EPITHELIOID

Resembling the appearance of an epithelium. In histopathology of the skin, the word is applied to histiocytes of inflammatory diseases, such as sarcoidosis, and melanocytes of noninflammatory processes, such as melanocytic nevi, in which cells with plump oval shape appear to touch one another like epithelial cells. Epithelioid histiocytes characterized by plump oval nuclei and abundant eosinophilic cytoplasm are disposed snugly in collections of sarcoidal and tuberculoid granulomas, in contrast to nonepithelioid macrophages, which tend to be disposed as solitary units. Epithelioid melanocytes, typified by plump oval nuclei and abundant eosinophilic cytoplasm, are seen, for example, in ovoid aggregations and fascicles in one of the numerous variants of Spitz's nevus.