(A): Low-magnification image (×1.25) shows proliferation of capillary-sized vessels in a lobular arrangement. Larger dilated vessels are observed at the base of the stalk (inset). (B): Surface is eroded (×4). (C): Anastomosing small blood vessels are lined with plump endothelial cells. The stroma is edematous with mild infiltration of mononuclear cells and neutrophils (×200). (D) Mitoses are occasionally seen in the endothelial cells (×400).