S-1 as adjuvant chemotherapy for stage III colon cancer: a randomized phase III study (ACTS-CC trial).

BACKGROUND: S-1 is an oral fluoropyrimidine whose antitumor effects have been demonstrated in treating various gastrointestinal cancers, including metastatic colon cancer, when administered as monotherapy or in combination chemotherapy. We conducted a randomized phase III study investigating the efficacy of S-1 as adjuvant chemotherapy for colon cancer by evaluating its noninferiority to tegafur-uracil plus leucovorin (UFT/LV). PATIENTS AND METHODS: Patients aged 20-80 years with curatively resected stage III colon cancer were randomly assigned to receive S-1 (80-120 mg/day on days 1-28 every 42 days; four courses) or UFT/LV (UFT: 300-600 mg/day and LV: 75 mg/day on days 1-28 every 35 days; five courses). The primary end point was disease-free survival (DFS) at 3 years. RESULTS: A total of 1518 patients (758 and 760 in the S-1 and UFT/LV group, respectively) were included in the full analysis set. The 3-year DFS rate was 75.5% and 72.5% in the S-1 and UFT/LV group, respectively. The stratified hazard ratio for DFS in the S-1 group compared with the UFT/LV group was 0.85 (95% confidence interval: 0.70-1.03), demonstrating the noninferiority of S-1 (noninferiority stratified log-rank test, P < 0.001). In the subgroup analysis, no significant interactions were identified between the major baseline characteristics and the treatment groups. CONCLUSION: Adjuvant chemotherapy using S-1 for stage III colon cancer was confirmed to be noninferior in DFS compared with UFT/LV. S-1 could be a new treatment option as adjuvant chemotherapy for colon cancer. CLINICALTRIALSGOV: NCT00660894.

Safety of UFT/LV and S-1 as adjuvant therapy for stage III colon cancer in phase III trial: ACTS-CC trial.

BACKGROUND: The Adjuvant Chemotherapy Trial of TS-1 for Colon Cancer (ACTS-CC) is a phase III trial designed to validate the non-inferiority of S-1 to UFT/leucovorin (LV) as postoperative adjuvant chemotherapy for stage III colon cancer. We report the results of a planned safety analysis. METHODS: Patients aged 20-80 years with curatively resected stage III colon cancer were randomly assigned to receive UFT/LV (UFT, 300 mg m(-2) per day as tegafur; LV, 75 mg per day on days 1-28, every 35 days, 5 courses) or S-1 (80, 100, or 120 mg per day on days 1-28, every 42 days, 4 courses). Treatment status and safety were evaluated. RESULTS: Of 1535 enrolled patients, a total of 1504 (756 allocated to S-1 and 748 to UFT/LV) were analysed. The completion rate of protocol treatment was 77% in the S-1 group and 73% in the UFT/LV group. The overall incidence of adverse events (AEs) were 80% in S-1 and 74% in UFT/LV. Stomatitis, anorexia, hyperpigmentation, and haematological toxicities were common in S-1, whereas increased alanine aminotransferase and aspartate aminotransferase were common in UFT/LV. The incidences of grade 3 AEs were 16% and 14%, respectively. CONCLUSION: Although AE profiles differed between the groups, feasibility of the protocol treatment was good. Both S-1 and UFT/LV could be safely used as adjuvant chemotherapy.