%0 Journal Article %A Ceccon, Garry %A Lohmann, Philipp %A Stoffels, Gabriele %A Judov, Natalie %A Filss, Christian %A Rapp, Marion %A Bauer, Elena %A Hamisch, Christina %A Ruge, Maximilian I. %A Kocher, Martin %A Kuchelmeister, Klaus %A Sellhaus, Bernd %A Sabel, Michael %A Fink, Gereon R. %A Shah, Nadim J. %A Langen, Karl-Josef %A Galldiks, Norbert %T Dynamic O -(2-$^{18}$ F-fluoroethyl)-L-tyrosine positron emission tomography differentiates brain metastasis recurrence from radiation injury after radiotherapy %J Neuro-Oncology %V 19 %N 2 %@ 1523-5866 %C Oxford %I Oxford Univ. Press %M FZJ-2017-00120 %P 281-288 %D 2017 %X BackgroundThe aim of this study was to investigate the potential of dynamic O-(2-[18F]fluoroethyl)-L-tyrosine (18F-FET) PET for differentiating local recurrent brain metastasis from radiation injury after radiotherapy since contrast-enhanced MRI often remains inconclusive.MethodsSixty-two patients (mean age, 55 ± 11 y) with single or multiple contrast-enhancing brain lesions (n = 76) on MRI after radiotherapy of brain metastases (predominantly stereotactic radiosurgery) were investigated with dynamic 18F-FET PET. Maximum and mean tumor-to-brain ratios (TBRmax, TBRmean) of 18F-FET uptake were determined (20–40 min postinjection) as well as tracer uptake kinetics (ie, time-to-peak and slope of time-activity curves). Diagnoses were confirmed histologically (34%; 26 lesions in 25 patients) or by clinical follow-up (66%; 50 lesions in 37 patients). Diagnostic accuracies of PET parameters for the correct identification of recurrent brain metastasis were evaluated by receiver-operating-characteristic analyses or the chi-square test.ResultsTBRs were significantly higher in recurrent metastases (n = 36) than in radiation injuries (n = 40) (TBRmax 3.3 ± 1.0 vs 2.2 ± 0.4, P < .001; TBRmean 2.2 ± 0.4 vs 1.7 ± 0.3, P < .001). The highest accuracy (88%) for diagnosing local recurrent metastasis could be obtained with TBRs in combination with the slope of time-activity curves (P < .001).ConclusionsThe results of this study confirm previous preliminary observations that the combined evaluation of the TBRs of 18F-FET uptake and the slope of time-activity curves can differentiate local brain metastasis recurrence from radiation-induced changes with high accuracy. 18F-FET PET may thus contribute significantly to the management of patients with brain metastases. %F PUB:(DE-HGF)16 %9 Journal Article %U <Go to ISI:>//WOS:000397280500015 %$ pmid:27471107 %R 10.1093/neuonc/now149 %U https://juser.fz-juelich.de/record/825818