MACROSCOPIC DESCRIPTION: mass has a smooth, greenish yellow capsule 1 mm in thickness that
appears complete. Fatty connective tissue lies over the capsule. The tumour is variegated black/brown/yellow and firm. There is a central cavity up to 60 mm in greatest diameter that is filled with reddish/brown friable fibrinous material.
MICROSCOPIC DESCRIPTION: Sections show an encapsulated cellular tumour. The tumour is composed of islands and nests of cells with a delicate interspersed capillary network. The cells are polygonal and have round to oval nuclei with smooth contours, finely stippled chromatin with occasional inconspicuous nuclei, and a large amount of finely granular cytoplasm. Pleomorphism is mild to marked, with scattered areas taking on a spindle cell morphology. Mitoses are rare or absent. Scattered intracytoplasmic and extracellular globular eosinophilic material is seen. Lakes of haemorrhage are seen scattered throughout the lesion but there is no necrosis. The tumour does not breach the capsule. The lesion is completely excised.