Clinicopathological features of uterine sclerosing perivascular epithelioid cell tumor

LI Zhiwei; QIU Yuhan; JIAO Wanting; WEI Roufan; SUN Wu; ZHANG Wei

doi:10.3969/j.issn.1007-8096.2025.10.001

Abstract：Objective To investigate the clinicopathologic features,immunohistochemical profile,differential diagnosis,treatment,and prognosis of the uterine sclerosing perivascular epithelioid cell tumor(PEComa).Methods Clinical and pathological data of one case of uterine sclerosing PEComa were collected.The histological features and immunohistochemical staining patterns of the tumor on routine pathologic sections were observed,and relevant literature was reviewed.Results Microscopic examination revealed tumor cells arranged in nests,sheets,and trabeculae/cords.The tumor stroma exhibited marked hyalinization(>50%).Tumor cells were closely associated with blood vessels,arranged radially around thin-walled blood vessels.The tumor cells exhibited a bland epithelioid morphology with mild atypia,translucent cytoplasm(partially eosinophilic),and small nucleoli;nuclear pleomorphism was slight,and mitotic figures were rare(approximately 1/50 HPF).Immunohistochemistry showed the following staining patterns:HMB45 was focally positive;Melan-A showed partial positivity;TFE3,SMA,and Desmin were diffusely positive;and the Ki-67 proliferation index was approximately 2%in hot spots.Conclusion The uterine sclerosing PEComa is relatively rare,and its pathological morphology is easily confused with other female reproductive system tumors.The diagnosis of this histological subtype is facilitated by the presence of prominent stromal hyalinization,the characteristic perivascular growth pattern of tumor cells,and the co-expression of melanocytic and myogenic immunohistochemical markers.