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EP1111 Effectiveness of drainage following laparoscopic pelvic lymph node dissection

Introduction/Background Drainage, following pelvic lymph node (PLN) dissection for gynecological oncologic surgery to prevent postoperative lymphocyst formation and postoperative infection in pelvis, is controversial. The aim of this study is to elucidate the efficacy of drainage following PLN dissection especially in laparoscopic surgery. Methodology We evaluated 374 patients who underwent systemic PLN dissection at our institution between January 2012 and October 2018. The drainage tubes were placed in the retroperitoneal fossa in all patients. All tubes were removed a day after laparoscopic surgery. For those who underwent laparotomy, tubes were removed four days after operation until March 2016, and a day after operation in March 2016 or later. Clinical information such as drainage volume, lymphedema and lymphocysts were collected from medical records and analyzed retrospectively. Results 80 patients were treated by laparoscopy (Group A), while 294 patients were treated by laparotomy (Group B). No patients were re-operated due to postoperative hemorrhage. The median drainage volume a day after operation is 176.5 ml in Group A and 172 ml in Group B (P>0.05). Laparoscopy had significantly lower rates of lymphocysts (5% vs 16.7%, P<0.05), however incidence of lymphedema (5% vs 3%) and symptomatic lymphocysts (1.3% vs 3.4%) were similar between two groups. In laparotomy group, tubes were removed a day after operation (Group B1) in 172 patients, while tubes were removed four days after post operation (Group B2) in 122 patients. Between these two groups, there was no significant difference in incidence of lymphedema (3.5% vs 2.5%), lymphocysts (16.3% vs 17.2%) and symptomatic lymphocysts (1.3% vs 3.4%). Conclusion Our data suggests drainage has low importance both as an informative means and as an preventative means. Moreover, as incidence of lymphocyst was lower in laparoscopic group, drainage may not be necessary especially in laparoscopic surgery. Disclosure Nothing to disclose