Post-HIFU surveillance of localized prostate cancer: role of PSMA-PET imaging versus the standard PSA-mpMRI protocol.

INTRODUCTION: Intermediate-risk prostate cancer (PCa) is a heterogeneous subgroup for which the optimal treatment strategy remains a subject of debate. Of all the emerging options, high-intensity focused ultrasound (HIFU) therapy aims to treat the tumor while preserving healthy prostate structures. However, the post-treatment surveillance protocol remains poorly defined, particularly due to the limitations of PSA testing and conventional imaging. This narrative review evaluates the contribution of PSMA-PET metabolic imaging in post-HIFU follow-up compared to standard techniques (PSA, multiparametric MRI). METHODS: A narrative review of the literature was conducted in the Medline, PubMed, and Cochrane (2008-2025) databases. Studies evaluating post-HIFU follow-up by PSA, mpMRI, and/or PSMA-PET were included. Data were analyzed descriptively and critically by two independent reviewers. RESULTS: Eight studies were included out of the 1245 identified articles. Although mpMRI is currently standard, its sensitivity and specificity in the treated area is limited due to post-HIFU anatomical changes. The recently developed PI-FAB score improves the standardization of interpretation but remains operator-dependent. On the other hand, PSMA-PET offers excellent specificity (100%) and satisfactory sensitivity in detecting occult recurrences, even when PSA levels are low and including after mpMRI and systematic biopsies have failed. CONCLUSION: PSMA-PET is a molecular imaging modality that appears promising for post-HIFU surveillance of favorable intermediate-risk prostate cancer. As a complement to PSA testing and multiparametric MRI, it can refine the detection and localization of recurrences and, in doing so, influence the selection and sequencing of salvage therapies in routine practice. Prospective studies are still needed to establish its impact on treatment decision-making and long-term oncologic outcomes.