Phase II study of oxaliplatin combined with S-1 and leucovorin (SOL) for Chinese patients with metastatic colorectal cancer

BACKGROUND: Fluoropyrimidine and oxaliplatin are widely used for patients with colorectal cancer. This phase II study was conducted to evaluate the efficacy and safety of the combination of S-1, oxaliplatin, and leucovorin (SOL) in the treatment of Chinese patients with metastatic colorectal cancer (mCRC). METHODS: Eligible patients with untreated mCRC from four hospitals in China received intravenous oxaliplatin (85 mg/m(2)) on day 1, oral S-1 twice daily (80–120 mg per day) on day 1–7, and leucovorin twice daily (50 mg per day) simultaneously with S-1, every 2 weeks. RESULTS AND DISCUSSION: Forty patients were enrolled in our study. In total, 296 cycles of SOL were administered. The overall response rate was 50.0%. At a median follow-up of 27 months, progression-free survival and overall survival were 7.0 months (95% confidence interval [CI] 6.0–10.6 months) and 22.2 months (95% CI 15.1–29.3 months), respectively. The most common grade 3/4 non-hematological adverse events were diarrhea (n = 8, 20.0%), nausea (n = 3, 7.5%), and vomiting (n = 3, 7.5%). The most common grade 3/4 hematological toxicities were thrombocytopenia (n = 3, 7.5%), neutropenia (n = 1, 2.5%), and abnormal alanine transaminase/aspartate transaminase levels (n = 1, 2.5%). There was one treatment-related death. CONCLUSIONS: The data indicate that the SOL regimen is effective and moderately tolerated in Chinese patients with mCRC. Trial registration: Clinical trial information: ChiCTR-TNRC-100000838