Introduction/Background The incidence of lymph node metastasis in endometrial cancer is estimated at 3–9% in the low-risk group of patients to 20% in the high-risk group. Presence of metastases in lymph nodes is important prognostic factor for survival in patients with endometrial cancer and lymph node status is required for proper staging.

Methodology 192 patients who underwent laparoscopic hysterectomy due to endometrial cancer FIGO stage I and II were prospectively enrolled in sentinel node detection study. SNB were mapped with indocyanine green at the beginning of laparoscopic procedure. 421 sentinel lymph nodes in total were harvested. The lymph nodes were analyzed with standard Hematoxylin-Eosin staining and then with ultrastaging protocol with cytokeratin 19 to detect micrometastasis and isolated tumor cells (ITC).

Results Out of 192 patients, bilateral sentinel lymph nodes were found in 171 (89.1%) patients, while unilateral lymph nodes were found in 20 patients (10.4%). In 35 (18.2%) patients, a second sentinel was additionally harvested, including bilaterally in 11 patients, of which cancer metastasis was detected in only 3 patients. The most common location of the collected SNBs was bifurcation of the common iliac artery (30%), of which 10 (7.9%) SNBs were positive. The second most common localization was external iliac vessels (20.4%) with 6 (7%) positive nodes. Cancer metastases (macro and micrometastasis) were found in a total of 25 sampled nodes (5.9% of all patients). In case of 11 patients (2.6%) micrometastasis were detected only in ultrastaging causing upstaging. Finally, Isolated tumor cells were detected in 9 dissected lymph nodes.

Conclusion The most common location of SNB was bifurcation of the iliac artery and external iliac vessels. Ultrastaging is essential in detecting metastatic in SNB in endometrial cancer patients for the purpose of proper stating and further adjuvant treatment planning.

Disclosures None.