Introduction
Low-grade endometrial stromal sarcoma (LG-ESS) represents a unique challenge in gynecologic oncology. While it is the second most common malignant uterine mesenchymal tumor, it is frequently characterized by a clinical course that is significantly more indolent than the aggressive leiomyosarcoma. However, this perceived indolence can be deceptive. A notable subset of patients faces significant morbidity, late recurrences, and even mortality, yet clinicians have long struggled to identify which tumors will behave aggressively. Two landmark studies published in 2025 provide critical insights into the clinicopathologic features that drive prognosis and the efficacy of traditional adjuvant treatments.
