Navigating Diagnostic Challenges in Uterine PEComa: A Case Report and Mini Review of the literature

Perivascular epithelioid cell tumors (PEComas) represent rare mesenchymal neoplasms with dual myomelanocytic differentiation. We report a case of a uterine PEComa in a female patient presenting with chronic abnormal vaginal bleeding initially attributed to leiomyoma. The patient underwent abdominal excision of the leiomyoma, and gross examination revealed a well-circumscribed, ovoid mass measuring 6.3 cm. Histopathological evaluation showed a mesenchymal neoplasm with mild cytologic atypia, low mitotic activity (<1 per 50 high power fields), and no necrosis. Immunohistochemistry demonstrated positivity for smooth muscle markers (SMA, Desmin, Calponin, Caldesmon) and HMB-45, along with ER and PR, while Melan-A and other markers were negative. These findings support a diagnosis of uterine PEComa with uncertain malignant potential, as defined by Modified Specific Gynecologic Criteria and WHO 2020 guidelines. A literature review was conducted to elucidate the clinical, radiological, and pathological characteristics of uterine PEComas. Although many uterine PEComas are benign, features such as tumor size exceeding 5 cm and infiltrative growth may indicate a risk for aggressive behavior. Surgical resection remains the primary treatment for localized disease, while emerging targeted therapies, including mTOR inhibitors, show promise for advanced cases. This case highlights the diagnostic challenges of uterine PEComas, given their radiological resemblance to leiomyomas and other sarcomas, emphasizing the need for a multidisciplinary approach for accurate diagnosis and management.