Randomized comparison of two schedules of fluorouracil and leucovorin in the treatment of advanced colorectal cancer

Abstract

Purpose: To compare two commonly used schedules of fluorouracil (5FU) and leucovorin in the treatment of patients with advanced metastatic colorectal cancer. Each of these dosage administration schedules has been demonstrated to be superior to single-agent bolus 5FU in previous controlled trials.

Patients and methods: Three hundred seventy-two ambulatory patients with metastatic colorectal cancer were stratified according to performance status, and presence and location of any measurable indicator lesion(s). They were then randomized to receive chemotherapy with one of the following regimens: (1) intensive-course 5FU plus low-dose leucovorin (5FU 425 mg/m2 plus leucovorin 20 mg/m2 intravenous [IV] push daily for 5 days with courses repeated at 4- to 5-week intervals); (2) weekly 5FU plus high-dose leucovorin (5FU 600 mg/m2 IV push plus leucovorin 500 mg/m2 as a 2-hour infusion weekly for 6 weeks with courses repeated every 8 weeks).

Results: Three hundred sixty-two of 372 patients randomized (97.3%) were eligible and included in the analysis. Three hundred forty-six patients (95.6%) have died. There were no significant differences in therapeutic efficacy between the two 5FU/leucovorin regimens tested with respect to the following parameters: objective tumor response (35% v 31%), survival (median, 9.3 v 10.7 months), and palliative effects (as assessed by relief of symptoms, improved performance status, and weight gain). There were significant (P < .05) differences in toxicity, with more leukopenia and stomatitis seen with the intensive-course regimen, and more diarrhea and requirement for hospitalization to manage toxicity with the weekly regimen. Financial cost was also higher with the weekly regimen.

Conclusion: Intensive-course 5FU plus low-dose leucovorin appears to have a superior therapeutic index compared with weekly 5FU plus high-dose leucovorin using the dosage administration schedules applied in this study based on similar therapeutic effectiveness, but lower financial cost, and less need for hospitalization to manage chemotherapy toxicity.