This single-center study will enroll 40 male participants to complete 2 diffusion magnetic resonance images within 30 days of each other.

Participants will undergo prostate MRI using a range of b-values and echo times. 40 participants will be invited to complete two such scans within 30 days of each other to evaluate reliability across time. Several advanced MRI models will be applied to the data, and the models will be assessed for accurate prediction of grade group ≥2 prostate cancer on histopathology, obtained through routine clinical care. We hypothesize that advanced, multi-compartment dMRI will yield a reliable, quantitative metric that is superior to standard ADC for detection of csPCa.

RSI is a multicompartment model of diffusion MRI that uses data acquired at multiple b-values to distinguish varied diffusion speeds (restricted intracellular, hindered extracellular, and approximately free diffusion). The relative contributions of each compartment are estimated for each voxel in the imaging field of view. RSI cellularity index is a normalized parameter reflecting the contribution of very slow diffusion that is associated with tumor cellularity.

Inclusion Criteria:

• Male, aged ≥18 years, with histologically confirmed adenocarcinoma of the prostate
• Has already undergone prostate MRI and/or scheduled to undergo clinically indicated radical prostatectomy (to permit whole-mount histopathology correlation).
• Intended treatment and follow-up according to standard of care for prostate cancer
• In good general health as evidenced by medical history and ECOG performance status 0-2
• Provision of signed and dated informed consent form
• Stated willingness to comply with all study procedures and availability for the duration of the study

Exclusion Criteria:

• Prior treatment for prostate cancer (cryotherapy, high frequency focused ultrasound, prostatectomy)
• Hip prosthesis
• Contraindication to MRI, per institutional requirements
• Patient has a history or current evidence of any condition, therapy, or laboratory abnormality that might confound the results of the trial, interfere with the subject's participation for the full duration of the trial, or is not in the best interest of the subject to participate, in the opinion of the treating investigator.

biological males with intact prostate

Adult male patients with fair to good performance status and who (1) have undergone an MRI of the prostate for suspected or known prostate cancer and/or (2) are planning to undergo radical prostatectomy for prostate cancer.