Imaging for the Diagnosis and Monitoring of Osteosarcoma

Summary: Osteosarcoma is the most common primary malignant bone tumour. The aim of this study is to illustrate the contribution of imaging to diagnosis, extension assessment and therapeutic follow-up. Thirty cases were collected in the radiology department, including 10 men and 5 women. The average age was 25 years. The preferred site was the lower extremity of the femur. Standard radiology and CT scans were performed in all patients, and eleven patients underwent MRI. Standard radiography showed poorly limited geographic osteolysis with periosteal reaction, cortical rupture and soft tissue invasion in 8 cases, mitted osteolysis in 4 cases and permeative osteolysis in 1 case. CT revealed osteolysis with cortical rupture and soft tissue invasion in all 12 cases. MRI showed an osteolytic process with T1 hypersignal, T2 hypersignal and contrast with cortical rupture and soft tissue invasion in 11 cases, with skip metastases in 1 case and intra-articular effusion in 2 cases. All patients were evaluated for metastases. Histological confirmation was obtained by biopsy. Although simple films can be used to diagnose malignant tumours, MRI remains the preferred technique for assessing locoregional extension, prognosis, tumour response to induction chemotherapy and long-term monitoring.