Likelihood of sampling prostate cancer at systematic biopsy as a function of gland volume and number of cores

Automatic MRI-TRUS Fusion Technique for Transperineal Biopsy Guidance: From Preoperative Planning to Intraoperative Navigation

BACKGROUND

Targeted and systematic transperineal biopsy of lesions guided by magnetic resonance imaging (MRI) and transrectal ultrasonography (TRUS) fusion technique may optimize the biopsy procedure and enhance the detection of prostate cancer. We described the transperineal biopsy guided by an automatic MRI-TRUS fusion technique, and evaluated the accuracy and feasibility of this method in a prospective single-center study.

METHODS

The proposed method focuses on automating the delineation of prostate contours in both the MRI and TRUS images, the registration and fusion of MRI and TRUS images, the generation and visualiztion of the systematic biopsy cores in their corresponding locations within the 2D and the 3D views, as well as the computation and visualiztion of needle trajectories from preoperative planning to intraoperative navigation. A total of 76 patients with clinically suspected prostate cancer underwent systematic (SBx) and targeted (TBx) biopsies, all performed by a single urologist with more than 10 years of experience. The detection rates of prostate cancer (PCa) and clinically significant prostate cancer (csPCa) were recorded. We also measured preoperative registration time, duration of the overall surgical procedure, and postoperative complication rates within the first week following the surgery. Descriptive analyses were presented in this study.

RESULTS

PCa was identified in 73.7% (56/76) of the subjects, while csPCa was identified in 61.8% (47/76). The preoperative registration time was 5.0 min (IQR: 4.4-6.0), while the overall surgery duration was 24.8 min (IQR: 23.2-27.2). Postoperatively, 12 patients experienced immediate hematuria, and one patient reported dysuria 1 day following surgery.

CONCLUSIONS

The automatic MRI-TRUS fusion technique for transperineal biopsy is feasible and safe, with preoperative planning to intraoperative navigation it offering convenient and efficient preoperative preparation and surgical procedure.

Elucidating the need for prostate cancer risk calculators in conjunction with mpMRI in initial risk assessment before prostate biopsy at a tertiary prostate cancer center

OBJECTIVE

Utilizing personalized risk assessment for clinically significant prostate cancer (csPCa) incorporating multiparametric magnetic resonance imaging (mpMRI) reduces biopsies and overdiagnosis. We validated both multi- and univariate risk models in biopsy-naïve men, with and without the inclusion of mpMRI data for csPCa detection.

METHODS

N = 565 men underwent mpMRI-targeted prostate biopsy, and the diagnostic performance of risk calculators (RCs), mpMRI alone, and clinical measures were compared using receiver operating characteristic curve (ROC) analysis and decision curve analysis (DCA). Subgroups were stratified based on mpMRI findings and quality.

RESULTS

csPCa was detected in 56.3%. PI-RADS score achieved the highest area under the curve (AUC) when comparing univariate risk models (AUC 0.82, p < 0.001). Multivariate RCs showed only marginal improvement in csPCa detection compared to PI-RADS score alone, with just one of four RCs showing significant superiority. In mpMRI-negative cases, the non-MRI-based RC performed best (AUC 0.80, p = 0.016), with the potential to spare biopsies for 23%. PSA-density and multivariate RCs demonstrated comparable performance for PI-RADS 3 constellation (AUC 0.65 vs. 0.60-0.65, p > 0.5; saved biopsies 16%). In men with suspicious mpMRI, both mpMRI-based RCs and the PI-RADS score predicted csPCa excellently (AUC 0.82-0.79 vs. 0.80, p > 0.05), highlighting superior performance compared to non-MRI-based models (all p < 0.002). Quality-assured imaging consistently improved csPCa risk stratification across all subgroups.

CONCLUSION

In tertiary centers serving a high-risk population, high-quality mpMRI provides a simple yet effective way to assess the risk of csPCa. Using multivariate RCs reduces multiple biopsies, especially in mpMRI-negative and PI-RADS 3 constellation.