title: (18)F-FDG PET in Pediatric Lymphomas: A Comparison with Conventional Imaging.
abstract: This study reports on our experience with 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in pediatric patients affected by Hodgkin's disease (HD) and non-Hodgkin's lymphoma (NHL). We studied 20 pediatric subjects (12 males, 8 females; mean age, 10 years; range, 6 months to 14 years) with malignant lymphoma (9 HD, 11 NHL) for a 4-year period of time. Overall, 45 PET scans were performed: 7 at disease presentation and 38 for evaluation of response to therapy or follow-up study. All PET results were compared with conventional imaging (CI), mainly computed tomography (CT) and/or magnetic resonance imaging (MRI), and supported by clinical follow-up and/or histologic data. In 18 of 20 patients, PET findings correctly identified the status of disease. Two (2) subjects (respectively, 1 HD and 1 NHL, both at follow-up) resulted falsely positive: 1 due to prominent thymic uptake, and the other due to nonspecific inflammation. Of 45 scans, PET findings were consistent with clinical follow-up and other CI data in 43 cases (16 true-positive and 27 true-negative results) and resulted falsely positive in the remaining 2 scans. On a lesion-by-lesion basis (overall, 153 lesions: 84 nodal and 69 extranodal), we found a concordance between CI and PET findings in 25 nodal (29.8%) and in 22 extranodal sites (32%). PET was more accurate than CI, as it identified active disease in 1 patient negative at CI and excluded relapse in 6 patients with inconclusive CI and in 2 patients with a falsely positive CI. Overall, PET sensitivity and specificity was 100% and 93% versus 94% sensitivity and 72.4% specificity for CI. This comparative study shows FDG PET to be more accurate than CI in evaluating children with lymphoma. Our data also confirms that (18)F-FDG PET may show false-positive findings.
authors.affiliation: Department of Nuclear Medicine, Policlinico "S. Orsola-Malpighi," Bologna, Italy.
authors.forename: Egesta
authors.initials: E
authors.lastname: Lopci
authors.forename: Roberta
authors.initials: R
authors.lastname: Burnelli
authors.forename: Valentina
authors.initials: V
authors.lastname: Ambrosini
authors.forename: Cristina
authors.initials: C
authors.lastname: Nanni
authors.forename: Paolo
authors.initials: P
authors.lastname: Castellucci
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Biassoni
authors.forename: Domenico
authors.initials: D
authors.lastname: Rubello
authors.forename: Stefano
authors.initials: S
authors.lastname: Fanti
mesh_terms: D000293:Adolescent; D002648:Child; D005260:Female; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D006689:Hodgkin Disease / Q000000981:diagnostic imaging*; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000000981:diagnostic imaging*; D008279:Magnetic Resonance Imaging; D008297:Male; D009367:Neoplasm Staging; D017063:Outcome Assessment, Health Care; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18