Littoral Cell Angioma: A Morphologic and Immunohistochemical Study

  Littoral cell angioma is a splenic vascular tumor of splenic sinus lining cells that is considered benign in general. This report describes a case of littoral cell angioma with no malignant histological features. The lesion is composed of anastomosing vascular channels resembling splenic sinus; they are lined by endothelial cells which show mitotic activity very rare. Immunohistochemically, the tumor cells were positive for both endothelial (Factor VIII-AG, CD34) and histiocytic markers (KP1 or CD68). The morphologic and immunohistochemical findings in this tumor confirm the presence of dual (endothelial / histiocytic) characteristics of the reticuloendothelial cells lining the splenic sinus, justifying the term littoral cell angioma.