The purpose of this study is to compare the sensitivity of PSMA PET/MRI and standard MRI in detecting focal therapy failure in the prostate one year after High-Intensity Focused Ultrasound (HIFU) treatment. Specifically, the study aims to evaluate whether PSMA PET/MRI offers a higher sensitivity than MRI alone for identifying recurrence or failure in patients undergoing focal therapy.

Inclusion Criteria:

• Male patients 40-95 years of age with biopsy-confirmed localized prostate cancer.
• Grade Group ≥2 (Gleason score 3+4 or higher).
• Unifocal disease visible on mpMRI.
• Patients undergoing HIFU as part of their standard of care
• PSA <20 ng/mL.
• No metastatic disease on PSMA PET/CT
• Willingness to comply with follow-up protocols (PSA testing, imaging, biopsies).

Exclusion Criteria:

• Evidence of metastatic disease on PSMA PET/CT.
• Allergy to POSLUMA or gadolinium.
• Inability to tolerate MRI due to claustrophobia or posture/back-hip issues.

Only male patients will be included in this study. The expected age range will be 40-95. There is no enrollment restrictions based upon race or ethnic origin.

The de-identified participant data from the final research dataset will be shared upon reasonable request beginning 9 to 36 months after publication or as required by a condition of awards or supporting agreements, provided the requesting investigator executes a data use agreement with NYU Langone Health. This instance of data sharing will also require separate IRB review as well as review from NYU Langone's Data Sharing Strategy Board (DSSB). Requests should be directed to: weiphin.tan@nyulangone.org. The protocol and statistical analysis plan will be posted on Clinicaltrials.gov only as required by federal regulation or supporting awards and agreements.

Beginning 9 months and ending 36 months following article publication or as required by a condition of awards and agreements supporting the research.

The investigator who proposed to use the data will be granted access upon reasonable request. Requests should be directed to weiphin.tan@nyulangone.org. To gain access, data requestors will need to sign a data access agreement. This instance of data sharing will also require separate IRB review as well as review from NYU Langone's DSSB.