A Multi-Center Randomized Controlled Trial Of Mfolfox6 With Or Without Radiation In Neoadjuvant Treatment Of Local Advanced Rectal Cancer (Fowarc Study): Preliminary Results.

3500 Background: The FOWARC study investigates whether peri-operative mFOLFOX6 chemotherapy (CT) improves disease-free survival (DFS) in locally advanced rectal cancer. Methods: Between 01/2011-02/2015, patients with rectal cancer within 12 cm from the anal verge, clinical stage II-III were randomly assigned to received 5-FU with radiation(RT) (control arm), or receive mFOLFOX6 with RT (FOLFOX-RT arm), or receive 4-6 cycles of mFOLFOX6 alone (FOLFOX arm), post-operative RT is allowed if needed. Primary endpoint is DFS. Here we report the preliminary results. Results: 495 patients were randomized (165 in each arm). 92% of patients accomplished at least 46 Gy of RT in FOLFOX-RT arm compared to 86.8% in control arm. 5% of FOLFOX arm patients received post-op RT. R0 resection rate was 90.1%, 88.2%, and 91.2%, respectively in control arm, FOLFOX-RT arm and FOLFOX arm. The pCR rate was 12.5%, 31.3% and 7.4% respectively (P = 0.001). Good down staging (ypTNM 0-1) was achieved in 34.7%, 57.8%, and 37.9% of patien...