Studying Repeated DCE-MRI and DWI in Patients Diagnosed With Prostate Cancer

OBJECTIVES: Primary * Determine the test-retest performance, assessed by the repeatability coefficient \[RC\] of K\^trans and gadolinium curve (IAUGC90\^bn) and measured by median pixel values of the whole prostate. * Determine the test-retest performance, assessed by the RC of diffusion-weighted imaging (DWI) metrics D(t) and measured by median pixel values of the whole prostate. Secondary * Determine the test-retest performance, assessed by RC of K\^trans, IAUGC90\^bn, and D(t), and measured by median pixel values of the dominant prostate tumor. * Determine the effect of reader on the RC of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and DWI metrics for whole prostate and tumor nodule target lesion. * Determine whether T1-dependent or T1-independent methods for gadolinium quantification in DCE-MRI studies produce differing values for the RC for K\^trans and IAUGC90\^bn. * Explore the correlation between DCE-MRI and DWI metrics for both whole prostate and dominant tumor nodule as target lesions. (Exploratory) * Determine whether the "coffee break" approach toward test-retest analysis of quantitative DWI provides a reasonable estimate of the RC of D(t)of the whole prostate, using as the gold standard the RC of D(t) obtained between the two separate MRI visits. (Exploratory) OUTLINE: This is a multicenter study. Patients are stratified according to MRI vendor used (Siemens vs GE vs Philips). Patients receive gadolinium-based contrast IV and undergo DCE-MRI\* and DWI 2 imaging at 2-14 days apart prior to treatment initiation. A central reader evaluation of the 2 successive scans is then conducted. NOTE: \*At the discretion of the participating sites, the initial MRI visit (MRI SCAN 1) may be supplemented with endorectal-coil imaging per institutional norms.