Reduction of false positives using zone-specific prostate-specific antigen density for prostate MRI-based biopsy decision strategies

OBJECTIVES

To develop and test zone-specific prostate-specific antigen density (sPSAD) combined with PI-RADS to guide prostate biopsy decision strategies (BDS).

METHODS

This retrospective study included consecutive patients, who underwent prostate MRI and biopsy (01/2012-10/2018). The whole gland and transition zone (TZ) were segmented at MRI using a retrained deep learning system (DLS; nnU-Net) to calculate PSAD and sPSAD, respectively. Additionally, sPSAD and PI-RADS were combined in a BDS, and diagnostic performances to detect Grade Group ≥ 2 (GG ≥ 2) prostate cancer were compared. Patient-based cancer detection using sPSAD was assessed by bootstrapping with 1000 repetitions and reported as area under the curve (AUC). Clinical utility of the BDS was tested in the hold-out test set using decision curve analysis. Statistics included nonparametric DeLong test for AUCs and Fisher-Yates test for remaining performance metrics.

RESULTS

A total of 1604 patients aged 67 (interquartile range, 61-73) with 48% GG ≥ 2 prevalence (774/1604) were evaluated. By employing DLS-based prostate and TZ volumes (DICE coefficients of 0.89 (95% confidence interval, 0.80-0.97) and 0.84 (0.70-0.99)), GG ≥ 2 detection using PSAD was inferior to sPSAD (AUC, 0.71 (0.68-0.74)/0.73 (0.70-0.76); p < 0.001). Combining PI-RADS with sPSAD, GG ≥ 2 detection specificity doubled from 18% (10-20%) to 43% (30-44%; p < 0.001) with similar sensitivity (93% (89-96%)/97% (94-99%); p = 0.052), when biopsies were taken in PI-RADS 4-5 and 3 only if sPSAD was ≥ 0.42 ng/mL/cc as compared to all PI-RADS 3-5 cases. Additionally, using the sPSAD-based BDS, false positives were reduced by 25% (123 (104-142)/165 (146-185); p < 0.001).

CONCLUSION

Using sPSAD to guide biopsy decisions in PI-RADS 3 lesions can reduce false positives at MRI while maintaining high sensitivity for GG ≥ 2 cancers.

CLINICAL RELEVANCE STATEMENT

Transition zone-specific prostate-specific antigen density can improve the accuracy of prostate cancer detection compared to MRI assessments alone, by lowering false-positive cases without significantly missing men with ISUP GG ≥ 2 cancers.

KEY POINTS

• Prostate biopsy decision strategies using PI-RADS at MRI are limited by a substantial proportion of false positives, not yielding grade group ≥ 2 prostate cancer. • PI-RADS combined with transition zone (TZ)-specific prostate-specific antigen density (PSAD) decreased the number of unproductive biopsies by 25% compared to PI-RADS only. • TZ-specific PSAD also improved the specificity of MRI-directed biopsies by 9% compared to the whole gland PSAD, while showing identical sensitivity.

Transplant nephrectomy: indication, surgical approach and complications-experiences from a single transplantation center

PURPOSE

Management of a failed kidney allograft, and the question whether it should be removed is a challenging task for clinicians. The reported risks for transplant nephrectomy (TN) vary, and there is no clear recommendation on indications or surgical approach that should be used. This study gives an overview of indications, compares surgical techniques, and identifies risk factors for higher morbidity.

METHODS

Retrospective analysis was conducted on all transplant nephrectomies performed between 2005 and 2020 at Charité Hospital Berlin, Department of Urology. Patient demographics, laboratory parameters, graft survival data, indication for TN, and surgical complications were extracted from medical reports.

RESULTS

A total of 195 TN were performed, with graft intolerance syndrome being the most common indication in 52 patients (26.7%), acute rejection in 36 (18.5%), acute infection in 30 (15.4%), and other reasons to stop immunosuppression in 26 patients (13.3%). Rare indications were vascular complications in 16 (8.2%) and malignancies in the allograft in six (3.1%) cases. Extracapsular surgical approach was significantly more often used in cases of vascular complications and earlier allograft removal, but there was no difference in complication rates between extra- and intracapsular approach. Acute infection was identified as an independent risk factor for a complication grade IIIb or higher according to Clavien-Dindo classification, with a HR of 12.3 (CI 2.2-67.7; p = 0.004).

CONCLUSION

Transplant nephrectomy should only be performed when there is a good indication, and non-elective surgery should be avoided, when possible, as it increases morbidity.

[Quality of life and outcome after holmium laser enucleation of the prostate (HoLEP)]

BACKGROUND

Holmium Laser Enucleation of the Prostate (HoLEP) was established 20 years ago as an alternative to Transurethral Resection of the Prostate (TUR-P) based on improved morbidity in patients with benign prostate syndrome (BPS). HoLEP can be applied independently to almost all sizes of prostate glands and is recommended in national and international guidelines. Although the HoLEP procedure has a good reputation, many patients still prefer conservative treatment due to fears of side-effects such as pain and urinary incontinence. The aim of this study was to identify patients' feelings, fears and perception of their HoLEP treatment based on Patient-reported Outcome Measures (PROMs) via questionnaires.

MATERIAL UND METHODS

During the time period from June to December 2020, 152 consecutive patients were treated by HoLEP due to BPS and were interviewed based on questionnaires right after their surgical treatment and 3 months later concerning their satisfaction as well as micturition and continence. Based on a written informed consent, 112 patients were included in the study, and a complete 3-month follow-up was available for 88 patients.

RESULTS

The mean volume of enucleated prostate tissue was 62.1 [g] and the mean prostate volume estimated pre-operatively (trans-rectal ultrasound) was 83.1 [cm3]. Overall patient-reported satisfaction with the hospital stay including surgical treatment was 94.6%; after 3 months it was 91.8%. Concerning micturition, 76.5% of the patients reported satisfaction after surgery and 80.4% were satisfied after 3 months. Urinary incontinence was reported in 8.3% initially and in 9.1% after 3 months. Positive answers to questions concerning the quality of life index [L] were obtained in 62.1% initially and their number increased to 85.7% after 3 months. The share of negative answers decreased from 11.7% after surgery to 3.4% within the 3-month follow-up.

DISCUSSION

HoLEP is a well-established treatment of BPS with lower side-effects compared with TUR-P according to the literature. To address doubts and misgivings, it is important to perform surveys on subjective patient satisfaction after the surgical procedure and over time. The high patient satisfaction could help future patients and the urologists treating them to establish the indication for HoLEP treatment earlier in order to avoid severe LUTS or catheterization.

Follow-up of men with a PI-RADS 4/5 lesion after negative MRI/Ultrasound fusion biopsy

Magnetic resonance imaging/Ultrasound (MRI/US) fusion targeted biopsy (TB) in combination with a systematic biopsy (SB) improves cancer detection but limited data is available how to manage patients with a Prostate Imaging-Reporting and Data System (PI-RADS) ≥ 4 lesion and a negative biopsy. We evaluate the real-world management and the rate of clinically significant Prostate Cancer (csPCa) during follow-up. 1546 patients with a multi-parametric MRI (mpMRI) and a PI-RADS ≥ 3 who underwent SB and TB between January 2012 and May 2017 were retrospectively analyzed. 222 men with a PI-RADS ≥ 4 and a negative biopsy were included until 2019. For 177/222 (80%) complete follow-up data was obtained. 66/84 (78%) had an initial PI-RADS 4 and 18 (22%) a PI-RADS 5 lesion. 48% (84/177) received a repeat mpMRI; in the follow-up mpMRI, 39/84 (46%) lesions were downgraded to PI-RADS 2 and 11 (13%) to PI-RADS 3; three cases were upgraded and 28 lesions remained consistent. 18% (32/177) men underwent repeated TB and csPCa was detected in 44% (14/32). Our study presents real world data on the management of men with a negative TB biopsy. Men with a positive mpMRI and lesions with high suspicion (PI-RADS4/5) and a negative targeted biopsy should be critically reviewed and considered for repeat biopsy or strict surveillance. The optimal clinical risk assessment remains to be further evaluated.

Prediction of prostate cancer grade using fractal analysis of perfusion MRI: retrospective proof-of-principle study

OBJECTIVES

Multiparametric MRI has high diagnostic accuracy for detecting prostate cancer, but non-invasive prediction of tumor grade remains challenging. Characterizing tumor perfusion by exploiting the fractal nature of vascular anatomy might elucidate the aggressive potential of a tumor. This study introduces the concept of fractal analysis for characterizing prostate cancer perfusion and reports about its usefulness for non-invasive prediction of tumor grade.

METHODS

We retrospectively analyzed the openly available PROSTATEx dataset with 112 cancer foci in 99 patients. In all patients, histological grading groups specified by the International Society of Urological Pathology (ISUP) were obtained from in-bore MRI-guided biopsy. Fractal analysis of dynamic contrast-enhanced perfusion MRI sequences was performed, yielding fractal dimension (FD) as quantitative descriptor. Two-class and multiclass diagnostic accuracy was analyzed using area under the curve (AUC) receiver operating characteristic analysis, and optimal FD cutoffs were established. Additionally, we compared fractal analysis to conventional apparent diffusion coefficient (ADC) measurements.

RESULTS

Fractal analysis of perfusion allowed accurate differentiation of non-significant (group 1) and clinically significant (groups 2-5) cancer with a sensitivity of 91% (confidence interval [CI]: 83-96%) and a specificity of 86% (CI: 73-94%). FD correlated linearly with ISUP groups (r² = 0.874, p < 0.001). Significant groupwise differences were obtained between low, intermediate, and high ISUP group 1-4 (p ≤ 0.001) but not group 5 tumors. Fractal analysis of perfusion was significantly more reliable than ADC in predicting non-significant and clinically significant cancer (AUC_FD = 0.97 versus AUC_ADC = 0.77, p < 0.001).

CONCLUSION

Fractal analysis of perfusion MRI accurately predicts prostate cancer grading in low-, intermediate-, and high-, but not highest-grade, tumors.

KEY POINTS

• In 112 prostate carcinomas, fractal analysis of MR perfusion imaging accurately differentiated low-, intermediate-, and high-grade cancer (ISUP grade groups 1-4). • Fractal analysis detected clinically significant prostate cancer with a sensitivity of 91% (83-96%) and a specificity of 86% (73-94%). • Fractal dimension of perfusion at the tumor margin may provide an imaging biomarker to predict prostate cancer grading.

Comparison of PHI and PHI Density for Prostate Cancer Detection in a Large Retrospective Caucasian Cohort

BACKGROUND

Beyond prostate-specific antigen (PSA), other biomarkers for prostate cancer (PCa) detection are available and need to be evaluated for clinical routine.

OBJECTIVE

The aim of the study was to evaluate the Prostate Health Index (PHI) density (PHID) in comparison with PHI in a large Caucasian group >1,000 men.

METHODS

PHID values were used from available patient data with PSA, free PSA, and [-2]pro-PSA and prostate volume from 3 former surveys from 2002 to 2014. Those 1,446 patients from a single-center cohort included 701 men with PCa and 745 with no PCa. All patients received initial or repeat biopsies. The diagnostic accuracy was evaluated by receiver operating characteristic (ROC) curves comparing area under the ROC curves (AUCs), precision-recall approach, and decision curve analysis (DCA).

RESULTS

PHID medians differed almost 2-fold between PCa (1.12) and no PCa (0.62) in comparison to PHI (48.6 vs. 33; p always <0.0001). However, PHID and PHI were equal regarding the AUC (0.737 vs. 0.749; p = 0.226), and the curves of the precision-recall analysis also overlapped in the sensitivity range between 70 and 100%. DCA had a maximum net benefit of only ∼5% for PHID versus PHI between 45 and 55% threshold probability. Contrary, in the 689 men with a prostate volume ≤40 cm3, PHI (AUC 0.732) showed a significant larger AUC than PHID (AUC 0.69, p = 0.014).

CONCLUSIONS

Based on DCA, PHID had only a small advantage in comparison with PHI alone, while ROC analysis and precision-recall analysis showed similar results. In smaller prostates, PHI even outperformed PHID. The increment for PHID in this large Caucasian cohort is too small to justify a routine clinical use.

Use of TDI during MRI/US fusion-guided biopsy for suspected prostate cancer

BACKGROUND

Tissue Doppler imaging (TDI) uses the Doppler principle to quantify the movement of biological tissues.

OBJECTIVE

To investigate the contribution of TDI parameters derived during magnetic resonance imaging and ultrasound (MRI/US) fusion-guided biopsy for prostate cancer (PCa) discrimination.

METHODS

From March 2016 to Dec. 2018, 75 men with suspected PCa prospectively underwent fusion-guided prostate biopsy. TDI overlaid on predefined target lesion were compared to the confirmed contralateral tumor-free area of the prostate gland (using Image J). Diagnostic value of TDI parameters was assessed using histopathology as standard of reference.

RESULTS

Thirty-seven patients were diagnosed with PCa (49.3%), among them 27 with clinically significant PCa (Gleason score >  3 + 3 = 6 (ISUP 1). The LES/REF ratio was lower in confirmed PCa patients compared to patients without PCa (0.42, IQR, 0.22-0.59 vs. 0.52, IQR, 0.40-0.72, p = 0.017). TDI parameters allowed differentiation of low-risk from high-to-intermediate-risk PCa (ISUP 2 versus ISUP 3) based on lower pixel counts within the target ROI (1340, IQR 596-2430 vs. 2687, IQR 2453-3216, p = 0.004), lower pixel percentage (16.4 IQR 11.4-29.5 vs. 27.3, IQR 22.1-39.5; p = 0.005), and lower LES/REF ratios (0.29, IQR 0.19-0.51 vs. 0.52, IQR 0.47-0.74, p = 0.001).

CONCLUSION

TDI of prostate lesions prelocated by MRI discriminates between cancerous and noncancerous lesions and further seems to enable characterization of PCa aggressiveness. This widely available US technique may improve confidence in target lesion localization for tissue sampling.

Focal Segmental Glomerulosclerosis and Recurrence in Living Donor Recipients

Purpose

Focal segmental glomerulosclerosis (FSGS) is a common cause for end-stage renal disease that can recur in the graft after kidney transplantation. The incidence of FSGS recurrence is reported in up to 47% of patients, predisposing those to possible poorer transplantation outcomes. Hence, we examined the incidence of FSGS recurrence and the effect on graft outcome in our patient cohort of living donor kidney transplantations (LDKT).

Patients and Methods

We analyzed 194 adult patients who received a LDKT between 2011 and 2017 of which 22 (11%) had FSGS as underlying disease. Demographic data and clinical outcomes, especially regarding recurrence of FSGS, were evaluated.

Results

FSGS recurrence was identified in three (14%) patients within three months after transplantation, of whom two patients (9%) lost their graft. There was no significant difference in graft survival comparing FSGS to other reasons for end-stage renal disease.

Conclusion

Incidence of FSGS recurrence in the present patient cohort was within the range reported in the literature and comparatively low. Our data support LDKT as a treatment option in patients with end-stage renal disease due to FSGS.

Contrast-enhanced ultrasound (CEUS) reliably rules out neoplasm in developmental renal pseudotumor

BACKGROUND

Renal pseudotumors appear as benign cortical hypertrophies and are typically assessed by contrast-enhanced computed tomography or magnetic resonance imaging to rule out malignancy.

PURPOSE

To investigate whether contrast-enhanced ultrasound (CEUS) can rule out renal neoplasm and thus potentially reduce cross-sectional imaging and further follow-up in these patients.

MATERIAL AND METHODS

Thirty-two patients with presumption of developmental renal pseudotumor on CEUS between June 2011 and July 2019 were retrospectively analyzed. All patients were examined with a standardized renal US protocol including B-mode, color-coded duplex sonography (CCDS), and CEUS by an experienced radiologist (EFSUMB level 3). Images were retrospectively interpreted in consensus by two highly experienced radiologists. Histopathological reports, cross-sectional imaging findings, and clinical course (treatment response, long-term imaging follow-up) were defined as standard of reference.

RESULTS

CEUS correctly identified 8/9 neoplastic lesions and missed one oncocytoma within the 32 included patients. Irregular vessel structure (88.9% vs. 13.0%, P = 0.007) and hyperenhancement (66.6% vs. 17.4%, P = 0.031) on CEUS were more common in neoplasm compared to developmental pseudotumors reaching statistical significance. Compared with the standard of reference, CEUS had 89% sensitivity (95% confidence interval [CI] 57-98), 96% specificity (95% CI 80-99), a positive predictive value of 89% (95% CI 57-98), and a negative predictive value of 96% (95% CI 79-99) for ruling out renal malignancy in developmental pseudotumors.

CONCLUSION

CEUS is a safe and fast method to rule out neoplasm in the diagnostic work-up of renal pseudotumors. In conjunction with B-mode and CCDS, CEUS has the potential to reduce further (invasive) diagnostic procedures.

The discriminative ability of Prostate Health Index to detect prostate cancer is enhanced in combination with miR-222-3p

BACKGROUND

There is an urgent need for better prostate cancer (PCa) biomarkers due to the low specificity of prostate specific antigen (PSA).

OBJECTIVE

Prostate Health Index (PHI) is an advanced PSA-based test for early detection of PCa. The present study aim was to investigate the potential improvement of diagnostic accuracy of PHI by its combination with suitable discriminative microRNAs (miRNAs).

METHODS

A two-phase study was performed. In a discovery phase, a panel of 177 miRNAs was measured in ten men with biopsy proven PCa and ten men with histologically no evidence of malignancy (NEM). These results were validated in a second phase including 25 patients in each group. The patients of all groups were matched regarding their PSA values and PHI were measured.

RESULTS

Based on data in the discovery phase, four elevated miRNAs were selected as potential miRNA candidates for further validation. A combination of miR-222-3p as the best discriminative miRNA with PHI extended the diagnostic accuracy of PHI from an AUC value of 0.690 to 0.787 and resulted in a sensitivity of 72.0% and a specificity of 84.0%.

CONCLUSION

Circulating microRNAs show useful diagnostic potential in combination with common used biomarkers to enhance their diagnostic power.

Early Continence and Extravasation After Open Retropubic Radical Prostatectomy - Interrupted vs Continuous Suturing for Vesicourethral Anastomosis

Purpose

To compare running suture (RS) and interrupted suture (IS) of vesicourethral anastomosis (VUA) during open retropubic radical prostatectomy (RRP) on early urinary continence and extravasation.

Patients and Methods

Single center analysis of 211 patients who underwent RRP performed by a single surgeon during 2008 to 2017 was retrospectively analyzed. For VUA, we used the standard interrupted suture technique (n=100) with a 3-0 PDS suture. The RS (n=111) was performed with 12-bite suture using 3-0 PDS. The primary endpoints were extravasation and early continence. Demographic and peri-operative data were collected and analyzed using Pearson's chi-square, t-Test and Mann-Whitney U-test. A binary logistic regression analysis was carried out to explore predictors that affected early continence after catheter removal.

Results

The rates of early urinary incontinence (UI) were 7.7% vs 42.2% (p<0.001). The duration of catheterization and hospitalization was significantly shorter in the interrupted group (4 days vs 5 days, p<0.001 and 5 days vs 6 days, p<0.001). The groups did not differ significantly in body mass index or prostate volume. There were older patients and higher PSA levels in the group with RS technique. No significant difference was found in the postoperative extravasation rates between both groups (13.5% vs 12%, p=0.742).

Conclusion

Running vesicourethral anastomosis increased the rate of early urinary incontinence. Both anastomosis techniques provided a similar rate of postoperative urine extravasation. VUA should only be one of the many criteria that must be considered for the preservation of urinary continence of patients after RRP.

Nephron Sparing Surgery in Renal Allograft in Recipients with de novo Renal Cell Carcinoma: Two Case Reports and Review of the Literature

We report 2 cases of de novo renal cell carcinoma (RCC) in renal grafts after transplantation. Both patients underwent nephron sparing surgery (NSS) 211 and 167 months after transplantation, revealing papillary RCC with a tumour size >4 cm (pT1a). Within a follow-up of 25 and 32 months after NSS, a stable renal function without indication for dialysis was present. No recurrence of RCC in both cases was reported within the yearly routine examinations. NSS in kidney allografts is a safe procedure with preservation of renal function.

Semi-automatic prostatic artery detection using cone-beam CT during prostatic arterial embolization

BACKGROUND

Due to the broad variability of the prostatic artery (PA), its origin, small calibers, and tortuous courses, prostatic arterial embolization (PAE) is challenging, time-consuming, and results in high radiation doses.

PURPOSE

To evaluate the accuracy of PA detection using cone-beam computed tomography (CBCT) performed from the aortic bifurcation in combination with a semi-automatic detection software in comparison to oblique view digital subtraction angiography (DSA) with internal iliac artery (IIA) injection.

MATERIAL AND METHODS

Twenty-two consecutive patients were included in this retrospective, IRB-approved study between July and December 2017. CBCT from the aorta and 30° oblique-view DSA from both IIAs were obtained for PA detection. Results of suggested PAs from the semi-automatic vessel detection software after CBCT and IIA DSA were compared. Moreover, dose area product (DAP) was recorded. Statistical analysis included Spearman's correlation, Mann-Whitney U test, and the Wilcoxon test considering P<0.05 as significant.

RESULTS

PA type was classified significantly better with CBCT compared to DSA (P=0.047). In IIA DSA, PAs could not be identified in 18% on the left and in 17% on the right side. CBCT detected all PAs, although truncation occurred in 59% because of the limited field of view. Mean DAP of the whole procedure was 257,161.32±127,909.36 mGy*cm². Mean DAPs were for a single DSA 14,502.51±9,437.67 mGy*cm² and for one CBCT 15,589.23±2,722.49 mGy*cm². A mean of 14.82 DSAs and only one CBCT were performed. CBCT accounted for 6% and DSA for 84% of the entire DAP of the procedure.

CONCLUSION

CBCT with semi-automatic feeding vessel detection software detects PAs more accurately than IIA DSA and may reduce radiation dose.

[A retrospective analysis of functional and oncologic outcomes following surgical treatment of patients with pT1/pT2 renal cell carcinoma at a tertiary referral centre]

INTRODUCTION

In patients with localised renal cell carcinoma, the only curative treatment option is surgical tumour excision. The aim of this study was to evaluate peri- and postoperative outcomes as well as oncologic and functional long-term results following surgical treatment of patients with renal cell carcinoma (pT1/pT2) at a tertiary referral centre.

PATIENTS AND METHODS

This retrospective study included a total of 758 patients with localised renal cell carcinoma (pT1 /pT2), who underwent radical (RN) or partial (PN) nephrectomy between 01/2008 and 10/2014. Pre-, peri- and postoperative parameters were recorded. Oncologic and functional long-term data were retrieved through questionnaires and structured telephone interviews.

RESULTS

Laparoscopic RN or PN resulted in less blood loss and lower peri- and postoperative complication rates compared to open procedures. Regarding short- and long-term renal function, a higher increase in serum creatinine levels was detected after RN. No difference was noted in health status and quality of life. Median follow-up was 36 months. A total of 10.4 % of patients died during follow-up. 4.7 % and 8.4 % developed a relapse or metastatic disease. No difference was found between laparoscopic and open RN/PNs in terms of oncologic long-term results.

DISCUSSION

In conclusion, all surgical techniques evaluated in this study provided good oncologic and functional short-/long-term outcomes.

Is a Retroaortic Vein a Risk Factor in Laparoscopic Living Donor Nephrectomy?

INTRODUCTION

In living donor transplantation choosing the right donor and donor side for laparoscopic donor nephrectomy is a challenging task in clinical practice. Knowledge about anomalies in renal blood supply are crucial to evaluate the feasibility of the operative procedure. Few data so far exist whether the existence of a retroaortic left renal vein has an impact on living kidney transplantation outcome for donor and recipient.

MATERIALS AND METHODS

We retrospectively analyzed 221 patients who underwent laparoscopic living donor nephrectomy between 2011 and 2017 for existence of a retroaortic left renal vein. Clinical characteristics and operative outcomes for donors and recipients were analyzed.

RESULTS

221 patients underwent donor nephrectomy between 2011 and 2017; 11 patients (4.98%) showed the feature of a retroaortic left renal vein, and in 8 patients (72.7%) out of those 11 the left kidney was chosen for transplantation. Mean preoperative serum creatinine was 0.77 (0.49-0.98) mg/dL and 1.28 (0.97-1.64) mg/dL at discharge. In recipients mean serum creatinine preoperatively, after 1 week, 1 month,1 year, 2 and 3 years of follow-up was 10.36 (6.09-20.77) mg/dL, 1.71 (0.67-2.72), 1.33 (0.70-1.89), 1.31 (0.95-2.13), 1.31 (0.98-2.13) and 1.33 (1.03-1.84), respectively. Neither donors nor recipients suffered from any operative complications.

CONCLUSIONS

Laparoscopic living donor nephrectomy of a left kidney with retroaortic renal vein is safe for the donor, without limitation in the outcome for the recipient.

Additive Value of Transrectal Systematic Ventral Biopsies in Combination with Magnet Resonance Imaging/Ultrasound Fusion-Guided Biopsy in Patients with 3 or More Negative Prostate Biopsies

INTRODUCTION

Patients with consistent suspicion for prostate cancer (PCa) and multiple negative prebiopsies prior to multiparametric magnetic resonance imaging (mpMRI) are still frequently evaluated for an image-guided biopsy and are reported with heterogeneous detection rates. The inclusion of a systematic biopsy (SB) is also still recommended with predominant sampling within the posterior/peripheral zone of the prostate. The aim of this study was (I) to evaluate PCa detection rates using a modified 10 core SB template including anterior biopsies in combination with mpMRI/ultrasound fusion-guided targeted biopsy (TB) in patients with 3 or more negative prebiopsies and (II) to compare mpMRI index lesion localization with histologically confirmed locali-zation from associated prostatectomy samples.

METHODS

Overall 1,337 consecutive patients underwent sensor-based registration TB of the prostate and a subsequent 10-core SB between January 2012 and December 2015 at our institution. For this study, 101 patients with ≥3 negative prebiopsies and prostate imaging - reporting data system lesions ≥3 were pooled prospectively and underwent TB and a modified SB including 2 ventral (anterior) biopsies. Detection rates were estimated for the modified SB, TB, and its combination. A subgroup analysis of 35 patients undergoing prostatectomy was performed by a head-to-head comparison of mpMRI index lesion and histologically confirmed PCa index lesion localization.

RESULTS

The overall detection rate for PCa was 54.5%. The combination of TB and SB detected 14 (25.4%) more cases missed by TB alone (p < 0.001) and 7 (12.7%) more cases missed by SB alone (p = 0.016), respectively. A postoperative Gleason upgrade was seen in 12/35 (34.3%) cases within the TB group and in 14/35 (40.0%) in the SB group, respectively. The subgroup analysis showed a predominant location of PCa index lesions anteriorly at the level of the midgland. The MRI detection rate of the anteriorly located index lesions was 70.4% (15/21 cases) with a clinically significant Gleason score (≥3 + 4 = 7a [International Society of Urological Pathology grade 2]) in 80.9%. Interestingly a modified SB template detected 90.5% (19/21) of the anteriorly located index lesions.

CONCLUSION

Our data suggest that in patients with multiple prebiopsies PCa seems to be predominantly located anteriorly. We suggest the general integration of anterior biopsies despite TB in repeat biopsy patients.

Lymphatic micrometastases predict biochemical recurrence in patients undergoing radical prostatectomy and pelvic lymph node dissection for prostate cancer

BACKGROUND

 Nodal metastasis is a strong prognostic parameter in prostate cancer (PCa). We analysed the detection of micrometastases (miN + ) in initially nodal-negative (pN0) radical prostatectomy specimens from pT2a-c and pT3a PCa patients by immunohistochemistry (IHC).

MATERIAL AND METHODS

 A total of 2352 lymph nodes of 193 PCa patients were centrally re-examined for miN + or miN- status using IHC. Results were correlated with clinical and follow-up data. Recurrence-free survival (RFS) was calculated with the log-rank test using the Kaplan-Meier method. In addition, a logistic regression analysis was performed.

RESULTS

 IHC detected miN + in a total of 17 patients (8.8 %). miN + seemed to be significantly associated with a higher Gleason score and was detected in more advanced pT stages. A total of 45 patients (23.1 %) had a biochemical recurrence (BCR). BCR was associated with miN +. Patients with miN + had a significantly shorter RFS (22.9 versus 58.7 months; p < 0.001). In the univariate (OR: 5.04; 95 % CI: 2.46 - 10.6; p-value: < 0.0001) and multivariate (OR: 3.29; 95 % CI: 1.54 - 7.08; p-value: 0.002) regression model, the miN + status was the strongest predictor of a BCR.

CONCLUSIONS

 IHC seems to be of high diagnostic value for the detection of micrometastases in initially nodal-negative PCa patients. IHC should therefore be performed in PCa patients with nodal-negative findings.

Native Nephrectomy before and after Renal Transplantation in Patients with Autosomal Dominant Polycystic Kidney Disease (ADPKD)

The aim of this study was 1) to evaluate and compare pre-, peri-, and post-operative data of Autosomal Dominant Polycystic Kidney Disease (ADPKD) patients undergoing native nephrectomy (NN) either before or after renal transplantation and 2) to identify advantages of optimal surgical timing, postoperative outcomes, and economical aspects in a tertiary transplant centre. This retrospective analysis included 121 patients divided into two groups-group 1: patients who underwent NN prior to receiving a kidney transplant (n = 89) and group 2: patients who underwent NN post-transplant (n = 32). Data analysis was performed according to demographic patient details, surgical indication, laboratory parameters, perioperative complications, underlying pathology, and associated mortality. There was no significant difference in patient demographics between the groups, however right-sided nephrectomy was performed predominantly within group 1. The main indication in both groups undergoing a nephrectomy was pain. Patients among group 2 had no postoperative kidney failure and a significantly shorter hospital stay. Higher rates of more severe complications were observed in group 1, even though this was not statistically significant. Even though the differences between both groups were substantial, the time of NN prior or post-transplant does not seem to affect short-term and long-term transplantation outcomes. Retroperitoneal NN remains a low risk treatment option in patients with symptomatic ADPKD and can be performed either pre- or post-kidney transplantation depending on patients' symptom severity.

Perioperative and oncologic outcome in patients treated for renal cell carcinoma with an extended inferior vena cava tumour thrombus level II-IV

PURPOSE

 Surgical treatment of patients with renal cell carcinoma (RCC) and an extended tumour thrombus (TT) in the inferior vena cava (IVC) is challenging and often requires a multidisciplinary approach. The aim of this study was to analyse results in the real-world management of RCC patients with an extended IVC TT (level II-IV according to the Mayo classification of macroscopic venous invasion in RCC) in terms of pre-, peri- and postoperative outcome, complications and oncologic outcome.

METHODS

 We investigated 61 patients with evidence of RCC and an extended TT in the IVC undergoing radical nephrectomy and tumour thrombectomy at our tertiary referral centre. Patients and operative characteristics were recorded and complications were analysed using the Clavien-Dindo classification. Follow-up data were retrieved by contacting the treating outpatient urologists, general practitioners and patients.

RESULTS

 The TT level was II in 36, III in 8 and IV in 17 patients. Complications grade IIIb and higher according to the Clavien-Dindo classification occurred in n = 3 (8.4 %), n = 2 (25.0 %) and n = 5 (29.5 %) patients with level II, III and IV TT, respectively. The overall survival of patients with TT level II, III and IV at 24 months (60 months) was 66.9 % (41.6 %), 83.3 % (83.3 %) and 64.1 % (51.3 %). Presence of primary metastatic disease was the only significant independent predictor for OS.  CONCLUSIONS:  Radical nephrectomy with tumour thrombectomy appears to be a feasible and effective treatment option in the management of patients with RCC and an extended IVC TT.

Contrast-Enhanced Ultrasound (CEUS) and Quantitative Perfusion Analysis in Patients with Suspicion for Prostate Cancer

PURPOSE

 The aim of this study was to investigate contrast-enhanced ultrasound (CEUS) parameters acquired by software during magnetic resonance imaging (MRI) US fusion-guided biopsy for prostate cancer (PCa) detection and discrimination.

MATERIALS AND METHODS

 From 2012 to 2015, 158 out of 165 men with suspicion for PCa and with at least 1 negative biopsy of the prostate were included and underwent a multi-parametric 3 Tesla MRI and an MRI/US fusion-guided biopsy, consecutively. CEUS was conducted during biopsy with intravenous bolus application of 2.4 mL of SonoVue^® (Bracco, Milan, Italy). In the latter CEUS clips were investigated using quantitative perfusion analysis software (VueBox, Bracco). The area of strongest enhancement within the MRI pre-located region was investigated and all available parameters from the quantification tool box were collected and analyzed for PCa and its further differentiation was based on the histopathological results.

RESULTS

 The overall detection rate was 74 (47 %) PCa cases in 158 included patients. From these 74 PCa cases, 49 (66 %) were graded Gleason ≥ 3 + 4 = 7 (ISUP ≥ 2) PCa. The best results for cancer detection over all quantitative perfusion parameters were rise time (p = 0.026) and time to peak (p = 0.037). Within the subgroup analysis (> vs ≤ 3 + 4 = 7a (ISUP 2)), peak enhancement (p = 0.012), wash-in rate (p = 0.011), wash-out rate (p = 0.007) and wash-in perfusion index (p = 0.014) also showed statistical significance.

CONCLUSION

 The quantification of CEUS parameters was able to discriminate PCa aggressiveness during MRI/US fusion-guided prostate biopsy.

[The use of partial nephrectomy in the treatment of patients with pT1/pT2 renal cell carcinoma: a trend analysis from a tertiary referral centre]

INTRODUCTION

 In patients with localised renal cell carcinoma, the only curative treatment option is surgical tumour excision. Current national and European guidelines recommend partial nephrectomy in the form of an open or minimally-invasive procedure in case of small tumours. The aim of this study was to examine the use of radical (RN) or partial (PN) nephrectomy performed as open or minimally-invasive procedures in patients with pT1 /pT2 renal cell carcinoma at a tertiary referral centre.

PATIENTS AND METHODS

 This retrospective study included a total of 758 patients with localised renal cell carcinoma (pT1/pT2), who underwent PN or RN between 01/2008 and 10/2014. Nephrectomy was either performed as an open (OPN, ORN), laparoscopic (LPN, LRN) or robot-assisted laparoscopic (RAPN) procedure.

RESULTS

 Out of 758 patients, 439 (57.9 %) underwent PN performed as an LPN in n = 254 (57.9 %) and OPN in n = 185 (42.1 %). 319 patients (42.1 %) underwent RN performed as an LRN in n = 250 (78.4 %) and ORN in n = 69 (21.6 %). Between 2008 and 2014, there was a trend towards the use of PN, especially in patients with pT1a and pT1b. The majority of patients with pT2 underwent RN, performed as an LRN in 40 - 53.9 %.

DISCUSSION

 The results of this trend analysis from a tertiary referral centre demonstrate an increased use of PN and minimally-invasive procedures over time, as recommend by national and European guidelines.

Validation of Prostate Imaging Reporting and Data System Version 2 for the Detection of Prostate Cancer

PURPOSE

The second version of the PI-RADS™ (Prostate Imaging Reporting and Data System) was introduced in 2015 to standardize the interpretation and reporting of prostate multiparametric magnetic resonance imaging. Recently low cancer detection rates were reported for PI-RADS version 2 category 4 lesions. Therefore the aim of the study was to evaluate the cancer detection rate of PI-RADS version 2 in a large prospective cohort.

MATERIALS AND METHODS

The study included 704 consecutive men with primary or prior negative biopsies who underwent magnetic resonance imaging/ultrasound fusion guided targeted biopsy and 10-core systematic prostate biopsy between September 2015 and May 2017. All lesions were rated according to PI-RADS version 2 and lesions with PI-RADS version 2 category 3 or greater were biopsied. An ISUP (International Society of Urological Pathology) score of 2 or greater (ie Gleason 3 + 4 or greater) was defined as clinically significant prostate cancer.

RESULTS

The overall cancer detection rate of PI-RADS version 2 categories 3, 4 and 5 was 39%, 72% and 91% for all prostate cancer, and 23%, 49% and 77% for all clinically significant prostate cancer, respectively. If only targeted biopsy had been performed, 59 clinically significant tumors (16%) would have been missed. The PI-RADS version 2 score was significantly associated with the presence of prostate cancer (p <0.001), the presence of clinically significant prostate cancer (p <0.001) and the ISUP grade (p <0.001).

CONCLUSIONS

PI-RADS version 2 is significantly associated with the presence of clinically significant prostate cancer. The cancer detection rate of PI-RADS version 2 category 4 lesions was considerably higher than previously reported. When performing targeted biopsy, the combination with systematic biopsy still provides the highest detection of clinically significant prostate cancer.

Primary magnetic resonance imaging/ultrasonography fusion-guided biopsy of the prostate

OBJECTIVE

To examine the performance of a primary magnetic resonance imaging (MRI)/ultrasonography (US) fusion-guided targeted biopsy (TB), and in combination with an added systematic biopsy (SB).

PATIENTS AND METHODS

Analysis of 318 consecutive biopsy-naïve men with suspicious multiparametric MRI (mpMRI; Prostate Imaging Reporting and Data System [PI-RADS] score ≥3) undergoing transrectal TB and 10-core SB between January 2012 and December 2016. The indication for performing mpMRI was based on clinical parameters and decided by the treating urologist before admission. TB was performed with a sensor-based MRI/US fusion-guided platform. Clinically significant prostate cancer was defined as Gleason score ≥4 + 3 = 7 (International Society of Urological Pathology Grade [ISUP] grade 3) or maximum cancer core length of ≥6 mm.

RESULTS

A median (interquartile range) of 14 (13-14) biopsies per case were taken. The overall cancer detection rate (CDR) was 77% (245/318). The TB alone detected 67% of prostate cancers and the SB alone detected 70%. The PI-RADS dependent CDR for the combination of TB/SB were 38% (21/55), 78% (120/154) and 95% (104/109) for PI-RADS scores of 3/4/5, respectively. Clinically significant prostate cancer was diagnosed by the combination of TB and SB in 195 men (61%) and by TB alone in 163 cases (51%). The number of missed or underestimated prostate cancers with a Gleason score ≥8 for TB alone was 31 (10%, P < 0.001) and 21 (7%, P < 0.001) for SB alone in comparison with the results of the combination of TB and SB. The rate of insignificant prostate cancer was comparable for the combination of TB and SB and TB alone (50/318, 16% vs 50/318, 16%).

CONCLUSIONS

Pre-biopsy mpMRI is of incremental value in increasing the detection of clinically significant prostate cancer in biopsy-naïve patients with suspicion of prostate cancer. Combining TB with SB further improved the diagnostic accuracy without increasing the rate of insignificant prostate cancer.

MRI-TRUS fusion for electrode positioning during irreversible electroporation for treatment of prostate cancer

We aimed to introduce an approach for image-guided positioning of electrodes for irreversible electroporation (IRE) in patients with prostate cancer using a magnetic resonance imaging-transrectal ultrasonography (MRI-TRUS) fusion technique. In 10 consecutive patients with biopsy-proven Gleason score ≤3+4 prostate cancer, 19 G electrodes were inserted into the prostate using a transperineal access. Magnetic resonance images of the prostate acquired before IRE were fused with transrectal ultrasound images acquired during IRE. The position of the ultrasound probe was tracked via a sensor and corresponding magnetic resonance images were calculated in real-time. While MRI allowed delineation of the target volume, the position of the electrodes could be visualized on ultrasound images; the distance between individual electrode pairs was measured. Based on these measurements the software installed on the IRE unit was able to calculate the voltage necessary to generate the electric field for ablation. Using contrast-enhanced ultrasound, changes in perfusion within the ablation zone after IRE were documented. This technique allowed positioning of the electrodes around the target volume under image guidance in all patients treated with IRE. The target lesion and a safety margin were covered within the estimated ablation zone. MRI-TRUS guidance for IRE combines the advantages of good visualization of the target lesion on MRI with the ability of ultrasound to acquire imaging in real-time with a mobile device.

[Implications of PI-RADS Version 1 and Updated Version 2 on the Scoring of Prostatic Lesions in Multiparametric MRI]

BACKGROUND

A revised version of the PI-RADS scoring system has been introduced and score-related variability between version 1 and 2 may be suspected. This study aimed to assess the PI-RADS scores derived from version 1 (v1) and the updated version 2 (v2).

MATERIAL AND METHODS

61 patients with biopsy-proven prostate cancer (PCa) and 90 lesions detected on pre-biopsy 3-Tesla multiparametric MRI were included in this retrospective analysis. 2 experienced radiologists scored all lesions in consensus. Lesion scores differing between PI-RADS v1 and v2 were further analyzed. Histology data from radical prostatectomy (RP) were included when available.

RESULTS

The PI-RADS v1 and v2 score differed in 52% of patients (32/61) and in 39% of lesions (35/90). On a lesion basis, the reason for the differences were related to sum score in v1 vs. categorical system in v2 in 51% (18/35) of lesions, cutoff between PI-RADS 4 and 5 based on lesion size in v2 as opposed to the sum score in v1 in 31% (11/35) and were inconclusive in 17% (6/35). The RP subgroup indicates enhanced detection of PCas with GS 3+3 and GS 3+4 in v2.

CONCLUSION

PI-RADS scores of prostatic lesions frequently differed between v1 and v2, the major reasons for these differences being score-related. In men undergoing RP, PI-RADS v2 improved detection of low risk PCa, but did not increase accuracy for discrimination of GS 3+4 vs. GS≥4+3 compared to v1. Urologists should be aware of the system-related differences when interpreting PI-RADS scores.

Significant reduction in positive surgical margin rate after laparoscopic radical prostatectomy by application of the modified surgical margin recommendations of the 2009 International Society of Urological Pathology consensus

OBJECTIVES

To verify retrospectively the margin status and analyse the location and characteristics of positive surgical margins (PSMs) in patients undergoing radical prostatectomy (RP), by a central pathology review, based on the consensus conference 2009 updated margin criteria from the International Society of Urological Pathology (ISUP).

PATIENTS AND METHODS

The detailed PSM characteristics of 441 patients who underwent laparoscopic RP (LRP) between 1999 and 2007 were centrally reviewed with regard to location, number, Gleason score at the PSM and tumour width. Predictors of PSMs and the impact of several PSM characteristics on clinical outcomes were examined. Patient characteristics were compared using the chi-squared test. Differences in recurrence-free survival (RFS) rates were analysed using the log-rank test and presented as Kaplan-Meier survival curves. Univariable and multivariable Cox regression analysis for the prediction of RFS was performed.

RESULTS

Central pathology review using the updated PSM definition according to ISUP 2009, resulted in reclassification of a substantial number of patients with PSMs (n = 113, 26.6%) as R0. Several PSM characteristics with a higher risk of biochemical recurrence (BCR) were identified as the strongest independent predictors of RFS: pathological stage; Gleason score; and the presence of multiple PSMs (hazard ratio [HR] 1.78; 95% confidence interval [CI] 1.08-2.96; P = 0.025). Further analysis replacing the location of PSM by the width categories of PSM showed that a PSM >3 mm was an independent predictor of RFS (HR 1.72; 95% CI 1.08-2.72; P = 0.022).

CONCLUSIONS

The impact of PSMs after LRP for prostate cancer remains unclear. PSMs in the present cohort of patients undergoing LRP had different characteristics and conferred different risks of BCR. A better understanding of PSM characteristics and a careful standardized pathological evaluation is needed to adequately counsel patients with respect to prognosis and adjuvant therapy after LRP.

T2- and diffusion-weighted magnetic resonance imaging at 3T for the detection of prostate cancer with and without endorectal coil: An intraindividual comparison of image quality and diagnostic performance

OBJECTIVES

To intraindividually compare image quality and diagnostic performance of multiparametric MRI (mpMRI) at 3T for the detection of prostate cancer (PCa) using a pelvic phased-array coil (PAC) and a combined endorectal and pelvic phased-array coil (ERC-PAC).

METHODS

Forty-five patients were prospectively included and received mpMRI of the prostate using a PAC and an ERC-PAC during one imaging session. Two radiologists evaluated image quality and the most suspicious lesion according to the PI-RADS scoring system. Results of MRI-TRUS-fusion biopsy of the prostate served as reference standard. Patient comfort and acceptance were assessed using a standardized questionnaire.

RESULTS

Overall image quality for T2WI was rated significantly better with an ERC-PAC compared to a PAC (p=0.0038). The weighted kappa for PI-RADS scores for T2WI and DWI with a PAC and an ERC-PAC was 0.70 and 0.73, respectively. For a PI-RADS sum score including T2WI and DWI the area under the curve with a PAC and an ERC-PAC were 0.95-0.99 and 0.93-0.97, respectively (p=0.1395).

CONCLUSION

For T2WI and DWI performed at 3T index PCa lesion identification and evaluation did not differ significantly with both coil setups. Patients preferred MRI without an ERC. Therefore, the use of an ERC may be omitted in a prostate cancer detection setting.

Retrospective Analysis of Fifth-Line Targeted Therapy Efficacy in Patients with Metastatic Renal Cell Carcinoma

OBJECTIVES

Current evidence of sequence-targeted therapy (TT) for patients with metastatic renal cell carcinoma (mRCC) beyond fourth-line is sparse. The aim of this study was to describe the efficacy and toxicity of fifth-line TT in patients with mRCC.

METHODS

Out of 406 patients treated in first-line, 25 patients (6.16%) with more than 4 lines of TT were retrospectively reviewed at a German academic high-volume cancer center. Response was assessed by the use of standard Response Evaluation Criteria in Solid Tumors version 1.0, and toxicity was graded according to the Common Toxicity Criteria for Adverse Events version 3.0. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Cox proportional hazard models were applied to explore predictors of PFS and OS in univariable and multivariable analyses.

RESULTS

Disease control rate for fifth-line treatment was 20%. Median OS from the beginning of first-line therapy was 50.2 months (IQR (interquartile range) 38.9-76.7). Median OS from the time of initiation of fifth-line therapy was 6.2 months (IQR 3.1-23.8). Median PFS for fifth-line TT was 4.1 months (IQR 1.81-9.07) and did not correlate to treatment response in first-line TT.

CONCLUSIONS

Highly selected patients might benefit from fifth-line treatment independently from treatment response in first-line TT.

MRI-guided core needle biopsy of the prostate: acceptance and side effects

PURPOSE

We aimed to study side effects, complications, and patient acceptance of magnetic resonance imaging-guided real-time biopsy (MRI-GB) of the prostate.

METHODS

Fifty-four men (49-78 years) with elevated prostate-specific antigen after at least one negative systematic transrectal ultrasound-guided biopsy (TRUS-GB) were included in a prospective clinical study. Suspicious areas on images were selectively sampled by obtaining a median of four specimens (range, 1-9 specimens) using MRI-GB. In TRUS-GB, a median of 10 specimens (range, 6-14 specimens) were obtained. Telephone interviews were conducted one week after outpatient MRI-GB, asking patients about pain and side effects (hematuria, hemospermia, rectal bleeding, fever, and chills) of the two biopsy procedures and which of the two procedures they preferred. Multinomial regression analysis and Fisher's exact test was used to test for differences.

RESULTS

MRI-GB was preferred by 65% (35/54), and 82% (44/54) would undergo MRI-GB again. Pain intensity (P = 0.005) and bleeding duration (P = 0.004) were significantly lower for MRI-GB compared with TRUS-GB. Hematuria was less common after MRI-GB compared with TRUS-GB (P = 0.006). A high correlation was given between bleeding intensity and bleeding duration for TRUS-GB (r=0.77) and pain intensity and pain duration for MRI-GB (r=0.65). Although hemospermia, rectal hemorrhage, fever, and chills were less common in MRI, they showed no statistically significant difference.

CONCLUSION

MRI-GB of the prostate seems to have fewer side effects and less pain intensity than TRUS-GB and was preferred by the majority of patients.

Prostate cancer detection on transrectal ultrasonography-guided random biopsy despite negative real-time magnetic resonance imaging/ultrasonography fusion-guided targeted biopsy: reasons for targeted biopsy failure

OBJECTIVE

To examine the value of additional transrectal ultrasonography (TRUS)-guided random biopsy (RB) in patients with negative magnetic resonance imaging (MRI)/ultrasonography (US) fusion-guided targeted biopsy (TB) and to identify possible reasons for TB failure.

PATIENTS AND METHODS

We conducted a subgroup analysis of 61 men with prostate cancer (PCa) detected by 10-core RB but with a negative TB, from a cohort of 408 men with suspicious multiparametric magnetic resonance imaging (mpMRI) between January 2012 and January 2015. A consensus re-reading of mpMRI results (using Prostate Imaging Reporting and Data System [PI-RADS] versions 1 and 2) for each suspicious lesion was performed, with the image reader blinded to the biopsy results, followed by an unblinded anatomical correlation of the lesion on mpMRI to the biopsy result. The potential reasons for TB failure were estimated for each lesion. We defined clinically significant PCa according to the Epstein criteria and stratified patients into risk groups according to the European Association of Urology guidelines.

RESULTS

Our analysis showed that RB detected significant PCa in 64% of patients (39/61) and intermediate-/high-risk PCa in 57% of patients (35/61). The initial mpMRI reading identified 90 suspicious lesions in the cohort. Blinded consensus re-reading of the mpMRI led to PI-RADS score downgrading of 45 lesions (50%) and upgrading of 13 lesions (14%); thus, negative TB could be explained by falsely high initial PI-RADS scores for 32 lesions (34%) and sampling of the target lesion by RB in the corresponding anatomical site for 36 out of 90 lesions (40%) in 35 of 61 patients (57%). Sampling of the target lesion by RB was most likely for lesions with PI-RADS scores of 4/5 and Gleason scores (GS) of ≥7. A total of 70 PCa lesions (67% with GS 6) in 44 patients (72%) were sampled from prostatic sites with no abnormalities on mpMRI.

CONCLUSION

In cases of TB failure, RB still detected a high rate of significant PCa. The main reason for a negative TB was a TB error, compensated for by positive sampling of the target lesion by the additional RB, and the second reason for TB failure was a falsely high initial PI-RADS score. The challenges that arise for both MRI diagnostics and prostate lesion sampling are evident in our data and support the integration of RB into the TB workflow.

Added Value of Multiparametric Ultrasonography in Magnetic Resonance Imaging and Ultrasonography Fusion-guided Biopsy of the Prostate in Patients With Suspicion for Prostate Cancer

OBJECTIVE

To analyze whether magnetic resonance imaging-ultrasonography (MRI-US) fusion-guided biopsy detects more and clinical significant prostate cancer (PCa) in comparison to conventional transrectal US-guided prostate biopsy (PBX) and to investigate if multiparametric (mp) US during MRI-US fusion can further characterize mpMRI-suspected lesions according to the prostate MRI reporting and data system (PI-RADS).

METHODS

From January 2012 to January 2014, 169 patients with a median of 2 negative conventional PBX and/or initially or consistently elevated prostate-specific antigen levels were prospectively included and underwent 3 T mpMRI. Real-time MRI-US fusion scan was used to biopsy the mpMRI-targeted lesions (n = 316). Scanning by mpUS, including B-mode, power Doppler, strain elastography, and contrast-enhanced US was performed to further characterize those lesions and to score by US modalities resulting in an mpUS score. Afterward, a conventional 10-core PBX was performed. PCa detection based on the results of targeted and conventional PBX was estimated. Performances of single US modalities were analyzed. The mpUS score was also investigated for PCa and PI-RADS score prediction.

RESULTS

Among 169 patients, 71 PCa (42%) were detected. From these 71 cases, clinically significant PCa (Gleason score ≥7) were detected exclusively by MRI-US fusion in 31 from 46 cases (67.4%). The highest sensitivity was observed in contrast-enhanced US (85%) and elastography (80%). The mpUS score predicts PCa and PI-RADS score with an overall accuracy of 86% and 80%, respectively.

CONCLUSION

MRI-US fusion-guided PBX detects more clinically significant PCa compared with conventional TRUS. The mpUS score correlates with PI-RADS in PCa prediction.

The detection of significant prostate cancer is correlated with the Prostate Imaging Reporting and Data System (PI-RADS) in MRI/transrectal ultrasound fusion biopsy

PURPOSE

To evaluate the performance of real-time MRI/ultrasound (MRI/US) fusion-guided targeted biopsy (TB) in men with primary and repeat biopsies and correlate the prostate cancer detection rate (CDR) with the PI-RADS score.

METHODS

Analysis included 408 consecutive men with primary and prior negative biopsies who underwent TB and 10-core random biopsy (RB) between January 2012 and January 2015. TB was performed with a real-time MRI/US fusion platform with sensor-based registration. Clinically significant PCa was defined as Gleason score (GS) ≥ 7 or GS 6 with maximal cancer core length ≥ 4 mm for TB and according to Epstein criteria for RB.

RESULTS

The overall CDR was 56 % (227/408). The CDR for primary biopsy was 74 % (60/81) and 57 % (67/117), 49 % (62/126), 45 % (38/84) for patients with 1, 2 and ≥ 3 prior negative biopsies. CDRs correlated with PI-RADS 2/3/4/5 were 16 % (5/32), 26 % (29/113), 62 % (94/152) and 89 % (99/111), respectively. The rates of significant tumors in relation to PI-RADS 2/3/4/5 were 60 % (3/5), 66 % (19/29), 74 % (70/94), 95 % (94/99). In 139 (61 %) cases with radical prostatectomy (RP), the rates of ≥ pT3 tumors in correlation with PI-RADS 4 and 5 were 20 % (11/56) and 49 % (32/65). PI-RADS constituted the strongest predictor of significant PCa detection (p < 0.007).

CONCLUSIONS

Real-time MRI/US fusion-guided TB combined with RB improved PCa detection in patients with primary and repeat biopsies. The CDR was strongly correlated with a rising PI-RADS score, values of 4 and 5 increasing the detection of clinically significant tumors and leading to a higher histological stage after RP.

[Real-time MRI/US fusion-guided biopsy in biopsy-naïve and pre-biopsied patients with suspicion for prostate cancer]

BACKGROUND

Magnetic resonance imaging (MRI)/ultrasound (US) fusion-guided biopsy detects more prostate cancer (PCa) than transrectal US (TRUS)-guided biopsy in patients with an indication for prostate re-biopsy. The aim of this study was a) to compare the detection rates of MRI/US fusion-guided biopsy with conventional TRUS in a double centre cohort and b) to investigate the influence of the number of pre-biopsies on the PCa detection rate.

MATERIAL AND METHODS

In the period from January 2012 to July 2014, 310 consecutive patients gave written informed consent and underwent 3 Tesla MRI scans of the prostate. All patients had at least one PCa suspicious lesion in the MRI and were biopsied by MRI/US fusion followed by a conventional 10-core biopsy of the prostate. Detection rates based on technique, Gleason score and number of pre-biopsies were calculated.

RESULTS

The overall detection rate of the study was 51% (158 patients). Among these 158 patients a histopathological Gleason score of 6 was detected in 60 patients (38%), a Gleason score of 7 in 54 patients (34%) and a Gleason score≥8 in 44 patients (28%). MRI/US fusion-guided biopsy detected 110 (69.7%) of the overall detected 158 PCa. TRUS-guided biopsy detected a higher rate of Gleason score 6 (54%) and a lower rate of Gleason score≥8 (15%) lesions in comparison to 38% Gleason 6 and 28% Gleason≥8 in the MRI/US fusion-guided biopsy, respectively. Furthermore, a lower Gleason score was observed in patients with more than one pre-biopsy. The detection rate in biopsy-naïve patients undergoing MRI/US fusion was 75% (40 patients) among 75% detected Gleason score≥7.

CONCLUSION

MRI/US fusion-guided biopsy detected more PCa and also more clinically significant cancer than conventional TRUS. In our cohort patients with more than one pre-biopsy showed lower Gleason scores. The included patients with an initial MRI/US fusion-guided biopsy should be further investigated.

[Real-time MRI/US fusion-guided biopsy improves detection rates of prostate cancer in pre-biopsied patients]

BACKGROUND

According to the guidelines of the European Association of Urology (EAU) on prostate cancer (PCa) in 2013, patients with increasing prostate-specific antigen (PSA) levels, suspicious digital rectal examination (DRE) or high-grade prostatic intraepithelial neoplasia after negative prostate biopsy (PB) should undergo a repeat biopsy. Low cancer detection rates in the repeat biopsy illuminate the dilemma of the international gold standard of transrectal ultrasound (TRUS) guided PB in the detection of PCa. Our study evaluated the combination of TRUS and prostate magnetic resonance imaging (MRI) and its reported high sensitivities and high specificities by using real-time MRI/US fusion-guided biopsy. The detection of clinically significant PCa was investigated.

MATERIAL AND METHODS

128 consecutive patients in the period of January 2012 to August 2013 were included. All patients had at least one TRUS-guided biopsy with negative findings and the clinical indication for a systematic re-biopsy. Prior to the MRI/US fusion all patients underwent a 3 Tesla prostate MRI without endorectal coil. The MRI data were uploaded to a modern US system. The B-mode, power-mode, elastography and CEUS imaging were used to classify the suspicious lesions from the MRI on a scale of 0-3 and a US sum score was calculated. The lesion was consecutively biopsied by real-time MRI/US fusion followed by a systematic 10 core biopsy.

RESULTS

Among 128 patients 51 PCa could be detected (39.8%). From these 51 PCa cases, clinically significant PCa was detected by MRI/US fusion-guided biopsy as follows: Gleason score >7 in 9 of 10 patients; Gleason score=7 in 14 of 20 patients and Gleason score <7 in 13 of 21 patients. A positive correlation was shown between the US sum score and the associated PI-RADS score in 65 patients in whom lesions were classified by PI-RADS. A positive correlation was further shown between the US sum score and the Gleason score of all suspicious and biopsied lesions. MRI/US fusion and TRUS-guided biopsy combined, detected 30 of 51 PCa; 6 of 51 PCa were detected by MRI/US fusion alone and 15 of 51 PCa by conventional TRUS-guided biopsy alone.

CONCLUSION

Real-time MR/US fusion increases detection rates of PCa in patients undergoing repeat biopsy. Especially, clinically significant PCa with a Gleason score ≥ 7 were almost exclusively detected by MR/US fusion-guided biopsy.

[Detection of prostate cancer by real-time MR/ultrasound fusion-guided biopsy: 3T MRI and state of the art sonography]

PURPOSE

Multiparametric MRI of the prostate is a noninvasive diagnostic method with high sensitivity and specificity for prostate cancer. The aim of this study is to evaluate whether prostate cancer detection rates of transrectal ultrasound (TRUS)-guided biopsy may be improved by an image fusion of state-of-the-art ultrasound (CEUS, elastography) and MR (T2w, DWI) imaging.

MATERIALS AND METHODS

32 consecutive patients with a history of elevated PSA levels and at least one negative TRUS-guided biopsy with clinical indication for a systematic re-biopsy underwent multiparametric 3 T MRI without endorectal coil. MR data (T2w) were uploaded to a modern sonography system and image fusion was performed in real-time mode during biopsy. B-mode, Doppler, elastography and CEUS imaging were applied to characterize suspicious lesions detected by MRI. Targeted biopsies were performed in MR/US fusion mode followed by a systematic standard TRUS-guided biopsy. Detection rates for both methods were calculated and compared using the Chi²-test.

RESULTS

Patient age was not significantly different in patients with and without histologically confirmed prostate cancer (65.2 ± 8.0 and 64.1 ± 7.3 age [p = 0.93]). The PSA value was significantly higher in patients with prostate cancer (15.5 ± 9.3 ng/ml) compared to patients without cancer (PSA 10.4 ± 9.6 ng/ml; p = 0.02). The proportion of histologically confirmed cancers in the study group (n = 32) of the MR/US fusion biopsy (11/12; 34.4 %) was significantly higher (p = 0.01) in comparison to the TRUS systematic biopsy (6/12; 18.8 %).

CONCLUSION

Real-time MR/US image fusion may enhance cancer detection rates of TRUS-guided biopsies and should therefore be studied in further larger studies.

Areas suspicious for prostate cancer: MR-guided biopsy in patients with at least one transrectal US-guided biopsy with a negative finding--multiparametric MR imaging for detection and biopsy planning

PURPOSE

To prospectively investigate the incremental value of multiparametric magnetic resonance (MR) imaging compared with standard T2-weighted imaging for biopsy planning.

MATERIALS AND METHODS

The study was approved by the institutional review board; informed consent was obtained. Consecutive patients underwent T2-weighted imaging supplemented with multiparametric 1.5-T MR imaging, consisting of hydrogen 1 ((1)H) MR spectroscopy, diffusion-weighted (DW) imaging, and contrast material-enhanced MR imaging. Quantitative parameters were calculated: (choline plus creatine)-to-citrate ratio, apparent diffusion coefficient, and volume transfer constant and exchange rate constant. The prostate was divided into 20 standardized areas. Each area was classified as benign, inconclusive, or suspicious at T2-weighted imaging, followed by quantitative evaluation of all inconclusive and suspicious areas with multiparametric MR imaging. MR-guided biopsy was performed in lesions classified as suspicious for cancer with at least one of the techniques after transfer to three-dimensional T2-weighted images. Diagnostic parameters were calculated on a per-lesion and per-patient basis for all combinations of T2-weighted imaging with multiparametric MR imaging.

RESULTS

Fifty-four patients had a median of two prior transrectal ultrasonographic biopsies with negative findings. Each patient had a median of three suspicious lesions. Prostate cancer was demonstrated in 21 of 54 patients. Biopsy was performed in 178 lesions; 53 were positive for prostate cancer. Detection rates and test negative results, respectively, were as follows: T2-weighted imaging, 70% and 50%; T2-weighted imaging and (1)H MR spectroscopy, 81% and 32%; T2-weighted imaging and contrast-enhanced MR imaging, 83% and 29%; T2-weighted imaging and DW imaging, 85% and 30%; T2-weighted imaging, (1)H MR spectroscopy, and contrast-enhanced MR imaging, 91% and 13%; T2-weighted imaging, (1)H MR spectroscopy, and DW imaging, 94% and 15%; T2-weighted imaging, DW imaging, and contrast-enhanced MR imaging, 94% and 13%; T2-weighted imaging, (1)H MR spectroscopy, DW imaging, and contrast-enhanced MR imaging, 100% and 0%.

CONCLUSION

Only the combination of T2-weighted imaging with all three multiparametric techniques depicts all identifiable prostate cancers; a double combination with DW imaging and (1)H MR spectroscopy or contrast-enhanced MR imaging misses 6%, while reasonably reducing the number of areas needing biopsy.

Retrospective analysis of prostate cancer recurrence potential with tissue metabolomic profiles

BACKGROUND

In clinical care of prostate cancer patients, an improved method to assess the risk of recurrence after surgical treatment is urgently needed. We aim to retrospectively evaluate the ability of ex vivo tissue magnetic-resonance-spectroscopy-based metabolomic profiles to estimate the risk of recurrence.

METHODS

PCa recurrence is defined biochemically as the detection of serum PSA after radical prostatectomy. Sixteen consecutive PCa-recurrent cases, those with an initial PSA increase of 0.69 +/- 0.26 ng/ml monitored 47.7 +/- 2.6 months after prostatectomy were paired by age and Gleason score with cases without recurrence of the same pathological and clinical stages (n = 16/each). We analyzed ex vivo intact-tissue spectroscopy results from these 48 individuals at the time of prostatectomy at 14T. From these spectra, we identified the 27 most common and intense spectral metabolic regions for statistical analyses.

RESULTS

Principal component analysis (PCA) on these spectral regions from cases of clinical-stage-matched groups with and without recurrence identified four pathology-related principal components. Canonical analysis of these four and the first nine principal components for cases in the two groups defined metabolomic profiles as the canonical score that can differentiate the two groups with statistical significance. By applying the coefficients from PCA and canonical analysis to the pathological-stage-matched groups, recurrence was predicted with an accuracy of 78%.

CONCLUSIONS

Results indicate the potential of tissue metabolomic profiles measured with ex vivo spectroscopy to identify PCa aggressiveness in terms of cancer recurrence. With further study, this may greatly contribute to the future design of clinical strategy for personalized treatment of PCa patients.