Men suspected of having prostate cancer based on rising PSA or abnormal DRE are typically sent for a transrectal ultrasound (TRUS) guided biopsy using 12 or more needles. At least 30% of TRUS biopsies miss the disease that is present, not to mention the possible side effects of the biopsy itself. What happens next?
- The PSA continues to rise.
- In one to two years, the patient is sent for a repeat biopsy.
- Since TRUS biopsy tends to miss certain locations, there’s a good chance that the tumor will again be missed.
- By the time the cancer is found in a second, third or even fourth biopsy, it may have grown in size or increased in aggression.
This routine is about to change, thanks to a collaboration of expert urologists and radiologists. Representatives from the American Urological Association and the Society of Abdominal Radiology formed a panel to review published literature, and arrive at a consensus on a new recommended protocol. The results mean good news for patients who have continued prostate cancer suspicion after an initial negative TRUS biopsy. In such cases, according to the published paper by Rosenkrantz et al. (2016), “If a biopsy is recommended, prostate magnetic resonance imaging and subsequent magnetic resonance imaging targeted cores appear to facilitate the detection of clinically significant disease over standardized repeat biopsy.”[i] Their conclusion was based on consistent research showing that targeted biopsies done under MRI guidance are more effective than standard biopsies for this population. The joint statement recognizes that before a repeat biopsy, multiparametric MRI (mpMRI) reveals the suspicious area, especially when performed on a 3T magnet and interpreted by an expert. The preferred method of interpretation is the PI-RADS assessment score which has shown to be highly accurate. The ultimate impact of this consensus statement will not only improve patient selection for repeat biopsy (higher vs lower PI-RADS scores) but also maximize the diagnostic yield with minimal targeted needles.
The panel cautioned that there is a lack of consistent guidelines on the use of mpMRI, and radiology practices vary in magnet technology, and experience levels for both performing the scan and interpreting the results. Out of concern that less experienced readers may miss a suspicious lesion, the panel recommends, “In patients with negative or low suspicion magnetic resonance imaging (PI-RADS assessment category of 1 or 2, respectively), other ancillary markers (ie PSA, PSAD, PSAV, PCA3, PHI, 4K) may be of value in identifying patients warranting repeat systematic biopsy….”
If a PI-RADS lesion assessed at 3-5 is detected, the panel members concur that a targeted biopsy into the area is warranted, and offers the greatest likelihood of accuracy. They note that if the magnet technology is available, a real time in-bore MRI targeted biopsy “offers the advantage of being the most direct targeting.” This is a vast improvement in locating and diagnosing clinically significant disease that will require swift intervention vs. insignificant disease that may be safely monitored.
Perhaps what is truly noteworthy is the cooperation between urology and radiology, a value long promoted by the Sperling Prostate Center. In fact, our Center has literally “led the charge” when it comes to mpMRI detection, real-time MRI targeted biopsy, and MRI-guided Focal Laser Ablation. We are rightly recognized as pioneering leaders and authorities in each of these areas. As the saying goes, all roads lead to Rome – or in our case, all prostate cancer consensus statements lead to the Sperling Prostate Center.
Our thanks and kudos to the AUA and SAR Prostate Cancer Disease Focused Panel. Interested readers may want to read the full consensus statement, which is available online at http://www.auanet.org/common/pdf/education/clinical-guidance/Consensus-Statement-Prostate-MRI-and-MRI-Targeted-Biopsy.pdf.
[i] Rosenkrantz A, Verma S, Choyke P, Eberhardt SC et al. Prostate Magnetic Resonance Imaging and Magnetic Resonance Imaging Targeted Biopsy in Patients with a Prior Negative Biopsy: A Consensus Statement by AUA and SAR. J Urol. 2016 Dec;196(6):1613-18.