Introduction/Background The aim of this study is to evaluate the rate of low volume lymph node metastasis (LVM) diagnosed by sentinel lymph node (SLN) biopsy in order to establish treatment patterns and oncologic outcomes in patients with endometrial cancer.

Methodology We identified 126 patients who were treated surgically because of diagnosis of endometrial cancer between 2012–2017 in which sentinel lymph node biopsy was performed. We defined micrometastasis as a tumor present in a lymph node measuring >0,2 mm but <2,0 mm and isolated tumoral cels are those measuring ≤0,2 mm. Pathological study is performed by conventional hematosyline and eosin staining and ultrastaging by immunohistochemical analyses and OSNA technique is carried out.

Results 126 patients with a median age of 63 02±11,051 years. Histology is as follows: endometrioid 80,2%, serous 10,3%, carcinosarcoma 6,3%, clear cell 1,6%.

Concerning stage, 45,3% are low risk, 15,9% intermediate risk, 11,9% high-intermediate risk and 27% high risk. The rate of SLN detection is 100% by dual labeling with Tc99 and ICG.

105 cases (83,3%) of SLN are negative, 6 cases (4,8%) present macrometastasis, 7 cases (5,6%) micrometastasis and finally 3 cases (2,4%) ITC. 6 patients with micrometastasis receive Radiotherapy and the mayority of ITC patients receive adjuvant treatment. The overall survival (OS) is 93,5%and pathology free survival (PFS) is 87,5% in micro metastasis group, patients with ITC present a PFS of 66,7% with an OS of 100% finally patients with macrometastasis have a PFS of 90% with an OS of 80%.

Conclusion Patients with LVM frequently receive adjuvant treatment with improve of their oncological outcomes in comparison to those with macrometastasis. More prospective studies are necessary to define optimal adjuvant treatment in patients with LMV.

Disclosure Nothing to disclose.