RT Journal Article
SR Electronic
T1 Flare Phenomenon in <em>O</em>-(2-<sup>18</sup>F-Fluoroethyl)-<span class="sc">l</span>-Tyrosine PET After Resection of Gliomas
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 1294
OP 1299
DO 10.2967/jnumed.119.238568
VO 61
IS 9
A1 Christian P. Filss
A1 Ann K. Schmitz
A1 Gabriele Stoffels
A1 Carina Stegmayr
A1 Philipp Lohmann
A1 Jan Michael Werner
A1 Michael Sabel
A1 Marion Rapp
A1 Roland Goldbrunner
A1 Bernd Neumaier
A1 Felix M. Mottaghy
A1 N. Jon Shah
A1 Gereon R. Fink
A1 Norbert Galldiks
A1 Karl-Josef Langen
YR 2020
UL http://jnm.snmjournals.org/content/61/9/1294.abstract
AB 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 in 18F-FET uptake at the rim of the resection cavity within the first 2 wk 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 d; range, 5–28 d) were included. PET scans (20–40 min after injection) were evaluated visually for complete or incomplete resection and compared with MRI. Changes in 18F-FET uptake were evaluated by tumor-to-brain ratios in residual tumor and by maximum lesion-to-brain ratios near the resection cavity. Results: Visual analysis of 18F-FET PET scans revealed complete resection in 16 of 43 patients and incomplete resection in the remaining patients. PET results were concordant with MRI in 69% of the patients. The maximum lesion-to-brain ratio for 18F-FET uptake near the resection cavity was significantly higher than preoperative values (1.59 ± 0.36 vs. 1.14 ± 0.17; n = 43; P &lt; 0.001). In 11 patients (26%), a flare phenomenon was observed, with a considerable increase in 18F-FET uptake compared with preoperative values in either the residual tumor (n = 5) or areas remote from the tumor on the preoperative PET scan (n = 6) (2.92 ± 1.24 vs. 1.62 ± 0.75; P &lt; 0.001). Further follow-up in 5 patients showed decreasing 18F-FET uptake in the flare areas in 4 patients and progress in 1 patient. Conclusion: Our study confirmed 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.