RESUMEN
BACKGROUND: In this study, we attempted to determine the efficacy and toxicity of decreasing dosage of irinotecan plus 5-fluorouracil (5-FU) and leucovorin (LV) in the treatment of advanced colorectal cancer. METHODS: A total of 250 mg/m2 Irinotecan (CPT-11) intravenous infusion for 90 minutes was administered every 3 weeks. A 24-hour intravenous infusion with 2000 mg/m2 5-FU and 200 mg/m2 LV was administered through a port-A catheter system weekly for 2 consecutive weeks. Each treatment cycle was repeated every 3 weeks. Progression-free survival and survival curves were drawn according to Kaplan-Meier method. Tumor responses were determined according to the RECIST guidelines. Toxicities were evaluated using the WHO criteria. RESULTS: Thirty-eight patients were enrolled from September 2001 through October 2004. The median number of treatment courses was 8.1 (range, 1-14). Based on the intent-to-treat principle, the response rate was 39.5% (95% CI: 25.4-54.4%) which included 5.3% complete response (CR) and 34.2% partial response (PR). The time to tumor progression was 8.4 months (range, 2-12 months). The median time of survival was 18.4 months (range, 4-26 months). The major toxicities were grade 1 neutropenia and grade 2 diarrhea. Toxic death was not found in this study. The efficacy of this regimen was compatible with the reports of the clinical trials in the United States and European countries but fewer incidence of toxicity was found in our results. CONCLUSION: The results revealed that our combination regimen of 5-FU/LV + CPT-11 is a highly effective and acceptable protocol. This treatment is easily performed in an outpatient clinic. The biggest advantage is that all patients were intensively cared by the physicians to maintain a quality of life, and only 26.3% of patients showed progressive disease. Therefore, this regimen may be considered to be used in the treatment of patients with terminal cancer. A further randomized study comparing this regimen with oral fluoropyrimidines plus irinotecan is warranted.