Long-term results of extended intersphincteric resection for very low rectal cancer: a retrospective study

Intersphincteric resection (ISR) has become an increasingly popular optional surgical tool for the treatment of very low rectal cancer. The purpose of this study was to assess the long-term oncological and functional outcomes of intersphincteric resection for T2 and T3 rectal cancer situated below 4 cm from the anal verge.

A total of 62 consecutive patients with very low rectal cancer who underwent ISR from 2001 to 2010 were classified into standard ISR for T2 lesions (Group I, n = 24) and extended ISR for T3 lesions (Group II, n = 38).

The 5-year overall survival rates were 95.8% for group I and 94.7% for group II. The 5-year recurrence-free survival rates were 87.5% for group I and 86.8% for group II. Bowel functions were evaluated at the 12(th) and 24(th) months after ileostomy closure in both groups. The frequency of bowel evacuation was higher in patients who underwent extended ISR than in those who underwent standard ISR at the 12(th) month (p < 0.05). However, at the 24(th) month, the frequencies decreased in both groups, exhibiting no significant difference. In the comparison based on the Kirwan classification, group I showed better continence status than group II but no significant difference. The Wexner scores of both groups revealed that the average score was 7.33 ± 2.8 in group I and 8.18 ± 2.9 in group II at the 12(th) month, and at the 24(th) month, the average score was 5.21 ± 1.7 in group I and 5.82 ± 1.9 in group II. There were no statistically significant differences between the two groups.

Extended ISR with quadrant resection of the upper external sphincter achieved good post-operative continence status, OS and RFS. Extended ISR can thus be an alternative to abdominoperineal resection for very low rectal cancer without compromising the chance of cure and improving quality of life.