552 Dual cervical and fundal injection in endometrial cancer

Abstract

<h3>Introduction/Background</h3> Sentinel node in endometrial cancer (EC) is an evolving technique to know the nodal status in a more precise way without the need to perform a complete lymphadenecotomy. The aim of this study was to describe our latest results using dual cervical and fundal indocyanine green (ICG) injection for detection of sentinel lymph node (SLN) in endometrial cancer and results of SLN biopsy. <h3>Methodology</h3> This is an observational prospective study performed between 26 June 2014 and 31 December 2019, 278 patients underwent laparoscopic surgery for endometrial cancer at Hospital Uniersitario Donostia, in Spain. In all cases, we performed SLN biopsy with dual cervical and fundal ICG injection, looking for pelvic and aortic sentinel node. All SLNs were processed with an ultrastaging technique. A total of 128 patients with Intermediate and High risk EC also underwent total pelvic and paraaortic lymphadenectomy. <h3>Results</h3> The detection rates were as follows: 93.52% (260/278) overall for SLNs; 90.65% (252/278) overall for pelvic SLNs; 67.99% (189/278) for bilateral SLNs; 66.91% (186/278) for paraaortic SLNs, and 2.88% (8/278) for isolated paraaortic SLNs. We found macroscopic lymph node metastasis in 26 patients (10.03%) and microdisease in lymph nodes in another 48 patients, raising the overall rate of lymph node involvement to 16.19%. There was one false negative (negative SLN biopsy but positive lymphadenectomy). 6.6% of all pelvic and also aortic sentinel nodes were positive for metastasis. Applying the SN algorithm, the sensitivity of detection was 97.9% (95% CI 89.1–99.6), specificity 100% (95% CI 98.2–100), negative predictive value 99.5% (95% CI 97.4–99.9), and positive predictive value 100% (95% CI 92.4–100). <h3>Conclusion</h3> Dual sentinel node injection is a feasible technique that achieves adequate detection rates. Additionally, this technique allows a high rate of aortic detection, identifying a non-negligible percentage of isolated aortic metastases. Aortic metastases in endometrial cancer are possible and it is necessary to investigate the relevance of its detection. <h3>Disclosures</h3> No disclosures.