To analyze the learning curve of fascia space priority approach laparoscopic lateral lymph node dissection in rectal cancer by a retrospective study.

The clinical data of 108 patients who had fascia space priority approach laparoscopic lateral lymph node dissection in the initial stage in Tianjin Union Medical Center from June 2017 to April 2022 were collected. CUSUM curve analysis was performed on the operative time and intraoperative blood loss, so as to obtain the learning curve of the technique. The cut-off value was determined by the learning curve and then group analysis was taken.

A total of 108 patients were included. The cut-off value of operation time and intraoperative blood loss was 30 cases analyzed by CUSUM curve, including 12 cases with bilateral dissection, so a total of 42 unilateral lateral node dissection were performed. The 108 patients were divided into 3 groups, including 30 cases in the learning improvement stage, thirty cases and 48 cases in the proficiency stage. There were no statistically significant differences in baseline level and pathological condition among the three groups, while there were statistically significant differences in operative time and intraoperative bleeding. Learning time in the learning improvement stage was significantly higher than that in the proficiency stage (442.7 min vs. 356.5 min, 428.4 min, F=10.768, P＜0.01). Intraoperative blood loss in the learning improvement stage was significantly higher than that in the proficiency stage (200 mL vs. 150 mL, 150 mL, H=8.839,P=0.012).

In order to enter proficiency stage, thirty cases (42 unilateral) of fascia space priority approach laparoscopic lateral lymph node dissection are necessary, that means it can be considered to have passed the learning curve and mastered the technique after 30 cases (42 unilateral) of this procedure conducted.