Postoperative radiotherapy in perivascular epithelioid cell tumors (PEComas): A narrative review

Perivascular epithelioid cell tumor (PEComa), which is relatively new to the literature, is a rare mesenchymal tumor containing perivascular epithelioid cells. The immunohistochemical features of the disease must be considered for diagnosis. The disease contains melanocytic differentiation markers such as HMB45 and MelanA/Mart1, and myogenic markers such as actin, but does not express markers such as epithelial membrane antigen, keratin, or S-100. The disease can be seen in almost every organ. Most PEComas are benign. Malignant PEComa can follow an aggressive course, capable of recurrence and metastasis. The primary treatment approach for localized disease is surgical resection. Adjuvant systemic therapy can be administered to high-risk patients. It is noteworthy that the literature on postoperative radiotherapy in PEComa is limited with studies focusing primarily on gynecological cases. Most of the patients remained disease-free during follow-up, suggesting radiotherapy may be effective for local control. Integration of molecular profiling and mTOR-targeted approaches alongside radiotherapy may further define optimal management strategies.