Long-term clinical and functional results of intersphincteric resection for lower rectal cancer

Intersphincteric resection (ISR) is an alternative to abdominoperineal resection (APR) for super-low rectal cancer. The aim of this study was to evaluate the long-term curability after ISR over an average 6-year observational period, to compare the postoperative functional outcomes for ISR with those for low anterior resection (LAR), and to determine whether ISR is a function-preserving surgery.

Between 2000 and 2007, a total of 77 consecutive patients with low rectal cancer underwent curative ISR. The curability outcomes for ISR, LAR, and APR were compared. We evaluated the postoperative defecation functions, Wexner incontinence score (WIS), and defecation quality of life (QOL) for a between-groups comparison (ISR/LAR).

The 5-year survival rate after ISR was 76.4 %, and the outcome was better than for APR (APR 51.2 %, LAR 80.7 %). Local recurrence after ISR occurred in 7.8 % of patients (APR 12.1 %, LAR 11.7 %). The average daily frequency of defecation was 3.7 times for the ISR patients and 3.2 times for the LAR patients, indicating no significant difference between the groups. Moreover, there were no significant differences between the groups for defecation functions. The WIS was 8.1 for ISR and 4.9 for LAR, and the defecation QOL for ISR and LAR was not significantly different (modified fecal incontinence QOL score: ISR 34.3, LAR 26.5).

The long-term clinical and functional results suggest that ISR may be the optimal sphincter-preserving surgery for patients with lower rectal cancers who cannot be treated with a double-stapling technique.