Suma Prakash had never smoked a day in her life. A 54-year-old schoolteacher from Kochi, she had breathed the city’s traffic-clogged air for three decades. When a persistent cough began in the winter of 2022, her doctor reassured her — non-smokers rarely get lung cancer. By the time a scan found the tumour, it had already spread to her lymph nodes. Stage IIIB. The window for a cure had quietly closed.
Her story is heartbreakingly common. Roughly a quarter of lung cancer patients have never smoked, yet screening programmes remain built almost entirely around smokers aged 50-70, leaving people like Suma outside the net entirely.
The scale of the problem is stark. “Almost 80% of patients are diagnosed with stage IV cancers,” says Dr Arun R Warrier, senior consultant – medical oncology, Aster Medcity, Kochi. Early tumours rarely cause symptoms, he explains, and are usually caught only by chance, during an unrelated scan or X-ray. “We see patients who come with 8-10 cm tumours that developed over weeks to months,” he says — by which point only palliative, not curative, treatment remains possible.
This silence in the early, treatable years is what has made lung cancer the world’s deadliest cancer for decades: doctors fighting fires they can only see once they’re already blazing.
Now a study in the journal ‘Cell’ offers a way to spot the fire before the smoke. Researchers at the Francis Crick Institute and UCL, co-led by Dr Clare Weeden, analysed blood plasma from more than 48,000 UK Biobank participants and identified a 14-protein signature that can flag lung cancer risk more than five years before diagnosis. The signal doesn’t come from a tumour itself. It reflects chronic inflammation in the lungs, driven partly by air pollution, that wakes up dormant mutated cells and creates fertile ground for cancer to take hold.
The team validated the signature across eight global datasets, including non-smokers, finding it elevated in every group that later developed the disease.
The finding lends weight to ideas long suspected but not proven. “It’s definitely an early signal — and it does prove an underlying assumption,” says Dr Aju Mathew, consultant oncologist at MOSC Medical College, Kolenchery, noting that it strengthens the case that curbing interleukin-1-related inflammation lowers lung cancer risk, and that pollution itself drives the disease.
That link may already be actionable. Blocking interleukin-1 beta reduced early tumour growth in animal models, and in a reanalysis of a major cardiovascular trial of 4,651 patients, those with a high baseline signature who received the IL-1B blocker canakinumab saw their lung cancer risk nearly halved — hinting the test could eventually guide prevention, not just detection.
But clinicians caution against confusing this with screening. “It is not equivalent to screening. Standard screening involves annual low-dose CT,” says Dr P S Shajahan, professor and head of pulmonary medicine, Government Medical College, Kollam. That screening remains reserved for defined high-risk groups, chiefly current or former heavy smokers aged 50-80. The new test, he stresses, “is neither diagnostic nor predictive of lung cancer” on its own, though it may help flag people at risk for genetic reasons that current criteria miss.
The path from lab to clinic is still long. “These tests are still in an early, experimental stage, but we do hope they become recommended in the near future. For this, further validation studies are needed,” Dr Warrier says.
Until then, the Sumas of the world must rely on vigilance and whatever screening tools exist. But somewhere in a laboratory, the blueprint for their protection already exists — written in 14 proteins, waiting in blood.
Spot the fire before the smoke
A study in the journal Cell offers a way to spot the fire before the smoke. Researchers at the Francis Crick Institute and UCL, co-led by Dr Clare Weeden, analysed blood plasma from more than 48,000 UK Biobank participants and identified a 14-protein signature that can flag lung cancer risk more than five years before diagnosis. The signal doesn’t come from a tumour itself. It reflects chronic inflammation in the lungs, driven partly by air pollution, that wakes up dormant mutated cells and creates fertile ground for cancer to take hold.
