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

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 (t₀), and enhancement rate (α)), sigmoidal (amplitude (A₀), center time relative to arrival time (A₁ - T₀), and slope (A₂)), 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, A₁ - T₀, and A₂ 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.