Phase II study of irinotecan as first-line chemotherapy for patients with advanced colorectal carcinoma

BACKGROUND: The objective of this multicenter, open-labeled, Phase II study performed in Spain was to assess the efficacy and safety of irinotecan (CPT-11) as first-line chemotherapy for patients suffering from advanced colorectal carcinoma (CRC). METHODS: Patients with histologically proven CRC and at least one bidimensionally measurable lesion, ages 18-70 years, with a performance status < or = 2, normal analytical values, and no prior chemotherapy or only adjuvant chemotherapy completed before study entry were selected. The treatment schedule was CPT-11 350 mg/m(2) intravenously administered once every 3 weeks. Both tumor response and toxicity were assessed using the World Health Organization and National Cancer Institute common toxicity criteria. Changes in performance status, weight, and symptoms also were measured. RESULTS: Sixty-five patients (44 chemotherapy-na?ve patients and 21 patients who completed prior adjuvant treatment) were enrolled. Of these, 24.7% of patients responded to the treatment, and 41.5% of patients had stable disease. Patients who had not received prior adjuvant chemotherapy had a lower rate of progression on therapy (27.3%) compared with those who had received prior adjuvant chemotherapy (42.9%). The median survival was 19.9 months (range, 0.3-29.3 months). No significant differences were found in the median survival between chemotherapy-na?ve patients and patients who had received previous chemotherapy. Grade 3-4 diarrhea and neutropenia were the most frequent severe toxic events, which were observed in 23.1% and 30.8% of patients and in 5.9% and 10.9% of the cycles, respectively. CONCLUSIONS: The current antitumor efficacy results show that 350 mg/m(2) of CPT-11 administered every 3 weeks is an active and feasible first-line chemotherapy regimen for patients with CRC. Finally, the overall safety data confirmed that CPT-11 is a well tolerated treatment.