Reduction in the Incidence of Urological Cancers after the Ban on Chinese Herbal Products Containing Aristolochic Acid: An Interrupted Time-Series Analysis

Cancer is a public health problem worldwide. Taiwan has a higher incidence rate of urological cancers than many Asian countries do. Aristolochic acid has been considered a potent carcinogen. In this study, we examined whether the cessation of the sales and preparation of aristolochic acid-containing Chinese herbal products (AA-CHPs) in Taiwan contributed to a decline in the incidence rates of bladder cancer, carcinomas of the renal pelvis and other urinary organs, and kidney cancer. We conducted an interrupted time-series analysis of long-term trends in the incidence rates of the aforementioned cancers between 1995 and 2013 in Taiwan. The incidence rates of bladder cancer and carcinomas of the renal pelvis and other urinary organs decreased considerably after 2008 and 2011, respectively. Notably, these change-of-slope time points occurred after the year 2003, when a ban on AA-CHPs was imposed in Taiwan. The ban on AA-CHPs in Taiwan was possibly associated with the reduction in the incidence of bladder cancer and carcinomas of the renal pelvis and other urinary organs.