Pre- and Posttreatment Glioma: Comparison of Amide Proton Transfer Imaging with MR Spectroscopy for Biomarkers of Tumor Proliferation.
OBJECTIVE
To correlate and compare diagnostic performance with amide proton transfer (APT) imaging as a tumor proliferation index with that with magnetic resonance (MR) spectroscopy in subgroups of patients with pre- and posttreatment glioma.


METHODS
This retrospective study was approved by the institutional review board. In 40 patients with pretreatment glioma and 25 patients with posttreatment glioma, correlation between APT asymmetry and the choline-to-creatine and choline-to-N-acetylaspartate ratios in corresponding voxels of interest was determined, and the 90% histogram cutoff of APT asymmetry values (APT90) for the entire solid portion of gliomas was calculated for diagnostic performance. Area under the receiver operating characteristic curve (AUC), leave-one-out cross validation, and intraclass correlation coefficients were analyzed.


RESULTS
The APT asymmetry values showed a moderate correlation (r = 0.49, P < .001) with the choline-to-creatine ratios and a mild correlation with the choline-to-N-acetyl-aspartate ratios (r = 0.32, P = .011) in the corresponding lesions. The APT90 showed comparable diagnostic accuracy for grading of gliomas (AUC, 0.81-0.84 vs 0.86; P = .582-.864) and superior accuracy for differentiation of tumor progression from treatment-related change (AUC, 0.89-0.90 vs 0.60; P = .031-.046) compared with those with MR spectroscopy. The cross-validated area under the curve and accuracy of the APT90 in posttreatment gliomas were 0.89-0.90 and 72%, respectively. The interreader agreement for APT90 was excellent in both pretreatment and posttreatment gliomas (intraclass correlation coefficient, 0.95 and 0.96, respectively).


CONCLUSIONS
APT imaging used as a tumor proliferation index showed moderate correlation with MR spectroscopic values and is a superior imaging method to MR spectroscopy, particularly for assessment of posttreatment gliomas.
From the Department of Radiology and Research Institute of Radiology (J.E.P., H.S.K., K.J.P., S.J.K.) and Department of Neurosurgery (J.H.K.), University of Ulsan College of Medicine, Asan Medical Center, 86 Asanbyeongwon-Gil, Songpa-Gu, Seoul 138-736, Korea; and Department of Radiology and Radiological Sciences, Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tenn (S.A.S.).
Ji Eun
JE
Park
From the Department of Radiology and Research Institute of Radiology (J.E.P., H.S.K., K.J.P., S.J.K.) and Department of Neurosurgery (J.H.K.), University of Ulsan College of Medicine, Asan Medical Center, 86 Asanbyeongwon-Gil, Songpa-Gu, Seoul 138-736, Korea; and Department of Radiology and Radiological Sciences, Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tenn (S.A.S.).
Ho Sung
HS
Kim
From the Department of Radiology and Research Institute of Radiology (J.E.P., H.S.K., K.J.P., S.J.K.) and Department of Neurosurgery (J.H.K.), University of Ulsan College of Medicine, Asan Medical Center, 86 Asanbyeongwon-Gil, Songpa-Gu, Seoul 138-736, Korea; and Department of Radiology and Radiological Sciences, Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tenn (S.A.S.).
Kye Jin
KJ
Park
From the Department of Radiology and Research Institute of Radiology (J.E.P., H.S.K., K.J.P., S.J.K.) and Department of Neurosurgery (J.H.K.), University of Ulsan College of Medicine, Asan Medical Center, 86 Asanbyeongwon-Gil, Songpa-Gu, Seoul 138-736, Korea; and Department of Radiology and Radiological Sciences, Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tenn (S.A.S.).
Sang Joon
SJ
Kim
From the Department of Radiology and Research Institute of Radiology (J.E.P., H.S.K., K.J.P., S.J.K.) and Department of Neurosurgery (J.H.K.), University of Ulsan College of Medicine, Asan Medical Center, 86 Asanbyeongwon-Gil, Songpa-Gu, Seoul 138-736, Korea; and Department of Radiology and Radiological Sciences, Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tenn (S.A.S.).
Jeong Hoon
JH
Kim
From the Department of Radiology and Research Institute of Radiology (J.E.P., H.S.K., K.J.P., S.J.K.) and Department of Neurosurgery (J.H.K.), University of Ulsan College of Medicine, Asan Medical Center, 86 Asanbyeongwon-Gil, Songpa-Gu, Seoul 138-736, Korea; and Department of Radiology and Radiological Sciences, Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tenn (S.A.S.).
Seth A
SA
Smith
D000328:Adult; D000577:Amides; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001932:Brain Neoplasms / Q000378:metabolism* / Q000473:pathology* / Q000628:therapy; D018450:Disease Progression; D005260:Female; D005910:Glioma / Q000378:metabolism* / Q000473:pathology* / Q000628:therapy; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D011522:Protons; D016896:Treatment Outcome
D000577:Amides; D014408:Biomarkers, Tumor; D011522:Protons