The Impact of Arterial Input Function Determination Variations on Prostate Dynamic Contrast-Enhanced Magnetic Resonance Imaging Pharmacokinetic Modeling: A Multicenter Data Analysis Challenge.

"Conflict of Interest: None reported. Disclosure: No disclosures to report."

"This study was supported by National Institutes of Health grants U01-CA154602, U01-CA151261, U01-CA183848, U01-CA154601, U01-CA148131, U01-CA176110, U01-CA172320, U01-CA142565, U01-CA166104, and U01-CA140230. Other than OHSU (which was the managing center) and BWH (which provided the shared prostate DCE-MRI data), all other participating QIN centers contributed equally to this study. The results from this multicenter challenge project are supported by findings from a recent simulation study (unpublished results), which aims to identify pharmacokinetic parameters that are relatively insensitive to AIF variations. In fact, the simulations show complete kep insensitivity to AIF magnitude errors (unpublished results). The current study shows that for TM analysis, kep is less sensitive to AIF uncertainty when compared with Ktrans. Defined as the CR intravasation rate constant, kep is predominantly characterized by the washout phase of the DCE time-course. Because kep is often calculated as Ktrans/ve and not as an independent variable in model fitting of the DCE time-course data, it is sometimes underused in clinical DCE-MRI studies. Results from this work, however, suggest that, considering the uncertainties in AIF determination, kep may be a more reproducible DCE-MRI parameter than the Ktrans parameter and thus a more robust imaging biomarker of perfusion and permeability. For prostate DCE-MRI, kep can offer a different perspective of prostate microvasculature, particularly when the Ktrans ranges of benign and cancerous tissue overlap ()."