Cellular angiomas of infancy: an ultrastructural study of two cases

Vascular tumors in infants may be clinically disfiguring, requiring surgical intervention. Some of these lesions are histopathologically worrisome, due to increased cellularity and mitotic activity. The interpretation of these lesions is hampered by a surfeit of terminology, although, regardless of the diagnostic name, they are clinically benign. Two such cellular angiomas are reported, one typical and one unusual case. Electron microscopy of both cases demonstrated a heterogeneous cellular composition, primarily endothelial cells and pericytes. In those light microscopic areas of diffuse growth, primitive vascular structures were resolved. Electron microscopy may be diagnostically useful in supporting the light microscopic impression of a vascular tumor.