Diagnostic accuracy and clinical implications of robotic assisted MRI-US fusion guided target saturation biopsy of the prostate

MRI-targeted prostate biopsy improves detection of clinically significant prostate cancer (PCa). However, up to 70% of PCa lesions display intralesional tumor heterogeneity. Current target sampling strategies do not yet adequately account for this finding. This prospective study included 118 patients who underwent transperineal robotic assisted biopsy of the prostate. We identified a total of 58 PCa-positive PI-RADS lesions. We compared diagnostic accuracy of a target-saturation biopsy strategy to accuracy of single, two, or three randomly selected targeted biopsy cores and analysed potential clinical implications. Intralesional detection of clinically significant cancer (ISUP ≥ 2) was 78.3% for target-saturation biopsy and 39.1%, 52.2%, and 67.4% for one, two, and three targeted cores, respectively. Target-saturation biopsies led to a more accurate characterization of PCa in terms of Gleason score and reduced rates of significant cancer missed. Compared to one, two, and three targeted biopsy cores, target-saturation biopsies led to intensified staging procedures in 21.7%, 10.9, and 8.7% of patients, and ultimately to a potential change in therapy in 39.1%, 26.1%, and 10.9% of patients. This work presents the concept of robotic-assisted target saturation biopsy. This technique has the potential to improve diagnostic accuracy and thus individual staging procedures and treatment decisions.

Robotic Assisted MRI-US Fusion Guided Target Saturation Biopsy of the Prostate – Diagnostic Accuracy and Clinical Implications

MRI-targeted prostate biopsy improves detection of clinically significant prostate cancer (PCa). However, up to 70% of PCa lesions display intralesional tumor heterogeneity. Current target sampling strategies do not yet adequately account for this finding. This prospective study included 118 patients who underwent transperineal robotic assisted biopsy of the prostate. We identified a total of 58 PCa-positive PI-RADS lesions. We compared diagnostic accuracy of a target-saturation biopsy strategy to accuracy of single, two, or three randomly selected targeted biopsies and analysed potential clinical implications. Intralesional detection of clinically significant cancer (ISUP ≥ 2) was 78.3% for target-saturation biopsy and 39.1%, 52.2%, and 67.4% for one, two, and three targeted cores, respectively. Target-saturation biopsies led to a more accurate characterization of PCa in terms of Gleason score and reduced rates of missed cancer. Compared to one, two, and three targeted biopsies, target-saturation biopsies led to intensified staging procedures in 21.7%, 10.9, and 8.7% of patients, and ultimately to a potential change in therapy in 39.1%, 26.1%, and 10.9% of patients. This work presents the concept of robotic-assisted target saturation biopsy. This technique has the potential to improve diagnostic accuracy and thus individual staging procedures and treatment decisions.

Rate of clinically significant prostate cancer on repeat saturation biopsy after a diagnosis of atypical small acinar proliferation

Background: Atypical small acinar proliferation (ASAP) occurs in approximately 5% of prostate biopsies. Approximately 30%–40% of these patients may develop prostate cancer (PCa) within a 5-year period, often not clinically significant. Current guidelines recommend a repeat biopsy within 3–6 months after the initial diagnosis, but it seem not to be the best strategy. Methods: Objectives—evaluating the natural history of ASAP, stratifying the risk of csPCa after ASAP, identifying predictive factors of PCa after atypical diagnosis. Materials and methods—retrospective single-institutional study on patients undergoing prostate biopsy for suspicious PCa (2005–2016). We evaluated the incidence of overall PCa, intermediate-high risk of PCa and csPCa in case of ASAP, according to D’Amico classification and Epstein modified criteria. Results: Out of 4.567 patients undergoing prostate biopsy, ASAP was detected in 2.6% of cases. All patients with ASAP underwent repeat saturation biopsy within 6 months and PCa was diagnosed in 34.5%. According to D’Amico classification, 26%, 5.9%, and 2.5% had low, intermediate, and high-risk disease, respectively. According modified Epstein criteria, the incidence of csPCa was 12.6%. LRT showed that the overall probability to develop PCa doubled when PSA density (PSAD) moved from values lower than 0.13 ng/ml/cc to class 0.13–0.30 ng/ml/cc, and it tripled when PSAD was higher than 0.30 ng/ml/cc. Conclusions: The rate of csPCa in patients with an initial diagnosis of ASAP who had repeat biopsy was 12.6%. The overall PCa rate was 34.5%. Among patient undergoing RP, an upgrading from ncsPCa to csPCa was reported in 35% of cases. PSAD is the only predictive factor directly associated to the risk of developing PCa on repeat biopsy. These findings suggest that immediate repeat biopsy remains the correct strategy in absence of novel predictor factors and non-invasive diagnostic evaluations.