Usefulness of a Pharmacokinetic Model Based on Dynamic Contrast-enhanced MRI for the Detection and Localization of Prostate Cancer

ABSTRACT

PURPOSE: To investigate the usefulness of a pharmacokinetic model based on dynamic contrast-enhanced (DCE) MR imaging for the detection and localization of prostate cancer. MATERIALS AND METHODS: Forty-four patients that had undergone radical prostatectomy for prostate cancer and dynamic contrast enhanced (DCE) MR imaging (slice thickness, 4 mm; time resolution of each set, 5 seconds), were enrolled in the study. From the pharmacokinetic model, the time of arrival, and the parameters Ah, Kep, and Kel were extracted and were compared for cancerous tissue and non-cancerous tissue in the central gland and peripheral zone. The diagnostic performance of each parameter for differentiating cancerous tissue from non-cancerous tissue was evaluated using receiver-operating-characteristics analysis. RESULTS: The Kep and Kel values were significantly greater in cancerous tissue (0.13 sec(-1) +/- 0.14 and 1.59 x 10(-3) sec(-1) +/- 1.35 x 10(-3)) than in non-cancerous tissue from the central gland (0.03 sec(-1) +/- 0.02 and 0.26 x 10(-3) sec(-1) +/- 1.24 x 10(-3)) and peripheral zone (0.04 sec(-1) +/- 0.07 and 0.58 x 10(-3) sec(-1) +/- 1.98 x10(-3)) (p < 0.05). The area under the ROC curve for differentiating cancerous from non-cancerous tissue was 0.850 (95% CI, 0.778-0.876) for Kep and 0.814 (95% CI, 0.737-0.876) for Kel. CONCLUSION: Kep and Kel are useful perfusion parameters for the differentiation of prostate cancerous tissue from non-cancerous tissue.