Abstract
<title>Abstract</title> <p> <bold>Background</bold> Adhesive small bowel obstruction (ASBO) is a significant postoperative complication following rectal cancer surgery. However, the impact of preoperative chemoradiotherapy (CRT) on early postoperative ASBO after abdominoperineal resection (APR) remains unclear. <bold>Methods</bold> This retrospective single-center study included patients who underwent APR for rectal cancer between January 2020 and December 2025. Patients were divided into CRT and non-CRT groups. Postoperative ASBO was diagnosed based on clinical and radiological findings. Patient characteristics, perioperative factors, and clinical outcomes were compared between the two groups. <bold>Results</bold> A total of 37 patients were included, 13 of whom received preoperative CRT. ASBO occurred in four patients (10.8%), with a higher incidence in the CRT group than in the non-CRT group (23.1% vs. 4.2%). All ASBO cases developed during the early postoperative period (postoperative days 6–15) and were attributed to severe pelvic adhesions. Conservative management was unsuccessful in all three ASBO cases in the CRT group, necessitating surgical intervention with intestinal bypass. Lateral lymph node dissection was not associated with the occurrence of ASBO. <bold>Conclusions</bold> Preoperative CRT may be associated with early-onset, treatment-resistant ASBO after APR for rectal cancer. Careful postoperative monitoring is warranted in patients receiving CRT. </p>