No abstract

3/125 and 0/30 features with CoV<0.05 respectively). Mean signal intensity ratio F1/SIM in GTV correlates strongly with corresponding changes in ROI_tis (Pearson r Z 0.88, p Z 0.0006), with no significant trend in either (t-test p Z 0.28 and p Z 0.46). Histogram width features in tumor show an increase SIM-F1 and a drop F1-F5 (e.g. Interquartile range (IQR): p Z 0.042, 1.3AE0.4 vs. 0.92AE0.19 F1/SIM vs. F5/F1 ratios, Standard Deviation (SD): p Z 0.08, 1.3AE0.5 vs. 0.93AE0.15). The only patient with pathological complete response at surgery was also only one of 10 to show SIM-F1 decrease (ratios: IQR 0.96, SD 0.92). Normalization by median ROI_tis signal further strengthened the trend (IQR p Z 0.01, SD p Z 0.005). No trends were seen in ROI_tis (IQR p Z 0.50, SD p Z 0.48). Conclusion: These results present early application for the radiomic and histogram analysis for MRgRT image quantification. PDAC may be difficult to define in TRUFI MRgRT images, highlighting the value of observed high spatial robustness of features. Tumor specific changes in histogram width were observed. These metrics, associated with tumor internal heterogeneity, show promise to elucidate clinically relevant information from the images. Preliminary link with histological response was established. Efficient normalization method was found to improve sensitivity. More work is required to understand the biological basis of the observed trends.