The toxicity rates of two different regimens of irinotecan

The role of chemotherapy in the management of advanced colorectal cancer has been well established. Although fluorouracil has been the main cytotoxic agent used for colorectal cancer, newer drugs have been developed with promising results. In this study, we compared two different doses of irinotecan combined with 5-fluorouracil/leucoverin (5-FU/LV) in terms of progression-free and overall survival time and toxicity in the patients with recurrent or metastatic colorectal cancer. Patients were divided into groups. The first group received 350 mg/m2 irinotecan every three weeks. The second group was treated by 150 mg/m2 once a week for consecutive four weeks followed by a two-week drug-free interval. All the patients received 500 mg/m2 5-fluorouracil and 20 mg/m2 leucoverin every time they were treated with irinotecan. Median progression-free survival time was found to be 7 +/- 1 and 6 +/- 1 months in the first and seconds groups, respectively. Median overall survival time was found to be 19 +/- 4 and 12 +/- 4 months in the first and second groups, respectively. Alopecia grade 3-4 reaction rates were found to be significantly higher in the first group, while hematological grade 3-4 toxicity rates were higher in the second group. Although overall and progression-free survival curves were found to be similar in each group, hematological complications were less and response rates were higher in the 3-week course group. The 3-week course seemed to have a more comfortable administration schedule as well. So, we suggest the 350 mg/m2 once every 3 weeks regimen.