The Role of F-FDG-PET/CT in Pediatric Sarcoma.

Considerable debate remains regarding how best to incorporate F-FDG-PET/CT into clinical practice for pediatric sarcomas. Although there is a clear role for F-FDG-PET/CT in staging pediatric sarcoma, the value of F-FDG-PET/CT in prognostication for pediatric sarcomas remains unclear. In osteosarcoma, Ewing sarcoma, and rhabdomyosarcoma, F-FDG-PET/CT may be most useful in the identification of skeletal metastases, where the literature consistently suggests that it has improved sensitivity and specificity as compared to bone scintigraphy. The role of the imaging modality in the identification of pulmonary metastatic disease is less clear. Further controversy exists regarding the use of F-FDG-PET/CT in predicting outcome. Several studies, particularly in osteosarcoma, suggest changes in the maximal standardized uptake value (SUV) that can predict histologic response following neoadjuvant chemotherapy as well as overall outcome. Conversely, studies are conflicting regarding the use of F-FDG-PET/CT as a prognostic tool in Ewing sarcoma and rhabdomyosarcoma. The role of F-FDG-PET/CT in pediatric nonrhabdomyosarcoma soft tissue sarcomas is unknown at this time. Although most studies have been small and retrospective, in certain histologic subtypes, there is a clear role for the use of this imaging modality. Additional prospective and larger studies are needed to fully determine how best to incorporate F-FDG-PET/CT into treatment regimens for pediatric sarcomas in the future.