OBJECTIVETo evaluate the radical effect and postoperative anal function of total mesorectum excision (TME) combined with different intersphincter resection (ISR) in treatment of T1 and T2 stage ultra-low rectal cancer.

METHODSClinical data of 102 T1 and T2 stage ultra-low colorectal cancer patients who received TME combined with different ISR from January 2004 to December 2013 in our department, including 33 cases of complete internal anal sphincter excision ISR (complete ISR group), 39 cases of partial internal anal sphincter excision ISR (partial ISR), 30 cases of partial dentate line reservation ISR (dentate line group). All the operation procedures followed the principles of TME. Radical conditions were compared and similarly, postoperative anal function was evaluated by Williams classification standard among 3 groups.

RESULTSThe general information, such as gender, age, BMI, maximum diameter of tumor, distance of tumor edge to dentate line, TNM staging, degree of differentiation among 3 groups had no statistically significant differences (all P>0.05). The operation time, intraoperative blood loss, length of removed intestinal canal, resection margin, the harvested number of lymph nodes, and postoperative complications among 3 groups also had no statistically significant differences (all P>0.05). Twelve months after surgery, good anal function rate in part ISR group and dentate line group was 100%, significantly better than that in complete ISR group (75.8%) with significant difference (χ2=4.654, P=0.015).

CONCLUSIONTME combined with ISR surgery in treatment of T1 and T2 stage ultra-low rectal cancer is safe and effective, which, as far as possible to preserve partial internal sphincter and dentate line on the premise of the guarantee of radical condition, can help to improve the postoperative anal function.