Efficacy and safety of modified Xiaoyao-san in the treatment of postoperative depression of breast cancer: a systematic review and meta-analysis.

OBJECTIVE: To comprehensively evaluate the efficacy and safety of modified Xiaoyao-san (XYS) in the treatment of postoperative depression of breast cancer patients through systematic review and meta-analysis. METHODS: Randomized controlled trials (RCTs) on the treatment of postoperative depression of breast cancer patients with modified XYS were searched from eight databases. All relevant literature from the inception of each database up to 12 July 2026 were retrieved. The Cochrane risk of bias assessment tool was used to evaluate the risk of bias in all included studies. After screening and data extraction, RevMan 5.2 and Stata 12.0 were used for meta-analysis. RESULTS: 11 RCTs were included, involving a total of 748 patients, with 374 in the treatment group and 374 in the control group. Subgroup analyses showed that modified XYS plus antidepressants (AD) was associated with a significantly greater improvement in depressive symptoms than AD alone [SMD = -0.99, 95% CI (-1.57, -0.42), p = 0.001], whereas modified XYS alone did not significantly improve depressive symptoms compared with the control group [SMD = 0.07, 95% CI (-0.08, 0.23), p = 0.358]. In addition, both modified XYS plus AD and modified XYS alone significantly increased 5-HT, DA, and NE levels (p < 0.05). CONCLUSION: This study indicates that modified XYS has a positive effect on the improvement of depression scale scores, neurotransmitters in patients with postoperative depression of breast cancer. However, further verification is needed through more high-quality RCTs. SYSTEMATIC REVIEW REGISTRATION: https://www.crd.york.ac.uk/prospero, identifier CRD420251035045.