Inter-Vendor Variability of Perfusion Parameters Derived from Dynamic Contrast-Enhanced MRI in Patients with Prostate...

Purpose: To investigate the agreement on perfusion parameters derived from two different commercially available solutions for dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in patients with prostate cancer (PCa). Methods: A total of 50 patients (mean age, 71.6; range 56-86) who had undergone radical prostatectomy between December 2021 and September 2022 were included in this retrospective study. All patients had undergone DCE-MRI on a single 3T-MR scanner. Tumor segmentation on MR images was performed by two radiologists in consensus after radiologic-pathologic correlation using topographic maps as a reference standard. Subsequently, four perfusion parameters were calculated by dedicated commercially available solutions from two different vendors. Both solutions adopted a population-based arterial input function and an extended Tofts model as the pharmacokinetic model. The perfusion parameters were as follows; volume transfer constant (K^trans), rate constant (k_ep), volume fraction of extravascular extracellular space (v_e), and volume fraction of plasma (v_p). The differences between paired measurements were compared by Bland-Altman analyses and the reproducibility was evaluated using the intraclass correlation coefficient (ICC). Results: The study population consisted of Gleason score (GS) 6 (n = 12), GS 7 (n = 34), GS 8 (n = 1), and GS 9 (n = 3). Significant differences were found for all parameters (p < 0.0001). Mean differences were as follows: K^trans, -0.2102 (95% confidence interval; -0.2687 to -0.1518); k_ep, -0.7632 (-0.9005 to -0.6258); v_e, -0.1507 (-0.2422 to -0.05907); v_p, -0.02929 (-0.03383 to -0.02476). ICCs for average measures were as follows: K^trans, 0.2989 (-0.2355 to 0.6021); k_ep, 0.6883 (0.4507 to 0.8231); v_e, -0.1331 (-0.9967 to 0.3570); v_p, 0.2653 (-0.3106 to 0.5881). Conclusion: All perfusion parameters were significantly different between the two solutions. Therefore, comparison of perfusion parameters across different solutions is not recommended.