The incremental value of 18F-FDG PET/CT in paediatric malignancies.
OBJECTIVE
(18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET) imaging has been used in the assessment of paediatric malignancies. PET/CT increases the diagnostic accuracy in adult cancer patients. The present study assesses the incremental value of FDG PET/CT in paediatric malignancies.


METHODS
A total of 118 (18)FDG PET/CT studies of 46 paediatric patients were reviewed retrospectively. PET and PET/CT results were classified as malignant, equivocal or benign, compared on a site- and study-based analysis, and also compared with the clinical outcome.


RESULTS
Three hundred and twenty-four sites of increased FDG uptake were detected. Discordant PET and PET/CT interpretations were found in 97 sites (30%) in 27 studies (22%). PET yielded a statistically significant higher proportion of equivocal and a lower proportion of benign lesion and study results (p<0.001) than PET/CT. With PET there were 153 benign (47%), 84 (26%) equivocal and 87 (27%) malignant sites, while PET/CT detected 226 benign (70%), 10 (3%) equivocal and 88 (27%) malignant lesions. PET/CT mainly improved the characterisation of uptake in brown fat (39%), bowel (17%), muscle (8%) and thymus (7%). The study-based analysis showed that 17 equivocal and seven positive PET studies (20%) were interpreted as benign on PET/CT, while three equivocal studies were interpreted as malignant. The study-based sensitivity and specificity of PET/CT were 92% and 78% respectively.


CONCLUSIONS
PET/CT significantly improved the characterisation of abnormal (18)FDG foci in children with cancer, mainly by excluding the presence of active malignancy in sites of increased tracer activity.
Bar-Sever
Zvi
Z
Division of Nuclear Medicine, Schneider Children's Medical Center of Israel, 14 Kaplan Street, Petach-Tikva, 49202, Israel. barsever@clalit.org.il.|Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel. barsever@clalit.org.il.
Keidar
Zohar
Z
Department of Nuclear Medicine, Rambam Medical Center, Haifa, Israel.|B. Rapaport School of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
Ben-Barak
Ayelet
A
Department of Paediatric Oncology, Rambam Medical Center, Haifa, Israel.
Bar-Shalom
Rachel
R
Department of Nuclear Medicine, Rambam Medical Center, Haifa, Israel.
Postovsky
Sergey
S
Department of Paediatric Oncology, Rambam Medical Center, Haifa, Israel.
Guralnik
Luda
L
Department of Diagnostic Radiology, Rambam Medical Center, Haifa, Israel.
Ben Arush
Myriam W
MW
Department of Paediatric Oncology, Rambam Medical Center, Haifa, Israel.
Israel
Ora
O
Department of Nuclear Medicine, Rambam Medical Center, Haifa, Israel.|B. Rapaport School of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003952:Diagnostic Imaging / Q000379:methods; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008223:Lymphoma / Q000175:diagnosis / Q000000981:diagnostic imaging; D008297:Male; D009369:Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D014057:Tomography, X-Ray Computed / Q000379:methods*
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18