We conducted a National Health Insurance Research Database-based Taiwanese nationwide population-based cohort study to evaluate whether Chinese herbal medicine (CHM) treatment decreased the incidence of
chronic hepatitis in
breast cancer patients receiving
chemotherapy and/or
radiotherapy. A total of 81171 patients were diagnosed with
breast cancer within the defined study period. After randomly equal matching, data from 13856 patients were analyzed. Hazard ratios of incidence rate of
chronic hepatitis were used to determine the influence and therapeutic potential of CHM in patients with
breast cancer. The patients with
breast cancer receiving CHM treatment exhibited a significantly decreased incidence rate of
chronic hepatitis even across the stratification of age, CCI score, and treatments. The cumulative incidence of
chronic hepatitis for a period of seven years after initial
breast cancer diagnosis was also reduced in the patients receiving CHM treatment. The ten most commonly used single herbs and formulas were effective in protecting liver function in patients with
breast cancer, where Hedyotis diffusa and
Jia-Wei-Xiao-Yao-San were the most commonly used herbal agents. In conclusion, our study provided information that western medicine
therapy combined with CHM as an adjuvant modality may have a significant impact on liver protection in patients with
breast cancer.