Imaging primary musculoskeletal tumors: role of18F-FDG-PET/CT

Sarcomas are rare and represent approximately 1% of malignant tumors. Symptoms may be pain, palpable mass or pathologic fractures. Early diagnosis of sarcomas is essential, because prognosis and therapeutic options are much better in lower tumor stages than in higher tumor stages. However, the diagnosis of soft-tissue sarcomas or bone sarcomas is often delayed owing to the lack of specific clinical symptoms and misinterpretation of radiological findings. Optimal management of sarcomas depends on the site, grade and accurate staging of the tumor when first diagnosed. The metastatic spread of sarcomas is mainly hematogenous to the lungs, although lymphatic spread may occur. Traditional diagnostic imaging methods for the evaluation of musculoskeletal tumors include ultrasound, CT, MRI and bone scintigraphy. PET and PET/CT is a relatively new imaging technique that enables in vivo characterization of tumor metabolism. 18F-2-deoxy-2-fluoro-glucose (FDG) is the ‘work horse’ tracer of tumor imaging with PET. Bro...