• Biopsy-proven adenocarcinoma of the prostate. Biopsy may be performed outside of University of California, San Francisco (UCSF), if detailed results of sextant biopsy are available. For Cohort A only, a minimum of 20 participants out of a planned enrollment of 50 patients must have high-risk disease as defined by primary Gleason score of 4 or 5 on prior prostate biopsy.
• Cohort A only: Planned radical prostatectomy at UCSF within 12 weeks following protocol MRI/MRSI.
• Cohort B only: HIFU focal therapy completed within 18 months of protocol MRI/MRSI, and planned systematic and MR-guided biopsy at UCSF within 12 weeks following protocol MRI/MRSI.
• The participant is able and willing to comply with study procedures and provide signed and dated informed consent
• Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1

• Participants who because of age less than 18 years old, general medical or psychiatric condition, or physiologic status cannot give valid informed consent.
• Participants unwilling or unable to undergo MR imaging, including patients with contraindications to MRI, such as cardiac pacemakers or non-compatible intracranial vascular clips.
• Participants who cannot tolerate or have contra-indications to endorectal coil insertion; for example, participants with a prior abdominoperineal resection of the rectum or latex allergy.

Note: The use of an endorectal coil may be waived at the discretion of the Principal Investigator upon review of available imaging with radiology, in which case this exclusion criterion will not apply.

• Patients with contra-indications to injection of gadolinium contrast; for example patients with prior documented allergy or those with inadequate renal function.
• Metallic hip implant or any other metallic implant or device that distorts local magnetic field and compromises the quality of MR imaging.
• Cryosurgery, surgery for prostate cancer, prostatic or pelvic radiotherapy prior to study enrollment. For Cohort B, HIFU focal therapy is allowed. No limit on number of prior prostate biopsies; prior transurethral prostatic resection (TURP) is not allowed.
• Current or prior androgen deprivation therapy. For Cohort A, a history of use of a 5-alpha reductase inhibitor is allowed, provided it was discontinued at least one month prior to study entry. For cohort B, a history of use of 5-α reductase inhibitor is allowed, provided it is discontinued at least 14 days to protocol MRI/MRSI.
• Poorly controlled hypertension, with blood pressure at study entry > 160/100; the addition of anti-hypertensives to control blood pressure is allowed for eligibility determination.
• Congestive heart failure or New York Heart Association (NYHA) status >= 2.
• A history of clinically significant electrocardiography (EKG) abnormalities, including QT prolongation, a family history of prolonged QT interval syndrome, or myocardial infarction (MI) within 6 months of study entry; patients with rate-controlled atrial fibrillation/flutter will be allowed on study.