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The impact of biopsy approach on the detection rate of prostate cancer (PCa) is an active area of investigation. While recent evidence suggests higher cancer detection rates for targeted biopsies using a transperineal approach, the impact of lesion location remains unclear. This study aims to investigate the relative performance of transperineal (TP) MRI-targeted prostate biopsy (TBx) for the detection of clinically significant prostate cancer (csPCa) in the apex, compared to transrectal (TR) TBx. A prospectively maintained database of patients who underwent MRI-guided prostate biopsy at our institution between 2016-2023 was queried for patients with MRI lesions in the apex.;Biopsies were performed using the UroNav MRI/ultrasound fusion biopsy system using an endfire ultrasound probe. Overall cancer detection rate, as well as rate of Gleason grade group (GG) ≥2 and GG≥3, were compared on a per-lesion basis between patients undergoing TP-TBx and patients undergoing TR-TBx. Clinical factors including PSA levels, prostate volume, and the location of the lesion in the apex were assessed using two-sample t-tests and chi-squared tests, and PIRADS scores were compared between groups using the Kruskal-Wallis test. To account for patients who underwent both TP-TBx and TR-TBx, chi-squared tests were conducted to compare the diagnoses for the same patient cohort. Between 2016-2023, 1034 apical prostate lesion biopsies were identified, of which 159 were TP-TBx and 875 were TR-TBx (Table 1). A univariate analysis of pre-biopsy PSA, prostate volume and PIRADS demonstrated no statistically significant difference between the TP-TBx and TR-TBx groups. The rate of ≥GG2 cancers diagnosed was statistically greater for TP-TBx vs TR-TBx (44.26% vs 35.66%, p =0.03). The overall cancer detection rate (CDR) and CDR of cancers ≥ GG 3 were not statistically different between biopsy types. Amongst the sub cohort with available zonal delineation (n = 764), there was a higher CDR of GG>2 cancers in the peripheral zone, but not transition zone (Table 2). Among a subset of patients who underwent TR biopsy followed by TP (n= 34), 35.29% were upgraded on TP biopsy, while 0% of patients who underwent TR after TP biopsy (n= 5) were upgraded on TR biopsy. In this analysis, targeted transperineal biopsy was associated with higher GG≥2 detection rate compared to transrectal biopsy for apical lesions. Prospective studies are warranted to validate transperineal biopsy as a potentially superior approach for prostate cancer detection in apical lesions in the MRI era. [ABSTRACT FROM AUTHOR]

Multiparametric magnetic resonance imaging (mpMRI) has led to improved diagnosis and risk stratification of prostate cancer. The Prostate Imaging Reporting and Data System (PI-RADS) is a widely-adopted standardized interpretation scheme for prostate mpMRI. Lesions are scored 1-5 based on suspicion for clinically significant prostate (csPCa), defined as Grade Group ≥ 2, with increasing positive predictive value indicated by higher score. Multiple studies have demonstrated the positive predictive value of a PI-RADS 5 lesion for csPCa to cluster around 70-80%. Since nearly 80% of those with PI-RADS 5 lesions harbor clinically significant disease on biopsy, many receive upfront therapy. There is limited understanding of what happens to remaining patients with PI-RADS 5 lesions in whom biopsies reveal less aggressive disease. The purpose of this study is to evaluate the clinical course of those with PI-RADS 5 lesions with Grade Group 1 disease who were placed on Active Surveillance (AS). This analysis was limited to AS patients with GG1 prostate cancer on targeted biopsy of a solitary PI-RADS 5 index lesion performed from 2007 to 2022. Each scan was read by a high-volume genitourinary radiologist (BT or PC). These patients underwent systematic and targeted biopsy by physicians experienced with MRI-fusion biopsies (PP, BW, SG). Repeat biopsies were performed based on clinicopathologic concern for progression (rising PSA, MRI changes) or local AS protocols. For MRIs preceding PI-RADS scoring, an internal Likert suspicion scoring system that has been validated in the literature was used and converted into PI-RADS scores. Beginning in 2015, internal mpMRI readings were reported using PI-RADS v2.0 and in 2019 transitioned to PI-RADS v2.1. Biopsy specimens were reviewed by dedicated genitourinary pathologists. Descriptive statistics were performed. Univariate analyses, including independent samples t-test, chi-squared analysis, and Fisher's exact test, were performed to evaluate for factors associated with disease upgrading. 21 patients met inclusion criteria. The mean PSA was 7.9 ng/ml (range 2.4-14.5) (Table 1). At median follow up of 4.3 years, 15/21 (71%) patients progressed to GG≥2 disease, 5 of whom (24% of initial cohort) progressed to GG≥3 (Figure 1). Median time to progression to GG≥2 and GG≥3 was 3.3 years and 4.4 years, respectively. Of the 6 who did not progress, 1 underwent prostatectomy (upgraded to GG2 on final pathology) and 5 were maintained on AS. Of the 16 who progressed to GG≥2, 6/21 (29%) were continued on AS. 5 of these patients remained on AS (median follow-up 3.3 years after progression) and one underwent prostatectomy. Overall, 11 (52%) received definitive therapy. On univariate analysis, only mean maximum cancer core length was associated with progression to radical therapy (4.8 vs 8.0 mm, p=0.048). Patients with PI-RADS 5 lesions and GG1 PCa on AS demonstrate a rate of upgrading to GG≥2 of >70% and nearly a quarter were upgraded to GG≥3. Nearly 50% of patients progressed to radical treatment at 4 years. This represents a high rate of upgrading in a short period of time relative to larger AS series, which place pathologic upgrading at 25-50%. Further studies, including longer-term follow-up, will be necessary. Genomic classification of these initially indolent lesions may provide clarity regarding the best management. The question of how our findings should affect practice is important. With half of patients suitable for AS at follow-up, it is reasonable to continue AS as the preferred management. However, there is a higher risk of requiring intervention and these patients should be counseled and monitored accordingly. While focal therapy is not guideline-endorsed for GG1 disease, this may be a population that could benefit. [ABSTRACT FROM AUTHOR]

The advent of multiparametric magnetic resonance imaging (mpMRI) has helped to localize clinically significant prostate cancer (csPCA). Focal Therapy (FT) has emerged in the mpMRI era, which can treat MRI-visible lesions while avoiding side effects of whole-gland treatment. However, FT remains an investigational treatment option for PCa patients with intermediate-risk disease. Little is known about how many patients on active surveillance (AS) with Gleason grade group (GG) 2 disease retain eligibility for FT over time, or risk factors for loss of eligibility. The objective of this study is to evaluate initial and long-term FT eligibility (FTE) of patients with GG2 disease. A prospectively maintained cohort was retrospectively queried for patients initiated on AS between 2007;and 2020 with GG2 PCa. Patients with biopsy-concordant GG2, unilateral, MRI-visible PIRADS 2-5 lesions amenable to hemiablation were considered FT candidates. Those with PSA>20 ng/mL, >4 MRI lesions, bilateral (BL) MRI-visible/biopsy-concordant lesions, or contralateral GG≥2 PCa or MRI-invisible lesions were excluded. Patients were considered to progress if they developed BL GG≥2 disease or unilateral GG≥3 PCa. Patients without GG progression maintained FTE and those with GG progression maintained FTE if they had unilateral biopsy-concordant/MRI-visible GG≤3, no contralateral GG≥2 disease, and PSA<20 ng/mL. Univariate and multivariate analyses were conducted to compare patients who maintained and lost FTE. 252 PCa patients were identified as eligible for FT with an average follow-up of 3.4 years, 83 of whom (33%) had GG2 disease and were FT candidates. 29/83 (35%) lost FT eligibility, 19/83 (23%) with progression to high-risk disease, 6/83 (7.2%) due to development of BL GG≥2 disease, and 4/83 (4.8%) with development of MRI-invisible csPCA. Baseline characteristics are shown in Table 1. Univariate analysis demonstrated that those who lost FTE had smaller prostates than those who maintained it (44.9 mL vs. 56.2mL, respectively, p=0.018). PSA density was similar between the groups. No significant differences were noted in initial imaging and pathologic parameters. No factors significantly associated with loss of FTE were identified on logistic regression (Table 2). 33% of the patients on AS had GG2 disease and were initially eligible for FT. 65% of patients with GG2 disease were still eligible for FT after a median follow up of 3.4 years; over one third of these patients lose FTE. This data regarding the loss of a FT therapeutic window could prove useful in counseling GG2 patients considering AS, FT, or radical treatment. [ABSTRACT FROM AUTHOR]

The introduction of multiparametric magnetic resonance imaging (mpMRI) has significantly improved the early detection of clinically significant prostate cancer. The use of mpMRI has enabled more precise disease characterization, enabling improved risk stratification and candidate selection for active surveillance (AS). However, little is known about the clinical outcomes associated with small mpMRI lesions, which may be associated with low tumor burden and a potentially less aggressive course. This study aims to define the rates of prostate cancer progression and radical therapy for patients on AS with small index lesions and to explore the relationship between index lesion growth rates and cancer progression. A prospectively maintained database of patients on active surveillance at the National Cancer Institute was queried for patients with mpMRI index lesions ≤7mm in greatest diameter who had ≥2 mpMRIs and MRI-Ultrasound fusion biopsy sessions. Patients were identified with mpMRI lesions confirmed on MRI/Ultrasound fusion biopsy to have no worse than Gleason grade group (GG) 1 prostatic adenocarcinoma. Index lesions were defined as the MRI lesions with the highest PI-RADS score, with size used as a tiebreaker. For MRIs preceding PI-RADS scoring, an internal Likert suspicion scoring system that has been validated in the literature was used and converted into PI-RADS scores. MR review was conducted by a high-volume dedicated genitourinary radiologist.;Time to GG progression was calculated to be the difference between initial mpMRI and mpMRI at the time of cancer progression. Between 2007-2022, patients on AS with small index lesions measuring ≤7 mm (n=88) were identified. 26.53% of patients whose index lesions which grew between 0 and 1 mm/year (13/49) progressed to GG2 disease, with an average time to progression of 5.28 years. Of these patients, 12.24% (6/49) progressed to radical therapy, on average 6.16 years after initiating AS (Table 1). Eight years after initial mpMRI, 28.41% of patients in the full cohort (25/88) progressed to radical therapy (Figure 1). Overall, only 5.68% (5/88) of patients developed GG3 disease within 2 years of follow-up, and 2.27% (2/88) progressed to radical therapy. Our findings have important implications for timing of follow-up for patients on AS with small index lesions. The low rate of clinical progression to GG2 disease and radical therapy indicates a less aggressive clinical course than prior published AS series in the pre-MRI era. The presence of small index lesions;may therefore be considered as a favorable marker for determining eligibility and risk of progression for patients considering AS and may guide the timing of repeat imaging to personalize surveillance strategies. [ABSTRACT FROM AUTHOR]