Optimal dose of silymarin for the management of drug‑induced liver injury in oncology.

Systemic oncological treatment may cause drug-induced liver injury (DILI). Therefore, there is a pressing need for an active drug able to accelerate liver regeneration. Silymarin mitigates oxidative stress, and inhibits pro-inflammatory and pro-apoptotic cytokines and the fibrotic transformation of liver tissue. Currently, there are a lack of data regarding the optimal dosage of silymarin and its efficacy. Thus, the present retrospective study aimed to determine the optimal dose of silymarin for use in oncological DILI treatment. For this purpose, 180 patients with solid malignancies treated with systemic oncological therapy and silymarin between January, 2015 and November, 2021 were enrolled in the study. Alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total bilirubin (Bil) levels, as well as the dose of silymarin were assessed at the initiation of silymarin treatment, after 3-6 weeks and after 6-12 weeks. Pearson's correlation analysis was performed to evaluate the correlation between the initial dose of silymarin (IDoS), and the ALT, AST and Bil levels. The effects of four independent variables, namely IDoS, the initial dose reduction of systemic treatment, the systemic treatment dose reduction at first assessment (DR1M) and the elevation of the silymarin dose at first control on the ALT, AST and Bil levels were evaluated using regression analysis. The median IDoS was 450 mg. A decrease in or the stabilization of the ALT, AST and Bil levels after 6-12 weeks were observed in 68.63, 65.85 and 53.25% of patients, respectively. There was a weak correlation between IDoS and the decrease in ALT and AST levels after 6-12 weeks (correlation coefficient, R=0.361 and 0.277 respectively, P<0.001). No significant correlation between the IDoS and a decrease in Bil levels was observed. DR1M was a negative predictor for a decrease in Bil levels in patients with liver tumors. On the whole, the present study demonstrates that silymarin appears to be efficient in alleviating DILI at a dose of 300-450 mg. A further increase in the dose of silymarin may not lead to an adequate increase in its efficacy.