[Radiculomedullary compressions by osteosarcoma and by giant cell tumor of the spine occurring in Paget's disease].

Two complications of Paget's disease are presented : they include an osteogenic sarcoma and a giant-cell tumour (GCT) of the lumbar spine with a radiculo-medullary compression syndrome. The rarity of sarcomatous degeneration of the spine affected by Paget's disease is emphasized and also the unusual character of the spinal GCT which develop in the presence of Paget's disease. As in the present case, it is often difficult to confirm the benign or malignant character of a GCT and the principal criteria of this classification are discussed.