MFOLFOX6 with oxaliplatin stop-and-go strategy and oral S-1 maintenance therapy in advanced colorectal cancer: CCOG-0704 study.

569 Background: In metastatic colorectal cancer (mCRC), a combination of leucovorin and fluorouracil with oxaliplatin (FOLFOX) is one of the standard first-line regimen. The cumulative neurotoxicity of oxaliplatin often requires therapy to be stopped in patients who are still responding. The aim of this study was to evaluate modified FOLFOX6 (mFOLFOX6) with the intermittent oxaliplatin treatment and maintenance therapy with S-1, oral fluoropyrimidine derivative, in the first-line treatment of mCRC. Methods: Thirty patients with untreated mCRC were treated with six cycles of mFOLFOX6 (oxaliplatin 85 mg/m2, leucovorin 200 mg/m2, 5-fluorouracil bolus 400 mg/m2 and 5-fluorouracil continuous 2400 mg/m2, every 2 weeks) followed by maintenance therapy with oral S-1 (S-1 80- 120mg/body days 1-28, every 6 weeks). Reintroduction of mFOLFOX6 was scheduled after four cycles of S-1 or tumor progression. The primary study end point was duration of disease control (DDC). Results: Twenty of the 30 patients (66.7%) who ac...