Utility of positron emission tomography in sarcomas

Positron emission tomography using [18F]fluoro-2-deoxy-D-glucose has been studied as a tool to help predict the malignant potential of sarcomas, prognosis of patients and response to chemotherapy, and to detect disease recurrence. Recent developments in the use of [18F]fluoro-2-deoxy-D-glucose positron emission tomography in the clinical management of patients with suspected or diagnosed sarcomas are presented.

[18F]fluoro-2-deoxy-D-glucose positron emission tomography should not be used in lieu of histology to diagnose sarcomas, but may aid in biopsy planning. [18F]fluoro-2-deoxy-D-glucose positron emission tomography should not replace magnetic resonance imaging and computed tomography imaging for staging or surveillance. In soft tissue sarcomas, [18F]fluoro-2-deoxy-D-glucose uptake correlates with histologic grade and risk of tumor recurrence. Reduction in [18F]fluoro-2-deoxy-D-glucose uptake is an early predictor of histologic response of osteosarcoma, Ewing's and soft tissue sarcomas to chemotherapy, and has correlated with clinical outcomes in Ewing's, soft tissue sarcomas and gastrointestinal stromal tumor.

[18F]fluoro-2-deoxy-D-glucose positron emission tomography will likely play increasingly important prognostic and predictive roles in the management of sarcomas. Available data suggest that positron emission tomography is useful clinically in predicting response to therapy early in the course of treatment for both cytotoxic chemotherapy and kinase inhibitors. Additional study to determine the optimal semiquantitative measure of [18F]fluoro-2-deoxy-D-glucose accumulation in sarcoma and standardization of positron emission tomography methods is needed.