The review searched three databases to June 2026 for evidence that e-cigarettes, snus and other alternative nicotine products alter response to chemotherapy, cancer progression or cancer-related death. No epidemiological study addressed the question; some observational evidence associates snus with higher cancer-related mortality, while an in vitro report of e-cigarette-induced cisplatin resistance in head and neck squamous cell lines was not confirmed on multi-centre replication. The authors conclude the evidence base cannot support a determination either way.
Why it is interesting: Marks an evidence gap rather than a finding: nicotine substitution among cancer patients is unmeasured at population scale.