Abstract

Background: The standard treatment of locally advanced rectal cancer (RC) of the middle and lower third of the rectum is neoadjuvant chemoradiotherapy (XRQT) follow by oncologic resection. After this treatment in 15-25% of the cases, the pathologist reports complete pathological response (pCR). Aim: To describe demographic, clinical and survival data of patients with pCR undergoing chemoradiotherapy and radical resection for RC. Material and Methods: Historic cohort study. In a prospectively maintained database between 2000 and 2010, we identified patients with RC, who underwent neoadjuvant chemoradiotherapy according to protocol, followed by radical resection. The preoperative staging was obtained by clinical examination, endoscopy, rectal ultrasound, CT scan of chest, abdomen and pelvis and pelvic MRI. Demographic data, tumor location, time between the end of XRTQ and surgery, postoperative staging (according AJCC) and survival, were collected. Results: 119 patients received preoperative XRTQ, 65% male, with a mean age of 58 years. The most frequent tumor site was the lower third (63%). Surgery was performed 8 weeks after the end of XRTQ. Of 119 patients with XRTQ, 15.1% had a pCR. Overall survival was 75%, and cancer-specific survival was 80.4% at 5 years in patients without pCR. For patients with pCR, the 5 year survival estimates for overall and cancer specific survival was 100%. We did not identify factors associated with pCR. Conclusions: In this study, pCR was comparable to other larger series reported elsewhere. No factors associated with pCR were identified.