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Differentiation of pseudoprogression and real progression in glioblastoma using ADC parametric response maps

View Article: PubMed Central - PubMed

ABSTRACT

Purpose: The purpose of this study was to investigate whether a voxel-wise analysis of apparent diffusion coefficient (ADC) values may differentiate between progressive disease (PD) and pseudoprogression (PsP) in patients with high-grade glioma using the parametric response map, a newly introduced postprocessing tool.

Methods: Twenty-eight patients with proven PD and seven patients with PsP were identified in this retrospective feasibility study. For all patients ADC baseline and follow-up maps on four subsequent MRIs were available. ADC maps were coregistered on contrast enhanced T1-weighted follow-up images. Subsequently, enhancement in the follow-up contrast enhanced T1-weighted image was manually delineated and a reference region of interest (ROI) was drawn in the contralateral white matter. Both ROIs were transferred to the ADC images. Relative ADC (rADC) (baseline)/reference ROI values and rADC (follow up)/reference ROI values were calculated for each voxel within the ROI. The corresponding voxels of rADC (follow up) and rADC (baseline) were subtracted and the percentage of all voxels within the ROI that exceeded the threshold of 0.25 was quantified.

Results: rADC voxels showed a decrease of 59.2% (1st quartile (Q1) 36.7; 3rd quartile (Q3) 78.6) above 0.25 in patients with PD and 18.6% (Q1 3.04; Q3 26.5) in patients with PsP (p = 0.005). Receiver operating characteristic curve analysis showed the optimal decreasing rADC cut-off value for identifying PD of > 27.05% (area under the curve 0.844±0.065, sensitivity 0.86, specificity 0.86, p = 0.014).

Conclusion: This feasibility study shows that the assessment of rADC using parametric response maps might be a promising approach to contribute to the differentiation between PD and PsP. Further research in larger patient cohorts is necessary to finally determine its clinical utility.

No MeSH data available.


Related in: MedlinePlus

Analysis of a 38-year-old female patient with pseudoprogression (PsP).Contrast enhanced T1w MR images (A-B). Follow-up image with delineated tumor region of interest (ROI) (A). Parametric response map of relative apparent diffusion coefficient (rADC) (B). The resulting quantitave scatter plot (C). The voxels are color-coded corresponding to their changes between baseline and follow-up examinations. Blue is designated to voxels with a decrease of rADC ≥ 0.25, red to an increase of rACD < 0.25 and green to changes in between these thresholds.
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pone.0174620.g003: Analysis of a 38-year-old female patient with pseudoprogression (PsP).Contrast enhanced T1w MR images (A-B). Follow-up image with delineated tumor region of interest (ROI) (A). Parametric response map of relative apparent diffusion coefficient (rADC) (B). The resulting quantitave scatter plot (C). The voxels are color-coded corresponding to their changes between baseline and follow-up examinations. Blue is designated to voxels with a decrease of rADC ≥ 0.25, red to an increase of rACD < 0.25 and green to changes in between these thresholds.

Mentions: The calculation of the maximum Youden index (Youden index = 0.72, sensitivity = 0.86, specificity = 0.86) revealed a percentage of voxels with a decrease of rADC of 27.05% as an optimal cutoff value between PsP and PD. Thus, if the amount of these voxels exceeds 27.05%, the patient is likely to suffer from PD. Figs 2 and 3 show the analysis of a patient with PD and a patient with PsP respectively.


Differentiation of pseudoprogression and real progression in glioblastoma using ADC parametric response maps
Analysis of a 38-year-old female patient with pseudoprogression (PsP).Contrast enhanced T1w MR images (A-B). Follow-up image with delineated tumor region of interest (ROI) (A). Parametric response map of relative apparent diffusion coefficient (rADC) (B). The resulting quantitave scatter plot (C). The voxels are color-coded corresponding to their changes between baseline and follow-up examinations. Blue is designated to voxels with a decrease of rADC ≥ 0.25, red to an increase of rACD < 0.25 and green to changes in between these thresholds.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5383222&req=5

pone.0174620.g003: Analysis of a 38-year-old female patient with pseudoprogression (PsP).Contrast enhanced T1w MR images (A-B). Follow-up image with delineated tumor region of interest (ROI) (A). Parametric response map of relative apparent diffusion coefficient (rADC) (B). The resulting quantitave scatter plot (C). The voxels are color-coded corresponding to their changes between baseline and follow-up examinations. Blue is designated to voxels with a decrease of rADC ≥ 0.25, red to an increase of rACD < 0.25 and green to changes in between these thresholds.
Mentions: The calculation of the maximum Youden index (Youden index = 0.72, sensitivity = 0.86, specificity = 0.86) revealed a percentage of voxels with a decrease of rADC of 27.05% as an optimal cutoff value between PsP and PD. Thus, if the amount of these voxels exceeds 27.05%, the patient is likely to suffer from PD. Figs 2 and 3 show the analysis of a patient with PD and a patient with PsP respectively.

View Article: PubMed Central - PubMed

ABSTRACT

Purpose: The purpose of this study was to investigate whether a voxel-wise analysis of apparent diffusion coefficient (ADC) values may differentiate between progressive disease (PD) and pseudoprogression (PsP) in patients with high-grade glioma using the parametric response map, a newly introduced postprocessing tool.

Methods: Twenty-eight patients with proven PD and seven patients with PsP were identified in this retrospective feasibility study. For all patients ADC baseline and follow-up maps on four subsequent MRIs were available. ADC maps were coregistered on contrast enhanced T1-weighted follow-up images. Subsequently, enhancement in the follow-up contrast enhanced T1-weighted image was manually delineated and a reference region of interest (ROI) was drawn in the contralateral white matter. Both ROIs were transferred to the ADC images. Relative ADC (rADC) (baseline)/reference ROI values and rADC (follow up)/reference ROI values were calculated for each voxel within the ROI. The corresponding voxels of rADC (follow up) and rADC (baseline) were subtracted and the percentage of all voxels within the ROI that exceeded the threshold of 0.25 was quantified.

Results: rADC voxels showed a decrease of 59.2% (1st quartile (Q1) 36.7; 3rd quartile (Q3) 78.6) above 0.25 in patients with PD and 18.6% (Q1 3.04; Q3 26.5) in patients with PsP (p = 0.005). Receiver operating characteristic curve analysis showed the optimal decreasing rADC cut-off value for identifying PD of &gt; 27.05% (area under the curve 0.844&plusmn;0.065, sensitivity 0.86, specificity 0.86, p = 0.014).

Conclusion: This feasibility study shows that the assessment of rADC using parametric response maps might be a promising approach to contribute to the differentiation between PD and PsP. Further research in larger patient cohorts is necessary to finally determine its clinical utility.

No MeSH data available.


Related in: MedlinePlus