The purpose of this study was to clarify the clinical behaviour, prognosis, and optimum treatment of dedifferentiated low-grade osteosarcoma (DLOS) diagnosed based on molecular pathology. We retrospectively reviewed 13 DLOS patients (six men, seven women; median age 32 years (interquartile range (IQR) 27 to 38)) diagnosed using the following criteria: the histological coexistence of low-grade and high-grade osteosarcoma components in the lesion, and positive immunohistochemistry of mouse double minute 2 homolog (MDM2) and cyclin-dependent kinase 4 (CDK4) associated with MDM2 amplification. These patients were then compared with 51 age-matched consecutive conventional osteosarcoma (COS) patients (33 men, 18 women; median age 25 years (IQR 20 to 38)) regarding their clinicopathological features.Aims
Patients and Methods
A case is reported four years after successful total replacement of the left humerus for chronic osteomyelitis of six years' duration, with an axillary sinus that had persisted despite repeated operations and more distally a pathological fracture that had failed to united after bone grafting. The disability was such that the patient had requested amputation, but he returned to his previous work as a driver six months after the total replacement and there has been no recurrence of infection.