MICROSCOPIC DESCRIPTION: Sections show a multi-lobulated, circumscribed tumour with a fibrous pseudocapsule in areas. The tumour is moderately cellular composed of sheets of eosinophilic tumour cells set within extracellular matrix material. There are focal areas of haemorrhage and necrosis present. Tumour cells contain round-to-oval nuclei with finely granular chromatin and prominent nucleoli. Physalliferous cells containing vacuolated cytoplasm are present. No atypia or mitoses are seen. No skeletal muscle, lymphovascular or perineural invasion is seen. Margins are unable to be accurately assessed due to fragmentation.
DIAGNOSIS: Sacrum: Recurrent chordoma.