International Society of Urological Pathology (ISUP) Consensus Conference on Handling and Staging of Radical Prostatectomy Specimens. Working group 1: specimen handling

Application of ultrasound imaging biomarkers (HistoScanning™) improves staging reliability of prostate biopsies

Objective

Imaging biomarkers like HistoScanning™ augment the informative value of ultrasound. Analogue image-guidance might improve the diagnostic accuracy of prostate biopsies and reduce misclassifications in preoperative staging and grading.

Results

Comparison of 77 image-guided versus 88 systematic prostate biopsies revealed that incorrect staging and Gleason misclassification occurs less frequently in image-guided than in systematic prostate biopsies. Systematic prostate biopsies (4–36 cores, median 12 cores) tended to detect predominantly unilateral tumors (39% sensitivity, 90.9% specificity, 17.5% negative and 50% positive predictive values). Bilateral tumors were diagnosed more frequently by image-guided prostate biopsies (87.9% sensitivity, 72.7% specificity, 50% negative and 96.8% positive predictive values). Regarding the detection of lesions with high Gleason scores ≥ 3 + 4, systematic prostate and image-guided biopsies yielded sensitivity and specificity rates of 66.7% vs 93.5%, 86% vs 64.5%, as well as negative and positive predictive values of 71.2% vs 87%, and 83.3% vs 79.6%, respectively. Potential reason for systematic prostate biopsies missing the correct laterality and the correct Gleason score was a mismatch between the biopsy template and the respective pathological cancer localization. This supports the need for improved detection techniques such as ultrasound imaging biomarkers and image-adapted biopsies.

A novel technique for biobanking of large sections of radical prostatectomy specimens

AIMS

Harvesting of unfixed tissue from radical prostatectomy specimens for research purposes is challenging. Many prostate cancers cannot be identified at gross inspection, and this tumour is notoriously multifocal and heterogeneous. We aimed to develop a technique to allow detailed topographic analysis and the sampling of a sufficient amount of tumour without jeopardising clinical reporting.

METHODS AND RESULTS

A custom-made double-bladed knife was utilised for cutting a 4-mm-thick horizontal section of the prostate. The slices were split into segments that were frozen in gel, cryosections were cut, and RNA integrity numbers (RINs) were analysed. Sections were cut from all blocks of 20 cases, and the cutting time was monitored. Slides were scanned, and the slices were digitally reconstructed. Cutting frozen sections of an entire slice took 79-253 min (mean 162 min). Tumour was detected in frozen sections of 85% (17/20) of cases and in 46% (72/155) of blocks. The morphological quality was determined to be excellent, and RIN values were high (mean 8.9).

CONCLUSIONS

This novel protocol for biobanking of fresh tissue from prostatectomy specimens provides sufficient tumour material for research purposes, while also enabling reporting of histopathology. The harvesting of a full tissue slice facilitates studies of tumour multifocality and heterogeneity.

Prognostic Significance of Percentage and Architectural Types of Contemporary Gleason Pattern 4 Prostate Cancer in Radical Prostatectomy

The International Society of Urological Pathology (ISUP) 2014 consensus meeting recommended a novel grade grouping for prostate cancer that included dividing Gleason score (GS) 7 into grade groups 2 (GS 3+4) and 3 (GS 4+3). This division of GS 7, essentially determined by the percent of Gleason pattern (GP) 4 (< or >50%), raises the question of whether a more exact quantification of the percent GP 4 within GS 7 will yield additional prognostic information. Modifications were also made by ISUP regarding the definition of GP 4, now including 4 main architectural types: cribriform, glomeruloid, poorly formed, and fused glands. This study was conducted to analyze the prognostic significance of the percent GP 4 and main architectural types of GP 4 according to the 2014 ISUP grading criteria in radical prostatectomies (RPs). The cohort included 585 RP cases of GS 6 (40.2%), 3+4 (49.0%), and 4+3 (10.8%) prostate cancers. Significantly different 5-year biochemical recurrence (BCR)-free survival rates were observed among GS 6 (99%, 95% confidence interval [CI]: 97%-100%), 3+4 (81%, 95% CI: 76%-86%), and 4+3 (60%, 95% CI: 45%-71%) cancers (P<0.01). Dividing the GP 4 percent into quartiles showed a 5-year BCR-free survival of 84% (95% CI: 78%-89%) for 1% to 20%, 74% (95% CI: 62%-83%) for 21% to 50%, 66% (95% CI: 50%-78%) for 51% to 70%, and 32% (95% CI: 9%-59%) for >70% (P<0.001). Among the GP 4 architectures, cribriform was the most prevalent (43.7%), and combination of architectures with cribriform present was more frequently observed in GS 4+3 (60.3%). Glomeruloid was mostly (67.1%) seen combined with other GP 4 architectures. Unlike the other GP 4 architectures, glomeruloid as the sole GP 4 was observed only as a secondary pattern (ie, 3+4). Among patients with GS 7 cancer, the presence of cribriform architecture was associated with decreased 5-year BCR-free survival when compared with GS 7 cancers without this architecture (68% vs. 85%, P<0.01), whereas the presence of glomeruloid architecture was associated with improved 5-year BCR-free survival when compared with GS 7 cancers without this architecture (87% vs. 75%, P=0.01). However, GS 7 disease having only the glomeruloid architecture had significantly lower 5-year BCR-free survival than GS 6 cancers (86% vs. 99%, P<0.01). Multivariable Cox proportional hazards regression model for factors associated with BCR among GS 7 cancers identified age (hazard ratio [HR] 0.95, P<0.01), preoperative prostate-specific antigen (HR 1.07, P<0.01), positive surgical margin (HR 2.70, P<0.01), percent of GP 4 (21% to 50% [HR 2.21], 51% to 70% [HR 2.59], >70% [HR 6.57], all P<0.01), presence of cribriform glands (HR 1.78, P=0.02), and presence of glomeruloid glands (HR 0.43, P=0.03) as independent predictors. In conclusion, our study shows that increments in percent of GP 4 correlate with increased risk for BCR supporting the ISUP recommendation of recording the percent of GP 4 in GS 7 prostate cancers at RP. However, additional larger studies are needed to establish the optimal interval for reporting percent GP 4 in GS 7 cancers. Among the GP 4 architectures, cribriform independently predicts BCR, whereas glomeruloid reduces the risk of BCR. Distinction should be made between cribriform and glomeruloid architectures, despite glomeruloid being considered as an early stage of cribriform, as cribriform confers a higher risk for poorer outcome.

Diagnostic value and relative weight of sequence-specific magnetic resonance features in characterizing clinically significant prostate cancers

Purpose

To assess the diagnostic weight of sequence-specific magnetic resonance features in characterizing clinically significant prostate cancers (csPCa).

Materials and methods

We used a prospective database of 262 patients who underwent T2-weighted, diffusion-weighted, and dynamic contrast-enhanced (DCE) imaging before prostatectomy. For each lesion, two independent readers (R1, R2) prospectively defined nine features: shape, volume (V_Max), signal abnormality on each pulse sequence, number of pulse sequences with a marked (S_Max) and non-visible (S_Min) abnormality, likelihood of extracapsular extension (ECE) and PSA density (dPSA). Overall likelihood of malignancy was assessed using a 5-level Likert score. Features were evaluated using the area under the receiver operating characteristic curve (AUC). csPCa was defined as Gleason ≥7 cancer (csPCa-A), Gleason ≥7(4+3) cancer (csPCa-B) or Gleason ≥7 cancer with histological extraprostatic extension (csPCa-C),

Results

For csPCa-A, the Signal1 model (S_Max+S_Min) provided the best combination of signal-related variables, for both readers. The performance was improved by adding V_Max, ECE and/or dPSA, but not shape. All models performed better with DCE findings than without.

When moving from csPCa-A to csPCa-B and csPCa-C definitions, the added value of V_Max, dPSA and ECE increased as compared to signal-related variables, and the added value of DCE decreased.

For R1, the best models were Signal1+ECE+dPSA (AUC = 0,805 [95%CI:0,757–0,866]), Signal1+V_Max+dPSA (AUC = 0.823 [95%CI:0.760–0.893]) and Signal1+ECE+dPSA [AUC = 0.840 (95%CI:0.774–0.907)] for csPCa-A, csPCA-B and csPCA-C respectively. The AUCs of the corresponding Likert scores were 0.844 [95%CI:0.806–0.877, p = 0.11], 0.841 [95%CI:0.799–0.876, p = 0.52]) and 0.849 [95%CI:0.811–0.884, p = 0.49], respectively.

For R2, the best models were Signal1+V_Max+dPSA (AUC = 0,790 [95%CI:0,731–0,857]), Signal1+V_Max (AUC = 0.813 [95%CI:0.746–0.882]) and Signal1+ECE+V_Max (AUC = 0.843 [95%CI: 0.781–0.907]) for csPCa-A, csPCA-B and csPCA-C respectively. The AUCs of the corresponding Likert scores were 0. 829 [95%CI:0.791–0.868, p = 0.13], 0.790 [95%CI:0.742–0.841, p = 0.12]) and 0.808 [95%CI:0.764–0.845, p = 0.006]), respectively.

Conclusion

Combination of simple variables can match the Likert score’s results. The optimal combination depends on the definition of csPCa.

[CCAFU french national guidelines 2016-2018 on prostate cancer]

OBJECTIVES

The purpose of the guidelines national committee CCAFU was to propose updated french guidelines for localized and metastatic prostate cancer (PCa).

METHODS

A Medline search was achieved between 2013 and 2016, as regards diagnosis, options of treatment and follow-up of PCa, to evaluate different references with levels of evidence.

RESULTS

Epidemiology, classification, staging systems, diagnostic evaluation are reported. Disease management options are detailed. Recommandations are reported according to the different clinical situations. Active surveillance is a major option in low risk PCa. Radical prostatectomy remains a standard of care of localized PCa. The three-dimensional conformal radiotherapy is the technical standard. A dose of > 74Gy is recommended. Moderate hypofractionation provides short-term biochemical control comparable to conventional fractionation. In case of intermediate risk PCa, radiotherapy can be combined with short-term androgen deprivation therapy (ADT). In case of high risk disease, long-term ADT remains the standard of care. ADT is the backbone therapy of metastatic disease. In men with metastases at first presentation, upfront chemotherapy combined with ADT should be considered as a new standard. In case of metastatic castration-resistant PCa (mCRPC), new hormonal treatments and chemotherapy provide a better control of tumor progression and increase survival.

CONCLUSIONS

These updated french guidelines will contribute to increase the level of urological care for the diagnosis and treatment for prostate cancer. © 2016 Elsevier Masson SAS. All rights reserved.

Impact of the Prostate Imaging Reporting and Data System, Version 2, on MRI Diagnosis for Extracapsular Extension of Prostate Cancer

OBJECTIVE

The purpose of this study is to validate the Prostate Imaging Reporting and Data System, version 2 (PI-RADSv2), in assessing extracapsular extension (ECE), compared with PI-RADS, version 1 (PI-RADSv1).

MATERIALS AND METHODS

A total of 210 patients with clinically localized prostate cancer underwent MRI and radical prostatectomy. Two readers independently interpreted the MR images. In PI-RADSv1, 5-point ECE risk scoring was used. In PI-RADSv2, ECE criteria included morphologic features and a tumor-capsule contact length (CL) greater than 10 mm. The diagnostic performance of each PI-RADS version and the cutoff CL were evaluated.

RESULTS

ECE was found in 56 patients (26.7%). In PI-RADSv1, maximal accuracy was achieved with a risk score of 3 or greater. At this threshold, positive findings on PI-RADSv1 and PI-RADSv2 were identified in 21.0-34.3% and 49.0-51.4% of patients, respectively. Compared with PI-RADSv1, PI-RADSv2 had higher negative predictive values (84.9-89.1% vs 96.3-97.1%, respectively; p = 0.003 and 0.021, for each reader). PI-RADSv1 and PI-RADSv2 had positive predictive values of 56.9-70.5% and 49.1-50.5%, respectively (p = 0.025 and 0.300, respectively). Interobserver kappa values for PI-RADSv1 and PI-RADSv2 were 0.511 and 0.781, respectively. The best cutoff CL was greater than 10 mm among patients without morphologic features of ECE. For patients positive for ECE on the basis of PI-RADSv2 but not PI-RADSv1, 73.3-74.1% of prostate cancer cases with a biopsy Gleason score of 7 or less and 35.7-44.4% of cases with a biopsy Gleason score of 8 or higher were overstaged.

CONCLUSION

PI-RADSv2 reduces understaging and improves interobserver agreement in ECE assessment. However, overstaging is a concern, and the biopsy Gleason score may have a complementary role in reducing overstaging.

Stiffness of benign and malignant prostate tissue measured by shear-wave elastography: a preliminary study

OBJECTIVES

To measure benign and malignant prostate tissue stiffness using shear-wave elastography (SWE).

METHODS

Thirty consecutive patients underwent transrectal SWE in the axial and sagittal planes before prostatectomy. After reviewing prostatectomy specimens, two radiologists measured stiffness in regions corresponding to cancers, lateral and median benign peripheral zone (PZ) and benign transition zone (TZ).

RESULTS

Cancers were stiffer than benign PZ and TZ. All tissue classes were stiffer on sagittal than on axial imaging, in TZ than in PZ, and in median PZ than in lateral PZ. At multivariate analysis, the nature of tissue (benign or malignant; P < 0.00001), the imaging plane (axial or sagittal; P < 0.00001) and the location within the prostate (TZ, median PZ or lateral PZ; P = 0.0065) significantly and independently influenced tissue stiffness. On axial images, the thresholds maximising the Youden index in TZ, lateral PZ and median PZ were respectively 62 kPa, 33 kPa and 49 kPa. On sagittal images, the thresholds were 76 kPa, 50 kPa and 72 kPa, respectively.

CONCLUSIONS

SWE can distinguish prostate malignant and benign tissues. Tissue stiffness is influenced by the imaging plane and the location within the gland.

KEY POINTS

• Prostate cancers were stiffer than the benign peripheral zone • All tissue classes were stiffer on sagittal than on axial imaging • All tissue classes were stiffer in the transition zone than in the peripheral zone • All tissue classes were stiffer in the median than in the lateral peripheral zone • Taking into account imaging plane and zonal anatomy can improve cancer detection.

Incidental Prostate Adenocarcinoma in Cystoprostatectomy Specimens: Partial Versus Complete Prostate Sampling

BACKGROUND

The rate of incidental prostate adenocarcinoma (PCa) detection in radical cystoprostatectomy (RCP) varies widely, ranging from 15% to 54%. Such variability may be explained by institutional differences in prostate grossing protocols. Either partial or complete submission of the prostate gland in RCP may result in detection of clinically insignificant or significant incidental PCa. The aim of the study was to compare the clinical significance of PCa in RCP specimens in partial versus complete sampling.

MATERIAL

Seventy-two out of 158 RCP cases showed incidental PCa. The pathologic features, including Gleason score, margin status, extraprostatic extension (EPE), seminal vesicle invasion (SVI), PCa stage, and tumor volume, were assessed.

RESULTS

The 72 cases were divided into partial (n = 21, 29.1%) and complete sampling (n = 51, 70.8%) groups. EPE was detected in 13/72 (18.1%) with 11/13 (84.6%) cases in the complete group. Positive margins were present in 11/72 (15.3%) with 9/11 (81.8%) in the complete group. SVI was detected in 4/72 (5.6%) with 3/4 (75.0%) in the complete group. Overall, 4/72 (5.6%) had a Gleason score >7, all of which were in the complete group.

CONCLUSION

Our data suggest that complete sampling of the prostate may be the ideal approach to grossing RCP specimens, allowing for greater detection of clinically significant incidental PCa.

Length of capsular contact on prostate MRI as a predictor of extracapsular extension: which is the most optimal sequence?

Background Length of capsular contact (LCC) is a promising biomarker for predicting extracapsular extension (ECE), but the most optimal magnetic resonance imaging (MRI) sequence for measuring LCC is yet to be determined. Purpose To evaluate LCC using different MRI sequences for determining ECE in prostate cancer. Material and Methods A total of 185 patients underwent prostate MRI followed by radical prostatectomy. LCC was measured separately on T2-weighted (T2W) images, apparent diffusion coefficient (ADC) maps, and dynamic contrast-enhanced (DCE) MRI. LCCs (LCC_T2, LCC_ADC, LCC_DCE, and LCC_max [greatest value of 3 LCCs]) were compared between sequences using Wilcoxon signed rank test and was tested for determining ECE using the Mann-Whitney U test, ROC curve analysis, and logistic regression analysis. Results There were no significant differences among LCCs ( P = 0.333-0.837). All LCCs were significantly greater in patients with ECE ( P < 0.001). The optimal threshold value for predicting ECE was >14, >13, >12, and >14 mm for LCC_T2, LCC_ADC, LCC_DCE, and LCC_max, respectively. LCC_max yielded the highest area under the curve (0.895) which was significantly greater than that by LCC_ADC (0.858, P = 0.030). Otherwise, there were no significant difference between LCCs ( P = 0.052-0.985). At univariate analysis, age, clinical stage, PSA, Gleason score, and all LCCs were significantly associated with ECE ( P < 0.001-0.040). At multivariate analysis, GS ( P ≤ 0.008) and all LCCs ( P < 0.001) were independently predictive factors. Conclusion LCC measured on any sequence was significantly different in patients with and without ECE and was independently associated with the presence of ECE. Although LCC_max showed the greatest ability to predict ECE, there was relatively equivalent performance among different MRI sequences.

Reporting the margin in pancreaticoduodenectomies: R0 versus R1

AIM

This study was conducted to analyze the changes in margin positivity in pancreaticoduodenectomies, on using a standardized protocol, which bread loafs the pancreas and duodenum in the axial plane for adenocarcinomas arising in the pancreatic head, ampulla, terminal common bile duct (CBD), and duodenum, and then to assess whether these tumor subsets involve the margins in different ways.

METHODS

The analysis was performed on 70 consecutive specimens, the pre-protocol specimens serving as the control group.

RESULTS AND CONCLUSIONS

Tumors originating from the pancreatic head, ampulla, terminal CBD, and duodenum showed a consistent increase in their R1 incidence, post-protocol. Ampullary tumors showed the greatest upward change in R1 positivity. The highest incidence of margin positivity was seen in pancreatic head adenocarcinomas (80%), then distal CBD tumors (60%), and finally the ampullary tumors (39%). In pancreatic head adenocarcinomas, R1 increased from 55% to 80%, distal CBD from 50% to 60%, and ampullary from 17% to 39%. Duodenal adenocarcinomas had no R1 in both pre- and post-protocol groups. The tumors also had different patterns of margin involvement. Ampullary tumors involved only the posterior margin, pancreatic adenocarcinomas involved the superior mesenteric vein (SMV) groove more often than the posterior margin, and distal CBD tumors involved the posterior margin and SMV groove equally. The size of the tumor made a significant difference in pancreatic head carcinomas with tumor size less than or equal to 2 cm, showing an R1 incidence of 38%, while those above 2 cm had an R1 incidence of 68%.

Predictive factors associated with biochemical recurrence following radical prostatectomy for pathological T2 prostate cancer with negative surgical margins

OBJECTIVE

The aim of this study was to determine factors associated with the development of biochemical recurrence (BCR) following radical prostatectomy in patients with pathological T2 prostate cancer and negative surgical margins.

MATERIALS AND METHODS

This retrospective multicentre cohort study included 1252 consecutive patients with pT2 pN0/Nx and negative surgical margins on radical prostatectomy and without any adjuvant treatment, performed in three Belgian centres. BCR-free survival curves were estimated using the Kaplan-Meier method. Univariate and multivariate analyses using the Cox proportional hazards model were performed to determine clinical and pathological predictive factors of BCR in this group of patients.

RESULTS

In total, 910 patients were included. BCR occurred in 107 patients (11.8%) at a median follow-up of 108 months. Overall 5 and 10 year BCR-free survival rates were 90% and 87%, respectively. On the multivariate analyses, serum prostate-specific antigen (PSA) level (p = .001) and surgical Gleason score of 7 or above (p = .001) were significantly associated with BCR in men with pathological T2 prostate cancer with negative surgical margins. Perineural invasion and capsular infiltration were not risk factors for recurrence.

CONCLUSIONS

This study identified unfavourable risk factors in patients with pathological T2 and negative surgical margins following radical prostatectomy. The results suggest that patients with a surgical Gleason score of 7 or higher, unknown lymph-node status and high PSA values are at increased risk of recurrence.

The Impact of Downgrading from Biopsy Gleason 7 to Prostatectomy Gleason 6 on Biochemical Recurrence and Prostate Cancer Specific Mortality

PURPOSE

Gleason score is one of the most important prognostic indicators for prostate cancer. Downgrading from biopsy Gleason score 7 to radical prostatectomy Gleason score 6 occurs commonly and yet to our knowledge the impact on survival outcomes is unknown. We examined biochemical recurrence and prostate cancer specific mortality risk in a large cohort evaluated by a single group of expert urological pathologists.

MATERIALS AND METHODS

Of 23,918 men who underwent radical prostatectomy at our institution between 1984 and 2014, 10,236 with biopsy and radical prostatectomy Gleason score 6 or 7 without upgrading were included in analysis. The cohort was divided into 3 groups, including group 1-biopsy and radical prostatectomy Gleason score 6 in 6,923 patients (67.6%), group 2-Gleason score 7 downgraded to radical prostatectomy Gleason score 6 in 648 (6.3%) and group 3-biopsy and radical prostatectomy Gleason score 7 in 2,665 (26.0%). Biochemical recurrence and prostate cancer specific mortality risks were compared using Cox regression and competing risk analyses adjusting for clinicopathological variables.

RESULTS

At a median followup of 5 years (range 1 to 29), 992 men experienced biochemical recurrence and 95 had died of prostate cancer. Biochemical recurrence-free survival in downgraded cases (group 2) was better than in group 3 cases, which had Gleason score 7 on biopsy and radical prostatectomy (p <0.001), but worse than group 1 cases, which had Gleason score 6 on biopsy and radical prostatectomy (p <0.001). Downgrading was independently associated with biochemical recurrence (adjusted HR 1.87, p <0.0001) but not with prostate cancer specific mortality (adjusted HR 1.65, p = 0.636).

CONCLUSIONS

Downgrading from biopsy Gleason score 7 to radical prostatectomy Gleason score 6 was an independent predictor of biochemical recurrence but not prostate cancer specific mortality, likely due to the presence of minor amounts of Gleason pattern 4.

Determination of the Association Between T2-weighted MRI and Gleason Sub-pattern: A Proof of Principle Study

RATIONALE AND OBJECTIVES

The study aimed to determine the relationship between T2-weighted magnetic resonance imaging (MRI) signal and histologic sub-patterns in prostate cancer areas with different Gleason grades.

MATERIALS AND METHODS

MR images of prostates (n = 25) were obtained prior to radical prostatectomy. These were processed as whole-mount specimens with tumors and the peripheral zone was annotated digitally by two pathologists. Gleason grade 3 was the most prevalent grade and was subdivided into packed, intermediate, and sparse based on gland-to-stroma ratio. Large cribriform, intraductal carcinoma, and small cribriform glands (grade 4 group) were separately annotated but grouped together for statistical analysis. The log MRI signal intensity for each contoured region (n = 809) was measured, and pairwise comparisons were performed using the open-source software R version 3.0.1.

RESULTS

Packed grade 3 sub-pattern has a significantly lower MRI intensity than the grade 4 group (P < 0.00001). Sparse grade 3 has a significantly higher MRI intensity than the packed grade 3 sub-pattern (P < 0.0001). No significant difference in MRI intensity was observed between the Gleason grade 4 group and the sparse sub-pattern grade 3 group (P = 0.54). In multivariable analysis adjusting for peripheral zone, the P values maintained significance (packed grade 3 group vs grade 4 group, P < 0.001; and sparse grade 3 sub-pattern vs packed grade 3 sub-pattern, P < 0.001).

CONCLUSIONS

This study demonstrated that T2-weighted MRI signal is dependent on histologic sub-patterns within Gleason grades 3 and 4 cancers, which may have implications for directed biopsy sampling and patient management.

A Phase II, Randomized, Open-Label Study of Neoadjuvant Degarelix versus LHRH Agonist in Prostate Cancer Patients Prior to Radical Prostatectomy

Purpose: Degarelix, a new gonadotropin-releasing hormone (GnRH) receptor antagonist with demonstrated efficacy as first-line treatment in the management of high-risk prostate cancer, possesses some theoretical advantages over luteinizing hormone-releasing hormone (LHRH) analogues in terms of avoiding "testosterone flare" and lower follicle-stimulating hormone (FSH) levels. We set out to determine whether preoperative degarelix influenced surrogates of disease control in a randomized phase II study.Experimental Design: Thirty-nine patients were randomly assigned to one of three different neoadjuvant arms: degarelix only, degarelix/bicalutamide, or LHRH agonist/bicalutamide. Treatments were given for 3 months before prostatectomy. Patients had localized prostate cancer and had chosen radical prostatectomy as primary treatment. The primary end point was treatment effect on intratumoral dihydrotestosterone levels.Results: Intratumoral DHT levels were higher in the degarelix arm than both the degarelix/bicalutamide and LHRH agonist/bicalutamide arms (0.87 ng/g vs. 0.26 ng/g and 0.23 ng/g, P < 0.01). No significant differences existed for other intratumoral androgens, such as testosterone and dehydroepiandrosterone. Patients in the degarelix-only arm had higher AMACR levels on immunohistochemical analysis (P = 0.01). Serum FSH levels were lower after 12 weeks of therapy in both degarelix arms than the LHRH agonist/bicalutamide arm (0.55 and 0.65 vs. 3.65, P < 0.01), and inhibin B levels were lower in the degarelix/bicalutamide arm than the LHRH agonist/bicalutamide arm (82.14 vs. 126.67, P = 0.02).Conclusions: Neoadjuvant degarelix alone, compared with use of LHRH agonist and bicalutamide, is associated with higher levels of intratumoral dihydrotestosterone, despite similar testosterone levels. Further studies that evaluate the mechanisms behind these results are needed. Clin Cancer Res; 23(8); 1974-80. ©2016 AACR.

Evaluating Prostate Cancer Using Fractional Tissue Composition of Radical Prostatectomy Specimens and Pre-Operative Diffusional Kurtosis Magnetic Resonance Imaging

BACKGROUND

Evaluating tissue heterogeneity using non-invasive imaging could potentially improve prostate cancer assessment and treatment.

METHODS

20 patients with intermediate/high-risk prostate cancer underwent diffusion kurtosis imaging, including calculation of apparent diffusion (Dapp) and kurtosis (Kapp), prior to radical prostatectomy. Whole-mount tissue composition was quantified into: cellularity, luminal space, and fibromuscular stroma. Peripheral zone tumors were subdivided according to Gleason score.

RESULTS

Peripheral zone tumors had increased cellularity (p<0.0001), decreased fibromuscular stroma (p<0.05) and decreased luminal space (p<0.0001). Gleason score ≥4+3 tumors had significantly increased cellularity and decreased fibromuscular stroma compared to Gleason score ≤3+4 (p<0.05). In tumors, there was a significant positive correlation between median Kapp and cellularity (ρ = 0.50; p<0.05), and a negative correlation with fibromuscular stroma (ρ = -0.45; p<0.05). In normal tissue, median Dapp had a significant positive correlation with luminal space (ρ = 0.65; p<0.05) and a negative correlation with cellularity (ρ = -0.49; p<0.05). Median Kapp and Dapp varied significantly between tumor and normal tissue (p<0.0001), but only median Kapp was significantly different between Gleason score ≥4+3 and ≤3+4 (p<0.05).

CONCLUSIONS

Peripheral zone tumors have increased cellular heterogeneity which is reflected in mean Kapp, while normal prostate has a more homogeneous luminal space and cellularity better represented by Dapp.

The prognostic significance of the 2014 International Society of Urological Pathology (ISUP) grading system for prostate cancer

The 2005 International Society of Urological Pathology (ISUP) modified Gleason grading system was further amended in 2014 with the establishment of grade groupings (ISUP grading). This study examined the predictive value of ISUP grading, comparing results with recognised prognostic parameters.Of 3700 men undergoing radical prostatectomy (RP) reported at Aquesta Pathology between 2008 and 2013, 2079 also had a positive needle biopsy available for review. We examined the association between needle biopsy 2014 ISUP grade and 2005 modified Gleason score, tumour volume, pathological stage of the subsequent RP tumour, as well as biochemical recurrence-free survival (BRFS). The median age was 62 (range 32-79 years). Median serum prostate specific antigen was 5.9 (range 0.4-69 ng/mL). For needle biopsies, 280 (13.5%), 1031 (49.6%), 366 (17.6%), 77 (3.7%) and 325 (15.6%) were 2014 ISUP grades 1-5, respectively. Needle biopsy 2014 ISUP grade showed a significant association with RP tumour volume (p < 0.001), TNM pT and N stage (p < 0.001) and BRFS (p < 0.001). Multivariate analysis using Cox proportional hazards regression model showed serum prostate specific antigen (PSA) at the time of diagnosis and ISUP grade >2 to be significantly associated with BRFS.This study provides evidence of the prognostic significance of ISUP grading for thin core needle biopsy of prostate.

Does the distance between tumor and margin in radical prostatectomy specimens correlate with prognosis: relation to tumor location

The posterior half of the prostate has a smooth well-defined edge unlike anteriorly. Often, tumor extends close to the posterior margin, where it is controversial whether pathologists should measure the distance between the tumor and the margin. There are no published data regarding the significance of a close margin factoring in the anatomical location within the radical prostatectomy (RP). We identified 158 RPs with 39 anterior-predominant carcinomas and 119 cases with posterior-predominant cancer. Distances between the tumor and inked margin were measured with an ocular micrometer. Eighty-seven cases had no progression with a minimum 6-year follow-up (median, 8; range, 6-9). Eighteen cases had progression with a median time to progression of 2 years with all men progressing within 6 years after RP. There was no statistically significant difference in the risk of progression relative to distance of tumor to the posterior margin (P=.09). The mean distance of tumor to the anterior margin for the cases that progressed was 0.6 mm (median, 0.5 mm; range, 0.05-1.18) compared to 1.9 mm (median, 1.1; range, 0.02-4) for the cases that did not progress (P=.02). Of 7 cases with anterior-predominant tumors that progressed, 5 had tumor located less than 1 mm from the anterior margin. In conclusion, if cancer is present less than 1 mm from the anterior margin, there is an increased tendency to recur, and this finding should be included in pathology reports. However, close margins posteriorly are not clinically significant and should not be reported.

Ablative therapy for people with localised prostate cancer: a systematic review and economic evaluation

BACKGROUND

For people with localised prostate cancer, active treatments are effective but have significant side effects. Minimally invasive treatments that destroy (or ablate) either the entire gland or the part of the prostate with cancer may be as effective and cause less side effects at an acceptable cost. Such therapies include cryotherapy, high-intensity focused ultrasound (HIFU) and brachytherapy, among others.

OBJECTIVES

This study aimed to determine the relative clinical effectiveness and cost-effectiveness of ablative therapies compared with radical prostatectomy (RP), external beam radiotherapy (EBRT) and active surveillance (AS) for primary treatment of localised prostate cancer, and compared with RP for salvage treatment of localised prostate cancer which has recurred after initial treatment with EBRT.

DATA SOURCES

MEDLINE (1946 to March week 3, 2013), MEDLINE In-Process & Other Non-Indexed Citations (29 March 2013), EMBASE (1974 to week 13, 2013), Bioscience Information Service (BIOSIS) (1956 to 1 April 2013), Science Citation Index (1970 to 1 April 2013), Cochrane Central Register of Controlled Trials (CENTRAL) (issue 3, 2013), Cochrane Database of Systematic Reviews (CDSR) (issue 3, 2013), Database of Abstracts of Reviews of Effects (DARE) (inception to March 2013) and Health Technology Assessment (HTA) (inception to March 2013) databases were searched. Costs were obtained from NHS sources.

REVIEW METHODS

Evidence was drawn from randomised controlled trials (RCTs) and non-RCTs, and from case series for the ablative procedures only, in people with localised prostate cancer. For primary therapy, the ablative therapies were cryotherapy, HIFU, brachytherapy and other ablative therapies. The comparators were AS, RP and EBRT. For salvage therapy, the ablative therapies were cryotherapy and HIFU. The comparator was RP. Outcomes were cancer related, adverse effects (functional and procedural) and quality of life. Two reviewers extracted data and carried out quality assessment. Meta-analysis used a Bayesian indirect mixed-treatment comparison. Data were incorporated into an individual simulation Markov model to estimate cost-effectiveness.

RESULTS

The searches identified 121 studies for inclusion in the review of patients undergoing primary treatment and nine studies for the review of salvage treatment. Cryotherapy [3995 patients; 14 case series, 1 RCT and 4 non-randomised comparative studies (NRCSs)], HIFU (4000 patients; 20 case series, 1 NRCS) and brachytherapy (26,129 patients; 2 RCTs, 38 NRCSs) studies provided limited data for meta-analyses. All studies were considered at high risk of bias. There was no robust evidence that mortality (4-year survival 93% for cryotherapy, 99% for HIFU, 91% for EBRT) or other cancer-specific outcomes differed between treatments. For functional and quality-of-life outcomes, the paucity of data prevented any definitive conclusions from being made, although data on incontinence rates and erectile dysfunction for all ablative procedures were generally numerically lower than for non-ablative procedures. The safety profiles were comparable with existing treatments. Studies reporting the use of focal cryotherapy suggested that incontinence rates may be better than for whole-gland treatment. Data on AS, salvage treatment and other ablative therapies were too limited. The cost-effectiveness analysis confirmed the uncertainty from the clinical review and that there is no technology which appears superior, on the basis of current evidence, in terms of average cost-effectiveness. The probabilistic sensitivity analyses suggest that a number of ablative techniques are worthy of further research.

LIMITATIONS

The main limitations were the quantity and quality of the data available on cancer-related outcomes and dysfunction.

CONCLUSIONS

The findings indicate that there is insufficient evidence to form any clear recommendations on the use of ablative therapies in order to influence current clinical practice. Research efforts in the use of ablative therapies in the management of prostate cancer should now be concentrated on the performance of RCTs and the generation of standardised outcomes.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42012002461.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Clinical significance of pelvic lymph node status in prostate cancer: review of 1690 cases

To assess whether any relationship exists between the number of histologically examined lymph nodes and the detection of metastases in pelvic lymph node dissection (PLND) specimens taken from patients with radical prostatectomy (RP) for prostatic adenocarcinoma. 1690 cases of RP with PNLD were included in the study; 54 % of the patients were submitted to extended PLND (ePLND). Kaplan-Meier curves confirm the negative prognostic significance of nodal metastases on the overall patients' survival (P < 0.0001). Nodal metastases are significantly associated with older age of patients (P = 0.0466), higher pT status (P < 0.0001), higher Gleason score (P < 0.0001) and positive surgical margin (P < 0.0001). The frequency of nodal metastases is significantly increased in cases submitted to ePLND (P < 0.0001), presumably due to the significantly higher number of lymphnodes retrieved using this procedure (P < 0.0001). In addition, regardless of the extent of PLND procedure, entire histological examination of PLND specimens is significantly associated with a higher frequency of nodal metastases (P < 0.0001). When we considered only pN0 cases, 21 display adverse prognosis and died of disease during the follow-up. The number of pelvic lymphnodes examined is significantly lower in the group of patients who die of the disease compared to that of survivors (P = 0.0448). In addition, Kaplan-Meier analysis shows that patients with 10 or fewer examined lymphnodes have significantly shorter disease-specific survival (P = 0.0151). Our findings confirm the negative prognostic significance of N status in prostate cancer. We suggest the examination of a minimum number of 10 lymphnodes, together with entire PLND processing, for accurate assessment of N status.

Gleason Misclassification Rate Is Independent of Number of Biopsy Cores in Systematic Biopsy

OBJECTIVE

To compare the utility of saturation core biopsy and 12-core biopsy in detecting true Gleason grades, using final pathology in prostatectomy specimens as outcome measures, with a particular interest in Gleason upgrading.

PATIENTS AND METHODS

We compared the concordance rates of Gleason grades diagnosed on biopsies and prostatectomy specimens in 375 consecutive patients, including 106 saturation biopsies (18-33 cores, median = 20 cores) and 269 12-core biopsies. Grading bias was addressed by a central rereview of all cases that had discordance in reporting high Gleason grades (Gleason grade ≥ 4) on biopsies and prostatectomy specimens.

RESULTS

For patients with high Gleason grades on final pathology, saturation and 12-core biopsy schemes had a comparable sensitivity, specificity, negative and positive predictive values (72.5% vs 69.5%, 91.9% vs 97.6%, 64.2% vs 58.4%, and 94.3% vs 98.5%, respectively) in detecting high Gleason grades. On multivariate analysis, prebiopsy serum prostate-specific antigen and clinical T stage independently predicted Gleason upgrading; saturation biopsy was not a significant predictor. Approximately one-third of cases where high Gleason grade was not present in the biopsy were attributed to the confinement of high-grade tumors to unusual anatomic locations such as anterior lobes, apex, bladder neck, and parasagittal zones.

CONCLUSION

Our study showed that Gleason misclassification rate is independent of the number of biopsy cores in systematic biopsy. One of the reasons for missing high Gleason grade tumors on systematic biopsy was unusual tumor location outside of the biopsy grid, supporting the need for improved detection technique such as magnetic resonance imaging-guided targeted biopsies.

Quantitative Analysis of Prostate Multiparametric MR Images for Detection of Aggressive Prostate Cancer in the Peripheral Zone: A Multiple Imager Study

Purpose To assess the intermanufacturer variability of quantitative models in discriminating cancers with a Gleason score of at least 7 among peripheral zone (PZ) lesions seen at 3-T multiparametric magnetic resonance (MR) imaging. Materials and Methods An institutional review board-approved prospective database of 257 patients who gave written consent and underwent T2-weighted, diffusion-weighted, and dynamic contrast material-enhanced imaging before prostatectomy was retrospectively reviewed. It contained outlined lesions found to be suspicious for malignancy by two independent radiologists and classified as malignant or benign after correlation with prostatectomy whole-mount specimens. One hundred six patients who underwent imaging with 3-T MR systems from two manufacturers were selected (data set A, n = 72; data set B, n = 34). Eleven parameters were calculated in PZ lesions: normalized T2-weighted signal intensity, skewness and kurtosis of T2-weighted signal intensity, T2 value, wash-in rate, washout rate, time to peak (TTP), mean apparent diffusion coefficient (ADC), 10th percentile of the ADC, and skewness and kurtosis of the histogram of the ADC values. Parameters were selected on the basis of their specificity for a sensitivity of 0.95 in diagnosing cancers with a Gleason score of at least 7, and the area under the receiver operating characteristic curve (AUC) for the models was calculated. Results The model of the 10th percentile of the ADC with TTP yielded the highest AUC in both data sets. In data set A, the AUC was 0.90 (95% confidence interval [CI]: 0.85, 0.95) or 0.89 (95% CI: 0.82, 0.94) when it was trained in data set A or B, respectively. In data set B, the AUC was 0.84 (95% CI: 0.74, 0.94) or 0.86 (95% CI: 0.76, 0.95) when it was trained in data set A or B, respectively. No third variable added significantly independent information in any data set. Conclusion The model of the 10th percentile of the ADC with TTP yielded accurate results in discriminating cancers with a Gleason score of at least 7 among PZ lesions at 3 T in data from two manufacturers. (©) RSNA, 2016 Online supplemental material is available for this article.

Assessment of the circumferential margins, extraprostatic extension and Gleason score in radical prostatectomy specimens: Comparison of a partial embedding method with supplemental total inclusion of peripheral tissues

BACKGROUND

Recent data suggest that up to 21% of positive circumferential margins (PCM) and 47% of extraprostatic extension (EPE) samples may be missed when partial embedding methods are employed. Kim and colleagues (2009) suggested that total inclusion of the periphery (3mm rim) of the prostate prevented the failure to detect PCM and EPE.

DESIGN

Radical prostatectomy specimen (n=148) slides were reviewed after adoption of a protocol that included a ∼3 mm rim of peripheral tissues. We evaluated whether the analysis of supplemental slides of prostate periphery changed margin status, presence of EPE, Gleason score and extent of PCM and EPE.

RESULTS

Partial sampling resulted in missing 29% of PCM and 20% of EPE without using data from the supplemental slides of prostate periphery. Changes from focal to extensive disease were found in 11/21 (52%) cases of positive circumferential margins and in 5/13 (38%) cases of extraprostatic extension. Changes in the Gleason score were uncommon.

CONCLUSIONS

These results indicate the importance of including all the prostate peripheral tissue for microscopic analysis when partial embedding methods are adopted.

Ratio of Tumor to Normal Prostate Tissue Apparent Diffusion Coefficient as a Method for Quantifying DWI of the Prostate

OBJECTIVE

The purpose of this study was to investigate the ability of the apparent diffusion coefficient (ADC) ratio of tumor to normal prostate tissue to overcome inherent variability based on choice of b values, with whole-mount histopathologic analysis as the reference standard for tumor identification.

MATERIALS AND METHODS

Thirty-nine patients with prostate cancer underwent 3-T MRI, including DWI with b values of 0, 150, 750, and 1000 s/mm(2). ADC maps were derived from four b value combinations. Histologically derived ROIs were defined for prostate tumor and benign prostate tissue to generate a ratio. The concordance correlation coefficient was used to evaluate agreement and reproducibility at different b values. Bland-Altman plots were used to evaluate the pattern of relative measurement difference between b value combinations. The relationship between ADC values and Gleason score was tested by Spearman rank correlation.

RESULTS

ADC values varied depending on the b value combination selected. The concordance correlation coefficient was higher for ADC ratios (0.883; 95% CI, 0.816-0.927) compared with absolute ADC values for normal tissue (0.873; 95% CI, 0.799-0.921) and tumor (0.792; 95% CI, 0.688-0.864). The ADC ratio concordance correlation coefficient for transition zone tumors was considerably higher than that for the peripheral zone in all cases. Bland-Altman analysis showed higher variation for ADC maps incorporating a b value of zero for both ratio and absolute values. There was a stronger inverse relationship to Gleason score for ADC ratios (rho, -0.354 to -0.456) compared with absolute ADC values (rho, -0.117 to -0.379).

CONCLUSION

The use of a simple ratio of prostate tumor ADC to normal tissue ADC improved the concordance between different b value combinations and could provide a more robust means of assessing restricted diffusion in the prostate.

[Analysis and prognostic factors of the specimen of radical prostatectomy in prostate cancer]

OBJECTIVES

Handling and pathologic analysis of radical prostatectomy specimens are crucial to confirm the diagnosis of prostate cancer and evaluate prognostic criteria.

MATERIAL AND METHODS

A systematic review of the scientific literature was performed in the Medline database (PubMed), using different associations of the following keywords: prostate cancer; prostatectomy; specimen; handling; pathology; tumor staging; Gleason score; surgical margin; prognosis; frozen section; lymph node; biomarkers. A particular search was done on specimen management and characterization of tissue prognostic factors.

RESULTS

Handling of both radical prostatectomy specimen and lymph node dissection is standardized according to international criteria. Although the main histoprognostic factors are still Gleason score, pathologic staging and margin status, these criteria have been refined these last 10 years, allowing to improve the prediction of relapse after surgical treatment.

CONCLUSION

The standardization of handling and pathology reporting of radical prostatectomy specimens will be mandatory for treatment uniformization according to risk stratification in prostate cancer and personalization of therapeutic approaches.

Preoperative erectile function and the pathologic features of prostate cancer

Purpose

We evaluated whether preoperative erectile function is associated with pathologic features in the patients who underwent radical prostatectomy (RP).

Materials and Methods

We reviewed medical records of 1,743 men who underwent RP from November 2003 through May 2012. Of these, 50 patients who had prior hormone therapy and 272 patients who had lacking data of International Index of Erectile Function-5 (IIEF-5) were excluded. Men whose IIEF-5 was in the lower 25 percentile were assigned as Low Erectile Function group and the others were assigned as Control group. We compared pathologic features using univariable and multivariable logistic regression analysis between two groups.

Results

A total of 1,421 patients were included in the analysis. Patients’ age was 65.8 ± 6.7 years and prostate-specific antigen (PSA) was 12.8±16.1 ng/mL. Median and low 25 percentile of IIEF-5 were 14 and 8, respectively. Low Erectile Function group (IIEF-5<8) had higher risk to have high Gleason score (≥7(4+3), odds ratio (OR) 1.642, p<0.001) and large tumor volume (≥5 mL, OR 1.292, p=0.042). Even after adjusting age, year of surgery, body mass index, Charlson comorbidity index, PSA, clinical stage and biopsy Gleason score, Low Erectile Function group still had higher risk of high Gleason score (OR 1.910, p<0.001) and large tumor volume (OR 1.390, p=0.04) by multivariable logistic regressions.

Conclusions

Lower erectile function before RP was associated with higher Gleason’s score and larger tumor volume in final pathology. Thus, erectile function could be a surrogate barometer for prostate cancer aggressiveness.

African-American Men with Gleason Score 3+3=6 Prostate Cancer Produce Less Prostate Specific Antigen than Caucasian Men: A Potential Impact on Active Surveillance

PURPOSE

We assess the difference in prostate specific antigen production between African-American and Caucasian men with Gleason score 3+3=6 prostate cancer.

MATERIALS AND METHODS

We measured tumor volume in 414 consecutive radical prostatectomies from men with National Comprehensive Cancer Network(®) low risk prostate cancer (348 Caucasian, 66 African-American) who had Gleason score 3+3=6 disease at radical prostatectomy. We then compared clinical presentation, pathological findings, prostate specific antigen, prostate specific antigen density and prostate specific antigen mass (an absolute amount of prostate specific antigen in patient's circulation) between African-American and Caucasian men. The t-test and Wilcoxon rank sum were used for comparison of means.

RESULTS

African-American and Caucasian men had similar clinical findings based on age, body mass index and prostate specific antigen. There were no statistically significant differences between the dominant tumor nodule volume and total tumor volume (mean 0.712 vs 0.665 cm(3), p=0.695) between African-American and Caucasian men. Prostates were heavier in African-American men (mean 55.4 vs 46.3 gm, p <0.03). Despite the significantly greater weight of benign prostate tissue contributing to prostate specific antigen in African-American men, prostate specific antigen mass was not different from that of Caucasian men (mean 0.55 vs 0.558 μg, p=0.95). Prostate specific antigen density was significantly less in African-American men due to larger prostates (mean 0.09 vs 0.105, p <0.02).

CONCLUSIONS

African-American men with Gleason score 3+3=6 prostate cancer produce less prostate specific antigen than Caucasian men. African-American and Caucasian men had equal serum prostate specific antigen and prostate specific antigen mass despite significantly larger prostates in African-American men with all other parameters, particularly total tumor volume, being the same. This finding has practical implications in T1c cases diagnosed with prostate cancer due to prostate specific antigen screening. Lowering the prostate specific antigen density threshold in African-American men may account for this disparity, particularly in selecting patients for active surveillance programs.

Average Weight of Seminal Vesicles: An Adjustment Factor for Radical Prostatectomy Specimens Weighed With Seminal Vesicles

The International Society of Urological Pathology in 2010 recommended weighing prostates without seminal vesicles (SV) to include only prostate weight in prostate-specific antigen (PSA) density (PSAD) calculation, because SV do not produce PSA. Large retrospective cohorts exist with combined weight recorded that needs to be modified for retrospective analysis. Weights of prostates and SV were separately recorded in 172 consecutive prostatectomies. The average weight of SV and proportion of prostate weight from combined weight were calculated. The adjustment factors were then validated on databases of 2 other institutions. The average weight of bilateral SV was 6.4 g (range = 1-17.3 g). The prostate constituted on average 87% (range = 66% to 98%) of the total specimen weight. There was no correlation between patient age and prostate weight with SV weight. The best performing correction method was to subtract 6.4 g from total radical prostatectomy weight and to use this weight for PSAD calculation. The average weights of retrospective specimens weighed with SV were not significantly different between the 3 institutions. Using our data allowed calibration of the weights and PSAD between the cohorts weighed with and without SV. Thus, prostate weight in specimens including SV weight can be adjusted by subtracting 6.4 g, resulting in significant change of PSAD. Some institution-specific variations may exist, which could further increase the precision of retrospective analysis involving prostate weight and PSAD. However, unless institution-specific adjustment parameters are developed, we recommend that this correction factor be used for retrospective cohorts or in institutions where combined weight is still recorded.

Oncological outcomes following robotic-assisted radical prostatectomy in a multiracial Asian population

This study evaluates the oncological outcomes of RARP in a multiracial Asian population from a single institution. All suitable patients from 1st January 2003-30th June 2013 were identified from a prospectively maintained cancer registry. Peri-operative and oncological outcomes were analysed. Significance was defined as p < 0.05. There were n = 725 patients identified with a mean follow-up duration 28 months. The mean operative time, EBL and LOS were 186 min, 215 ml and 3 days, respectively. The pathological stage was pT2 in 68.6% (n = 497/725), pT3 in 31.3% (n = 227/725) and n = 1 patient with pT4 disease. The pathological Gleason scores (GS) were 6 in 27.9% (n = 202/725), GS 7 in 63.6% (n = 461/725) and GS ≥ 8 in 8.0 % (n = 58/725). The node positivity rate was 5.8% (n = 21/360). The positive margin rates were 31.0% (n = 154/497) and 70.9% (n = 161/227) for pT2 and pT3, respectively, and decreasing PSM rates are observed with surgical maturity. The biochemical recurrence rates were 9.7% (n = 48/497) and 34.2% (n = 78/228) for pT2 and pT3/T4, respectively. On multivariate analysis, independent predictors of BCR were pathological T stage and pathological Gleason score. Post-operatively, 78.5% (n = 569/725) of patients had no complications and 17.7% (n = 128/725) had minor (Clavien grade I-II) complications. This series, representing the largest from Southeast Asia, suggests that RARP can be a safe and oncologically feasible treatment for localised prostate cancer in an institution with moderate workload.

Difference between actual vs. pathology prostate weight in TURP and radical robotic-assisted prostatectomy specimen

INTRODUCTION

To investigate and highlight the effect of formaldehyde induced weight reduction in transurethral resection of prostate (TURP) and radical robotically-assisted prostatectomy (RALP) specimen as a result of standard chemical fixation.

MATERIALS AND METHODS

51 patients were recruited from January 2013 to June 2013 who either underwent a TURP (n=26) or RALP (n=25). Data was collected prospectively by the operating surgeon who measured the native, unfixed histology specimen directly after operation. The specimens were fixed in 10% Formaldehyde Solution BP and sent to the pathology laboratory where after sufficient fixation period was re-weighed.

RESULTS

Overall mean age 64.78 years, TURP mean age 68.31 years RALP mean age 61.12 years. We found that the overall prostatic specimen (n=51) weight loss after fixation was a mean of 11.20% (3.78 grams) (p ≤ 0.0001). Subgroup analysis of the native TURP chips mean weight was 16.15 grams and formalin treated mean weight was 14.00 grams (p ≤ 0.0001). Therefore, TURP chips had a mean of 13.32 % (2.15 grams) weight loss during chemical fixation. RALP subgroup unfixed specimen mean weight was 52.08 grams and formalin treated mean weight was 42.60 grams (p ≤ 0.0001), a 19.32 % (9.48 grams) mean weight reduction.

CONCLUSION

It has not been known that prostatic chips and whole human radical prostatectomy specimen undergo a significant weight reduction. The practical significance of the accurate prostate weight in patient management may be limited, however, it is agreed that this should be recorded correctly, as data is potential interest for research purposes and vital for precise documentation.

Multiparametric MRI Improves Accuracy of Clinical Nomograms for Predicting Extracapsular Extension of Prostate Cancer

OBJECTIVE

To compare the accuracy of multiparametric magnetic resonance imaging (MP-MRI) with the Partin tables and Memorial Sloan-Kettering (MSK) nomogram for predicting extracapsular extension (ECE) in prostate cancer and to create a tool for clinicians to estimate pathologic ECE risk.

METHODS

A retrospective review of 112 patients who underwent 3T MP-MRI of the prostate and radical prostatectomy was performed. Regression analyses were carried out to identify predictors of ECE. Predictive accuracy of models based on nomogram and MP-MRI were compared.

RESULTS

A total of 33 of patients (29%) had ECE on MP-MRI whereas 26 patients (23%) had ECE on final pathology. Mean age was 62.8 years and mean prostate-specific antigen was 8.2 ng/dL. MRI was a significant predictor of ECE that was independent of age, prostate-specific antigen, Gleason score, clinical stage, and percent positive cores on biopsy. Sensitivity, specificity, positive predictive value, and negative predictive value of MP-MRI for ECE were 84.6%, 87.2%, 66.7%, and 94.9%, respectively. Areas under the curve for Partin and MSK nomograms for predicting ECE were 0.85 and 0.86, respectively. Area under the curve increased to 0.92 and 0.94, respectively, when MP-MRI was added to each nomogram. We provide an online tool that integrates Partin or MSK nomogram results with ECE status determined from MRI to predict pathologic ECE. Within the typical range of risks for ECE provided by the clinical nomograms (ie, 15%-40%), MRI was useful for predicting pathologic ECE.

CONCLUSION

MP-MRI may be a useful adjunct for clinically staging prostate cancer. MP-MRI improved accuracy of existing clinical nomograms for prediction of pathologic ECE.

Reliability of sentinel node procedure for lymph node staging in prostate cancer patients at high risk for lymph node involvement

AIM

To investigate the reliability of a sentinel node (SN) procedure for nodal staging in prostate cancer (PCa) patients at high risk for lymph node (LN) involvement.

MATERIAL AND METHODS

Seventy-four patients with localized prostate adenocarcinoma, who were clinically node-negative and had a risk of LN involvement of ≥ 10% (Partin tables), were prospectively enrolled. Upon intraprostatic 99mTc-nanocolloid injection, they underwent planar scintigraphy and SPECT imaging. Surgical removal of the SN, located by means of a gamma probe, was completed with a superextended LN dissection (seLND) as a reference and followed by radical prostatectomy.

RESULTS

In total, 470 SN (median 6, IQR 3-9) were scintigraphically detected of which 371 (median 4, IQR 2-6) were located by gamma probe and selectively removed during surgery (79%). Histopathology confirmed LN metastases in 37 patients (50%) having 106 affected LN in total (median number per patient 2, IQR 1-4). Twenty-eight patients were node positive (N+) based on the analysis of the resected SN. However, the seLND that was performed as a reference revealed nine additional N+ patients resulting in a sensitivity of 76% (28/37). In total, 15 of 37 patients (41%) had metastases in SN only and could have been spared seLND to remove all affected nodes.

CONCLUSION

We found a relatively low sensitivity when addressing the SN procedure for nodal staging in PCa patients at high risk for LN involvement. Importantly, only less than half of the N+ patients could have been spared a seLND to remove all affected lymphoid tissue.

Positive surgical margins after radical prostatectomy: What should we care about?

PURPOSE

Positive surgical margins (PSMs) after radical prostatectomy (RP) are a known factor associated with biochemical recurrence (BCR) and raise the issue of adjuvant treatment by radiotherapy versus salvage treatment at recurrence. To help this choice, our study aimed to analyze BCR-free survival and factors associated with BCR in patients with PSM and undetectable postoperative prostate-specific antigen (PSA).

METHODS

Between 2005 and 2008, 630 patients had RP for localized prostate cancer in our center. We included patients with PSM, uninvaded nods, undetectable postoperative PSA and no adjuvant treatment. The 5-year BCR-free survival was calculated using Kaplan-Meier method. Logistic regression models were used to determine the factors associated with BCR in univariate and multivariate analyses (Cox model).

RESULTS

The PSM rate was 32.7 % (n = 206 patients), and 110 patients corresponded to the inclusion criteria. The median follow-up was 72 months. The BCR rate was 30 % with a 5-year BCR-free survival of 83.9 %. The factors significantly associated with BCR were preoperative PSA, predominance and percentage of Gleason 4, tumor volume, PSM length and predominance of Gleason 4 at the margin. In the multivariate analysis, the remaining two significant factors were PSM length [OR 4.35, 95 % CI (1.011-1.421), p = 0.037] and tumor volume [OR 4.29, 95 % CI (1.011-1.483), p = 0.038].

CONCLUSION

Over a 5-year follow-up, only one-third of patients experienced BCR. It might be reasonable to postpone adjuvant radiotherapy for patients with PSM and undetectable PSA after RP. Tumor volume and PSM length were associated with BCR and should be taken into account in the postoperative treatment management.

Early development of human lymphomas in a prostate cancer xenograft program using triple knock-out immunocompromised mice

BACKGROUND

There is an urgent need for preclinical models of prostate cancer; however, clinically relevant patient-derived prostate cancer xenografts (PDXs) are demanding to establish.

METHODS

Sixty-seven patients who were undergoing palliative transurethral surgery or radical prostatectomy for histologically confirmed, clinically relevant prostate cancer were included in the study. Fresh prostate cancer tissue was identified by frozen analysis in 48 patients. The cancer tissue was transplanted subcutaneously and under the renal capsule of NSG and NOG mice supplemented with human testosterone. All growing PDXs were evaluated by histology and immunohistochemistry.

RESULTS

Early assessment of the animals at least three months after transplantation included 27/48 (56.3%) eligible PDX cohorts. PDX growth was detected in 10/27 (37%) mouse cohorts. Eight of the ten PDXs were identified as human donor derived lymphomas, including seven Epstein Barr virus (EBV)-positive diffuse large B-cell lymphomas and one EBV-negative peripheral T-cell lymphoma. One sample consisted of benign prostatic tissue, and one sample comprised a benign epithelial cyst. Prostate cancer was not detected in any of the samples.

CONCLUSIONS

Tumors that arise within the first three months after prostate cancer xenografting may represent patient-derived EBV-positive lymphomas in up to 80% of the early growing PDXs when using triple knockout NSG immunocompromised mice. Therefore, lymphoma should be excluded in prostate cancer xenografts that do not resemble typical prostatic adenocarcinoma.

Variation between specialist uropatholgists in reporting extraprostatic extension after radical prostatectomy

Aims

Extraprostatic extension of prostate cancer in radical prostatectomy specimens significantly affects patient management. We evaluated the degree of interobserver variation between uropathologists at a tertiary referral teaching hospital in assessing the extraprostatic extension of prostate cancer in radical prostatectomy specimens.

Methods

Histopathological data from a consecutive series of 293 radical prostatectomy specimens (January 2007–December 2012) were reviewed. A subset of 50 consecutive radical prostatectomy cases originally staged as tumours confined to the prostate (pT2) or tumours extending into periprostatic tissue (pT3a) during this period were reviewed by four specialist uropathologists.

Results

Five consultant histopathologists reported these specimens with significant differences in the reported stage (p=0.0164) between pathologists. Double-blind review by 4 uropathologists of 50 consecutive radical prostatectomy cases showed a lack of consensus in 16/50 (32%) cases (κ score 0.58, moderate agreement). A consensus meeting was held, but consensus could still not be reached in 9/16 cases.

Conclusions

Our findings highlight variability in the reporting of pT stage in radical prostatectomy specimens even by specialist uropathologists. Assessment of extraprostatic extension has important implications for patient management and there is a need for more precise guidance.

Detection of the index tumour and tumour volume in prostate cancer using T2-weighted and diffusion-weighted magnetic resonance imaging (MRI) alone

OBJECTIVE

To examine the performance of T2-weighted (T2W) and diffusion-weighted (DW) magnetic resonance imaging (MRI) for detecting the index tumour in patients with prostate cancer and to examine the agreement between MRI and histology when assessing tumour volume (TV) and overall tumour burden.

PATIENTS AND METHODS

The study included 199 consecutive patients with biopsy confirmed prostate cancer randomised to MRI before radical prostatectomy from December 2009 to July 2012. MRI-detected tumours (MRTs) were ranked from 1 to 3 according to decreasing volume and were compared with histologically detected tumours (HTs) ranked from 1 to 3, with HT 1 = index tumour. Whole-mount section histology was used as a reference standard. The TVs of true-positive MRTs (MRTVs 1-3) were compared with the TVs found by histology (HTVs 1-3). All tumours were registered on a 30-sector map and by classifying each sector as positive/negative, the rate of true-positive and -negative sectors was calculated.

RESULTS

The detection rate for the HT 1 (index tumour) was 92%; HT 2, 45%; and HT 3, 37%. The MRTV 1-3 vs the HTV 1-3 were 2.8 mL vs 4.0 mL (index tumour, P < 0.001), 1.0 mL vs 0.9 mL (tumour 2, P = 0.413), and 0.6 mL vs 0.5 mL (tumour 3, P = 0.492). The rate of true-positive and -negative sectors was 50% and 88%, κ = 0.39.

CONCLUSION

A combination of T2W and DW MRI detects the index tumour in 92% of cases, although MRI underestimates both TV and tumour burden compared with histology.

Periprostatic fat thickness on MRI: correlation with Gleason score in prostate cancer

OBJECTIVE

The purpose of this study was to retrospectively evaluate the relationship between periprostatic fat thickness on MRI and Gleason score of prostate cancer using radical prostatectomy as the reference standard.

MATERIALS AND METHODS

This study included 190 patients (mean age [± SD], 66.9 ± 7.0 years) who underwent MRI before radical prostatectomy. Two radiologists measured the subcutaneous and periprostatic fat thickness on midsagittal T2-weighted MR images as the shortest perpendicular distance from the pubic symphysis to the skin and prostate, respectively. Subcutaneous and periprostatic fat along with age, height, weight, body mass index, and prostate-specific antigen (PSA) were correlated with Gleason score by using Pearson (r) or Spearman (ρ) correlation coefficients and compared between low- (Gleason score = 6) and high- (≥ 7) grade prostate cancer by using univariate and multivariate logistic regression analyses.

RESULTS

The mean subcutaneous and periprostatic fat thicknesses were 24.0 ± 8.4 mm and 5.0 ± 2.0 mm, respectively. The Gleason score was significantly correlated with age (ρ = 0.181, p = 0.012), PSA (ρ = 0.345, p < 0.001), and periprostatic fat thickness (ρ = 0.228, p = 0.002). Multivariate analysis revealed that age, height, PSA level, and periprostatic fat thickness (odds ratio, 1.331; 95% CI, 1.063-1.666) were independently predictive of high-grade (p ≤ 0.013) disease.

CONCLUSION

Periprostatic fat thickness on MRI showed a mild to modest but significant correlation with Gleason score of prostate cancer with radical prostatectomy as the reference standard and was an independent predictive factor for high-grade prostate cancer.

Final analysis of a prospective trial on functional imaging for nodal staging in patients with prostate cancer at high risk for lymph node involvement

PURPOSE

Accurate staging modalities to diagnose lymph node involvement in patients with prostate cancer (PCa) are lacking. We wanted to prospectively assess sensitivity, specificity, and positive predictive value (PPV) and negative predictive value of (11)C-choline positron emission tomography (PET)-computed tomography (CT) and diffusion-weighted (DW) magnetic resonance imaging (MRI) for nodal staging in patients with PCa at high risk for lymph node involvement.

MATERIAL AND METHODS

In total, 75 patients with a risk≥10% but<35% for lymph node (LN) metastases (Partin tables) who had N0 lesions based on the findings of contrast-enhanced CT scans were included. Patients underwent (11)C-choline PET-CT and DW MRI before surgery, which consisted of a superextended lymph node dissection followed by radical prostatectomy. LNs were serially sectioned and histopathologically examined after pankeratin staining. These results were used as the gold standard to compare with the imaging results.

RESULTS

Of 1,665 resected LNs (median = 21, range: 7-49), 106 affected LNs (median = 2, range: 1-10) were found in 37 of 75 patients (49%). On a region-based analysis, we found a low sensitivity of 8.2% and 9.5% and a PPV of 50.0% and 40.0% for (11)C-choline PET-CT and DW MRI, respectively. The patient-based analysis showed a sensitivity of 18.9% and 36.1% for and a PPV of 63.6% and 86.7% (11)C-choline PET-CT and DW MRI, respectively. Even when both imaging modalities were combined, sensitivity values remained too low to be clinically useful.

CONCLUSIONS

Because of the low sensitivity, there is no indication for routine clinical use of either (11)C-choline PET-CT or DW MRI for LN staging in patients with PCa, in whom CT scan findings were normal.

Robot-assisted radical prostatectomy: Multiparametric MR imaging-directed intraoperative frozen-section analysis to reduce the rate of positive surgical margins

PURPOSE

To investigate whether use of multiparametric magnetic resonance (MR) imaging-directed intraoperative frozen-section (IFS) analysis during nerve-sparing robot-assisted radical prostatectomy reduces the rate of positive surgical margins.

MATERIALS AND METHODS

This retrospective analysis of prospectively acquired data was approved by an institutional ethics committee, and the requirement for informed consent was waived. Data were reviewed for 134 patients who underwent preoperative multiparametric MR imaging (T2 weighted, diffusion weighted, and dynamic contrast-material enhanced) and nerve-sparing robot-assisted radical prostatectomy, during which IFS analysis was used, and secondary resections were performed when IFS results were positive for cancer. Control patients (n = 134) matched for age, prostate-specific antigen level, and stage were selected from a pool of 322 patients who underwent nerve-sparing robot-assisted radical prostatectomy without multiparametric MR imaging and IFS analysis. Rates of positive surgical margins were compared by means of the McNemar test, and a multivariate conditional logistic regression model was used to estimate the odds ratio of positive surgical margins for patients who underwent MR imaging and IFS analysis compared with control subjects.

RESULTS

Eighteen patients who underwent MR imaging and IFS analysis underwent secondary resections, and 13 of these patients were found to have negative surgical margins at final pathologic examination. Positive surgical margins were found less frequently in the patients who underwent MR imaging and IFS analysis than in control patients (7.5% vs 18.7%, P = .01). When the differences in risk factors are taken into account, patients who underwent MR imaging and IFS had one-seventh the risk of having positive surgical margins relative to control patients (adjusted odds ratio: 0.15; 95% confidence interval: 0.04, 0.61).

CONCLUSION

The significantly lower rate of positive surgical margins compared with that in control patients provides preliminary evidence of the positive clinical effect of multiparametric MR imaging-directed IFS analysis for patients who undergo prostatectomy.