ORLANDO, FL USA (UroToday.com) - In men suspected of having prostate cancer, the current standard is ultrasound-guided template 12-core biopsy to determine the grade and relative burden of disease. However, this procedure has its pitfalls: up to one-third of men have higher grade disease found at radical prostatectomy. Multiple studies over the past several years have demonstrated that MRI-ultrasound fusion-guided biopsy, which layers previously obtained MRI data over a real-time ultrasound image, allows for targeting of lesions in the prostate and is more accurate than 12-core biopsy. While an eventual aim might be for targeted biopsy to supplement or even replace template biopsy, the major limitation of these studies is a lack of comparison of the targeted biopsy results to final pathology. The accuracy of preoperative histology is an essential component of treatment planning – specifically in patients who are candidates for active surveillance. In a six-year analysis of men who underwent radical prostatectomy at the National Cancer Institute, Dr. Arvin George and colleagues sought to evaluate the performance of targeted biopsy and standard 12-core biopsy as compared to the definitive pathology obtained after surgery.
The authors prospectively collected data on patients who underwent MR-ultrasound fusion and standard 12-core biopsies in the same session, and who subsequently went on to have radical prostatectomy. Cancers detected by either biopsy method and on final surgical pathology were compared in terms of the overall Gleason sum. Nearly one-half of template 12-core biopsies undergraded cancer compared to 32% of MRI-ultrasound fusion biopsies. This difference was more pronounced when accounting for high-grade disease, with 53% of 12-core biopsies being upgraded to Gleason ≥ 8, almost double the rate of targeted biopsy. These findings demonstrate that MRI-ultrasound fusion biopsy is more representative of the Gleason grade. Though upgrading still occurred from targeted biopsy to final pathology, this study may herald further acceptance of targeted prostate biopsy as a potential adjunct or successor to standard 12-core biopsy.
Presented by Arvin George at the American Urological Association (AUA) Annual Meeting - May 16 - 21, 2014 - Orlando, Florida USA
National Cancer Institute (NCI), Bethesda, MD USA
Written by Nabeel A. Shakir and Zhamshid Okhunov, University of California (Irvine), and medical writers for UroToday.com