Background: A combination of 5-fluorouracil/folinic acid plus oxaliplatin (FOLFOX) is a standard regimen for the chemotherapy of metastatic colorectal cancer. The major dose-limiting toxic effect of oxaliplatin is neurotoxicity. The aim of this study was to evaluate the preventive effects of traditional Japanese medicines, goshajinkigan and shakuyakukanzoto on oxaliplatin-induced neurotoxicity with FOLFOX.
Patients and methods: Between July 2006 and November 2008, a total of 44 patients with metastatic colorectal cancer received modified FOLFOX6 or FOLFOX4, as first-line chemotherapy at three institutions. They concurrently received either goshajinkigan (group A, n=20) or shakuyakukanzoto (group B, n=24) for neurotoxicity reduction.
Results: The median number of treatment cycles and the median cumulative dose of oxaliplatin were 12 cycles (range, 4-19) and 898 mg/m(2) (range, 340-1255) in group A and 10.5 cycles (range, 6-20) and 845 mg/m(2) (range, 510-1480) in group B. Eighteen patients in group A and 24 in group B received oxaliplatin in a cumulative dose exceeding 500 mg/m(2). At a dose of 500 mg/m(2) oxaliplatin, grade 1-2 toxicity occurred in 10 patients of group A and in 7 of group B, but there was no grade 3 or higher toxicity in either group. The response rate of the 38 patients with measurable lesions was 50.0% (9/18) in group A and 65% (13/20) in group B.
Conclusion: The administration of traditional Japanese medicine may reduce oxalipatin-induced neurotoxicity without negatively affecting tumor response in patients with colorectal cancer who undergo FOLFOX therapy.