Purpose: Fluorouracil (FU)-leucovorin (LV), irinotecan, and oxaliplatin administered alone or in combination have proven effective in the treatment of advanced colorectal cancer (CRC). Combination protocols using FU-LV with either irinotecan or oxaliplatin are currently regarded as standard first-line therapies in this disease. However, the importance of the availability of all three active cytotoxic agents, FU-LV, irinotecan, and oxaliplatin, on overall survival (OS) has not yet been evaluated.
Materials and methods: We analyzed data from seven recently published phase III trials in advanced CRC to correlate the percentage of patients receiving second-line therapy and the percentage of patients receiving all three agents with the reported median OS, using a weighted analysis.
Results: The reported median OS is significantly correlated with the percentage of patients who received all three drugs in the course of their disease (P =.0008) but not with the percentage of patients who received any second-line therapy (P =.19). In addition, the use of combination protocols as first-line therapy was associated with a significant improvement in median survival of 3.5 months (95% CI, 1.27 to 5.73 months; P =.0083).
Conclusion: Our results support the strategy of making these three active drugs available to all patients with advanced CRC who are candidates for such therapy to maximize OS. In addition, our findings suggest that, with the availability of effective salvage options, OS should no longer be regarded as the most appropriate end point by which to assess the efficacy of a palliative first-line treatment in CRC.