Primary cutaneous perivascular epithelioid cell tumor: A clinicopathological and molecular reappraisal

pcPEComas have a different molecular signature than extracutaneous tumors and are unrelated to tuberous sclerosis. However, the common expression of 4E-binding protein 1 points to a role of the mTOR pathway in their pathogenesis. Because pcPEComas are diagnostically challenging, we propose that micro-ophthalmia-associated transcription factor, NKIC3, smooth muscle actin, desmin, bcl-1, cathepsin K, and 4E-binding protein 1 can be used when evaluating a possible pcPEComa.