Adjuvant Therapy with Oral Fluoropyrimidines as Main Chemotherapeutic Agents After Curative Resection for Colorectal Cancer: Individual Patient Data Meta-analysis of Randomized Trials

BACKGROUND: Oral 5-fluorouracil and its prodrugs (tegafur, carmofur) is now being studied for adjuvant chemotherapy of curatively resected colorectal cancers. To evaluate the effect of these oral fluoropyrimidines (o-FPs), an individual patient data (IPD) meta-analysis of randomized clinical trials was performed in Japan as an inter-trialist group study. METHODS: Data from the three clinical trials in which postoperative adjuvant therapy with o-FPs was compared with surgery alone in patients with colorectal cancer were sought. IPD from a total of 4960 patients with follow-up periods of at least 5 years were analyzed. RESULTS: The results of the meta-analysis on an 'intention to treat' basis demonstrated a significant benefit of o-FPs in terms of the disease-free survival (DFS) of the total patients [risk ratio (RR) 0.830, 95% confidence interval (CI) 0.742-0.929, P = 0.001]. o-FPs were also demonstrated to be effective for survival in rectal cancer (RR 0.857, 95% CI 0.734-0.999, P = 0.049) and in Dukes'C colorectal cancer (RR 0.828, 95% CI 0.711-0.965, P = 0.016). CONCLUSION: The results suggest the advantage of long term o-FPs, possibly with the injection of mitomycin C, for prognosis for curatively resected colorectal cancer patients.