Outcomes of ultra-low anterior resection combined with or without intersphincteric resection in lower rectal cancer patients.

purposeWe evaluated the current practice of ultra-low anterior resection (uLAR) in patients with lower rectal cancer and compared uLARs using mostly transabdominal approach with or without intersphincteric resection (ISR).

methodsA total of 624 consecutive lower rectal cancer patients undergoing curative uLAR were prospectively enrolled as ISR+ vs. ISR- groups (329 vs. 295 patients) between 2005 and 2012. The ISR+ group additionally received levator-sphincter reinforcement after distal resection.

resultsThe circumferential resection margin (CRM) + rate (≤1 mm) was 2.1 % in the two groups. Postoperative ileus occurred more in the ISR- group than in the ISR+ group (p = 0.02). Substantial erectile dysfunction occurred 1.8 times more frequently in the ISR- group than in the ISR+ group (32 vs. 18.1 %; p = 0.01) among male patients at 2 years postoperatively. The urge to defecate volume and maximal tolerance volume, closely correlated with maximal squeezing pressure and/or mean resting pressure, did not differ between patients with and without chemoradiotherapy until 24 months postoperatively. Nevertheless, the urge to defecate volume was lesser in the ISR- group than in the ISR+ group at 24 months postoperatively (p = 0.022). For 301 patients in which >5 years had elapsed postoperatively, the mean 5-year local recurrence rate was 4.3 %, and the 5-year disease-free and overall survival rates were 78.9 and 92 %, respectively, without differences between the two groups.

conclusionsCompared with uLAR without ISR, the transabdominal ISR with levator-sphincter reinforcement provides a safe resection plane with competent CRM, concurrently reduces substantial complications, and marginally promotes recovery of neorectal function.