The comparison of FOLFOX regimens with different doses of 5-FU for the adjuvant treatment of colorectal cancer: a multicenter study

Purpose: We aim to compare the efficiency and toxicity of three different 5-fluorouracil (5-FU) administration types in 5-FU, leucovorin, and oxaliplatin (FOLFOX) combination treatment for adjuvant therapy in colorectal cancer (CRC). Methods: Five hundred and seventy patients with stage III colorectal carcinoma who received different FOLFOX regimens after curative resection were included. Patients were divided into three groups as FOLFOX-4, modified FOLFOX-6 (mFOLFOX-6), and mFOLFOX-4 for comparison of toxicity and disease-free survival (DFS) and overall survival (OS) times. Results: Three-year DFS rates for FOLFOX-4, mFOLFOX-6, and mFOLFOX-4 groups were 65%, 72%, and 72%, respectively. Five-year OS rates for FOLFOX-4, mFOLFOX-6, and mFOLFOX-4 groups were 69%, 75%, and 67%, respectively. There was no statistically significant difference between the three treatment groups in terms of DFS and OS (p = 0.079, and p = 0.147, respectively). Among grade 1–2 adverse events (AE), thrombocytopenia, neuropathy, and stomatitis were more common in the mFOLFOX-6-treated group. The frequency of grade 1–2 nausea and vomiting were similar in mFOLFOX-6 (36.3% and 24%, respectively) and mFOLFOX-4 (32.4% and 24.7%, respectively) groups but were higher than that in the FOLFOX-4 (19.5% and 11.3%, respectively) group. Among the most common grade 3–4 AE, neutropenia (53.4%, 9%, and 13.5%, respectively) and diarrhea (10.5%, 2.2%, and 2.4, respectively) were more common in FOLFOX-4. The rate of anemia and febrile neutropenia was similar in treatment groups (p = 0.063, and p = 0.210, respectively). Conclusion: In the adjuvant treatment of stage III CRC patients, three different 5-FU administration types in FOLFOX combination treatment can be used with similar efficiency and manageable toxicity.