune system and weaken it by affecting the annular macrophage system. It also disturbs the microbiome of the airways, thereby increasing the biological injuries in them. At the cellular level, it affects the DNA and makes it more prone to inflammation and cancer.

According to Dr Bhatnagar,  the bigger issue is the serious lung harm from environmental exposures during early childhood. Children who live in high pollution neighbourhoods, and/or have been exposed to passive smoke, unclean fuels, or multiple respiratory infections as infants, potentially have sustained damage to their lungs, some of which may lead to chronic disease (bronchiectasis, asthma, lung cancer) in the future.

A study published in 2023 in The New England Journal of Medicine demonstrated that children exposed to high levels of PM2.5, impaired lung function, asymmetrically slowed lung development, and had the potential for life-long impairment related to lung function.

Serious Concerns Over Vaping

Experts are also concerned about the rising trend of vaping. Dr Bhatnagar said that vaping is some sort of mechanism where the toxins produced are less and are not equivalent to smoking. "The toxins are less, but they have high nicotine dependence. There are very high chances that in adolescence this can become a trouble, and it is actually a problem these days," he said, further adding that vaping can contribute and can actually go on to smoking.

"Children may not have early symptoms of cancer, but a persistent cough, wheezing without being diagnosed with asthma, recurrence of pneumonia, or even chest pain of unknown origin, must be taken seriously," Dr Bhatnagar said.

Children must be protected from indoor air pollution, and also reduce exposure to passive smoke, while treating infections early, as lung health is often forgotten.

Major Causes Of Lung Cancer

The most frequent cause is smoking, responsible for more than 70 per cent of cases and 90 per cent of diagnoses. "Tobacco smoke harbours more than 60 carcinogens, and the risk is directly proportional to the intensity of smoking. The world's second-largest consumer of tobacco is India, which has 267 million consumers of tobacco, and tobacco is responsible for 27% of all cancers," Dr Vinayak Maka, Consultant - Dept of Medical Oncology, Ramaiah Institute of Oncosciences, Ramaiah Memorial Hospital, told NDTV.

For all causes except tobacco, environmental and occupational risk factors are important:

• Passive Smoking: Significantly boosts risk.
• Radon Gas: The Second greatest risk factor after smoking, particularly in smokers.
• Occupational Exposure: Chemicals like asbestos, arsenic, and beryllium raise risk, especially among smokers.
• Genetic Influence: Family health history is one of the major contributing factors in making a person more vulnerable.
• Air Pollution: A high-risk factor; Delhi alone has witnessed an increase in lung cancer cases due to pollution.
• Diet and Processed Foods: Studies have found that an intake of ultra-processed foods leads to a 41 per cent higher risk, undermining the role played by diet.

Regular Screening And Early Detection

Dr Raja Dhar, Director & HOD - Pulmonology,  CMRI Kolkata, weighed in on the strength of regular screening and early detection. He told NDTV, "Regular screening is also key, particularly for those at greater risk, because it enables us to catch problems early on, when treatment works best. Lung cancer too often gets diagnosed too late, but if we can detect it early, the likelihood of successful treatment is greatly enhanced."