To investigate the learning curve of laparscopic sphincter-saving resection for rectal cancer and its influence on postoperative complications and oncological safety.

Between Sep. 2009 and Dec. 2014, 208 consecutive patients who were scheduled to undergo laparoscopic sphincter-saving resection for rectal cancer were enrolled in the present study. The learning curve was analyzed based on operative time using the moving average method. The cut-off point at which the mean operative time stabilized was defined as learning curve. The patients were divided into A (learning period) and B (experienced period) group. Data including the patients′ demographic characteristics, surgical characteristics, pathological results, postoperative complications were compared between the two groups.

The learning curve analysis for operative time using the moving average method showed stabilization at 80 cases, and the patients were divided into A (1-80 cases) and B group (81-208 cases). Patients had lower tumor distance from anal verge in group B than in group A (P<0.05). A significantly higher proportion of combined respiratory disease and inter sphincteric resection (ISR)were observed for patients in group B than they in group A (P<0.05). Both the operating time and blood loss were significantly lower in group B than they in group A. The rate of overall postoperative complications in group A had no significant difference compared with it in group B (P>0.05), but the rate of urinary retention was significantly lower in group B (P<0.05). There was no significant difference in the pathological results between the 2 groups, including number of harvested lymph nodes, ratio of positive circumferential margin, and ratio of affected distal margin.

Surgeons in the learning curve period of laparoscopic sphincter-saving resection for rectal cancer, could allow oncological safety, but they should pay attention to possibly high rate of postoperative urinary dysfunction.