Uterine Stroma-Derived Tumors and the Extracellular Matrix: A Comparative Review of Benign and Malignant Pathologies.

Uterine stromal-derived tumors encompass a spectrum of rare neoplasms, ranging from benign endometrial stromal nodules to aggressive high-grade endometrial stromal sarcomas and undifferentiated uterine sarcomas. The classification of these tumors has advanced through molecular and immunohistochemical profiling, but the role of the extracellular matrix (ECM) in their biology is only beginning to be understood. The ECM provides both structural support and dynamic signaling cues, regulating tumor cell proliferation, invasion, angiogenesis, and immune evasion. Altered expression of collagens, proteoglycans, glycosaminoglycans, and matricellular proteins reshapes stromal architecture and contributes to disease progression. Moreover, ECM remodeling enzymes such as matrix metalloproteinases, together with cross-linking factors, create a stiff and pro-tumorigenic microenvironment that facilitates invasion and therapeutic resistance. Furthermore, these matrix alterations intersect with angiogenesis, mechanotransduction pathways, and immune modulation. Studies to date describe the role of ECM molecules in the function of the physiological uterine tissue and data for the uterine stroma-derived tumors is scarce. This review summarizes the existing knowledge in classification, prognosis and diagnosis, and summarizes the ECM-driven mechanisms in tumors described so far, aiming to identify new and prognostic biomarkers and novel therapeutic targets in uterine sarcomas.