Comparison of three different risk-stratification models for predicting lymph node involvement in endometrioid endometrial cancer clinically confined to the uterus

Objective: To compare the clinical validity of the Gynecologic Oncology Group-99 (GOG-99), the Mayo-modified and the European Society for Medical Oncology (ESMO)-modified criteria for predicting lymph node (LN) involvement in women with endometrioid endometrial cancer (EC) clinically confined to the uterus. Methods: A total of 625 consecutive women who underwent comprehensive surgical staging for endometrioid EC clinically confined to the uterus were divided into low- and high-risk groups according to the GOG-99, the Mayo-modified, and the ESMO-modified criteria. Lymphovascular space invasion is the cornerstone of risk stratification according to the ESMO-modified criteria. These 3 risk stratification models were compared in terms of predicting LN positivity. Results: Systematic LN dissection was achieved in all patients included in the study. LN involvement was detected in 70 (11.2%) patients. LN involvement was correctly estimated in 51 of 70 LN-positive patients according to the GOG-99 criteria (positive likelihood ratio [LR+], 3.3; negative likelihood ratio [LR-], 0.4), 64 of 70 LN-positive patients according to the ESMO-modified criteria (LR+, 2.5; LR-, 0.13) and 69 of the 70 LN-positive patients according to the Mayo-modified criteria (LR+, 2.2; LR-, 0.03). The area under curve of the Mayo-modified, the GOG-99 and the ESMO-modified criteria was 0.763, 0.753, and 0.780, respectively. Conclusion: The ESMO-modified classification seems to be the risk-stratification model that most accurately predicts LN involvement in endometrioid EC clinically confined to the uterus. However, the Mayo-modified classification may be an alternative model to achieve a precise balance between the desire to prevent over-treatment and the ability to diagnose LN involvement