Epitelioides

Epithelioides refers to a histological pattern characterized by cells that resemble epithelial cells. These cells are typically plump, polygonal, and have abundant eosinophilic cytoplasm, with vesicular or vesicular-appearing nuclei. This morphology is not specific to any single tissue type and can be observed in various benign and malignant conditions affecting different organs.

The term epithelioid is descriptive and implies a resemblance to epithelial cells in appearance, not necessarily in origin or function. Epithelioid cells can arise from a variety of cell types, including macrophages, lymphocytes, mesothelial cells, and even certain types of neoplastic cells. For example, epithelioid histiocytes are a common feature in granulomas, where they are thought to represent activated macrophages.

In pathology, the presence of epithelioid cells can be a significant diagnostic clue. Their arrangement and context within a tissue biopsy are crucial for determining the underlying cause. For instance, epithelioid cells found in the lung could suggest tuberculosis or sarcoidosis, while epithelioid patterns in the skin might indicate a specific type of inflammatory or neoplastic process. Tumors can also exhibit epithelioid morphology, such as epithelioid hemangioendothelioma or epithelioid leiomyosarcoma, where the neoplastic cells adopt this characteristic appearance. Accurate identification and interpretation of epithelioid cells require careful examination by a trained pathologist.