‘PET/CT is useful in finding small tumours in small children and is a promising imaging tool in evaluating paediatric malignancies,’ concludes Richard L Wahl MD, the ‘Henry N Wagner Jr. MD Professor of Nuclear Medicine’ at Johns Hopkins Medical Institutions in Baltimore, Maryland, who has pioneered the use of PET with FDG and fusion imaging in a wide range of common adult cancers. ‘In our study, we found that PET/CT can detect small lymph node lesions diagnosed as negative with conventional (or anatomical) imaging and deny the presence of active disease in soft-tissue masses post-treatment — especially in children with a wide range of malignant cancers. Using PET/CT could help spare children from overtreatment while fighting their disease.’
There are few findings about the use of PET/CT imaging compared with conventional imaging in paediatrics, he points out. The investigators retrospectively reviewed cases to evaluate the efficacy of PET/CT compared with other imaging methods. This involved 151 FDG PET/CT examinations performed on 55 children with non–central nervous system malignancies (30 had lymphoma).
PET with CT imaging — using the radio-tracer fluorodeoxyglucose (FDG) — enables collection of biological and anatomical information during just one examination — PET picks up metabolic signals of body cells and tissues; CT provides a detailed map of internal anatomy. ‘PET/CT showed its broad applicability and utility by providing additional information, in over a third of the children’s exams, that could be used by doctors to more appropriately manage or treat the disease in children,’ adds Dr Wahl. ‘When there were discrepancies between PET/CT and conventional anatomical imaging in analyzing cancer lesions, PET/CT was diagnostically accurate 90% of the time.’
Dr Wahl adds that additional studies with specific childhood cancers are warranted.
* Co-authors of ‘18F-FDG PET/CT in Evaluating Non-CNS Paediatric Malignancies’: Mitsuaki Tatsumi, of the Nuclear Medicine Division, and John H. Miller, Paediatric Radiology, both at the Radiology Department of the Johns Hopkins Medical Institutions, Baltimore, Md.