Cutaneous “fibroma‐like” perivascular epithelioid cell tumor: A case report and review of literature

摘要

Abstract Perivascular epithelioid cell tumors (PEComas) are a group of lesions sharing the common features of co‐expression of melanocytic and myogenic markers, with focal association of the cells with vascular walls. The PEComa group exhibits a wide range of morphologies. A “fibroma‐like” variant of PEComa has been recently described. The case reported herein is that of an infant with tuberous sclerosis complex (TSC) presenting with a lip mass. Excisional biopsy showed a moderately cellular tumor composed of spindled to stellate cells embedded within a collagenized stroma. The cells showed focal perivascular accumulation and positivity for both melanocytic (HMB‐45) and myogenic (desmin) markers. This is the fifth reported case of “fibroma‐like” PEComa in literature and the youngest patient to date. All of the “fibroma‐like” PEComas were found in patients with tuberous sclerosis—hence, the diagnosis of this entity should prompt a workup for TSC; conversely, a fibroma‐like lesion in a patient with TSC or with TSC‐related conditions should be evaluated using melanocytic and myogenic markers. Melanocytic and myogenic markers are also useful in differentiating “fibroma‐like” PEComa from other differential diagnoses such as fibroma and benign fibrous histiocytoma.