656 AJR:208, March 2017 gy database (Esh-IGT, Esh). Cases were identifed by cross-referencing all cases of image-guided bi- opsy in the interventional radiology database with all PET/CT reports in the PACS. At the time of this study, patients underwent PET/CT mainly for staging (Fig. 1) or follow-up of suspected recur- rent disease, not specifcally to guide the biopsy. Patients were referred for biopsy for a variety of reasons: primary histologic diagnosis of lesions identifed at imaging, if tissue diagnosis would substantially alter future management of known disease, if there was a disconnect between clini- cal and imaging fndings (e.g., liver function test results), to differentiate infectious from malignant lesions, or to determine the presence of residual disease. Patients who underwent image-guided biopsy before or after a PET/CT examination be- tween January 2007 and December 2012 were in- cluded in the analysis. The inclusion criterion was performance of image-guided biopsy within 6 weeks of PET/CT, either before or after the biopsy. The interval use of any treatment (chemotherapy, surgery, radiation) between biopsy and PET/CT was noted because it could confound the result. Patient demographic data (age, sex, weight, and underlying diagnosis if known) were collected. Data pertaining to PET/CT included patient age and weight at the examination, FDG dose, and presence or absence of pathologic uptake at the Correlation of PET/CT and Image-Guided Biopsies of Pediatric Malignancies Saeed Nihayah 1,2 Amer Shammas 3 Reza Vali 3 Dimitri Parra 2 Sarah Alexander 4 Joao Amaral 4 Bairbre Connolly 2 Nihayah S, Shammas A, Vali R, et al. 1 Department of Radiology, Prince Sultan Military Medical City, PO Box 7897, Riyadh 11159, Kingdom of Saudi Arabia. Address correspondence to S. Nihayah (snehaiah@psmmc.med.sa or drnihayah@hotmail.com). 2 Division of Image Guided Therapy, Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto, ON, Canada. 3 Division of Nuclear Medicine, Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto, ON, Canada. 4 Department of Hematology and Oncology, The Hospital for Sick Children, Toronto, ON, Canada. Vascular and Interventional Radiology • Original Research AJR 2017; 208:656–662 0361–803X/17/2083–656 © American Roentgen Ray Society P ET/CT with 18 F-FDG is increas- ingly used in the evaluation of on- cology patients [1–16]. PET/CT can be used in the diagnostic workup of children with suspected malig- nancy and for staging and follow-up after an oncologic diagnosis is established [1, 4, 8, 12]. Positive PET/CT fndings alone, howev- er, are not specifc for malignancy. Infam- mation, infection, and other benign condi- tions can also exhibit increased FDG uptake [1, 4, 8, 12]. Biopsy may be required for de- fnitive histopathologic diagnosis, which af- fects subsequent clinical management [1]. There is limited information in the English literature on the association between PET/CT fndings and the results of image-guided per - cutaneous biopsy in the pediatric population. The purpose of this study is to evaluate, through our early experience, the correlation between PET/CT and image-guided biopsy results in a pediatric population. Materials and Methods Research ethics board approval was obtained for this single-center retrospective study. The re- quirement for individual consent was waived. Data sources included the hospital electronic pa- tient chart, PACS, and the interventional radiolo- Keywords: children’s malignancies, image-guided biopsy, malignancies, PET/CT DOI:10.2214/AJR.15.15914 Received November 23, 2015; accepted after revision August 27, 2016. OBJECTIVE. The purpose of this study was to evaluate an early experience with correla- tion of PET/CT fndings and image-guided biopsy results in pediatric patients. MATERIALS AND METHODS. In a single-center retrospective case series, the inclu- sion criterion was performance of image-guided biopsy within 6 weeks of PET/CT, either be- fore or after the biopsy. RESULTS. Forty-fve patients (23 boys, 22 girls; age range, 4–17 years; median, 10.5 years; weight range, 14.6–86.2 kg; median, 48 kg) underwent 47 PET/CT examinations and biopsies. Nineteen patients (20 biopsies) had known malignancy, and 26 patients had suspect- ed malignancy. The results were malignant in 24 cases, benign in 16, and inadequate or nor- mal in 7 cases. Thirty-nine of 47 PET/CT examinations had positive results, and eight had negative results. Final analysis of 37 of the 47 cases (confounders excluded) showed concor - dant results between biopsy and PET in 36 cases and discordant results in one case. CONCLUSION. PET/CT can be used for disease staging and follow-up. In the future PET/CT can play a valuable role in directing image-guided biopsies of children. Nihayah et al. PET/CT of Pediatric Malignancies Vascular and Interventional Radiology Original Research Downloaded from www.ajronline.org by 52.73.204.196 on 05/13/22 from IP address 52.73.204.196. Copyright ARRS. For personal use only; all rights reserved