Bone tumor pathology.

Although the skeletal system is a common site of involvement by metastatic carcinoma as well as myeloma and lymphoma, primary tumours of bone are rare, accounting for only 0.2% of all neoplasms. Primary bone tumours are, however, an important cause of disability and death, especially in the young. Tumours are classified according to both biological behaviour and histological subtype. Tumours may be broadly grouped as benign, locally aggressive or malignant. Histologically, they are grouped according to the form of differentiation they show, for example bone forming or cartilage forming. Most tumours show some degree of age and site predilection, and knowledge of this assists in diagnosis. This review discusses the pathology of bone tumours as well as the group of tumour-like lesions that affect the skeleton. In view of their rarity, diagnosis and management of bone tumours is best achieved in regional centres. Orthopaedic surgeons, radiologists and pathologists must work closely together to ensure accurate diagnosis and thereby prevent over- and under-treatment.