Spleen, Littoral cell angioma

Littoral cell angioma is a relatively uncommon, benign, primary vascular lesion of the spleen. Grossly, it is characterized by multiple spongy, cystic nodules. Microscopically, the cystic spaces are composed of anastomosing vascular spaces of varying diameter, lined by cuboidal to tall cells with occasional papillary structures. The lumina often contain abundant exfoliated cells. There is typically no cytological atypia, necrosis, or mitoses. By immunohistochemistry, they tend to show a histiocytic and endothelial immunophenotype, being positive for both CD31/Factor VIII and CD68. CD34 is typically negative.