Higher Risk for Hematological Malignancies in Inflammatory Bowel Disease: A Nationwide Population-based Study in Taiwan.

OBJECTIVES

The relationship between inflammatory bowel disease (IBD) and cancer remains unclear especially in Asian populations. Therefore, we conducted a nationwide population-based study in Taiwan to reveal the cancer risk in patients with IBD.

METHODS

Using the national health database of Taiwan, we identified 3,348 IBD patients without previous cancer, including 685 with Crohn's disease (CD) and 2,663 with ulcerative colitis (UC), as a cohort from 1998 to 2012 and followed them up until 2013. Standardized incidence ratios (SIRs) of overall and site-specific cancers in CD and UC patients in comparison with the general population were analyzed.

RESULTS

Regarding overall cancer risk analysis, both CD (SIR 1.4, 95% confidence interval (CI) 0.9-2.1) and UC (SIR 0.93, 95% CI 0.7-1.1) patients did not have a higher risk. In site-specific cancer risk analysis, CD (SIR 14.08, P<0.01) and UC (SIR 2.51, P=0.02) patients had a higher risk of hematological malignancies. The risk of colorectal cancer (CRC) did not increase significantly in either CD (SIR 0.96, P=0.7) or UC (SIR 1.39, P=0.22) patients.

CONCLUSIONS

This first nationwide population-based study in Asia reveals a significantly higher risk for hematological malignancies in IBD patients. This finding may highlight the importance of screening for hematological malignancies in patients with IBD in the future.