Outcome Of Initially Unresectable Advanced And Metastatic Colorectal Cancer Patients Treated With First-Line Mfolfox6 Followed By Surgical Tumor Removal Of Metastases: Preliminary Results Of A Phase Ii Trial

e15122 Objective: The aim of this study was to evaluate the efficacy and tolerability of treatment with mFOLFOX6 followed by surgical tumor removal in patients (pts) with initially unresectable liver metastases and/or extrahepatic disease from colorectal cancer (CRC). Methods: This study was a multicenter, open-label clinical trial. Eligibility criteria defined pts with advanced and metastatic CRC deemed not optimally resectable. mFOLFOX6 (oxaliplatin 85 mg/m2, l-leucovorin 200 mg/m2, and fluorouracil [400 mg/m2 bolus followed by 2,400mg /m2 as a continuous 46-hour infusion]) was administered every 2 weeks for a maximum of 10 cycles. Resectability was the primary end point. Results: 26 pts (15M/11F; PS 0/1 19/7; median age: 60 years, rage 37–73) received 181cycles (median 7, range, 3–10) of mFOLFOX6. Main unresectable lesions were liver metastases in 10 pts and extrahepatic disease in 16 pts. Eleven pts (42%) had at least one grade 3 or greater adverse events. Sixteen pts (61%) achieved an objective response to mFOLFOX6 and 8 pts (31%) had a best overall response of stable disease. In 16 of these 24 pts who achieved the disease control, surgical tumor removal was performed (resectability 61%). The main reasons for initial unresectability in these 16 pts were the presence of liver metastases (6 pts), para-aortic lymph-node metastases (4 pts), carcinomatous peritonitis (4 pts), direct invasion to neighboring organ (2 pts). Four complications (25%) which were anastomotic leak, wound infection, chylous ascites, and cholangitis, were observed. At a median follow-up of 13 months (range 5 -21), 5 pts had relapsed after surgical tumor removal. The median time to progression (TTP) of the pts who underwent operation is not reached to date and those who did not undergo surgical removal is 8.6 months (log-rank p<0.05). Conclusions: Our data suggest that mFOLFOX6 has a significant antitumor activity in pts with not only liver metastases but also extrahepatic disease from CRC, allowing for successful resection of disease in a portion of pts initially not judged to be optimally resectable. No significant financial relationships to disclose.