Lymphadenectomy can be omitted for low-risk endometrial cancer based on preoperative assessments

Objective: According to the International Federation of Gynecology and Obstetrics staging, some surgeons perform lymphadenectomy in all patients with early stage endometrial cancer to enable the accurate staging. However, there are some risks to lymphadenectomy such as lower limb lymphedema. The aim of this study was to investigate whether preoperative assessment is useful to select the patients in whom lymphadenectomy can be safely omitted. Methods: We evaluated the risk of lymph node metastasis (LNM) using LNM score (histological grade, tumor volume measured in magnetic resonance imaging [MRI], and serum CA-125), myometrial invasion and extrautrerine spread assessed by MRI. Fiftysix patients of which LNM score was 0 and myometrial invasion was less than 50% were consecutively enrolled in the study in which a lymphadenectomy was initially intended not to perform. We analyzed several histological findings and investigated the recurrence rate and overall survival. Results: Fifty-one patients underwent surgery without lymphadenectomy. Five (8.9%) who had obvious myometrial invasion intraoperatively underwent systematic lymphadenectomy. One (1.8%) with endometrial cancer which was considered to arise from adenomyosis had para-aortic LNM. Negative predictive value of deep myometrial invasion was 96.4% (54/56). During the mean follow-up period of 55 months, one patient with deep myometrial invasion who refused an adjuvant therapy had tumor recurrence. The overall survival rate was 100% during the study period. Conclusion: This preoperative assessment is useful to select the early stage endometrial cancer patients without risk of LNM and to safely omit lymphadenectomy