CHONDROBLASTIC OSTEOSARCOMA - CHARACTERIZATION BY GADOLINIUM-ENHANCEDMR-IMAGING CORRELATED WITH HISTOPATHOLOGY

Objective. To identify specific features of chondroblastic osteosarcom a on gadopentetate dimeglumine (Gd)-enhanced magnetic resonance (MR) i maging. Design and patients. Nine patients with chondroblastic osteosa rcoma and a control group of 20 patients with conventional central ost eosarcoma were included in this study. The histopathological findings of the surgical specimens were compared with enhancement patterns on s tatic Gd-enhanced MR images. Results. In chondroblastic osteosarcoma s eptonodular and peripheral rim enhancement represented tumour with a p ure chondroid matrix. Non-enhancing and heterogeneous enhancing areas represented tumour with both chondroid and osteoid matrix. In the tumo urs in the control group enhancement was predominantly heterogeneous b ut in one it was homogeneous. All these areas corresponded to necrotic or viable osteoid tumour tissue or fibrovascular tissue in areas of n ecrosis. Conclusion. Gd-enhanced MR imaging can assist in obtaining di agnostic biopsy material of chondroblastic osteosarcoma by identifying both osteoid-and chondroid-forming areas.