Neoadjuvant chemoradiation therapy with capecitabine (X) plus cetuximab (C), and external beam radiotherapy (RT) in locally advanced rectal cancer (LARC): ABCSG trial R03

4109 Background: Pre-operative chemoradiation is a standard treatment for LARC. X and C are synergistic with radiotherapy and active in colorectal neoplasms. This phase II multicenter trial was designed to assess the feasability and tolerability of a preoperative combination of X, C, plus RT in patients with LARC. Secondary endpoints were downstaging-rate and induction of complete pathological response (CPR). Only patients (pts.) with MRT-documented T3/T4-tumours were included. Methods: Pts. with potentially resectable cT4 or cT3 LARC (lower/mid rectum) were enrolled. Chemoradiotherapy consisted of X (825mg/sqm twice daily on RT-days weeks 1–4), C (400mg/sqm loading dose once per week, 200mg/sqm weekly x 4) and pelvic RT 3D conformation technique (1.8Gy/day, 45Gy total). Surgery was performed 28–42 days after completion of RT. Results: 31 pts. were enrolled, median age was 61 years (range 41 to 80), PS 0: 22 pts. (71%), PS 1: 8 pts. (26%), PS 2: 1 pt. (3%). 21 pts. (68%) presented with cT4, 10 pts. (32%) ...