Treatment response monitoring in patients with gastrointestinal stromal tumor using diffusion‐weighted imaging: preliminary results in comparison with positron emission tomography/computed tomography. (16th July 2012)

• Record Type: Journal Article
• Authors: Gong, Nan‐Jie; Wong, Chun‐Sing; Chu, Yiu‐Ching; Gu, Jing
• Is Part Of: NMR in biomedicine. Volume 26:Number 2(2013:Feb.)
• Page Start: 185
• Page End: 192
• Publication Date: 2012-07-16
• Subjects: gastrointestinal stromal tumor (GIST) -- MRI -- positron emission tomography/computed tomography (PET/CT) -- diffusion‐weighted imaging (DWI) -- standardized uptake value (SUV) -- apparent diffusion coefficient (ADC) -- therapeutic monitoring; Nuclear magnetic resonance -- Periodicals; Magnetic Resonance Spectroscopy -- Periodicals; 574
• DOI: 10.1002/nbm.2834
• Languages: English
• ISSNs: 0952-3480

Abstract

Abstract : We compared the parameters derived from diffusion‐weighted imaging (DWI) and positron emission tomography/computed tomography (PET/CT) for treatment response evaluation and response prediction in patients with gastrointestinal stromal tumor (GIST). Seven patients with histologically proven metastatic disease were enrolled. DWI and PET/CT data were collected from all patients at diagnosis and from six at follow‐up. All 37 lesions were identifiable in DWI with a sensitivity of 100%. To achieve higher accuracy, we used the apparent diffusion coefficient (ADC) of liver and background noise as thresholds for the measurement of the ADCs of lesions. Significant inverse correlations were found between ADCmean_thr (ADCmean with thresholds) and SUVmean (mean standardized uptake value) ( R 2 = 0.523, p < 0.001 at diagnosis, and R 2 = 0.916, p < 0.001 at follow‐up), between ADCmean_thr and SUVmax (maximum SUV) ( R 2 = 0.529, p < 0.001 at diagnosis, and R 2 = 0.761, p < 0.001 at follow‐up), between ΔADCmean_thr (percentage change in ADCmean_thr ) and ΔSUVmean (percentage change in SUVmean ) ( R 2 = 0.384, p < 0.001), and between ΔADCmean_thr and ΔSUVmax (percentage change in SUVmax ) ( R 2 = 0.500, p < 0.001). In lesion‐based analysis, pre‐treatment ADCmean_thr outperformed SUVmean and SUVmax in treatment response prediction, with an area under the receiver operating characteristic curve of 0.706. These results show that DWI can provide a quantitative assessment comparable with PET/CT in GIST lesion characterization, treatment response evaluation and response prediction. Copyright © 2012 John Wiley & Sons, Ltd. Abstract : To achieve higher accuracy in the measurement of apparent diffusion coefficients (ADCs) of lesions, a more objective threshold ADC measurement approach, which uses liver and background noise ADCs as thresholds, was introduced. The absolute value of this parameter (ADCmean_thr ) at both initial and follow‐up imaging and its percentage change demonstrated significant correlations with those of SUVmean and SUVmax . These findings indicated that diffusion‐weighted imaging could provide quantitative assessment comparable with positron emission tomography/computed tomography in gastrointestinal stromal tumor characterization, treatment response evaluation and response prediction.