PT - JOURNAL ARTICLE AU - Veronika Dunkl AU - Corvin Cleff AU - Gabriele Stoffels AU - Natalie Judov AU - Sevgi Sarikaya-Seiwert AU - Ian Law AU - Lars Bøgeskov AU - Karsten Nysom AU - Sofie B. Andersen AU - Hans-Jakob Steiger AU - Gereon R. Fink AU - Guido Reifenberger AU - Nadim J. Shah AU - Heinz H. Coenen AU - Karl-Josef Langen AU - Norbert Galldiks TI - The Usefulness of Dynamic <em>O</em>-(2-<sup>18</sup>F-Fluoroethyl)-<span class="sc">l</span>-Tyrosine PET in the Clinical Evaluation of Brain Tumors in Children and Adolescents AID - 10.2967/jnumed.114.148734 DP - 2015 Jan 01 TA - Journal of Nuclear Medicine PG - 88--92 VI - 56 IP - 1 4099 - http://jnm.snmjournals.org/content/56/1/88.short 4100 - http://jnm.snmjournals.org/content/56/1/88.full SO - J Nucl Med2015 Jan 01; 56 AB - Experience regarding O-(2-18F-fluoroethyl)-l-tyrosine (18F-FET) PET in children and adolescents with brain tumors is limited. Methods: Sixty-nine 18F-FET PET scans of 48 children and adolescents (median age, 13 y; range, 1–18 y) were analyzed retrospectively. Twenty-six scans to assess newly diagnosed cerebral lesions, 24 scans for diagnosing tumor progression or recurrence, 8 scans for monitoring of chemotherapy effects, and 11 scans for the detection of residual tumor after resection were obtained. Maximum and mean tumor-to-brain ratios (TBRs) were determined at 20–40 min after injection, and time–activity curves of 18F-FET uptake were assigned to 3 different patterns: constant increase; peak at greater than 20–40 min after injection, followed by a plateau; and early peak (≤20 min), followed by a constant descent. The diagnostic accuracy of 18F-FET PET was assessed by receiver-operating-characteristic curve analyses using histology or clinical course as a reference. Results: In patients with newly diagnosed cerebral lesions, the highest accuracy (77%) to detect neoplastic tissue (19/26 patients) was obtained when the maximum TBR was 1.7 or greater (area under the curve, 0.80 ± 0.09; sensitivity, 79%; specificity, 71%; positive predictive value, 88%; P = 0.02). For diagnosing tumor progression or recurrence, the highest accuracy (82%) was obtained when curve patterns 2 or 3 were present (area under the curve, 0.80 ± 0.11; sensitivity, 75%; specificity, 90%; positive predictive value, 90%; P = 0.02). During chemotherapy, a decrease of TBRs was associated with a stable clinical course, and in 2 patients PET detected residual tumor after presumably complete tumor resection. Conclusion: Our findings suggest that 18F-FET PET can add valuable information for clinical decision making in pediatric brain tumor patients.