TY  - JOUR
AU  - Galldiks, N.
AU  - Langen, K.J.
AU  - Holy, R.
AU  - Pinkawa, M.
AU  - Stoffels, G.
AU  - Nolte, K.W.
AU  - Kaiser, H.J.
AU  - Filss, C.P.
AU  - Fink, G.R.
AU  - Coenen, H.H.
AU  - Eble, M.J.
AU  - Piroth, M.D.
TI  - Assessment of treatment response in patients with glioblastoma using [18F]Fluoroethyl-L-Tyrosine PET in comparison to MRI
JO  - Journal of nuclear medicine
VL  - 53
IS  - 7
SN  - 0161-5505
CY  - New York, NY
PB  - Society of Nuclear Medicine
M1  - PreJuSER-21886
SP  - 1048-1057
PY  - 2012
N1  - Record converted from VDB: 12.11.2012
AB  - The assessment of treatment response in glioblastoma is difficult with MRI because reactive blood-brain barrier alterations with contrast enhancement can mimic tumor progression. In this study, we investigated the predictive value of PET using O-(2-(18)F-fluoroethyl)-l-tyrosine ((18)F-FET PET) during treatment.In a prospective study, 25 patients with glioblastoma were investigated by MRI and (18)F-FET PET after surgery (MRI-/FET-1), early (7-10 d) after completion of radiochemotherapy with temozolomide (RCX) (MRI-/FET-2), and 6-8 wk later (MRI-/FET-3). Maximum and mean tumor-to-brain ratios (TBR(max) and TBR(mean), respectively) were determined by region-of-interest analyses. Furthermore, gadolinium contrast-enhancement volumes on MRI (Gd-volume) and tumor volumes in (18)F-FET PET images with a tumor-to-brain ratio greater than 1.6 (T(vol 1.6)) were calculated using threshold-based volume-of-interest analyses. The patients were grouped into responders and nonresponders according to the changes of these parameters at different cutoffs, and the influence on progression-free survival and overall survival was tested using univariate and multivariate survival analyses and by receiver-operating-characteristic analyses.Early after completion of RCX, a decrease of both TBR(max) and TBR(mean) was a highly significant and independent statistical predictor for progression-free survival and overall survival. Receiver-operating-characteristic analysis showed that a decrease of the TBR(max) between FET-1 and FET-2 of more than 20% predicted poor survival, with a sensitivity of 83% and a specificity of 67% (area under the curve, 0.75). Six to eight weeks later, the predictive value of TBR(max) and TBR(mean) was less significant, but an association between a decrease of T(vol 1.6) and PFS was noted. In contrast, Gd-volume changes had no significant predictive value for survival.In contrast to Gd-volumes on MRI, changes in (18)F-FET PET may be a valuable parameter to assess treatment response in glioblastoma and to predict survival time.
KW  - Adult
KW  - Aged
KW  - Brain Neoplasms: radionuclide imaging
KW  - Brain Neoplasms: therapy
KW  - Chemoradiotherapy
KW  - Contrast Media
KW  - Disease Progression
KW  - Disease-Free Survival
KW  - Female
KW  - Gadolinium
KW  - Glioblastoma: radionuclide imaging
KW  - Glioblastoma: therapy
KW  - Humans
KW  - Kaplan-Meier Estimate
KW  - Magnetic Resonance Imaging
KW  - Male
KW  - Middle Aged
KW  - Neurosurgical Procedures
KW  - Positron-Emission Tomography
KW  - Prognosis
KW  - Proportional Hazards Models
KW  - Prospective Studies
KW  - Radiopharmaceuticals: diagnostic use
KW  - Survival Analysis
KW  - Treatment Outcome
KW  - Tyrosine: analogs & derivatives
KW  - Tyrosine: diagnostic use
KW  - (18F)fluoroethyltyrosine (NLM Chemicals)
KW  - Contrast Media (NLM Chemicals)
KW  - Radiopharmaceuticals (NLM Chemicals)
KW  - Tyrosine (NLM Chemicals)
KW  - Gadolinium (NLM Chemicals)
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
C6  - pmid:22645298
UR  - <Go to ISI:>//WOS:000306164600020
DO  - DOI:10.2967/jnumed.111.098590
UR  - https://juser.fz-juelich.de/record/21886
ER  -