Incomplete lymphatic sealing around the inferior mesenteric artery is a risk factor for chylous ascites in robotic rectal cancer surgery.

Abstract

Compared with laparoscopic surgery (LS), robotic surgery (RS) is considered to have acceptable outcomes in rectal cancer, but few reports have focused on chylous ascites in RS. The aim of this study was to investigate the incidence and etiology of chylous ascites after RS. This retrospective study included 291 patients with rectal cancer who underwent RS (n=165) or LS (n=126) with high ligation of the inferior mesenteric artery (IMA). Propensity score matching (PSM) was performed to compare the two groups. \Dissection around the IMA was achieved using ultrasonic coagulating shears in most LS cases, and monopolar scissors in most RS cases, sometimes using bipolar vessel sealing device or bipolar forceps. The incidence of chylous ascites was 12.2% in RS and 4.1% in LS after PSM (P=.037). When limited to the RS group, multivariate analysis identified absence of lymphatic sealing at the left side of the IMA and shorter operative time as independent risk factors for chylous ascites. Except for duration of drain placement, no outcomes differed significantly with or without chylous ascites. One patient with chylous ascites developed later infection and required antibiotic treatment. The incidence of chylous ascites is significantly higher in RS than in LS, and RS with incomplete lymphatic sealing around the IMA is a risk factor for chylous ascites in rectal cancer. Although outcomes for patients with chylous ascites were acceptable, adequate lymphatic sealing during dissection around the IMA is crucial to prevent chylous ascites in RS.