Introduction/Background There is limited consensus on the optimal management approach for patients experiencing mapping failure in endometrial cancer (EC). Understanding the risk factors that contribute to sentinel lymph node(SLN) metastasis is of paramount importance. This manuscript aims to provide a comprehensive analysis of the risk factors associated with SLN metastasis.

Methodology A total of 874 women with EC were included in this retrospective study. Out of the initial cohort of 874 patients, a total of 793 patients with successful SLN mapping were included and analysed to investigate the risk factors for SLN metastasis in EC.

Results SLN metastasis was detected in 73 (9.2%) patients. Among the metastatic cases, 20 (27.4%) patients had isolated tumour cells (ITC), 17 (23.3%) patients had micrometastasis, and 36 (49.3%) patients had macrometastasis in the sentinel lymph nodes. The results of the univariate analysis demonstrated a significant association between SLN metastasis and several factors, including age over 60 years, histology other than endometrioid, tumor grade 3, deep myometrial invasion, lymphovascular space invasion (LVSI), primary tumour diameter of 2 cm or larger, and cervical stromal invasion (p < 0.05). At the end of multivariate analysis, deep myometrial invasion [odds ratio (OR), 2.42; 95% confidence interval (CI), 1.29–4.56; p = 0.006], LVSI (OR, 7.27; 95% CI, 3.82–13.81; p < 0.001) and cervical stromal invasion (OR, 2.18; 95% CI, 1.13–4.21; p = 0.020) remained as independent risk factors for SLN involvement in women with EC.

Conclusion LVSI, deep myometrial invasion, and cervical stromal invasion emerged as independent risk factors for SLN metastasis in patients diagnosed with EC. In cases where the identified risk factors are absent, the omission of lymphadenectomy may be considered in instances of SLN mapping failure.

Disclosures The authors has no competing financial interests or conflicts of interest to disclose.