Long-term outcome of local excision after preoperative chemoradiation for ypT0 rectal cancer

Local excision, as an alternative to radical resection for patients with pathological complete response (ypT0) after preoperative chemoradiation, is under investigation.

The aim of the present study was to evaluate the long-term clinical outcome of a selected group of patients with ypT0 rectal cancer who underwent local excision with transanal endoscopic microsurgery as a definitive treatment.

Between 1993 and 2013, 43 patients with rectal adenocarcinoma underwent complete full-thickness local excision with a transanal endoscopic microsurgery procedure after a regimen of chemoradiation. In all patients, rectal wall penetration was preoperatively assessed by endorectal ultrasound and/or magnetic resonance. Chemoradiation and transanal endoscopic microsurgery were indicated in patients refusing radical procedures or patients unfit for major abdominal procedures.

Patient characteristics, operative record, pathology report, and tumor recurrence were analyzed at a median follow-up of 81 months. The potential prognostic factors for recurrence, screened in univariate analysis, were analyzed by multivariate analysis by using the Cox regression model.

Thirteen patients (30.2%), without residual tumor in the surgical specimen (ypT0), were treated with transanal endoscopic microsurgery only. In this ypT0 group, 2 patients (15.4%) had postoperative complications: 1 bleeding and 1 suture dehiscence. Postoperative mortality was nil. No local and distal recurrences were observed, and no tumor-related mortality occurred. In 30 patients (69.8%), partial tumor chemoradiation response or the absence of tumor chemoradiation response was observed. In this group, recurrence occurred in 17 patients (56.7%).

The study was limited by its retrospective nature, different protocols of chemoradiation and preoperative staging over time, and the small sample size.

Local excision with transanal endoscopic microsurgery can be considered a definitive therapeutic option in patients with rectal cancer treated with preoperative chemoradiation, when no residual tumor is found in the specimen. In this selected group, local excision offers excellent results in terms of survival and recurrence rates. In the presence of residual tumor, transanal endoscopic microsurgery should be considered as a large excisional biopsy (see Video, Supplemental Digital Content 1, http://links.lww.com/DCR/A157).