Differentiation between malignant and benign pathologic fractures with F-18-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography

Objective To evaluate the efficacy of F-18-fluoro-2-deoxy- D -glucose positron emission tomography/computed tomography (FDG PET/CT) in differentiating malignant from benign pathologic fractures. Materials and methods F-18 FDG PET/CT was performed on 34 patients with pathologic fractures between May 2004 and June 2007. Fractures were located in tubular bones (26), in the pelvis (six), in the spine (one) and in a rib (one). The FDG uptake pattern at the fracture site was described, whether FDG uptake occurred in the marrow or cortex and soft tissue. Maximum standardized uptake values (SUVmax, the largest value at the region of interest) were measured at the fracture site, including cortical bone, bone marrow and soft tissue. As a reference standard, biopsy was used for 12 patients and clinical follow-up for 22 patients. Sensitivity, specificity and diagnostic accuracy of PET/CT were calculated. Results There were 19 malignant and 15 benign fractures. In the malignant fractures, PET/CT demonstrated high (mean SUVmax 12.0, range 4.3 to 45.7) F-18 FDG uptake in bone marrow in most cases (17 of 19). In benign fractures, there was low FDG uptake (mean SUVmax 2.9, range 0.6 to 5.5) within cortical bone or adjacent soft tissue around the fracture, rarely in the marrow. There were significant differences in the pattern of intramedullary FDG uptake ( P