대한대장항문학회

PURPOSE: The aim of this prospective study was to analyze anorectal physiologic and clinical outcomes of the colonic J-pouch-anal anastomosis compared with the traditional straight colorectal anastomosis after ultra-low anterior resection in patients<br>with rectal cancer, thus to define if this method of modified reconstruction has a functional superiority. METHODS: After total mesorectal excision for mid or low rectal cancers, patients were randomized to either a straight (n=23) or a colonic J-pouch<br>anastomosis (n=24) to the lowermost rectum or anal canal. Functional outcomes were compared between two groups using an anorectal manometry performed before and 1 year after surgery and a bowel function questionnaire administered 6 months and 1 year<br>postoperatively. RESULTS: Except the arithmetic level of anastomosis which was significantly higher in straight group than in pouch group (5.1+/-1.2 cm vs. 3.8+/-0.9 cm; P=0.0001), the two groups were well matched for demographic distribution,<br>pathologic stage, colonic segment used for neorectum and use of adjuvant therapies. Patients with colonic J-pouch anastomosis showed functional superiority in terms of frequency of bowel movements, degree of urgency at 6 months (P < 0.0001 and =0.03,<br>respectively) and 1 year postoperatively (P < 0.0001 and <0.05, respectively). Functional parameters, including incontinence to liquid stool and impaired discrimination between gas and stool were more pronounced in straight group after 6 months (P=0.04,<br>and <0.05, respectively), but the differences were not statistically significant after 1 year. Sensation of incomplete evacuation was not different statistically between groups at 6 months, but more common in J-pouch group at 1 year (39.1% vs. 8.3%;<br>P=0.04). As well as the length of high pressure zone and presence of rectoanal inhibitory reflex, there was no difference in sphincter pressure parameters between groups either before or 1 year after surgery. Maximal tolerable volume of the neorectum in<br>J-pouch group was 110.2+/-16.7 ml, which was significantly larger than that of 74.1+/-14.9 ml in straight group (P < 0.0001), and the neorectum in J-pouch group was significantly more compliant than that in straight group (6.1+/-1.9 vs. 3.3+/-2.1; P <<br>0.0001) in 1 year after surgery. CONCLUSIONS: Construction of a colonic J-pouch as a substitute for the rectum restores neorectal volume and compliance. Clinically it offers patients superior anorectal function compared with straight anastomosis. To<br>minimize evacuation difficulty associated with the pouch, optimal size of the pouch should be defined, thus to achieve an ideal balance between stool frequency/urgency and evacuation problems through larger prospective studies.<br>