Angiolymphoid hyperplasia with eosinophilia in the skin

Angiolymphoid hyperplasia may present varied proliferative and inflammatory histologic patterns, which explains much of the previously confusing nomenclature. Ultrastructural and histochemical studies revealed the histiocytic qualities of the endothelial cell that constitutes much of the tumor. A similar transitional histiocytic endothelial cell with surrounding basal lamina, which contained massed cytoplasmic filaments suggestive of myofilaments, was observed alone or in groups. We believe that both the vascular and the histiocytic qualities of this cell population are characteristic and are helpful in diagnosis.