To review and compare clinical manifestations of and risk factors for anastomotic leakage (AL) after low anterior resection for rectal cancer between minimally invasive surgery (MIS) and open surgery (OS). MIS for rectal cancer has become popular, and its clinical course is different from OS. Many studies have reported on the risk factors and oncologic influence of AL. However, few have directly compared clinical manifestations and risk factors for AL between MIS and OS. From January 2004 to December 2012, a total of 1704 consecutive patients who underwent elective low anterior resection with colorectal anastomosis for rectal cancer were eligible. The variables associated with short-term outcomes and risk factors were analyzed. The overall AL incidence was 6.4%. In the MIS-AL group, the time to diagnosis of AL and the time to second operation were shorter. A majority of the patients (77.8%) in the MIS-AL group underwent second MIS operation, whereas none in the OS-AL group. The hospital stays after second MIS were shorter than those after second open operation. Multivariate analyses revealed that male sex, smoking and alcohol intake history, previous abdominal surgery, longer operation times, low-lying tumor, and using 2 or more staplers for distal rectal resection were independent risk factors in the MIS-AL group, whereas smoking and alcohol intake history, operation times, and blood loss were significant in the OS-AL group. The clinical manifestations of and risk factors for AL were different between MIS and OS. AL after MIS may be more influenced by factors related to technical difficulties. Close attention should be given to patients undergoing surgery with risk factors for AL.

As robotic surgery was developed with ergonomic designs, there are expectations that the technical advantages of robotic surgery can shorten the learning curve. However, there is no comparative study, so far, to evaluate the learning curve between robotic and laparoscopic rectal cancer surgeries. Therefore, the aim of this study is to compare the learning curve of robotic low anterior resection (LAR) with laparoscopic LAR for rectal cancer.Patients who underwent robotic or laparoscopic LAR by a single surgeon were compared retrospectively (robot n = 89 vs laparoscopy n = 89). Cumulative sum (CUSUM) was used to evaluate the learning curve. The patients were divided into phase 1 (initial learning curve period) and phase 2 (post-learning curve period). The perioperative clinicopathologic characteristics were compared by phases and surgical procedures.According to CUSUM, the learning curve of robotic LAR was the 44th case and laparoscopic LAR was the 41st case. The learning phases were divided as follows: phase 1 (cases 1-41) versus phase 2 (cases 42-89) in the laparoscopic group, and phase 1 (cases 1-44) versus phase 2 (cases 45-89) in the robotic group. Comparison between phase 1 and phase 2 in each type of surgery showed no significant difference for the perioperative outcomes. Comparison between robotic and laparoscopic surgeries in each phase showed similar perioperative results. Pathologic outcomes were not significantly different in both procedures and phases.The learning curve of robotic LAR for rectal cancer was similar to laparoscopic LAR, and the clinicopathologic outcomes were similar in both the procedures.

Although the total cost of robotic surgery (RS) is known to be higher than that of laparoscopic surgery (LS), the cost-effectiveness of RS has not yet been verified. The aim of the study is to clarify the cost-effectiveness of RS compared with LS for rectal cancer.From January 2007 through December 2011, 311 and 560 patients underwent totally RS and conventional LS for rectal cancer, respectively. A propensity score-matching analysis was performed with a ratio of 1:1 to reduce the possibility of selection bias. Costs and perioperative short-term outcomes in both the groups were compared. Additional costs due to readmission were also analyzed.The characteristics of the patients were not different between the 2 groups. Most perioperative outcomes were not different between the groups except for the operation time. Complications within 30 days of surgery were not significantly different. Total hospital charges and patients' bill were higher in RS than in LS. The total hospital charges for patients who recovered with or without complications were higher in RS than in LS, although their short-term outcomes were similar. In patients with complications, the postoperative course after RS appeared to be milder than that of LS. Total hospital charges for patients who were readmitted due to complications were similar between the groups.RS showed similar short-term outcomes with higher costs than LS. Therefore, cost-effectiveness focusing on short-term perioperative outcomes of RS was not demonstrated.

Compared with conventional laparoscopic surgery, single-incision laparoscopic surgery produces better cosmetic benefits. The aim of this study was to investigate the learning curve for single-incision laparoscopic anterior resection (SILAR) for sigmoid colon cancer using multidimensional methods. From September 2009 through May 2014, one hundred and thirteen patients underwent SILAR for sigmoid colon cancer by a single surgeon at Severance Hospital. The learning curve was analyzed using moving average, cumulative sum control chart (CUSUM), and risk-adjusted CUSUM methods. For risk-adjusted CUSUM, surgical failure was defined as conversion to open surgery or conventional laparoscopic surgery, morbidity within 30 days after surgery, <12 harvested lymph nodes, or local recurrence. Using the moving average method, the peak point for operation time occurred at the 65(th) case (173 minutes). The CUSUM method also showed the operation time peak point at the 65(th) case. However, the risk-adjusted CUSUM curve did not ascend after the 61st case. The operation time and hospital stay for the 60 phase 1 patients (cases 1 to 60) were longer than for 53 phase 2 patients (cases 61 to 113) (166.6 vs 140 minutes; p < 0.001 and 7.1 vs 5.5 days; p = 0.009). Phase 2 patients had a significantly larger tumor diameter and more harvested lymph nodes. The learning curve for SILAR for sigmoid colon cancer was 61 to 65 cases according to multidimensional statistical analyses. Single-incision laparoscopic anterior resection is feasible for surgeons experienced in laparoscopic surgery. However, SILAR required more cases for proficiency than the number previously reported for conventional laparoscopic surgery, likely because of its technical challenges.