Sphincter-Preserving Surgery versus Abdominoperineal Resection for Low Rectal Cancer

Abstract

Introduction: For low rectal cancer, achieving negative margins while preserving sphincter function remains a surgical challenge. Intersphincteric resection (ISR) and other ultralow anterior resections have been developed as alternatives to abdominoperineal resection (APR). This review compares oncologic and functional outcomes.

Methods: A systematic review was conducted of comparative studies between ISR (partial, subtotal, or total) and APR for tumors within two centimeters of the dentate line. Outcomes included local recurrence, overall survival, and major low anterior resection syndrome (LARS) rates.

Results: Nineteen studies (mostly retrospective) were analyzed. Local recurrence rates were similar between ISR and APR, ranging from five to fifteen percent. Overall survival did not differ significantly. However, major LARS occurred in forty to sixty percent of ISR patients, severely impacting quality of life. Postoperative complications, including anastomotic leak, occurred in about twenty percent of ISR cases.

Discussion: ISR can achieve comparable oncologic safety in selected T1–T2 and some T3 tumors after neoadjuvant therapy. The decision to perform ISR must balance oncologic adequacy against functional devastation. Patients with poor preoperative sphincter function or very low, bulky tumors may still be best served by APR. Preoperative counseling regarding LARS is essential.

Conclusions: Intersphincteric resection offers a sphincter-preserving alternative to APR without compromising oncologic outcomes, but functional morbidity is substantial. Careful patient selection is mandatory.