(A) A macroscopic image of the composite paraganglioma. The well delineated cranial part (right side) of the tumor with cysts, necrosis and hemorrhages represents the paraganglioma. The less well demarcated, white-gray-tan colored solid part of the tumor (left side) represents the caudally located neuroblastoma component. (B) The microscopic image demonstrates the two histological components of the tumor delineated by fibrous tissue. The paraganglioma (upper part) appears lighter in the low power view corresponding to more abundant cytoplasm of the tumor cells that are arranged in the typical Zellballen pattern (inlet A). The neuroblastoma (lower part) appears bluish corresponding to the densely packed small blue round cells with scant cytoplasm (inlet B). In the fibrous band between both components the vascular invasion of the neuroblastoma can be appreciated.