Diverting ostomy prior to neoadjuvant treatment in rectal cancer should be used selectively: A retrospective single-center cohort study.

Background: Rectal cancer patients commonly benefit from neoadjuvant therapy before resection surgery. For these patients, an elective ostomy diversion is frequently considered, despite the absence of conclusive evidence when a diversion is advantageous. This is a retrospective observational single-center study on a 4-year consecutive rectal cancer cohort undergoing neoadjuvant therapy, aiming at improving the understanding of risks and benefits associated with ostomy diversion.

Material and method: Baseline characteristics, tumor-specific data, clinical events, and outcomes were collected using the Swedish Colorectal Cancer Registry and medical records.

Results: Thirty-two (30.2%) of the 106 included patients presented with endoscopic impassable tumors at diagnosis, of which 18 (56.2%) had diverting ostomy. Three out of 14 with impassable tumor and no diversion developed a bowel obstruction. None of the patients with an endoscopically passable tumor at diagnosis (n = 74) experienced a bowel obstruction. The elective diversions (n = 40) were not associated with serious complications (Clavien-Dindo grade ⩾ 3b). Patients with a diverting ostomy (n = 30) had similar time intervals from diagnosis to neoadjuvant treatment and to definite tumor resection as those without diversion but experienced more complex primary tumor resections in terms of blood loss and operation time.

Conclusion: An elective diverting ostomy is a relatively safe procedure in rectal cancer patients requiring neoadjuvant therapy. More than one out of five non-diverted patients with endoscopically impassable rectal tumors developed bowel obstruction and would potentially have benefited from an elective diversion.