Dataset related to article "PSMA-PET/CT for response assessment in localised prostate cancer treated with HIFU: a biopsy-validated study"

Purpose. High-intensity focused ultrasound (HIFU) is being investigated as a tissue-preserving treatment for localized prostate cancer. Response assessment remains challenging because prostate-specific antigen (PSA) kinetics may not accurately reflect local tumour status. In this study, we evaluated visual and semiquantitative prostate-specific membrane antigen (PSMA) PET/CT findings before and after HIFU to identify the imaging parameter most informative for predicting post-treatment biopsy outcome. Methods. Between 2020 and 2024, 68 patients enrolled in the Focal Therapy for Organ-Confined Prostate Cancer study underwent HIFU, baseline and post-treatment PSMA PET/CT, and post-HIFU biopsy. Visual findings, SUVmax, SUVmean, background-normalized uptake ratios, and PSA changes were assessed. Biopsy served as the reference standard. Diagnostic performance was evaluated using standard metrics, receiver operating characteristic analysis, and exploratory logistic regression incorporating post-treatment SUVmax and baseline tumour grade. Results. Post-HIFU biopsy was positive in 45 of 68 patients (66.2%). PSA-derived variables showed limited discrimination of biopsy outcome, with areas under the curve (AUCs) ≤0.63. Visual post-treatment PET/CT showed an AUC of 0.65. Post-treatment SUVmax showed the highest discrimination among individual continuous parameters (AUC, 0.75). Compared with visual PET assessment, a post-treatment SUVmax threshold of 5.23 g/mL reduced false-positive findings but increased false-negative findings. Exploratory ISUP-specific SUVmax thresholds of 2.56 g/mL for ISUP grade 1 and 5.34 g/mL for ISUP grade 2 yielded an AUC of 0.76, reducing false-positive findings without increasing false-negative findings relative to visual PET assessment. Conclusion. Post-treatment PSMA PET/CT provides clinically relevant information after HIFU, whereas PSA has limited discriminatory value. SUVmax was the most informative semiquantitative parameter, and its interpretation according to baseline ISUP grade improved the balance between false-positive and false-negative classifications. These findings support an integrated assessment combining visual interpretation, quantitative uptake, and tumour grade to refine post-HIFU risk stratification, while biopsy remains the reference standard. Prospective validation and longer-term longitudinal evaluation are needed.