Cytological features of bone tumours in FNA smears II: cartilaginous tumours.

Chondromas are benign tumours of hyaline cartilage. The enchondromas are tumours of the medullary bone while periosteal (juxtacortical) chondromas arise from the periosteum. Enchondromas are common bone tumours with a wide age distribution, although the majority of patients are 20–40 years of age. Almost 50% of surgically removed enchondromas occur in the small bones of the hands and feet. The second commonest sites are the proximal part of the humerus and the proximal and distal femur. Enchondromas of the hands and feet are typically palpable and sometimes painful tumours. However, these tumours are commonly first discovered when a mild to moderate trauma causes a fracture. Multiple enchondromas are designated as enchondromatosis or Ollier’s disease. Periosteal chondromas are less common than enchondromas and are most common in the long bones.