Singapore faces a puzzling public health challenge: despite having among the world's lowest smoking rates and strongest tobacco control measures, 48 percent of local lung cancer patients are people who have never smoked – more than double the rate in Western nations.
The statistic, highlighted by oncologists in a new report on lifestyle-driven cancer risks, points to a regional phenomenon that is reshaping how Southeast Asian health authorities think about lung cancer screening and prevention.
Dr. Chan, an oncologist quoted in The Straits Times, noted that Singapore's tobacco control measures – including one of the world's highest tobacco taxes, recently hiked by 20 percent – have successfully reduced smoking rates to among the lowest in the region. Those measures have in turn helped reduce tobacco-related lung cancer rates.
But the emergence of lung cancers in non-smokers has become an area of growing concern. "This is particularly prevalent among Asian women, driven by specific genetic alterations, most commonly the epidermal growth factor receptor gene," Dr. Chan said.
Mutations in the EGFR gene have been linked to lung cancer and are significantly more prevalent in Asian populations than in European or American populations. Among Western nations, non-smokers account for only 10 to 20 percent of lung cancer cases, making Singapore's 48 percent rate particularly striking.
The genetic difference has profound implications for public health policy. Singapore's current guidelines recommend lung cancer screening for people aged 50 to 80 with at least a 20-pack-year smoking history who still smoke or quit within the past 15 years. But those criteria miss nearly half of Singapore's lung cancer patients – those who never smoked.
