Clinical Significance of Sentinel Lymph Node Dissection in Preoperative Endometrial Intraepithelial Neoplasia: A Single-Institution Analysis

Abstract Objectives Endometrial intraepithelial neoplasia (EIN) carries a notable risk of concurrent endometrial carcinoma, yet the role of routine lymphadenectomy remains uncertain. This study evaluated the role, safety, and outcomes of sentinel lymph node dissection (SLNd) in patients with preoperative EIN, aiming to identify those with occult carcinoma or nodal metastases who may benefit from adjuvant therapy. Methods This retrospective cohort study included patients with EIN who underwent hysterectomy with or without SLNd at two university hospitals between February 2017 and December 2021. The primary outcome was the rate of lymph node metastasis in the SLNd group; secondary outcomes included SLN mapping success, detection of carcinoma on final pathology, SLNd-associated morbidity, and adjuvant treatment requirements. Results Among 107 patients, 86 (80.4%) underwent SLNd or complete lymphadenectomy, and 21 (19.6%) had hysterectomy alone. SLN mapping was successful in 90.7% of patients, with bilateral mapping in 69.8%. Endometrial carcinoma was identified in 48% of SLNd patients versus 15% of those undergoing hysterectomy alone. Nodal metastasis occurred in 1 of 78 patients (1.2%), consisting solely of isolated tumour cells. No complications were directly attributable to SLNd no significant differences in hospital length stay, blood loss, operative time, or overall complication rates. Adjuvant therapy was required in 7 patients (8.1%) undergoing SLND. Conclusion In this cohort, SLNd demonstrated a favorable safety profile and high detection rates; however, the overall incidence of nodal metastasis was low (1.2%). These findings support a selective rather than routine lymph node evaluation strategy in this population. Furthermore, identification of positive sentinel lymph nodes did not lead to changes in clinical management, indicating a limited impact on therapeutic decision-making for patients with otherwise low-risk disease.