%0 Journal Article
%A Filss, Christian P
%A Schmitz, Ann k
%A Stoffels, Gabriele
%A Stegmayr, Carina
%A Lohmann, Philipp
%A Werner, Jan Michael
%A Sabel, Michael
%A Rapp, Marion
%A Goldbrunner, Roland
%A Neumaier, Bernd
%A Mottaghy, Felix M.
%A Shah, N. Jon
%A Fink, Gereon R
%A Galldiks, Norbert
%A Langen, Karl Josef
%T Flare phenomenon in O-(2-[ 18 F]-Fluoroethyl)-L-Tyrosine PET after resection of gliomas
%J Journal of nuclear medicine
%V 61
%N 9
%@ 0022-3123
%C New York, NY
%I Soc.
%M FZJ-2020-00214
%P  1294-1299 
%D 2020
%X PET using O-(2-[18F]Fluoroethyl)-L-tyrosine (18F-FET) is useful to detect residual tumor tissue after glioma resection. Recent animal experiments detected reactive changes of 18F-FET uptake at the rim of the resection cavity within the first two weeks after resection of gliomas. In the present study, we evaluated pre- and postoperative 18F-FET PET scans of glioma patients with particular emphasis on the identification of reactive changes after surgery. Methods: Forty-three patients with cerebral gliomas (9 low-grade, 34 high-grade; 9 primary tumors, 34 recurrent tumors) who had preoperative (time before surgery, median 23 d, range 6-44 d) and postoperative 18F-FET-PET (time after surgery, median 14, range 5–28 d) were included. PET scans (20-40 min p.i.) were evaluated visually for complete or incomplete resection (CR, IR) and compared with MRI. Changes of 18F-FET-uptake in residual tumor were evaluated by tumor-to-brain ratios (TBRmax) and in the vicinity of the resection cavity by maximum lesion-to-brain ratios (LBRmax). Results: Visual analysis of 18F-FET PET scans revealed CR in 16/43 patients and IR in the remaining patients. PET results were concordant with MRI in 69% of the patients. LBRmax of 18F-FET uptake in the vicinity of the resection cavity was significantly higher compared with preoperative values (1.59 ± 0.36 versus 1.14 ± 0.17; n = 43, p<0.001). In 11 patients (26%) a “flare phenomenon” was observed with a considerable increase of 18F-FET uptake compared with preoperative values in either the residual tumor (n = 5) or in areas remote from tumor in the preoperative PET scan (n = 6) (2.92 ± 1.24 versus 1.62 ± 0.75; p<0.001). Further follow-up in five patients showed decreasing 18F-FET uptake in the flare areas in four and progress in one case. Conclusion: Our study confirms that 18F-FET PET provides valuable information for assessing the success of glioma resection. Postoperative reactive changes at the rim of the resection cavity appear to be mild. However, in 23 % of the patients, a postoperative “flare phenomenon” was observed that warrants further investigation.
%F PUB:(DE-HGF)16
%9 Journal Article
%$ pmid:32005771
%U <Go to ISI:>//WOS:000568832100013
%R 10.2967/jnumed.119.238568
%U https://juser.fz-juelich.de/record/872736