[Clinical significance of bolus 5-fluorouracil for recurrent or metastatic colorectal cancer treated with FOLFOX+ BevacizumabTherapy].

PURPOSE

For recurrent or metastatic colorectal cancer, a combination of leucovorin and fluorouracil with oxaliplatin (FOLFOX)is a standard first-line regimen. Although various FOLFOX regimens are widely used, the neutropenia caused by FOLFOX is often problematic. The purpose of this study was to evaluate the clinical significance of bolus 5-fluorouracil for recurrent or metastatic colorectal cancer treated with FOLFOX+bevacizumab therapy.

METHODS

Thirty-nine patients who had metastatic lesions from colorectal cancer treated with FOLFOX+Bevacizumab at the Osaka Rosai Hospitalfrom January 2008 to December 2009 were included. This study compared mFOLFOX6+Bevacizumab(mF6+BV)with mFOLFOX7+Bevacizumab( mF7+BV)to assess the clinical significance of bolus 5-fluorouracil.

RESULTS

Grade 3/4 neutropenia was significantly less in mF7+BV(58. 8%: median 12 courses)than in mF6+BV(22. 7%: median 11 courses)(P=0. 02). Response rates were 52. 9%in mF6+BV and 54. 5%in mF7+BV(P=N. S.). Relative dose intensities(RDI)during the first four courses of oxaliplatin were 89% in mF6+BV and 94. 6% in mF7+BV, respectively(P=N. S.). Completion rates were 52. 9% in mF6 +BV and 68. 2% in mF7+BV, respectively(P=N. S.). The main factors in RDI and completion rate decrease were hematologic toxicity. The median PFS was 12. 5 months in mF6+BV compared with 14. 8 months in mF7+BV(P=0. 91).

CONCLUSIONS

The mFOLFOX7+BV regimen seems beneficialas first-line therapy in recurrent or metastatic colorectal cancer, demonstrating a decreased toxicity with an acceptable response rate and PFS. Bolus 5-fluorouracil may be unnecessary in a FOLFOX regimen. Further study is needed to fully evaluate bolus 5-fluorouracil.