Andreas Hiester

Prospective Randomized Trial Comparing Magnetic Resonance Imaging (MRI)-guided In-bore Biopsy to MRI-ultrasound Fusion and Transrectal Ultrasound-guided Prostate Biopsy in Patients with Prior Negative Biopsies

BACKGROUND A significant proportion of prostate cancers (PCas) are missed by conventional transrectal ultrasound-guided biopsy (TRUS-GB). It remains unclear whether the combined approach using targeted magnetic resonance imaging (MRI)-ultrasound fusion-guided biopsy (FUS-GB) and systematic TRUS-GB is superior to targeted MRI-guided in-bore biopsy (IB-GB) for PCa detection. OBJECTIVE To compare PCa detection between IB-GB alone and FUS-GB + TRUS-GB in patients with at least one negative TRUS-GB and prostate-specific antigen ≥4 ng/ml. DESIGN, SETTING, AND PARTICIPANTS Patients were prospectively randomized after multiparametric prostate MRI to IB-GB (arm A) or FUS-GB + TRUS-GB (arm B) from November 2011 to July 2014. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS The study was powered at 80% to demonstrate an overall PCa detection rate of ≥60% in arm B compared to 40% in arm A. Secondary endpoints were the distribution of highest Gleason scores, the rate of detection of significant PCa (Gleason ≥7), the number of biopsy cores to detect one (significant) PCa, the positivity rate for biopsy cores, and tumor involvement per biopsy core. RESULTS AND LIMITATIONS The study was halted after interim analysis because the primary endpoint was not met. The trial enrolled 267 patients, of whom 210 were analyzed (106 randomized to arm A and 104 to arm B). PCa detection was 37% in arm A and 39% in arm B (95% confidence interval for difference, -16% to 11%; p=0.7). Detection rates for significant PCa (29% vs 32%; p=0.7) and the highest percentage tumor involvement per biopsy core (48% vs 42%; p=0.4) were similar between the arms. The mean number of cores was 5.6 versus 17 (p<0.001). A limitation is the limited number of patients because of early cessation of accrual. CONCLUSIONS This trial failed to identify an important improvement in detection rate for the combined biopsy approach over MRI-targeted biopsy alone. A prospective comparison between MRI-targeted biopsy alone and systematic TRUS-GB is justified. PATIENT SUMMARY Our randomized study showed similar prostate cancer detection rates between targeted prostate biopsy guided by magnetic resonance imaging and the combination of targeted biopsy and systematic transrectal ultrasound-guided prostate biopsy. An important improvement in detection rates using the combined biopsy approach can be excluded.

Feasibility of diffusional kurtosis tensor imaging in prostate MRI for the assessment of prostate cancer: preliminary results.

PURPOSE To assess the feasibility of full diffusional kurtosis tensor imaging (DKI) in prostate MRI in clinical routine. Histopathological correlation was achieved by targeted biopsy. MATERIALS AND METHODS Thirty-one men were prospectively included in the study. Twenty-one were referred to our hospital with increased prostate specific antigen (PSA) values (>4ng/ml) and suspicion of prostate cancer. The other 10 men were volunteers without any history of prostate disease. DKI applying diffusion gradients in 20 different spatial directions with four b-values (0, 300, 600, 1000s/mm(2)) was performed additionally to standard functional prostate MRI. Region of interest (ROI)-based measurements were performed in all histopathologically verified lesions of every patient, as well as in the peripheral zone, and the central gland of each volunteer. RESULTS DKI showed a substantially better fit to the diffusion-weighted signal than the monoexponential apparent diffusion coefficient (ADC). Altogether, 29 lesions were biopsied in 14 different patients with the following results: Gleason score 3+3=6 (n=1), 3+4=7 (n=7), 4+3=7 (n=6), 4+4=8 (n=1), and 4+5=9 (n=2), and prostatitis (n=12). Values of axial (Kax) and mean kurtosis (Kmean) were significantly different in the tumor (Kax 1.78±0.39, Kmean 1.84±0.43) compared with the normal peripheral zone (Kax 1.09±0.12, Kmean 1.16±0.13; p<0.001) or the central gland (Kax 1.40±0.12, Kmean 1.44±0.17; p=0.01 respectively). There was a minor correlation between axial kurtosis (r=0.19) and the Gleason score. CONCLUSION Full DKI is feasible to utilize in a routine clinical setting. Although there is some overlap some DKI parameters can significantly distinguish prostate cancer from the central gland or the normal peripheral zone. Nevertheless, the additional value of DKI compared with conventional monoexponential ADC calculation remains questionable and requires further research.

Risk Stratification of Equivocal Lesions on Multiparametric Magnetic Resonance Imaging of the Prostate

Purpose We systematically analyzed the records of patients with PI‐RADS™ (Prostate Imaging Reporting and Data System) 3 lesions, which are called equivocal according to PI‐RADS version 2, using prostate multiparametric magnetic resonance imaging and magnetic resonance imaging targeted biopsies. Systematic transrectal ultrasound guided biopsies served as the reference standard. Materials and Methods A total of 120 consecutive patients were retrospectively included in the study. In these patients the overall PI‐RADS score was 3 after 3 Tesla T2‐weighted imaging, diffusion weighted imaging and dynamic contrast enhanced multiparametric magnetic resonance imaging as well as subsequent targeted magnetic resonance imaging/ultrasound fusion guided biopsies plus systematic 12‐core transrectal ultrasound guided biopsies. The study end points were the prostate cancer detection rate, the Gleason score distribution, the prostate cancer location and risk stratification by subgroup analyses. Results Prostate cancer was detected in 13 of 118 patients for a detection rate of 11%, including 5 patients (4.2%) with a Gleason score of 3 + 4 = 7 or greater. Three of the 212 lesions (1.4%) in the transition zone and 6 of the 64 (9.4%) in the peripheral zone were positive for prostate cancer. Multiparametric magnetic resonance imaging revealed patterns of peripheral prostatitis combined with diffuse stromal hyperplasia in 54% of the patients with prostate cancer. Prostate volume was significantly lower in patients with prostate cancer (p = 0.015) but differences in prostate specific antigen levels were not statistically significant (p = 0.87). Prostate specific antigen density was higher in patients with prostate cancer (0.19 vs 0.12 ng/ml/ml). Conclusions Low grade prostate cancer (Gleason score 3 + 3 = 6) can develop in patients with an overall PI‐RADS score of 3. Prostate cancer with a Gleason score of 3 + 4 = 7 or greater can be detected by multiparametric magnetic resonance imaging with a high degree of certainty. Gleason score 4 + 3 = 7 or greater prostate cancer is unlikely in PI‐RADS 3 lesions. Therefore, these patients should primarily undergo followup multiparametric magnetic resonance imaging. In patients with a combination of multiparametric magnetic resonance imaging aspects of extensive prostatitis and diffuse stromal hyperplasia low prostate volume and/or high prostate specific antigen density biopsy might be considered.DISCLAIMER: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our subscribers we are providing this early version of the article. The paper will be copy edited and typeset, and proof will be reviewed before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to The Journal pertain.

Multiparametric Magnetic Resonance Imaging/Ultrasound Fusion Prostate Biopsy—Are 2 Biopsy Cores per Magnetic Resonance Imaging Lesion Required?

Purpose For multiparametric magnetic resonance imaging/ultrasound fusion prostate biopsy the number of biopsy cores obtained is arbitrarily established by urologists. Moreover, a general consensus is lacking on the number of biopsy cores to be obtained from a single magnetic resonance imaging lesion. Therefore, we evaluated the feasibility of obtaining only 1 biopsy core per magnetic resonance imaging lesion. Materials and Methods We retrospectively evaluated a total of 2,128 biopsy cores of 1,064 prostatic lesions (2 cores per lesion) in 418 patients in regard to prostate cancer detection (histology) and the Gleason score of the first biopsy core compared to the second biopsy core. Two analyses were performed, including patient level analysis based on prostate cancer detection per patient and lesion level analysis based exclusively on the histology of each lesion regardless of the overall histological outcome of the case. Results The overall prostate cancer detection rate was 45.7% (191 of 418 patients). The first biopsy core detected 170 of all 191 prostate cancers (89%). In 17 of these 170 prostate cancers (10%) the second biopsy core revealed Gleason score upgrading. Nine of the 21 prostate cancers (43%) missed by the first biopsy core had a Gleason score of 6. Altogether 537 of the 2,128 biopsy cores were positive, including 283 first (26.6%) and 254 second (24%) biopsy cores (p ≤0.001). The concordance between the first and second biopsy cores was 89% (&kgr; = 0.71). There was a discrepancy with Gleason score upgrading in 28 of 212 lesions (13.2%) with positive first and second biopsy cores. Conclusions Our study shows that obtaining more than 1 biopsy core per magnetic resonance imaging lesion only slightly improves the prostate cancer detection rate and Gleason grading.

PD23-05 MULTIPARAMETRIC-MRI/ULTRASOUND FUSION PROSTATE BIOPSY: ARE TWO BIOPSY CORES PER MRI-LESION REQUIRED?

Abstract Purpose For multiparametric MRI/Ultrasound fusion prostate biopsy (FUSBx) the number of taken biopsy cores is arbitrary established by urologists. Moreover, general consensus on the number of biopsy cores to be obtained from a single MRI-lesion is lacking. Therefore, we aimed to evaluate the feasibility of obtaining only one biopsy core per MRI-lesion. Materials and methods We retrospectively evaluated 2128 biopsy cores of 1064 prostatic lesions (two cores per lesion) in 418 patients regarding prostate cancer (PCa) detection (histology) and Gleason score (GS) of the first biopsy core (FBC) compared to the second biopsy core (SBC). Two different analyses were performed, patient-level analysis based on the PCa detection per patient and a second lesion-level analysis, which was based exclusively on the histology of every lesion, regardless the overall histological outcome of the patient. Results The overall PCa detection rate was 45.7% (191/418). The FBC detected 89% of all PCa (170/191). For 17 out of these 170 PCa the SBC revealed a GS upgrade (10%). Nine out of the 21 PCa missed by FBC had a GS 6 (43%). Altogether, 537 out of 2128 biopsy cores were positive, 283 (26.6%) were FBC and 254 (24%) SBC (p= Conclusion Our study shows that obtaining more than one biopsy core per MRI-lesion improves only slightly the PCa detection rate and the Gleason grading.