TY  - JOUR
AU  - Galldiks, Norbert
AU  - Unterrainer, Marcus
AU  - Judov, Natalie
AU  - Stoffels, Gabriele
AU  - Rapp, Marion
AU  - Lohmann, Philipp
AU  - Vettermann, Franziska
AU  - Dunkl, Veronika
AU  - Suchorska, Bogdana
AU  - Tonn, Jörg C
AU  - Kreth, Friedrich-Wilhem
AU  - Fink, Gereon Rudolf
AU  - Bartenstein, Peter
AU  - Langen, Karl-Josef
AU  - Albert, Nathalie L
TI  - Photopenic defects on O-(2-[18F]-fluoroethyl)-L-tyrosine PET - Clinical relevance in glioma patients
JO  - Neuro-Oncology
VL  - 21
IS  - 10
SN  - 1523-5866
CY  - Oxford
PB  - Oxford Univ. Press
M1  - FZJ-2019-02976
SP  - 1331-1338
PY  - 2019
AB  - BackgroundO-(2-[18F]-fluoroethyl)-L-tyrosine (FET) PET has a sensitivity of more than 90% to detect gliomas. In the remaining small fraction of gliomas without increased tracer uptake, some tumors even show photopenic defects whose clinical significance is unclear.MethodsGlioma patients with a negative FET PET scan prior to neuropathological confirmation were identified retrospectively. Gliomas were rated visually as (i) having indifferent FET uptake or (ii) photopenic, if FET uptake was below background activity. FET uptake in the area of signal hyperintensity on the T2/fluid attenuated inversion recovery–weighted MRI was evaluated by mean standardized uptake value (SUV) and mean tumor-to-brain ratio (TBR). The progression-free survival (PFS) of photopenic gliomas was compared with that of gliomas with indifferent FET uptake.ResultsOf 100 FET-negative gliomas, 40 cases with photopenic defects were identified. Fifteen of these 40 cases (38%) had World Health Organization (WHO) grades III and IV gliomas. FET uptake in photopenic gliomas was significantly decreased compared with both the healthy-appearing brain tissue (SUV, 0.89 ± 0.26 vs 1.08 ± 0.23; P < 0.001) and gliomas with indifferent FET uptake (TBR, 0.82 ± 0.09 vs 0.96 ± 0.13; P < 0.001). Irrespective of the applied treatment, isocitrate dehydrogenase (IDH)–mutated WHO grade II diffuse astrocytoma patients with indifferent FET uptake (n = 25) had a significantly longer PFS than patients with IDH-mutated diffuse astrocytomas (WHO grade II) with photopenic defects (n = 11) (51 vs 24 mo; P = 0.027). The multivariate survival analysis indicated that photopenic defects predict an unfavorable PFS (P = 0.009).ConclusionPhotopenic gliomas in negative FET PET scans should be managed more actively, as they seem to have a higher risk of harboring a higher-grade glioma and an unfavorable outcome.
LB  - PUB:(DE-HGF)16
C6  - pmid:31077276
UR  - <Go to ISI:>//WOS:000493086800015
DO  - DOI:10.1093/neuonc/noz083
UR  - https://juser.fz-juelich.de/record/862734
ER  -