Weekly single agent irinotecan versus irinotecan, 5-flurouracil, and folinic acid (FOLFIRI) in advanced colorectal cancer

Colorectal cancer is a common cancer worldwide. As regards the incidence, CRC considered the third cancer among men after prostate and lung cancer and the second among women after breast cancer.1 CRC represent about 15% of all cancers and considered the second leading cause of cancer deaths among western countries. About 50% of CRC patients developed metastatic disease despite of adjuvant therapy.2 Palliative chemotherapy plays a major role in treatment of colorectal cancer (CRC) patients by improving quality of life and prolonging the survival. 5-Flurouracil (FU) and Leucovorin (LV) combination were the standard of care for about 40 years in spite of their minimal impact on survival.3 Oxaliplatin and irinotecan demonstrate remarkable activity against advanced CRC and showed survival improvement, either alone or in combination with 5-FU\LV.4 Irinotecan is one of the topoisomerase I inhibitors. Topoisomerase I inhibition leads to double-strand DNA breaks which stimulate cell apoptosis. Addition of irinotecan to 5 FU\LV significantly improves survival in advanced CRC patients.5 So, US Food and Drug Administration (FDA) approved FOLFIRI regimen as first line therapy in metastatic CRC.4 In advanced CRC patients progressed after 5-FU based therapy, weekly single agent irinotecan show promising result either by disease control or improving survival.6 We conducted this study to compare the efficacy and tolerability of two irinotecan regimens (weekly irinotecan and FOLFIRI regimen) in advanced colorectal cancer.