NEW YORKResponse and overall survival were significantly improved with use of irinotecan(Drug information on irinotecan) (Camptosar), fluorouracil(Drug information on fluorouracil), and leucovorin, compared with fluorouracil/leucovorin alone, in a randomized study involving 683 patients with previously untreated metastatic colorectal cancer.
Leonard B. Saltz, MD, of Memorial Sloan-Kettering Cancer Center, reported the results for the Irinotecan Study Group at the 36th Annual Meeting of the American Society of Clinical Oncology, and the full data have now been published (N Engl J Med 343:905-914, 2000).
Patients received bolus fluorouracil 500 mg/m² plus leucovorin 20 mg/m² plus irinotecan 125 mg/m² weekly for 4 weeks or the Mayo Clinic bolus fluorouracil/leucovorin regimen.
Dr. Saltz reported a confirmed response rate of 39% for patients receiving irinotecan therapy vs 21% for those assigned to fluorouracil/leucovorin (P < .001). Median progression-free survival was 7 months for those on irinotecan vs 4.3 months for those on fluorouracil/leucovorin alone (P = .004). Median overall survival was 14.8 months for the irinotecan group vs 12.6 months for fluorouracil/leucovorin (P = .04). Analysis of quality-of-life data showed no significant differences between the groups.
The irinotecan combination is now being compared with a weekly regimen of fluorouracil/leucovorin as adjuvant therapy for patients with stage III colon cancer to determine whether it will increase rates of cure in patients with an earlier stage of the disease, Dr. Saltz said.