Benign lesions such as Paget's disease of the bone, enchondroma, osteochondromas, chronic osteomyelitis/infections and bone infarcts may rarely undergo malignant degeneration/transformation into sarcomas. To date, only 14 prior bone infarct-associated osteosarcomas have been described, with just two being primarily osteolytic. We discuss a case of a patient with a humeral bone-infarct, who presented with a presumed benign pathological fracture of the humerus through the bone infarct. Subsequent imaging and biopsy showed that there was a malignant degeneration into a primarily osteolytic osteosarcoma. We review the patient's presentation, radiographic and histologic appearance of the osteosarcoma and discuss the epidemiology, surgical and non-surgical treatment and surveillance of bone-infarct-associated osteosarcomas.
Keywords: bone infarct; osteosarcoma; pathological fracture; sarcoma.