Fluorodeoxyglucose positron emission tomography of soft tissue tumours: Is a non-invasive determination of biological activity possible?

Since musculoskeletal tumours comprise a large heterogeneous group of entities with different biological behaviour, clinical diagnosis of such lesions can be very difficult. The aim of this prospective study was to assess the usefulness of 2-[F-18]-fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) in the non-invasive evaluation of soft tissue tumours. One hundred and two patients with suspected soft tissue neoplasms were investigated by FDG-PET. The uptake of FDG was evaluated semiquantitatively by determining the tumour to background ratio (TBR). All patients underwent biopsy, resulting in the histological detection of 39 high-grade sarcomas, 16 intermediate-grade sarcomas, 11 low-grade sarcomas, 25 benign tumours, 10 tumour-like lesions such as spontaneous myositis ossificans (n = 6) and one non-Hodgkin lymphoma. All lesions except for two lipomas disclosed an increased FDG uptake. Sarcomas showed significantly higher TBR values than latent or active benign lesions (P