Irinotecan (CPT-11) in patients with advanced colon carcinoma relapsing after 5-fluorouracil-leucovorin combination.

The purpose of the present study was to investigate the association between performance status (PS) and mean dose of irinotecan (CPT-11) in patients with recurrent advanced colorectal cancer relapsing after 5-fluorouracil and leucovorin chemotherapy. Patients who had completed their last chemotherapy course with 5-fluorouracil and leucovorin for at least 6 weeks and progressed were included. Based on PS, we administered a starting dose of 250 mg/m(2) in patients with a PS 70-80 (group A), and 350 mg/m(2) for those with a PS > 80 (group B). Of a total of 90 treated patients, all were evaluable, 18 had a partial response (PR) (20%), 39 stable disease (43%), and 15 progressed (37%). No significant difference was noticed between patients with PS > or = 90 or < or = 80 (p = 0.925), or between those who received a mean dose of CPT-11 > or = 300 or < or = 300 (p = 0.602), for response, survival and time to progression. Toxicity was increased in group B as expected, with significant differences for acute cholinergic syndrome (p = 0.02), diarrhea after the first 24 h (p = 0.03) and severe diarrhea (p = 0.03). According to these results, we conclude that response to CPT-11 is independent of its dose, and that a dose of 250 mg/m(2) every 3 weeks might be a cost-effective and less toxic alternative in this setting. However, further adequately powered phase II or III randomized studies might be required in order to confirm this observation.