Hemangioma

Hemangioma is a generally benign tissue tumor resulted from endothelial cells proliferation and associated blood vessels. They can be internal, or form an external birthmark, which can be disfiguring especially if it forms on the face. They typically develop in the first few months of life, then involute or regress after several years. Internal hemangiomas, such as ones involving the airway, may be life-threatening.

Pathology

Microscopically, depending on the size of the vascular spaces, deliniated by tumor cells, hemangiomas may be capillary and cavernous. It is a non-encapsulated tumor, with an infiltrative, lobular growing.

Cavernous hemangioma: The tumor consists in large (cavernous) spaces, lined by tumor endothelial cells (which appear very similar to normal cells). These interconnected spaces are filled with blood and separated by a fibrous tissue. Photo: Atlas of Pathology