Paget's disease of the skull with osteosarcoma and neurological symptoms associated.

Paget's disease is a common entity but osteosarcoma arising in Paget's disease is an infrequent complication. Primary osteosarcomas are typically long bone tumours and the skull is rarely affected. A case with malignant transformation of Paget's disease of the skull and an unusual clinical presentation is reported. Computed tomography scans of the tumour area show interesting results. Main features are: an intensive sclerotic reaction of the host bone, an inner and outer spiculation of the calvarium, radial ossifications in the soft extracranial mass, and spotty calcifications and ossifications of the osteosarcomatous portion infiltrating the brain.