UNLABELLED: PET using O-(2-[(18)F]fluoroethyl)-L-tyrosine ((18)F-FET) allows improved imaging of tumor extent of cerebral gliomas in comparison to MRI. In experimental brain infarction and hematoma, an unspecific accumulation of (18)F-FET has been detected in the area of reactive astrogliosis which is a common cellular reaction in the vicinity of cerebral gliomas. The aim of this study was to investigate possible (18)F-FET uptake in the area of reactive gliosis in the vicinity of untreated and irradiated rat gliomas. METHODS: F98-glioma cells were implanted into the caudate nucleus of 33 Fisher CDF rats. Sixteen animals remained untreated and in 17 animals the tumor was irradiated by Gamma Knife 5-8 days after implantation (2/50 Gy, 3/75 Gy, 6/100 Gy, 6/150 Gy). After 8-17 days of tumor growth the animals were sacrificed following injection of (18)F-FET. Brains were removed, cut in coronal sections and autoradiograms of (18)F-FET distribution were produced and compared with histology (toluidine blue) and reactive astrogliosis (GFAP staining). (18)F-FET uptake in the tumors and in areas of reactive astrocytosis was evaluated by lesion to brain ratios (L/B). RESULTS: Large F98-gliomas were present in all animals showing increased (18)F-FET-uptake which was similar in irradiated and non-irradiated tumors (L/B: 3.9 ± 0.8 vs. 4.0 ± 1.3). A pronounced reactive astrogliosis was noted in the vicinity of all tumors that showed significantly lower (18)F-FET-uptake than the tumors (L/B: 1.5 ± 0.4 vs. 3.9 ± 1.1). The area of (18)F-FET-uptake in the tumor was congruent with histological tumor extent in 31/33 animals. In 2 rats irradiated with 150 Gy, however, high (18)F-FET uptake was noted in the area of astrogliosis which led to an overestimation of the tumor size. CONCLUSIONS: Reactive astrogliosis in the vicinity of gliomas generally leads to only a slight (18)F-FET-enrichment that appears not to affect the correct definition of tumor extent for treatment planning.
UNLABELLED: PET using O-(2-[(18)F]fluoroethyl)-L-tyrosine ((18)F-FET) allows improved imaging of tumor extent of cerebral gliomas in comparison to MRI. In experimental brain infarction and hematoma, an unspecific accumulation of (18)F-FET has been detected in the area of reactive astrogliosis which is a common cellular reaction in the vicinity of cerebral gliomas. The aim of this study was to investigate possible (18)F-FET uptake in the area of reactive gliosis in the vicinity of untreated and irradiated ratgliomas. METHODS:F98-glioma cells were implanted into the caudate nucleus of 33 Fisher CDF rats. Sixteen animals remained untreated and in 17 animals the tumor was irradiated by Gamma Knife 5-8 days after implantation (2/50 Gy, 3/75 Gy, 6/100 Gy, 6/150 Gy). After 8-17 days of tumor growth the animals were sacrificed following injection of (18)F-FET. Brains were removed, cut in coronal sections and autoradiograms of (18)F-FET distribution were produced and compared with histology (toluidine blue) and reactive astrogliosis (GFAP staining). (18)F-FET uptake in the tumors and in areas of reactive astrocytosis was evaluated by lesion to brain ratios (L/B). RESULTS: Large F98-gliomas were present in all animals showing increased (18)F-FET-uptake which was similar in irradiated and non-irradiated tumors (L/B: 3.9 ± 0.8 vs. 4.0 ± 1.3). A pronounced reactive astrogliosis was noted in the vicinity of all tumors that showed significantly lower (18)F-FET-uptake than the tumors (L/B: 1.5 ± 0.4 vs. 3.9 ± 1.1). The area of (18)F-FET-uptake in the tumor was congruent with histological tumor extent in 31/33 animals. In 2 rats irradiated with 150 Gy, however, high (18)F-FET uptake was noted in the area of astrogliosis which led to an overestimation of the tumor size. CONCLUSIONS: Reactive astrogliosis in the vicinity of gliomas generally leads to only a slight (18)F-FET-enrichment that appears not to affect the correct definition of tumor extent for treatment planning.
Authors: Tineke van de Weijer; Martijn P G Broen; Rik P M Moonen; Ann Hoeben; Monique Anten; Koos Hovinga; Inge Compter; Jochem A J van der Pol; Cristina Mitea; Toine M Lodewick; Arnaud Jacquerie; Felix M Mottaghy; Joachim E Wildberger; Alida A Postma Journal: Diagnostics (Basel) Date: 2022-05-11
Authors: Carina Stegmayr; Ulrike Bandelow; Dennis Oliveira; Philipp Lohmann; Antje Willuweit; Christian Filss; Norbert Galldiks; Joachim H R Lübke; N Jon Shah; Johannes Ermert; Karl-Josef Langen Journal: Eur J Nucl Med Mol Imaging Date: 2016-09-09 Impact factor: 9.236
Authors: Carina Stegmayr; Michael Schöneck; Dennis Oliveira; Antje Willuweit; Christian Filss; Norbert Galldiks; N Jon Shah; Heinz H Coenen; Karl-Josef Langen Journal: Eur J Nucl Med Mol Imaging Date: 2015-12-08 Impact factor: 9.236
Authors: Sidsel Højklint Poulsen; Thomas Urup; Kirsten Grunnet; Ib Jarle Christensen; Vibeke Andrée Larsen; Michael Lundemann Jensen; Per Munck Af Rosenschöld; Hans Skovgaard Poulsen; Ian Law Journal: Eur J Nucl Med Mol Imaging Date: 2016-08-23 Impact factor: 9.236