Mitomycin-C in combination with fluoropyrimidines in the treatment of metastatic colorectal cancer after oxaliplatin and irinotecan failure.

Purpose: To retrospectively evaluate the efficacy and tolerability of mitomycin-C (MMC) in combination with fluoropyrimidines as salvage 3rd -or 4th-line therapy in metastatic colorectal cancer (MCRC) patients.
Methods: All patients in this study had previously failed oxaliplatin and irinotecan-based chemotherapy. Patients were treated with MMC (6 mg/m(2) intravenously/i.v.) on day 1 in combination with either oral UFT (500 mg/m(2)) and oral leucovorin (LV) (30 mg) on days 1-14 every 3 weeks (group A) or infusional 5-fluorouracil (5-FU) by deGramont regimen with i.v. LV (200 mg/m(2)) on days 1 and 2, every 2 weeks (group B).
Results: Thirty-nine MCRC patients were analyzed. Twenty-two of them were in group A and 17 in group B. Thirty-three were evaluable for clinical efficacy. The clinical benefit in the intent-to-treat (ITT) population was 30.8%. Median progression free survival (PFS) was 6 months (95% confidence interval/ CI 4-8) and median overall survival (OS) 9 months (95% CI 6.5-11.5). Median PFS was 3 months (95% CI 2.4-3.6) in group A and 7 months (95% CI 5.1-8.9) in group B (p=0.009). Median OS was 7 months (95% CI 4.3-9.7) in group A and 12 months (95% CI 5.4-18.6) in group B (p=0.422). The combination of MMC and fluoropyrimidines was generally well tolerated. The most common severe toxicities were nausea and vomiting, neutropenia, hepatotoxicity and diarrhea.
Conclusion: MMC in combination with fluoropyrimidines is safe and active in heavily-pretreated MCRC patients. This combination remains a viable option in these patients. However, better therapies are urgently needed.