Introduction: To investigate the relative efficacy of high-frequency 29 MHz transrectal micro-ultrasound (“micro-US”) to conventional low-frequency 7–12 MHz transrectal ultrasound (“conv-US”) in men with self-reported family history of prostate cancer.
Methods: 1,676 men indicated for prostate biopsy and without known prostate cancer were randomized 1:1 to micro-US or conv-US guided biopsy at 5 sites in North America from 2013-16. Exactly 12-cores were taken transrectally from each subject, with each core taken either systematically or from a target near the systematic position. Clinically significant prostate cancer was defined as any Gleason Grade Group > 1 and/or any core with > 50% cancer.
Results: 203/839 (24%) men in the conv-US arm and 180/837 (22%) in the micro-US arm presented with positive family history. The rate of clinically significant cancer in the micro-US arm was significantly higher than in the conv-US arm (43% vs. 30% p=0.004). This relative improvement of 45% is higher than the relative improvement seen over the full per protocol population (19%). These men tended to have a lower risk profile, with lower PSA (5.4 vs 6.2 p<0.001) and age (61 vs 64 p<0.001) in the family history group than the non-family history group. However, there were no significant differences in age or PSA between the family history positive conv-US or micro-US groups (PSA p=0.31, age p=0.76).
Conclusions: First generation transrectal micro-US detected more significant prostate cancers than conventional TRUS in the family history population. This improvement was higher than that seen over the full population. This greater cancer detection rate achieved with the same number of biopsy samples suggests that the accuracy of micro-ultrasound targeting was improved in these men, however it is not clear whether this improvement was due to genetically inherited cancers appearing more prominently on imaging, or improved visualization of smaller prostates in younger men. Further work will be required to confirm this phenomenon and identify the causes. Source of