OBJECTIVETo investigate the application value of the Overlap method in digestive tract reconstruction of totally laparoscopic left colectomy(TLLC) and its potential advantage.

METHODSThe retrospective cohort study was adopted. Clinicopathological data of 16 patients with left colon cancer who underwent TLLC and Overlap anastomosis between August 2016 and August 2017 at Tangdu Hospital were retrospectively collected as Overlap group. Twenty-one patients who underwent laparoscopic assisted left colectomy (LALC) between January 2015 and July 2016 at Tangdu Hospital were used as control (traditional group). The intraoperative and postoperative data were compared between the two groups. During digestive tract reconstruction in the Overlap group, the proximal colon and distal colon were lined up side by side; a side-to-side anastomosis was conducted on colic band with a 60 mm linear stapler; and the common entry hole was closed using running suture. While in traditional group, the bowel was pulled out of abdominal wall through the assisted incision; the sample was resected and a proximal and distal end-to-end anastomosis was performed.

RESULTSIn Overlap group, 10 cases were male and 6 cases were female, with a mean age of (66.4±4.8) years and a BMI of (23.6±2.3) kg/m; the tumor located in distal transverse colon in 1 case, in splenic flexure in 2 cases, in descending colon in 4 cases, in upper sigmoid colon in 9 cases. TLLC was successfully completed in all the cases without conversion to laparotomy. In traditional group, 12 cases were male and 9 cases were female, with mean age of (65.9±5.8) years and BMI of (22.7±2.8) kg/m; the tumor located in the distal transverse colon in 1 case, in the splenic flexure in 3 cases, in the descending colon in 6 cases, in the upper sigmoid colon in 11 cases. No statistically significant differences in baseline data were found between the two groups (all P>0.05). Compared to the traditional group, the total operation time was shorter [(143.4±11.1) minutes vs. (166.4±16.5) minutes, t=4.792, P=0.000], the anastomosis time was prolonged [(44.3±3.3) minutes vs. (22.4±3.0) minutes, t=-20.948, P=0.000], the amount of bleeding was reduced [(46.6±13.6) ml vs. (70.5±20.0) ml, t=4.106, P=0.000], and the incision length was shorter [(3.9±0.9) cm vs. (6.7±1.3) cm, t=7.056, P=0.000] in the Overlap group. There were no significant differences in lymph nodes harvested (17.3±2.9 vs. 15.5±3.0), time to flatus [(2.8±1.3) days vs. (2.6±1.0)days], postoperative complications [6.2%(1/16) vs. 9.5%(2/21)] and postoperative hospitalization [(4.6±1.4) days vs.(4.7±1.2) days] between the two groups (all P>0.05).

CONCLUSIONThe Overlap reconstruction method in totally laparoscopic left colectomy is a safe and feasible procedure, and provides less injury and better cosmetic outcome of abdominal wall.