Scientists highlight unique lung cancer traits in Southeast Asia, call for region-centric research

New Delhi: Lung cancer in Southeast Asia is "very different in myriad aspects" from that in other parts of Asia and the West, highlighting an urgent need for research in the region, scientists have pointed out.

The researchers also found that the genetic makeup of lung cancer in India is "shaped by the intricate diversity of its people."

They have also found that a "substantial proportion" of lung cancer patients in India never smoked and air pollution can cause lung cancer even in non-smokers.

The scientists called for region-centric studies regarding how specific climate variables, such as air pollution and other environmental cancer-causing agents, directly contribute to lung cancer.

Compared to the rest of the world, the India-to-world ratio in terms of lung cancer research produced is 0.51, a team of researchers, including those from Tata Memorial Hospital, Mumbai said.

The authors, in the research series published in The Lancet's eClinical Medicine journal, reviewed available data generated in Southeast Asia to better understand the profile of lung cancer in the region, with a focus on India. They found that a "substantial proportion" of lung cancer patients never smoked.

The team studied lung cancer-related mutations and found that EGFR and ALK were reported to be 30 per cent and 10 per cent prevalent, respectively. EGFR is associated with little to no smoking history.

"Although several guidelines exist, we require a set of dynamic guidelines which change with changing science, and are region-centric, which are developed from data generated in Southeast Asia rather than based on global data," the authors wrote.

In another paper from the series, researchers, including those from the All India Institute of Medical Sciences (AIIMS), New Delhi, found that air pollution can cause lung cancer even in non-smokers. They analysed the impact of climate change on lung cancer in Asia.

South Asia is home to 37 of the 40 most polluted cities in the world, and India is among the four most polluted countries, the authors said, quoting the World Air Quality Report in 2022.

Climate change is known to raise the likelihood of extreme weather events, including floods, storms and heatwaves.

These events can damage critical infrastructure, disrupt healthcare systems, and potentially expose an increasing number of people to cancer-causing agents in the environment, the authors said.

There were 81 weather, climate and water-related disasters in 2022. With over 83 per cent flood and storm events, more than 50 million people were directly affected, they said, quoting the State of the Climate in Asia Report by the World Meteorological Organization (WMO).

China, India, Indonesia, Philippines and Thailand have been the worst hit by natural disasters in Asia, and these countries had the highest lung cancer cases in 2020 with over 9.65 lakh new cases, the researchers said.

According to WMO's State of the Climate in Asia Report 2023, Asia "remained" the world's worst-hit region in terms of experiencing extreme weather events.

"As climate change continues to unfold, it magnifies the burden of lung cancer which is already a significant public health challenge in Asia," the authors wrote.

They called for studies regarding how specific climate variables, such as air pollution and other environmental cancer-causing agents, directly contribute to lung cancer.