Focal Therapy Eligibility Determined by Magnetic Resonance Imaging/Ultrasound Fusion Biopsy

We assessed focal therapy eligibility in men who underwent multiparametric magnetic resonance imaging and targeted biopsy with correlation to whole mount histology after radical prostatectomy.

Subjects were selected from among the 454 men in whom targeted biopsy-proven prostate cancer was derived from regions of interest on multiparametric magnetic resonance imaging from 2010 to 2016. Focal therapy eligibility was limited to a maximum Gleason score of 4 þ 3 in regions of interest with or without other foci of low-risk prostate cancer (Gleason score 3 þ 3 and less than 4 mm). Men who did not meet NCCN! intermediate risk criteria were classified as ineligible for focal therapy. Of the 454 men, 64 underwent radical prostatectomy and biopsy findings were compared to final pathology findings. 

Of the 454 men with a biopsy-proven region of interest 175 (38.5%) were eligible for focal therapy. Fusion biopsy, which combined targeted and template biopsy, had 80.0% sensitivity (12 of 15 cases), 73.5% specificity (36 of 49) and 75.0% accuracy (48 of 64) for focal therapy eligibility. Targeted cores alone yielded 73.3% sensitivity (11 of 15 cases), 47.9% specificity (23 of 48) and 54.7% accuracy (35 of 64). Gleason score and extension across the midline differed in 4 and 9, respectively, of the 13 cases that showed discordant biopsy and whole mount histology. 

Using intermediate risk eligibility criteria more than a third of men with a targeted biopsy proven lesion identified on multiparametric magnetic resonance imaging would have been eligible for focal therapy. Eligibility determined by fusion biopsy was concordant with whole mount histology in 75% of cases. Improved selection criteria are needed to reliably determine focal therapy eligibility.

Nima Nassiri, Edward Chang, Patricia Lieu, Alan M. Priester, Daniel J. A. Margolis, Jiaoti Huang, Robert E. Reiter, Frederick J. Dorey, Leonard S. Marks and Shyam Natarajan
From the Department of Urology, David Geffen School of Medicine (NN, EC, PL, RER, FJD, LSM) and Department of Bioengineering (AMP), University of California-Los Angeles (SN), Los Angeles, California, Department of Radiology, Weill Cornell at New York Presbyterian (DJAM), New York, New York, and Department of Pathology, Duke University School of Medicine (JH), Durham, North Carolina

J Urol. 2018 Feb;199(2):453-458. doi: 10.1016/j.juro.2017.08.085. Epub 2017 Aug 19.