A retrospective integrated-health-system cohort compared 2,332 IBD patients receiving anti-TNF alone with 549 receiving anti-TNF plus methotrexate over a mean 3.3 years. Cancer incidence was 6.4 versus 7.4 per 1,000 person-years and adjusted HR 0.94. No difference was detected, but the 95% CI of 0.47-1.89 still permits clinically important benefit or harm.
Key findings
- There were 2,332 monotherapy and 549 combination patients; mean age was 35, 75.8% had Crohn's and mean follow-up was 3.3 years, totalling 8,031 and 1,353 person-years. Cancer incidence was 6.4 versus 7.4/1,000 person-years (p=0.64). Adjusted HRs were 0.94 (0.47-1.89) overall, 0.57 (0.07-4.51) for skin and 1.00 (0.48-2.11) for non-skin cancer. Age at least 60 and prior thiopurine exposure predicted higher risk.
Why this matters globally
The study narrows uncertainty when balancing combination efficacy against cancer concern and supports shared decisions incorporating age, thiopurine history and individual risk.
Thai researcher contribution
Wasuwit Wanchaitanawong is affiliated with Chiang Mai University's gastroenterology division and Massachusetts General Hospital. The cohort comes from an overseas healthcare system, not a Thai patient registry.
Limitations to consider
Observational design permits confounding by indication and time-varying exposure. Combination person-time was smaller, confidence intervals were wide, especially for skin cancer, and 3.3 years may be short for some malignancies. A null result is not equivalence or a safety guarantee.
Verify the original sources
Inflammatory Bowel DiseasesRead the original article↗DOI: 10.1093/ibd/izag143