<qa>  What was the value of the 1st line therapy for colorectal cancer?A multicenter Open-label, single-arm, phase III clinical trial is conducted on patients with histological stage IV colorectal cancer given irinotecan, leucovorin plus fluorouracil. The usefulness of this regimens as 1st line therapy for colorectal cancer was evaluated by the disease-free survival rate DFR, median survival time MST, incidence and severity of adverse event. 