Rectal adenocarcinoma: Surveillance and timing of surgical resection after neoadjuvant chemoradiotherapy in a retrospective cohort.

737 Background: There is some evidence relating delay of surgery (DS) by more than 8 weeks after the end of chemoradiotherapy and achievement of complete pathological response (ypCR). However, the relationship with overall survival (OS) seems to be negative. Methods: Records of 171 patients diagnosed from January 2003 to December 2011 with rectal adenocarcinoma T3/T4 and/or positive node staged by ultrasound or MRI were collected retrospectively from the Pathology Department database. Results: Of the 171 patients, 62% were male, median age at diagnosis 69.3 years (31.3 years -85.3 years). All of them received 50.4 Gy with different concomitant regimens (capecitabine, continuous infusion of fluoracil or bolus of fluoracil-leucovorin). 72.5% of the cohort received adjuvant chemotherapy. 13% of patients achieved ypCR, independently of DS (13.7% in DS vs 11.8%, p 0.722). OS was significantly worse among DS patients (67.9 months vs 54.8 months, p 0.016). In addition, more sphincter preservations (SP) were not ...