AUTHOR=Peng Shiyi , Zheng Ying , Yang Fan , Wang Kana , Chen Sijing , Wang Yawen TITLE=The Transumbilical Laparoendoscopic Single-Site Extraperitoneal Approach for Pelvic and Para-Aortic Lymphadenectomy: A Technique Note and Feasibility Study JOURNAL=Frontiers in Surgery VOLUME=Volume 9 - 2022 YEAR=2022 URL=https://www.frontiersin.org/journals/surgery/articles/10.3389/fsurg.2022.863078 DOI=10.3389/fsurg.2022.863078 ISSN=2296-875X ABSTRACT=Background:Nowadays, the lymphadenectomy could be performed by the transperitoneal or extraperitoneal approach. Nevertheless, each approach has its own advantages and disadvantages. For lymphadenectomy under these circumstances, we developed a transumbilical laparoendoscopic single-site (TU-LESS) extraperitoneal approach for lymphadenectomy. In this research, the primary goal is to demonstrate the feasibility of the novel approach in systematic lymphadenectomy and present the surgical process step-by-step. Methods: Between May in 2020 to June in 2021, patients who had the indications of systematic lymphadenectomy underwent lymphadenectomy via the TU-LESS extraperitoneal approach. This new approach was described in detail, and the clinical characteristics and surgical outcomes were collected and analyzed. Results: Eight patients with gynecological carcinoma were included in the research, including four with high-risk endometrial cancer and four with early-stage ovarian cancer. The TU-LESS extraperitoneal approach for pelvic and para-aortic lymphadenectomy was successfully performed in all patients without conversion. In all, a median of 26.5 pelvic lymph nodes (range 18 - 35) and 18.0 para-aortic lymph nodes (range 7 - 43) were retrieved. There was a median of 166.5 minutes of surgical time (range 123 - 205). Patients had speedy recoveries without complications. All patients had positive pain responses after surgery, as well as satisfactory cosmetic and body image outcomes. Conclusion: Our initial experience showed that it is feasible to perform systematic lymphadenectomy with the TU-LESS extraperitoneal approach. And this new approach may provide a new measure or a beneficial supplement for lymphadenectomy in gynecologic cancer.