Significance of non-standardized magnetic resonance imaging abnormalities and subsequent targeted prostate cancer...

Prostate biopsy is essential in diagnosing prostate cancer. The Prostate Imaging-Reporting and Data System (PI-RADS) and magnetic resonance imaging (MRI)-transrectal ultrasound fusion-guided biopsy are also useful for diagnosis. However, the burden of implementing and maintaining these techniques should be considered. Therefore, we investigated the significance of non-standardized pre-biopsy MRI abnormalities (conditions not in accordance with PI-RADS) and subsequent targeted biopsy. We collected clinicopathological data, including the presence or absence of MRI abnormalities, through biopsies from January 2017 to February 2022 at the Kanagawa Cancer Center and performed statistical analyses. We enrolled in 1086 cases: MRI abnormalities were observed in 861 cases (79.3%). In these 861 cases, the adenocarcinoma detection rate, number of positive cores, and length of the highest Grade Group (GG) lesions were significantly higher. In the multivariate analysis, MRI abnormalities were the most significant factor for detecting adenocarcinoma of ≥GG 2 (odds ratio: 4.52, 95% confidence interval: 3.08-6.63). Targeted biopsy showed a higher percentage of positive cores with ≥GG2 and longer highest GG lesion lengths than systematic biopsy. Furthermore, the highest GG was upgraded in 109 of 788 cases by targeted biopsy. However, several adenocarcinomas (125/788; 15.9%) could not be detected using only targeted biopsy. Non-standardized MRI abnormalities are powerful predictors of cancer and grading. Targeted biopsies based on MRI abnormalities provide several benefits. Owing to the relatively low implementation hurdle, these biopsies may serve as a bridge until the ideal approaches are popularized if the limitations are well understood.