Background: Based on its potent inhibition of dihydropyrimidine dehydrogenase (DPD), S-1 is expected to be more active than other flouropyrimidines against tumors with higher DPD activity, such as hepatocellular carcinoma (HCC).
Patients and methods: We retrospectively investigated the efficacy of S-1 and platinum in HCC. Patients received S-1 (80 mg/m(2)/day on days 1-14) with either cisplatin (60 mg/m(2) on day 1) or oxaliplatin (130 mg/m(2) on day 1) every 3 weeks. The primary end point was overall response rate.
Results: Among the 21 HCC patients, 12 and 9 patients received S-1-based chemotherapy as a first-line and salvage treatment, respectively. Partial response was seen in 5 patients and stable disease in 6. The median time-to-progression was 4.0 months (95% confidence interval [CI], 2.4-5.6) and median overall survival was 14.0 months (95% CI, 6.7-21.3). Most patients were tolerable to chemotherapy and no grade 4 toxicity was observed. Tumors with lower DPD expression were more responsive to the therapy (response rate 60.0% in lower vs. 0.0% in higher DPD, p=0.045).
Conclusion: S-1 and platinum combination chemotherapy shows favorable efficacy and tolerability in advanced HCC.