Uterine Adenosarcoma: Unusual Presentations and Mimics

Uterine adenosarcoma is an uncommon biphasic neoplasm composed of malignant stroma and benign non-neoplastic epithelium. Most adenosarcomas show canonical low-grade morphology, which must be distinguished from various benign uterine polyps. A subset of adenosarcomas shows sarcomatous overgrowth, myometrial invasion, vascular invasion, heterologous differentiation, or marked nuclear atypia. These findings are prognostically adverse and may raise the differential with other uterine sarcomas. This article provides an overview of the clinicopathologic features of uterine adenosarcoma, with a particular focus on challenging presentations and histologic mimics.