Impact of a novel biopsy instrument with a 25-mm side-notch needle on the detection of prostate cancer in transrectal biopsy

Implications of a Novel Biopsy Downloading System on Prostate Cancer Detection Rate, Surveillance and Focal Therapy - A Prospective Study

OBJECTIVE

To examine the SmartBx, a novel biopsy downloading system, allowing downloading of biopsy cores with maximal core preservation as prostate biopsy sampling lacks preservation of core configuration & orientation.

METHODS

We prospectively collected cores from TRUS biopsy patients. Half were collected using the SmartBx & half using standard downloading. We measured length of the first ∼3200 cores through various pathology steps and within core cancer length in 160 SmartBx cores. We compared core length, yield (% of core available for final analysis/ original core on needle) and cancer detection rate between SmartBx and standard cores. T-test or chi-square were used for analysis.

RESULTS

6014 cores were collected from 429 patients. Core length (12.3mm vs. 10mm; P<.01) and core yield (77.5% vs. 62.2%; P<.01) were significantly higher using the SmartBx compared to standard method, respectively. Cancer detection rate was significantly higher using the SmartBx for patients with PSA<10 (10.1% vs. 7.96%; n=2080 & n=2073, respectively; P<.016). Other subgroups showed non-significant higher detection rate for SmartBx cores. We noticed higher detection rate of clinically significant prostate cancer. Within core cancer length in 160 SmartBx cores was significantly lower compared to standard positive whole cores (4.45mm vs. 10.9mm; P<.001). Assuming cancer site a perfect sphere, disease volume was 11-fold lower for within core compared to entire core (46.1mm vs. 679.9mm; P<.0001).

CONCLUSIONS

SmartBx results in significant higher core length, yield and cancer detection rate. Precise localization of within core tumor foci allows significant reduction in tumor volume.