Activity and toxicity of oxaliplatin plus raltitrexed in 5-fluorouracil refractory metastatic colorectal adeno-carcinoma.

Background: This study evaluated the antitumor efficacy and safety of a novel oxaliplatin/raltitrexed combination in pretreated advanced colorectal cancer patients. Patients and Methods: Forty-five patients with 5- fluorouracil-refractory metastatic colorectal cancer received raltitrexed 3.0 mg/m 2 as a 15-minute intravenous (i.v.) infusion, followed 45 min later by l-OHP 130mg/m 2 iv as 2-h venous infusion on 1 day every 3 weeks. All patients had histologically proven metastatic colorectal cancer, age 18-75, measurable disease and normal baseline biological values. Most patients (60%) had >2 disease sites. All patients were assessed for safety and also for response according to an intent- to-treat fashion. Results: The overall response rate was 29% (95% CL 16%-44%) including one CR (2%) and 12 PR (27%). Six patients (16%) showed a stabilization of disease for a tumor growth control rate of 45%. The median time to progression was 4 months (range 1-12+) and median overall survival was 9 months (range 1-29+). Conclusion: These data confirm that this oxaliplatin/raltitrexed combination is effective against metastatic colorectal carcinoma, well tolerated with low grade toxicity and easy to administrer. Further evaluation of this regimen seems warranted as an alternative to fluoropyrimidine-based combinations. Colorectal carcinoma is one of the most common cancer types in the Western world, with more than 30% of cases diagnosed at advanced stage (1). Approximately 50% of all newly diagnosed patients ultimately will develop recurrent and/or metastatic disease. These patients are therefore potential candidates for palliative chemotherapy.