Risk of overall and site-specific cancers in Behçet disease: A nationwide population-based study in Taiwan

Objective. The relationship between autoimmune disease and cancer is complex while large-scale epidemiological studies of cancer risk in Behçet disease (BD) have not been reported. Therefore, we conducted a nationwide population-based cohort study. Methods. By using the National Health Insurance Research Database of 23 million people in Taiwan, we identified 1314 new patients with BD without previous cancer from 2000-2009 as a cohort. Standardized incidence ratios (SIR) of overall and site-specific cancers in patients with BD in comparison with the general population were calculated from 2000-2011. Results. Among the 1314 patients with BD, 30 developed cancers (9 men and 21 women). In overall cancer risk analysis, patients with BD had a higher risk (SIR 1.5, 95% CI 1.03-2.11). Among them, female patients with BD (SIR 1.8, 95% CI 1.14-2.7), but not male patients with BD (SIR 1.08, 95% CI 0.53-1.98), have a higher risk of overall cancer. In site-specific cancer risk analysis, patients with BD had a higher risk of non-Hodgkin lymphoma (SIR 8.3, 95% CI 2.1-22.7), hematological malignancy (SIR 4.2, 95% CI 1.3-10.2), and female breast cancer (SIR 2.2, 95% CI 1.004-4.1). The cancer risk was highest within the first-year followup (SIR 2.7, 95% CI 1.3-5.1), with 75% of the hematological malignancies found within the first year. Conclusion. This nationwide cohort study of cancer risk in patients with BD provides important information about the relationship between BD and malignancies. The results can be useful for cancer surveys in the future.