Prospective phase II trial of second-line FOLFIRI in patients with advanced colorectal cancer including analysis of UGT1A1 polymorphisms: FLIGHT 2 study.

AIM This is a multicenter phase II study to assess the efficacy and toxicity of FOLFIRI treatment agents in full and the influence of UGT1A1*28 polymorphism in Japanese patients with advanced/metastatic colorectal cancer (mCRC). PATIENTS AND METHODS Fifty patients with mCRC participated in this study. Treatment consisted of FOLFIRI (irinotecan; 150 mg/m(2)) as second-line chemotherapy; 34 patients consented to the evaluation of UGT1A1 genotype. RESULTS The overall response rate was 12% for all 50 evaluable patients; 31 patients (62.0%) had stable disease, and only in 12 (24.0%) did disease progress. The median progression-free survival was 5.8 months. The tolerance treatment was acceptable, with only 15 out of 50 patients (30%) experiencing grade 3/4 neutropenia, and grade 4 thrombocytopenia was observed in only one case. Grade 3 non-hematological adverse reactions included stomatitis in three, diarrhea in one, and a clinically insignificant increase in serum alkaline phosphatases in one patient, respectively. There was no definite relation between the UGT1A1*28 polymorphism and toxicity. CONCLUSION Standard FOLFIRI regimen can be administered to Japanese patients. The results showed good tolerability and efficacy for second-line FOLFIRI, provided that evaluation of UGT1A1 polymorphism is properly implemented before the start of the chemotherapy.