A 62-year-old man presents with a progressively rising serum prostate-specific antigen (PSA) level and two prior negative transrectal ultrasound (TRUS)–guided systematic biopsies (SBs). His brother underwent radical prostatectomy for an intermediate-risk clinically localized prostate cancer. Relevant prior history and evaluation are found in Table 1.
Physical examination revealed a benign 50-g prostate.
A multiparametric magnetic resonance imaging (MRI) scan was obtained. The pertinent image shows a large prostate imaging reporting and data system (PI-RADS) 5 lesion in the left transition zone (Figure 1).
T2-weighted imaging and the diffusion-weighted imaging shows a low signal intensity lesion in the left anterior transition zone. Dynamic contrast enhancement demonstrates early uptake and rapid wash out of the transition zone lesion. There was capsular bulging likely associated with extracapsular extension.
Magnetic resonance fusion-target biopsy (MRFTB) was performed. Four biopsies were directed into the MRI target following coregistration and fusion of the three-dimensional MRI and ultrasound images; 12 SBs were performed using an automatically generated template. Gleason 7 (4+3) prostate cancer was detected in three of four targeted biopsies. The largest core length was 10 mm. All SB results were negative.
A nerve-sparing radical retropubic prostatectomy was performed. Because of the anterior location of the tumor and negative SB result, a nerve-sparing procedure was performed despite the high-risk disease.
Widespread PSA screening coupled with TRUS-guided random SB and aggressive curative treatment has decreased mortality of prostate cancer by over 40%. This impressive decline in mortality has been accomplished at the expense of over-biopsy and overtreatment. The challenge to the urology community is to screen and detect smarter in order to, ultimately, treat smarter. In essence, the goal should be to detect and treat only significant cancers. The definition of significant disease is controversial and depends on the patient’s life expectancy. Most agree that significant disease includes Gleason score > 6 and high-volume Gleason 6 disease.
There is increasing evidence that MRFTB increases detection of significant prostate cancer compared with TRUS-guided SB. For those who have adopted MRFTB, should the SB be performed along with the MRFTB? Our preliminary results suggest the random SB ipsilateral to the MRI target detects a greater proportion of significant disease, whereas the random SB contralateral to the MRI target detects almost exclusively insignificant disease. This is consistent with a high negative predictive value of multiparametric MRI for significant disease.
Should the multiparametric MRI be performed prior to the first biopsy or only if the PSA value persistently rises after a negative SB result? At NYU Langone Medical Center (New York, NY), we believe the MRI should be performed prior to initial biopsy. Do it right the first time! If the patient has low risk for detecting significant prostate cancer based on risk calculators, one may forego prostate biopsy if multiparametric MRI shows no suspicious areas. This will significantly decrease risk of detecting incidental cancer.
The prostate health index or 4KScore® (OPKO Health, Miami, FL) assays have been shown to predict risk of detecting significant cancer for men with an elevated PSA level. The tests may be useful in avoiding both an MRI and prostate biopsy for men presenting with low risk of significant prostate cancer based on a risk calculator. In the present case, the progressively rising PSA value is indicative of aggressive prostate cancer likely in the target zone, so it is most appropriate to proceed directly to an MRI. In this case, an MRI would have likely identified the cancer on the first biopsy precluding the additional biopsies and delay in diagnosis.
Bjurlin MA, Meng X, Le Nobin J, et al. Optimization of prostate biopsy: the role of MRI targeted biopsy in detection, localization and risk assessment. J Urol. 2014;192:648-658.
Loeb S, Lilja H, Vickers A. Beyond prostate-specific antigen: utilizing novel strategies to screen men for prostate cancer. Curr Opin Urol. 2016;26:459-465.
Meng X, Rosenkrantz AB, Mendhiratta N, et al. Relationship between prebiopsy multiparametric magnetic resonance imaging (MRI), biopsy indication and MRI-ultrasound fusion-targeted prostate biopsy outcomes. Eur Urol. 2016;69:512-517.
