Doctors at one of Delhi’s largest private hospitals say they are now diagnosing gastrointestinal (GI) cancers in patients as young as 15, and want researchers to look much more closely at whether the capital’s polluted air is part of the reason. The concern was raised at a two-day international conference on colorectal and other GI cancers, held on October 10 and 11 by Sir Ganga Ram Hospital together with The Christie NHS Foundation Trust in the UK.
Younger patients in the clinic
Dr Shyam Aggarwal, who chairs medical oncology at the hospital and is organising chairperson of the conference, said cases like these were rare only a few years ago.
In our OPD we are now seeing new GI cancer patients as young as 15, which was uncommon five years ago.
Dr Shyam Aggarwal, Sir Ganga Ram Hospital
Dr Saumitra Rawat, who heads surgical gastroenterology and GI and HPB onco-surgery at the hospital, said younger patients should be assessed for several possible contributors at once: family history, genetic susceptibility, diet, lifestyle, infections and environmental exposures. Hospital-based studies in India have also reported younger people being diagnosed when their disease is already at an advanced stage.
What the evidence says so far
Speakers pointed to a growing body of international research. A 2026 review of 70 studies on air pollution and digestive diseases found that long-term exposure to fine particulate matter, or PM2.5, was associated with higher death rates from GI cancers, with a notable link to colorectal cancer. A separate study published in Nature Health examined how long-term exposure to PM2.5, nitrogen dioxide and ozone relates to overall cancer risk.
Experts were careful to stress that these findings show associations, not proof that pollutants directly cause GI cancers. Established risk factors such as diet, lifestyle and genes remain central to the picture.
Why India needs its own data
The Indian numbers are still lower than in some Western countries but are moving in a worrying direction. One analysis comparing England and India put England’s early-onset colorectal cancer rate at 8.4 per lakh people under 50 in 2023, against 3.5 per lakh among Indians aged 25 to 49. Urban cancer registries in India have shown a steady rise in colorectal cancer.
Doctors at the meeting argued that India needs its own long-term research on the question, rather than relying only on findings from other countries.
What experts want next
The conference called for:
- stronger air-quality monitoring
- better and more complete cancer registries
- long-term Indian studies tracking pollution exposure against patients’ clinical outcomes
For the public, doctors urged anyone with persistent digestive symptoms to see a doctor promptly rather than wait, and stressed the value of screening, early diagnosis and standard cancer-prevention measures. The discussion comes as Delhi heads into the colder months, when its air quality usually worsens.
