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Perivascular epithelioid cell tumors (PEComas) are a family of tumors that includes angiomyolipoma (AML), clear-cell “sugar” tumor of the lung, lymphangioleiomyomatosis (LAM), clear cell myomelanocytic tumor of the falciform ligament, and rare clear cell tumors of other sites. They are composed of histologically, immunohistochemically, and ultrastructurally distinctive perivascular epithelioid cells. Bonetti et al. first proposed the origin of this family of tumors from perivascular epithelioid cells (PEC).[1] Histologically, these cells are epithelioid, or spindle-shaped with pale eosinophilic to clear cytoplasm and is intimately admixed with blood vessels. Usually, they co-express myomelanocytic markers. Among the melanocytic markers, human melanoma black 45 (HMB45) is more sensitive than Melan-A.[2] PECs can modulate their morphology and immunophenotype.[3] When the tumor is composed of epithelioid cells, it often expresses HMB45 more commonly than actin; when it is composed of predominantly spindle-shaped cells, then actin expression is more common. Ultrastructurally, these cells contain microfilament bundles with electron-dense condensation, numerous mitochondria, and membrane-bound granules.