経会陰前立腺MRI-TRUS融合画像ガイド下生検の導入期における診断精度の検討

Abstract

Magnetic resonance imaging (MRI) ultrasound fusion biopsy is becoming popular owing to the better detection rate of clinically significant prostate cancer (csPCa). We retrospectively evaluated the accuracy of MRI-targeted biopsy during the period of introduction at a single academic center by comparing findings of its specimen and whole-mount histopathology. Between June 2018 and January 2021, 106 transperineal MRI-ultrasound fusion biopsies using BioJet software were performed. Among the cases, 15 subsequently underwent robotic-assisted laparoscopic radical prostatectomy and were eligible for analysis. This study included all regions of interest (ROIs) with a Prostate Imaging Reporting and Data System v2 category of 3 or greater on pre-biopsy MRI．For each lesion, grade group of MRI-targeted biopsy specimens and prostatectomy specimens were compared. From a total of 25 ROIs identified among 15 males, csPCa was found in 21 (84%) of the concordant locations of prostatectomy specimens. However, MRI-targeted biopsy could diagnose csPCa in only 12 (48%) of them. In the csPCa undetected group, the ROI volume was significantly smaller (median volume 0.23 ml vs 0.40 ml, p＝0.03). We also found that in cases where PCa was not detected through MRI-targeted biopsy, the biopsy sample length was significantly shorter (median length 9 mm vs 17 mm, p＝0.01). Our data suggest that failure of detecting PCa in MRI-targeted biopsy could be due to technical errors at the introduction period of the technique. A sufficient sampling length of 10 mm or more is desirable, especially for small lesions.