Impact of Ultrasound and MRI Visibility of Prostate Cancer on Focal Therapy Outcomes

This study evaluates the oncological outcomes of focal therapy (FT) for prostate cancer (PCa) based on the visibility of tumors on magnetic resonance imaging (MRI). We analyzed a cohort of consecutive patients who underwent MRI-informed prostate biopsy (PBx) followed by either hemi-gland Cryoablation (CRYO) or High-Intensity Focused Ultrasound (HIFU) from a multicentric database. Surveillance after FT involved regular PSA testing, annual MRIs, and mandatory follow-up PBx at 12 months and biennially thereafter. Lesion visibility was defined according to the Prostate Imaging-Reporting and Data System (PIRADS) score of ≥4. The primary endpoint was treatment failure (TF), characterized by Grade Group (GG) ≥2 on follow-up PBx, any whole-gland treatment, systemic therapy, metastases, or prostate cancer-specific mortality. Secondary endpoints included survival rates free from biochemical failure (BF), GG≥2 on follow-up PBx, and radical treatment. Out of 156 patients, 97 (62%) had visible PCa on baseline MRI, with these patients being older and having higher PSA density compared to those with invisible tumors. The 3-year survival rates indicated that patients with visible tumors had significantly higher TF rates (57% vs. 82%, p=0.004) and GG≥2 on follow-up PBx (58% vs. 84%, p=0.003). Lesion visibility, PSA density, and nadir PSA reduction emerged as independent predictors of treatment failure. In conclusion, patients with MRI-visible PCa face an increased risk of treatment failure following focal therapy, suggesting that MRI visibility could serve as a valuable prognostic tool in managing PCa.