Comparison of Early Contrast Enhancement Models in Ultrafast Dynamic Contrast-Enhanced Magnetic Resonance Imaging of Prostate Cancer.

Tofts models have failed to produce reliable quantitative markers for prostate cancer. We examined the differences between prostate zones and lesion PI-RADS categories and grade group (GG) using regions of interest drawn in tumor and normal-appearing tissue for a two-compartment uptake (2CU) model (including plasma volume (v p ), plasma flow (F p ), permeability surface area product (PS), plasma mean transit time (MTT p ), capillary transit time (T c ), extraction fraction (E), and transfer constant (K trans )) and exponential (amplitude (A), arrival time (t 0 ), and enhancement rate (α)), sigmoidal (amplitude (A 0 ), center time relative to arrival time (A 1 - T 0 ), and slope (A 2 )), and empirical mathematical models, and time to peak (TTP) parameters fitted to high temporal resolution (1.695 s) DCE-MRI data. In 25 patients with 35 PI-RADS category 3 or higher tumors, we found F p and α differed between peripheral and transition zones. Parameters F p , MTT p , T c , E, α, A 1 - T 0 , and A 2 and TTP all showed associations with PI-RADS categories and with GG in the PZ when normal-appearing regions were included in the non-cancer GG. PS and K trans were not associated with any PI-RADS category or GG. This pilot study suggests early enhancement parameters derived from ultrafast DCE-MRI may become markers of prostate cancer.