BACKGROUND: This study aimed to investigate the number of cores needed in a systematic biopsy (SB) in men with clinical suspicion of prostate cancer (PCa) but negative prebiopsy multiparametric magnetic resonance imaging and to test prostate-specific antigen (PSA) density as an indicator for reduced SB.
METHODS: Two hundred and seventy-four patients were analyzed, extracted from an institutional database. Detection rates of any PCa and clinically significant (CS) PCa for different reduced biopsy protocols were compared by using Fisher\'s exact test.
RESULTS: In total, 12-core SB revealed PCa in 103 (37.6%) men. Detection rates of reduced biopsy protocols were 74 (27%, 6-core) and 82 (29.9%, 8-core). Regarding CSPCa, 12-core SB revealed a detection rate of 26 (9.5%). Reduced biopsy protocols detected less CSPCa: 15 (5.5%) and 18 (6.6%), respectively. All differences were statistically significant, p < 0.05. PSA density ≥0.15 did not help to filter out men in whom a reduced biopsy may be sufficient.
CONCLUSIONS: Twelve-core SB still has the highest detection rate of any PCa and CSPCa compared to reduced biopsy protocols. If the investigator and patient agree - based on individual risk calculation - to perform a biopsy, this SB should contain at least 12 cores regardless of PSA density.

BACKGROUND: There are limited data on the learning curve of magnetic resonance imaging/transrectal ultrasound (MRI/TRUS)-fusion targeted prostate biopsies (tBx).
OBJECTIVE: The aim of this study was to investigate the difference in prostate cancer (PCa) detection rate between an experienced urologist and novice resident performing tBx.
METHODS: A total of 183 patients underwent tBx from 2012 to 2016 for a total of 518 tBx cores. Biopsies in this study were performed by an experienced urologist (investigator A) or a novice resident (investigator B). The outcome was the detection of PCa on tBx. Using a multivariable logistic regression model, we estimated odds ratios for the detection of PCa. Inverse probability treatment weighting (IPTW) was used to balance patients\' baseline characteristics and compare detection rates of PCa. Before performance of tBx, all patients underwent MRI.
RESULTS: On multivariable logistic regression analysis, investigator experience was associated with a higher odds of detection of PCa (OR = 1.003; 95% confidence interval 1.002-1.006, p = 0.037). After IPTW adjustment, there was no significant difference between the detection rate of investigator A (23%) and investigator B (32%; p = 0.457).
CONCLUSIONS: Data revealed a positive association between investigator experience and the odds of PCa detection, although there was no difference in the detection rates of the investigators.