Risk Stratification of Miscellaneous Uterine Mesenchymal Neoplasms: The Role of Morphology, Immunohistochemistry, and Molecular Testing

Uterine mesenchymal tumors are a diverse group of tumors that can display a broad range of morphologic, immunohistochemical, and molecular profiles and are associated with varied clinical behaviors. In recent years, they have increasingly been classified by their underlying molecular alterations, leading to a more precise separation of diagnostic entities. As their diagnostic criteria have been refined, so too have the features that can be used to predict clinical outcomes. This review includes a discussion of uterine inflammatory myofibroblastic tumors, perivascular epithelioid cell tumors (PEComa), and uterine tumors resembling ovarian sex cord tumors, with a focus on updates on their clinical behavior and tools for risk stratification to identify malignant tumors. In addition, we discuss the importance of using an integrated approach when classifying uterine mesenchymal tumors to improve diagnostic accuracy and guide clinical management.