Low-grade osteosarcoma of metacarpal bone

A radiograph of the second left metacarpal bone in a 34-year-old man showed irregular lytic areas in the diaphysis that was expanded with perpendicular periosteal reactions. Examination of the first biopsy specimen indicated a fibrous dysplasia. Examination of the second biopsy specimen revealed an unequivocal grade I intramedullary osteosarcoma, desmoid to fibrous dysplasia-like in histological pattern. Three years after an adequate en bloc resection of the metacarpal bone, the man was healthy. The long-term course is usually favorable.