Applying XXXX proton transfer-weighted @entity7994 to distinguish pseudoprogression from true progression in @entity11 .

@entity1 @entity7994 @entity5 @entity75 @entity11 @entity6346
PURPOSE: To assess @entity6346 proton transfer-weighted (APTW) imaging features in @entity1 with @entity11 after chemoradiation and the diagnostic performance of APT imaging for distinguishing true progression from pseudoprogression. MATERIALS AND METHODS: After approval by the Institutional Review Board, 32 @entity1 with clinically suspected @entity5 progression in the first 3 months after chemoradiation were enrolled and scanned at 3T. Longitudinal routine magnetic resonance imaging ( @entity7994 ) changes and medical records were assessed to confirm true progression versus pseudoprogression. True progression was @entity75 progressing on serial imaging over 6 months, and pseudoprogression was @entity75 stabilizing or regressing without intervention. The APTWmean and APTWmax signals were obtained from three to five regions of interests for each @entity1 and compared between the true progression and pseudoprogression groups. The diagnostic performance was assessed with receiver operating characteristic curve analysis. RESULTS: The true progression was associated with APTW hyperintensity (APTWmean    =   2.75%        0.42%), while pseudoprogression was associated with APTW isointensity to mild hyperintensity (APTWmean    =   1.56%        0.42%). The APTW signal intensities were significantly higher in the true progression group (n   =   20) than in the pseudoprogression group (P < 0.001; n   =   12). The cutoff APTWmean and APTWmax intensity values to distinguish between true progression and pseudoprogression were 2.42% (with a sensitivity of 85.0% and a specificity of 100%) and 2.54% (with a sensitivity of 95.0% and a specificity of 91.7%), respectively. CONCLUSION: The @entity7994 signal is a valuable imaging biomarker for distinguishing pseudoprogression from true progression in @entity11 @entity1 . J. Magn. Reson. Imaging 2016.
