Efficacy of Ninjin'yoeito in Adjuvant Chemotherapy for Colorectal Cancer: A Retrospective Clinical Study with...

Adjuvant chemotherapy (AC) is the standard treatment for stage III colorectal cancer (CRC). However, its effectiveness is limited owing to adverse effects, particularly chemotherapy-induced peripheral neuropathy (CIPN). The objective of this study was to evaluate the real-world efficacy of Ninjin'yoeito (NYT), a traditional Kampo medicine, in improving chemotherapy tolerance and reducing adverse effects during AC with capecitabine plus oxaliplatin (CAPOX).

Fifty-eight patients undergoing AC with CAPOX for CRC were retrospectively analyzed. The patients were divided into two groups: those who received NYT (N group) and those who did not receive NYT (C group). Propensity score matching (PSM) was performed to minimize baseline differences. Outcomes, including appetite loss, fatigue, CIPN, and relative dose intensity (RDI), were compared between the groups.

According to the post-matching analysis, the N group demonstrated significant reductions in appetite loss (Grade ≥1:16 vs. 10; p = 0.03), fatigue (Grade ≥1:17 vs. 12; p = 0.04), and CIPN (Grade ≥1:14 vs. 7; p = 0.02). In addition, the N group exhibited significantly higher RDI for capecitabine (93.6% vs. 73.5%; p = 0.002) and oxaliplatin (83.5% vs. 55.8%; p < 0.001). No NYT-related adverse events were observed.

NYT could improve AC outcomes by reducing adverse effects and supporting a higher RDI, particularly in patients with frailty.