Bone tumour. Coloured magnetic resonance imaging (MRI) scan of the knee of a female patient with a tumour (pink) in the thigh bone (femur). The shin bone (tibia) is at bottom. This type of tumour can be malignant (cancerous) or benign (non-cancerous). Examples of malignant bone tumours include osteosarcoma, chondrosarcoma and Ewing's sarcoma. Benign bone tumours include osteoma, osteochondroma and fibrous dysplasia. Sometimes, the tumour is a secondary bone tumour, where cancerous tumours have metastasised (spread) to the bone from elsewhere in the body. Treatment depends on the type of tumour, but usually includes surgery to remove the affected bone (such as amputation in severe cases), radiotherapy and chemotherapy.