Partial resection of rectum for rectal GIST by posterior approach

Objective The standard surgical treatment for gastrointestinal stromal tumor (GIST) is local resection. Colorectal GIST, which accounts for 5–10% of all GIST tends to develop in the lower rectum, making intra-abdominal approaches difficult and invasive. We perform partial resection of rectum with posterior approach for rectal GIST. We herein presented our procedure of posterior approach and retrospectively analysed the efficacy and safety of the posterior approach. Methods In a retrospective analysis from 2018 to 2023, data were collected from patients who underwent partial resection of rectum with posterior approach for rectal GIST. Patient characteristics, surgical outcomes, complications, prognosis and presence/absence of low anterior resection syndrome (LARS) were collected. Results Four patients with rectal GIST were included in this study. The median age was 50.5 years and all patients were male. The median operation time was 203.5 minutes, the median interoperative blood loss was 30 g, and the median initial tumour diameter was 29.5 mm. One patient underwent diverting ileostomy, and the ileostomy was closed one year after surgery. Complete pathological resection was achieved in all cases. Postoperative complications were observed in one patient: outlet obstruction of the diverting ileostomy and LARS and there were no other postoperative complications including anastomotic leakage. No recurrence was observed in the median follow-up of 33.5 months. Conclusions This study demonstrated that posterior approach is safe, low incidence of LARS, and facilitates complete resection, making it a valuable surgical option for rectal GIST.