Image Description
Solitary fibrous tumor of kidney: The tumor is composed of spindle cells arranged haphazardly or in intersecting bundles. There may be alternating areas of hypo- and hypercellularity. The stroma contains thick bands of hyalinized collagen as well as staghorn blood vessels (hemangiopericytoma-like). The tumor cells have scant cytoplasm and elongated wavy nuclei with little atypia or mitotic activity.