The Impact of the 2005 International Society of Urological Pathology Consensus Conference on Standard Gleason Grading of Prostatic Carcinoma in Needle Biopsies

Prognostic Utility of the Gleason Grading System Revisions and Histopathological Factors Beyond Gleason Grade

Background

The International Society of Urological Pathology (ISUP) revised the Gleason system in 2005 and 2014. The impact of these changes on prostate cancer (PCa) prognostication remains unclear.

Objective

To evaluate if the ISUP 2014 Gleason score (GS) predicts PCa death better than the pre-2005 GS, and if additional histopathological information can further improve PCa death prediction.

Patients and Methods

We conducted a case–control study nested among men in the National Prostate Cancer Register of Sweden diagnosed with non-metastatic PCa 1998–2015. We included 369 men who died from PCa (cases) and 369 men who did not (controls). Two uro-pathologists centrally re-reviewed biopsy ISUP 2014 Gleason grading, poorly formed glands, cribriform pattern, comedonecrosis, perineural invasion, intraductal, ductal and mucinous carcinoma, percentage Gleason 4, inflammation, high-grade prostatic intraepithelial neoplasia (HGPIN) and post-atrophic hyperplasia. Pre-2005 GS was back-transformed using i) information on cribriform pattern and/or poorly formed glands and ii) the diagnostic GS from the registry. Models were developed using Firth logistic regression and compared in terms of discrimination (AUC).

Results

The ISUP 2014 GS (AUC = 0.808) performed better than the pre-2005 GS when back-transformed using only cribriform pattern (AUC = 0.785) or both cribriform and poorly formed glands (AUC = 0.792), but not when back-transformed using only poorly formed glands (AUC = 0.800). Similarly, the ISUP 2014 GS performed better than the diagnostic GS (AUC = 0.808 vs 0.781). Comedonecrosis (AUC = 0.811), HGPIN (AUC = 0.810) and number of cores with ≥50% cancer (AUC = 0.810) predicted PCa death independently of the ISUP 2014 GS.

Conclusion

The Gleason Grading revisions have improved PCa death prediction, likely due to classifying cribriform patterns, rather than poorly formed glands, as Gleason 4. Comedonecrosis, HGPIN and number of cores with ≥50% cancer further improve PCa death discrimination slightly.

Learning a Triplet Embedding Distance to Represent Gleason Patterns

Gleason grade stratification is the main histological standard to determine the severity and progression of prostate cancer. Nonetheless, there is a high variability on disease diagnosis among expert pathologists (kappa lower than 0.44). End-to-end deep representations have recently deal with the automatic classification of Gleason grades, where each grade is limited to namely code high-visual-variability sharing patterns among classes. Such limitation on models may be attributed to the relatively few labels to train the representation, as well as, to the natural imbalanced sets, available in clinical scenarios. To overcome such limitation, this work introduces a new embedding representation that learns intra and inter-Gleason relationships from more challenging class samples (grades tree and fourth). The proposed strategy implements a triplet loss scheme building a hidden embedding space that correctly differentiates close Gleason levels. The proposed approach shows promising results achieving an average accuracy of 74% to differentiate between degrees three and four. For classification of all degrees, the proposed approach achieves an average accuracy of 62%.

Exploration on Gleason score variation trend of patients with prostate carcinoma from 1996 to 2019: a retrospective single center study

Background

Gleason score (GS) is one of the stronger prognostic factors and is integral to the management of prostate carcinoma. Subsequent modifications, recommended by the International Society of Urological Pathology in 2005 and 2014, enabled accurate prediction of prognosis. The present study investigated GS variation trend of patients with prostate carcinoma from 1996 to 2019 and offered an overview of GS changes with age, specimen type, histopathological type and serum prostate specific antigen (PSA).

Methods

One thousand three hundred and seventy-six patients, admitted to Peking University People's Hospital in 1996 to 2019, were divided into 1996 to 2006, 2007 to 2015 and 2016 to 2019 groups. Data, including demographic characteristics, GS, primary and secondary grade and percentage of primary and secondary grade of each group, were collected and analyzed. The population distribution and average of GS was evaluated, after segmented and stratified by age, type of specimen, histopathological type and PSA.

Results

The average of age and PSA of each cohort had no obvious change. The average of total GS fluctuated among three cohorts with statistically significant differences. The distribution of age and PSA did not differ among cohorts. The distribution of total and primary GS shifted, with more patients detected as total GS higher than 6 (86.1%), and more primary grade higher than 3 (56.7%) in 2016-2019. After segmented and stratified by age, specimen type, histological type and PSA, the population percentage of GS over 6 was significantly higher in 2016-2019 than 1996-2006 and 2007-2015 in patients aged younger than 80 years (age <60, 89.6%, age 60-69, 82.0%, age 70-79, 87.7%). Patients, aged below 80 years in 2016-2019, were detected with higher total GS.

Conclusions

In the present study, GS in patients with prostate carcinoma showed a upward trend. Primary grade, age, serum PSA and specimen type were the main reasons for GS changing while secondary grade, tissue types and diagnostic criteria influenced less.

A grading dilemma; Gleason scoring system: Are we sufficiently compatible? A multi center study

Objective

Gleason scoring is the grading system which strongly predicts the prognosis of prostate cancer. However, even being one of the most commonly used systems, the presence of different interobserver agreement rates push the uropathologists update the definitons of the Gleason patterns. In this study, we aimed to determine the interobserver agreement variability among 7 general pathologists, and one expert uropathologist from 6 different centers.

Methods

A set of 50 Hematoxylin & Eosin stained slides from 41 patients diagnosed as prostate cancer were revised by 8 different pathologists. The pathologists were also grouped according to having their residency at the same institute or working at the same center. All pathologists' and the subgroups' Gleason scores were then compared for interobserver variability by Fleiss' and Cohen's kappa tests using R v3.2.4.

Results

There were about 8 pathologists from 6 different centers revised all the slides. One of them was an expert uropathologist with experience of 18 years. Among 7 general pathologists 4 had surgical pathology experience for over 5 years whilst 3 had under 5 years. The Fleiss' kappa was found as 0.54 for primary Gleason pattern, and 0.44 for total Gleason score (moderate agreement). The Fleiss' kappa was 0.45 for grade grouping system.

Conclusion

Assigning a Gleason score for a patient can be problematic because of different interobserver agreement rates among pathologists even though the patterns were accepted as well-defined.

Inter-observer variability amongst surgeons and radiologists in assessment of Guy's Stone Score and S.T.O.N.E. nephrolithometry score: A prospective evaluation

Objective

(a) To assess the inter-observer variability amongst surgeons performing percutaneous nephrolithotomy (PCNL) and radiologists for the Guy’s Stone Score (GSS) and S.T.O.N.E. (stone size [S], tract length [T], obstruction [O], number of involved calyces [N], and essence or stone density [E]) nephrolithometry score; (b) To determine which scoring system of the two is better for predicting the stone-free rate (SFR) after PCNL.

Patients, subjects and methods

Patients undergoing PCNL between February 2016 and September 2016 were prospectively enrolled. Preoperative computed tomography was done in all patients. The GSS and S.T.O.N.E. nephrolithometry score were independently calculated by eight surgeons and four radiologists. The patients were operated on by one of the surgeons (all were consultants). The Fleiss’ κ coefficient was used to assess agreement independently between the surgeons and radiologists. Receiver operating characteristic (ROC) curves were constructed for predicting the SFR using the average of the scores of the surgeons and radiologists separately.

Results

A total of 157 patients underwent PCNL. The SFR was 71.3% (112/157 patients). The Fleiss’ κ scores ranged from 0.51 to 0.88 (overall 0.79) for the S.T.O.N.E. score and 0.53–0.91 for the GSS, suggesting moderate to very good agreement. The ROC curve for the S.T.O.N.E. nephrolithometry scores of surgeons (area under the curve [AUC] = 0.806) as well as the radiologists (AUC = 0.810) had a higher predictive value for the SFR than the GSS of the surgeons (AUC = 0.738) and the radiologists (AUC = 0.747).

Conclusion

There is overall good agreement between surgeons and radiologists for both the GSS and S.T.O.N.E. nephrolithometry score. The S.T.O.N.E. score had a higher predictive value for the SFR than the GSS.

Abbreviations

AUC: area under the curve; GSS: Guy’s Stone Score; KUB: kidneys, ureters and bladder; NCCT: non-contrast CT; PCNL: Percutaneous nephrolithotomy; ROC: receiver operating characteristic; SFR: stone-free rate; S.T.O.N.E.: stone size [S], tract length [T], obstruction [O], number of involved calyces [N], and essence or stone density [E]

PROSTATE CANCER DETECTION USING HISTOPATHOLOGY IMAGES AND CLASSIFICATION USING IMPROVED RideNN

Medical industry reports prostate cancer as common and high among men and alarms the necessity for detecting prostate cancer for which the required morphology is extracted from the histopathology images. Commonly, the Gleason grading system remains a perfect factor for grading prostate cancer in men, but pathologists suffer from minute inter- and intra-observer variations. Thus, an automatic method for segmenting and classifying prostate cancer is modeled in this paper. The significance of the developed method is that the segmentation and classification are gland-oriented using the Color Space (CS) transformation and Salp Swarm Optimization Algorithm-based Rider Neural Network (SSA-RideNN). The gland region is considered as the morphology for cancer detection from which the maximal significant regions are extracted as features using multiple-kernel scale-invariant feature transform (MK-SIFT). Here, the RideNN classifier is trained optimally using the proposed Salp–Rider Algorithm (SRA), which is the integration of Salp Swarm Optimization Algorithm (SSA) and Rider Optimization Algorithm (ROA). The experimentation is performed using the histopathology images and the analysis based on sensitivity, accuracy, and specificity reveals that the proposed prostate cancer detection method acquired the maximal accuracy, sensitivity, and specificity of 0.8966, 0.8919, and 0.8596, respectively.

Risk of Gleason Score 3+4=7 prostate cancer upgrading at radical prostatectomy is significantly reduced by targeted versus standard biopsy

BACKGROUND

The aim of this study is to evaluate if multiparametric magnetic resonance (mpMRI)-transrectal ultrasound (TRUS) fusion targeted biopsy (TBx) versus untargeted standard biopsy (SBx) may decrease the rate of pathological upgrading of Gleason Score (GS) 3+4 prostate cancer (PCa) at radical prostatectomy (RP). We also evaluated the impact of percent pattern 4 and cribriform glands at biopsy in the risk of GS 3+4=7 upgrading.

METHODS

A total of 301 patients with GS 3+4 PCa on biopsy (159 SBx and 142 TBx) who underwent laparoscopic robot-assisted RP were sequentially enrolled. Histological data from RP sections were used as reference standard. The concordance of biopsy with pathological GS, as well as the GS 3+4 upgrading at RP were evaluated in different univariate and multivariate binary logistic regression models, testing age, PSA, fPSA%, tumor volume, PI-RADS, clinical stage, percentage of Gleason pattern 4 (GP) and/or presence of cribriform sub-type at biopsy.

RESULTS

Of the 301 biopsies, the median of GP 4 was 16% of the tissue. Minimal GP 4 (≤16%) cancers had a significant lower median volume (1.7 mL) than those with GP4 >16% (2.9 mL), (P<0.001). Pathological GS 3+4 was confirmed for 58.8% and 82.2% for SBx and TBx patients, respectively. The rate of upgraded and downgraded GS on SBx versus TBx was 38.8% vis. 16.7% and 1.8% and 2.1%, respectively. The rate of upgrading was significantly associated with the presence of GP4 >16% versus ≤16% (OR 4.4, 95% CI 1.4-12.0; P=0.021) and with the presence of cribriform sub-type at biopsy specimens (OR 6.2, 95% CI 2.2-18.7; P<0.001).

CONCLUSIONS

We demonstrated that TBx technique significantly reduced the risk of GS 3+4 upgrading at RP, compared to SBx one. The rate of upgrading was significantly associated with GP4>16%, mostly when cribriform sub-type was present at biopsy specimens.

Statistical Analysis of Survival Models Using Feature Quantification on Prostate Cancer Histopathological Images

BACKGROUND

Grading of prostatic adenocarcinoma is based on the Gleason scoring system and the more recently established prognostic grade groups. Typically, prostate cancer grading is performed by pathologists based on the morphology of the tumor on hematoxylin and eosin (H and E) slides. In this study, we investigated the histopathological image features with various survival models and attempted to study their correlations.

METHODS

Three texture methods (speeded-up robust features, histogram of oriented gradient, and local binary pattern) and two convolutional neural network (CNN)-based methods were applied to quantify histopathological image features. Five survival models were assessed on those image features in the context with other prostate clinical prognostic factors, including primary and secondary Gleason patterns, prostate-specific antigen levels, age, and clinical tumor stages.

RESULTS

Based on statistical comparisons among different image features with survival models, image features from CNN-based method with a recurrent neural network called CNN-long-short-term memory provided the highest hazard ratio of prostate cancer recurrence under Cox regression with an elastic net penalty.

CONCLUSIONS

This approach outperformed the other image quantification methods listed above. Using this approach, patient outcomes were highly correlated with the histopathological image features of the tissue samples. In future studies, we plan to investigate the potential use of this approach for predicting recurrence in a wider range of cancer types.

Landmarks in prostate cancer

The field of prostate cancer has been the subject of extensive research that has resulted in important discoveries and shaped our appreciation of this disease and its management. Advances in our understanding of the epidemiology, natural history, anatomy, detection, diagnosis, grading, staging, imaging, and management of prostate cancer have changed clinical practice and influenced guideline recommendations. The development of the Gleason score and subsequent modifications enabled accurate prediction of prognosis. Increased anatomical understanding and improved surgical techniques resulted in the development of nerve-sparing surgery for radical prostatectomy. The advent of active surveillance has changed the management of low-risk disease, and chemotherapy and hormonal therapy have improved the outcomes of patients with distant disease. Ongoing research and clinical trials are expected to yield more practice-changing results in the near future.

Influence of African American race on the association between preoperative biopsy grade group and adverse histopathologic features of radical prostatectomy

BACKGROUND

The current study was performed to evaluate the influence of race on the association between biopsy grade group (GrGp) and the risk of detectable prostate-specific antigen (PSA) and adverse histopathological outcomes after radical prostatectomy (RP).

METHODS

Data regarding 4073 men (1344 African American men; 33%) who were treated with RP were categorized based on the 5-tiered GrGp system. Logistic regression was used to test the association between biopsy GrGp and PSA nadir (<0.1 ng/mL) after RP as well as adverse pathological features among all patients and stratified by race.

RESULTS

Those patients with a higher biopsy GrGp were found to have lower odds of achieving a PSA nadir <0.1 ng/mL after RP on unadjusted and multivariable analysis (both P < .001). On unadjusted and multivariable analysis, higher GrGp was associated with increased odds of each of the adverse pathological features, namely, GrGp ≥3, extraprostatic extension, seminal vesicle invasion, positive surgical resection margin, and positive lymph nodes (all P < .001). Race had no significant interaction with biopsy GrGp in the prediction of PSA nadir after RP (P = .91) or any adverse pathological features (all P > .06) except positive lymph nodes. When the models were stratified by race, the associations between preoperative biopsy GrGp and having a PSA nadir <0.1 ng/mL, high-grade final pathology, or other adverse histopathologic features were similar in both races except as noted for positive lymph nodes.

CONCLUSIONS

Higher preoperative biopsy GrGp is associated with increased odds of adverse histopathological findings as well as lower odds of a PSA nadir <0.1 ng/mL after RP. These associations are largely independent of race, suggesting that GrGp is an accurate tool for risk stratification in both black and white men.

Predictive Factors and Oncologic Outcome of Downgrade to Pathologic Gleason Score 6⁻7 after Radical Prostatectomy in Patients with Biopsy Gleason Score 8⁻10

Gleason score (GS) 8⁻10 is associated with adverse outcomes in prostate cancer (PCa). However, biopsy GS (bGS) may be upgraded or downgraded post-radical prostatectomy (RP). We aimed to investigate predictive factors and oncologic outcomes of downgrade to pathologic GS (pGS) 6⁻7 after RP in PCa patients with bGSs 8⁻10. We retrospectively reviewed clinical data of patients with bGS ≥ 8 undergoing RP. pGS downgrade was defined as a pGS ≤ 7 from bGS ≥ 8 post-RP. Univariate and multivariate cox regression analysis, logistic regression analysis, and Kaplan⁻Meier curves were used to analyze pGS downgrade and biochemical recurrence (BCR). Of 860 patients, 623 and 237 had bGS 8 and bGS ≥ 9, respectively. Post-RP, 332 patients were downgraded to pGS ≤ 7; of these, 284 and 48 had bGS 8 and bGS ≥ 9, respectively. Prostate-specific antigen (PSA) levels; clinical stage; and adverse pathologic features such as extracapsular extension, seminal vesicle invasion and positive surgical margin were significantly different between patients with pGS ≤ 7 and pGS ≥ 8. Furthermore, bGS 8 (odds ratio (OR): 0.349, p < 0.001), PSA level < 10 ng/mL (OR: 0.634, p = 0.004), and ≤cT3a (OR: 0.400, p < 0.001) were identified as significant predictors of pGS downgrade. pGS downgrade was a significant positive predictor of BCR following RP in patients with high bGS (vs. pGS 8, hazard radio (HR): 1.699, p < 0.001; vs. pGS ≥ 9, HR: 1.765, p < 0.001). In addition, the 5-year BCR-free survival rate in patients with pGS downgrade significantly differed from that in patients with bGS 8 and ≥ 9 (52.9% vs. 40.7%, p < 0.001). Among patients with bGS ≥ 8, those with bGS 8, PSA level < 10 ng/mL, and ≤cT3a may achieve pGS downgrade after RP. These patients may have fewer adverse pathologic features and show a favorable prognosis; thus we suggest that active treatment is needed in these patients. In addition, patients with high-grade bGS should be managed aggressively, even if they show pGS downgrade.

Prostatic Adenocarcinoma: A Grading from Gleason to the New Grade-Group System: A Historical and Critical Review

The introduction of the Gleason grading system revolutionised prognostic parameters and determination of patient treatment regiments for prostatic adenocarcinomas, and has become synonymous with prostate cancer, almost universally applied in clinical settings to predict radical prostatectomy specimen findings, potential biochemical failure, local recurrences, lymph nodes or distant metastases in patients not receiving any treatment as well as those receiving treatment including radiation therapy, surgical treatment such as radical prostatectomy and other therapies etc,. However, characterisation and classification of prostate cancer is very different compared to 40-50 years ago when Gleason scores were first introduced. Despite this radical shift in classification, the Gleason system has remained one of the most important prognostic factors in prostate cancer, only possible as a result of timely and appropriate modifications to this characterisation system made in 2005 and 2014. However, even after these modifications, certain limitations of the Gleason system remain, due to which a new prostate cancer prognostic grade group system was introduced in 2014, which was widely accepted in the 2014 ISUP consensus conference, and incorporated into the WHO classification of thetumor of the Urinary System and Male Genital Tract in 2016. Herein, this article will discuss how this new prognostic grade group system, which is regarded as simpler and more accurate than the Gleason system risk stratification groups, will be used in conjunction with the Gleason system to improve patient prognosis and treatment.

Prognostic significance of the presence of tertiary Gleason grade 5 in robot-assisted radical prostatectomy specimens in Japanese patients with clinically localized prostate cancer

BACKGROUND

The aim of this study was to study the prognostic significance of tertiary Gleason grade (TGG) 5 in patients with clinically localized prostate cancer treated with robot-assisted radical prostatectomy (RARP).

METHODS

A total of 600 Japanese patients who underwent RARP for clinical stage T1-3N0M0 prostate cancer were evaluated. TGG5 was evaluated according to the International Society of Urological Pathology criterion. Cox hazard regression was used to evaluate the prognostic significance of prostate-specific antigen and pathological features in RARP specimens.

RESULTS

Of the 600 RARP specimens, 92 (15%) had TGG5. TGG5 component was found in 30 (10%) of 287 cases with Gleason score (GS) 3 + 4, 55 (37%) of 149 cases with GS 4 + 3 and 7 (17%) of 40 cases with GS 4 + 4. There were no significant differences in pathological stage and surgical margin status between GS 3 + 4 with and without TGG5, as well as between GS 4 + 4 with and without TGG5. Of the 600 patients, 92 (15%) patients had biochemical recurrence (BCR) after surgery, with a median follow-up period of 42 (3-104) months. There were no differences in 5-year BCR-free survival rates between patients with GS 3 + 4 with and without TGG5 (92 vs. 100%, P = 0.16), as well as between patients with GS 4 + 3 with and without TGG5 (79 vs. 71%, P = 0.30). Similarly, there were no differences in 3-year BCRFS rates between patients with GS 4 + 4 with and without TGG5 (80 vs. 71%, P = 0.38).

CONCLUSIONS

In our population, the presence of TGG5 in RARP specimens had no strong impact on pathological and prognostic outcomes.

Spectrum of Cribriform Proliferations of the Prostate: From Benign to Malignant

Context.—

The presence of cribriform glands/ducts in the prostate can pose a diagnostic challenge. Cribriform glands/ducts include a spectrum of lesions, from benign to malignant, with vastly different clinical, prognostic, and treatment implications.

Objective.—

To highlight the diagnostic features of several entities with a common theme of cribriform architecture. We emphasize the importance of distinguishing among benign entities such as cribriform changes and premalignant to malignant entities such as high-grade prostatic intraepithelial neoplasia, atypical intraductal cribriform proliferation, intraductal carcinoma of the prostate, and invasive adenocarcinoma (acinar and ductal types). The diagnostic criteria, differential diagnosis, and clinical implications of these cribriform lesions are discussed.

Data Sources.—

Literature review of pertinent publications in PubMed up to calendar year 2017. Photomicrographs obtained from cases at the University of California at Irvine and authors' collections.

Conclusions.—

Although relatively uncommon compared with small acinar lesions (microacinar carcinoma and small gland carcinoma mimickers), large cribriform lesions are increasingly recognized and have become clinically and pathologically important. The spectrum of cribriform lesions includes benign, premalignant, and malignant lesions, and differentiating them can often be subtle and difficult. Intraductal carcinoma of the prostate in particular is independently associated with worse prognosis, and its presence in isolation should prompt definitive treatment. Patients with atypical intraductal cribriform proliferation, intraductal carcinoma of the prostate, or even focal cribriform pattern of invasive adenocarcinoma in biopsies would not be ideal candidates for active surveillance because of the high risk of adverse pathologic findings associated with these entities.

Accuracy of standardized 12-core template biopsies versus non-standardized biopsies for detection of Epstein Grade 5 prostate cancer regarding the histology of the prostatectomy specimen

OBJECTIVE

To evaluate the effectiveness of EAU Guideline compliant transrectal ultrasound-guided 12-core prostate biopsies for detection of highly aggressive Epstein Grade 5 (Gleason Score 9-10) prostate cancer.

METHODS

Two hundred ninety-nine patients, treated by radical prostatectomy for prostate cancer, have been prospectively recorded in a database and were evaluated for this study. Pre-operatively, all patients received transrectal ultrasound-guided biopsies according to inhomogeneous templates chosen by the referring urologist. We evaluated the outcomes according to a stratified group-analysis: Group 1 received less than 12 biopsies, Group 2 received more than 12 biopsies, and Group 3 received exactly 12 biopsies, according to the EAU Guidelines template. After surgical removal of the prostate, 12 EAU Guideline-templated biopsies were performed in all prostatectomy specimens, directly after the surgery. Pre-operative and post-operative Epstein Grade 5 biopsy detection rates were thereafter correlated with these prostatectomy specimens.

RESULTS

In prostatectomy specimens, the histology of 12 patients (4.0%) were Epstein Grade 1, 31 patients (10.5%) were Epstein Grade 2, 190 patients (63.5%) were Epstein Grade 3, 27 patients (9%) were Epstein Grade 4, and 39 patients (13%) were Epstein Grade 5. The detection rate of Epstein Grade 5 compared to the radical prostatectomy specimen was: Group 1: 23.0% pre-operatively and 61.5% post-operatively, Group 2: 33.3% pre-operatively and 58.3% post-operatively; and Group 3: 57.1% pre-operatively and 64.2% post-operatively.

CONCLUSION

Detection rates of highly aggressive Epstein Grade 5 prostate cancer vary considerably according to the biopsy technique. EAU Guideline compliant 12-core template biopsies increase the detection rates of Epstein Grade 5 prostate cancer.

Contemporary Gleason grading and novel Grade Groups in clinical practice

PURPOSE OF REVIEW

The Gleason grading system provides important information for guiding prostate cancer patients' management and prognostication. The grading system underwent significant modifications over the past decade. In 2005 and more recently in 2014, the International Society of Urological Pathology (ISUP) held two consensus conferences to update prostate cancer grading. Recently, five prognostic grade groups have been proposed to be used in parallel to the Gleason grading system. The purpose of this review is to highlight the key changes in the Gleason grading system and the utility of the grade groups to better reflect biologic behavior for both patients and clinicians.

RECENT FINDINGS

At the 2014 ISUP consensus conference, prostate cancer Gleason grading was updated and a previously proposed concept of five prognostic grade groups, from 1 to 5 was supported. The Grade Groups, used in parallel to the modified Gleason grading system, translate Gleason scores in five distinct risk categories where Grade Group 1 is defined as Gleason score 6 or less, Grade Group 2 as Gleason score 3 + 4 = 7, Grade Group 3 as Gleason score 4 + 3 = 7, Grade Group 4 as Gleason score 4 + 4 = 8, and Grade Group 5 as Gleason score 9/10. This 5-tiered grade group system better reflects biologic behavior and guides clinical care. The Grade Groups have been endorsed by the ISUP and the World Health Organization. The performance of the Grade Groups has been examined in several recent studies.

SUMMARY

This review summarizes developments over the last year in the use of grade groups and outlines their value in clinical practice.

Prostatectomy-based validation of combined urine and plasma test for predicting high grade prostate cancer

BACKGROUND

Distinguishing between low- and high-grade prostate cancers (PCa) is important, but biopsy may underestimate the actual grade of cancer. We have previously shown that urine/plasma-based prostate-specific biomarkers can predict high grade PCa. Our objective was to determine the accuracy of a test using cell-free RNA levels of biomarkers in predicting prostatectomy results.

METHODS

This multicenter community-based prospective study was conducted using urine/blood samples collected from 306 patients. All recruited patients were treatment-naïve, without metastases, and had been biopsied, designated a Gleason Score (GS) based on biopsy, and assigned to prostatectomy prior to participation in the study. The primary outcome measure was the urine/plasma test accuracy in predicting high grade PCa on prostatectomy compared with biopsy findings. Sensitivity and specificity were calculated using standard formulas, while comparisons between groups were performed using the Wilcoxon Rank Sum, Kruskal-Wallis, Chi-Square, and Fisher's exact test.

RESULTS

GS as assigned by standard 10-12 core biopsies was 3 + 3 in 90 (29.4%), 3 + 4 in 122 (39.8%), 4 + 3 in 50 (16.3%), and > 4 + 3 in 44 (14.4%) patients. The urine/plasma assay confirmed a previous validation and was highly accurate in predicting the presence of high-grade PCa (Gleason ≥3 + 4) with sensitivity between 88% and 95% as verified by prostatectomy findings. GS was upgraded after prostatectomy in 27% of patients and downgraded in 12% of patients.

CONCLUSIONS

This plasma/urine biomarker test accurately predicts high grade cancer as determined by prostatectomy with a sensitivity at 92-97%, while the sensitivity of core biopsies was 78%.

Validation of the WHO 2016 new Gleason score of prostatic carcinoma

Context

New Gleason Score of Prostate.

Aims

The aim of this study is to assign the patients with carcinoma prostate into new prognostic grade groups (PGGs) based on revised Gleason score (GS) and follow-up according to the WHO 2016.

Subjects and Methods

All the biopsies/resected specimens of carcinoma prostate from January 2014 to June 2016 were reviewed, and GS was done according to the WHO 2016. Accordingly, cribriform, fused, and glomeruloid glands were assigned GS 4. Thus, two groups were identified with GS 7 (3 + 4 and 4 + 3). The patients were grouped into PGGs 1-5. The number of patients with change in the prognostic group along with follow-up was calculated.

Results

There were 143 patients with carcinoma prostate, with a median age of 65 years. The initial GS was revised, and there was a decrease in GS 3 + 4 from 13.9% to 9% and increase in 4 + 3 from 19.6% to 23.8%. There was upgradation of PGG in 11 (7.69%) biopsies; with PGG from 1 to 2 in one; 2to 3 in eight; and 3to 4 in two. Follow-up at 2 years in 22 showed the poor prognoses in the patients who were upgraded to the higher prognostic group.

Conclusions

A change in PGG according to the WHO 2016 criteria was assigned in 7.69% biopsies of carcinoma prostate, and it correlated with prognosis.

Impact of five-tiered Gleason grade groups on prognostic prediction in clinical stage T3 prostate cancer undergoing high-dose-rate brachytherapy

BACKGROUND

We evaluated a five-tiered Gleason grade groups arising from the 2014 International Society of Urological Pathology consensus conference on prognostic prediction in clinical stage T3a (extracapsular invasion) and T3b (seminal vesicle involvement) prostate cancer undergoing high-dose-rate brachytherapy (HDR-BT).

METHODS

From November 2003 to December 2012, 283 patients with stage T3 prostate cancer received HDR-BT and external beam radiation therapy (EBRT) with long-term androgen deprivation therapy (ADT). Of these, 203 (72%) and 80 (28%) patients had stage T3a and T3b disease, respectively. The mean dose to 90% of the planning target volume was 7.5 Gy/fraction of HDR-BT. After five fractions, EBRT with 10 fractions of 3 Gy was administered. All patients first underwent ≥6 months of neoadjuvant ADT, and adjuvant ADT continued for 36 months. Median follow-up was 74 months from the start of radiotherapy.

RESULTS

The 10-year biochemical recurrence (BCR) -free rate for stage T3a and T3b disease was 79% and 64%, respectively (P = 0.0083). The 10-year cancer-specific survival (CSS) rate for stage T3a and T3b was 96% and 91%, respectively (P = 0.0305). Although grade groups ≥4 were independent predictors for BCR in cT3a patients (P = 0.0270), they failed to significantly predict prostate cancer-specific mortality (PCSM) among cT3a patients. Among cT3b patients, grade group 5 was a significant predictor of both BCR (P = 0.0017) and PCSM (P = 0.0233). Among stage T3a patients, no significant difference existed in 10-year CSS between grade groups 5 and 4 (94% vs 97%, P = 0.3960). In contrast, grade group 5 had a significantly worse outcome in 10-year CSS than grade group 4 among stage T3b patients (74% vs 100%, P = 0.0350).

CONCLUSIONS

Stage T3a patients with grade groups 4/5 and stage T3b with grade group 4 had fairly low PCSM risk. Approximately one of four patients among stage T3b patients with grade group 5 showed PCSM after combined HDR-BT and EBRT with long-term ADT. Stage T3b patients with grade group 5 may have a greater risk for PCSM.

Oncological outcomes in an Australian cohort according to the new prostate cancer grading groupings

Background

A new 5-tiered grading grouping system has recently been endorsed for reporting of prostate cancer (PCa) grade to better reflect escalating risk of progression and cancer death. While several validations of the new grade groupings have been undertaken, most have involved centralised pathological review by specialist urological pathologists.

Methods

Participants included 4268 men with non-metastatic PCa diagnosed between 2006 and 2013 from the multi-institutional South Australia Prostate Cancer Clinical Outcomes Collaborative registry. PCa-specific survival and biochemical recurrence-free survival were compared across the five grade groups using multivariable competing risk regression.

Results

For the entire cohort, risk of PCa death increased with increasing grade groups (at biopsy) Adjusted subdistribution-hazard ratios [sHR] and 95% confidence intervals [95%CI] were: 2.2 (1.5–3.6); 2.5 (1.6–4.2); 4.1 (2.6–6.7) and 8.7 (4.5–14.0) for grade groups II (pattern 3 + 4), III (pattern 4 + 3), IV (total score 8) and V (total score 9–10) respectively, relative to grade group I (total score < =6). Clear gradients in risk of PCa death were observed for radical prostatectomy (RP), but were less clear for those who had radiotherapy (RT) with curative intent and those who were managed conservatively. Likewise, risk of biochemical recurrence increased across grade groups, with a strong and clear gradient for men undergoing RP [sHR (95%CI): 2.0 (1.4–2.8); 3.8 (2.9–5.9); 5.3 (3.5–8.0); 11.2 (6.5–19.2) for grade groups II, III, IV and V respectively, relative to grade group I], and a less clear gradient for men undergoing RT.

Conclusion

In general, the new five-tiered grade groupings distinguished PCa survival and recurrence outcomes for men with PCa. The absence of a clear gradient for RT may be due to heterogeneity in this patient group.

Contemporary grading of prostate cancer: 2017 update for pathologists and clinicians

The Gleason grading system for prostate cancer (PCa) was developed in the 1960s by DF Gleason. Due to changes in PCa detection and treatment, the application of the Gleason grading system has changed considerably in pathology routine practice. Two consensus conferences were held in 2005 and in 2014 to update PCa Gleason grading. This review provides a summary of the changes in the grading of PCa from the original Gleason grading system to the prognostic grade grouping, as well as a discussion of the clinical significance of the percentage of Gleason patterns 4 and 5.

SOCS3 Immunohistochemical Expression Seems to Support the 2005 and 2014 International Society of Urological Pathology (ISUP) Modified Gleason Grading System

BACKGROUND

In the 2014, The International Society of Urological Pathology (ISUP) consensus conference update the grading of prostate, last revised in 2005. In this study we evaluate the SOCS3 immunohistochemical protein expression in different Gleason prostatic adenocarcinoma: classical Gleason grade 3, classical Gleason grade 3 upgraded to Gleason grade 4 according to the ISUP modifications and classical and modified Gleason grade 4. The major conclusions were: (i) Cribriform glands should be assigned a Gleason pattern 4, regardless of morphology; (ii) Glomeruloid glands should be assigned a Gleason pattern 4, regardless of morphology; (iii) Grading of mucinous carcinoma of the prostate should be based on its underlying growth pattern rather than all as pattern 4; and (iv) Intraductal carcinoma of the prostate without invasive carcinoma should not assigned Gleason grade and a comment about aggressive carcinoma probably associated should be made. In a recent report we analyzed the methylathion status of cytokine signaling (SOCS) proteins 3 (SOCS3) gene and the consequences of promoter hypermethylation on mRNA and protein expression in a collection of prostate cancer and benign prostate hyperplasia (BPH) and for the first time we demonstrated that a hypermethylation of SOCS3 with a significant reduction of its mRNA and protein expression identifies a subgroup of prostate cancer with a more aggressive behavior. Moreover we demonstrated that the immunohystochemical analysis of SOCS3 protein expression in prostatic cancer biopsies may provide a useful and easier method than SOCS3 methylation analysis to individuate in cancer with intermediate-high grade Gleason score a subgroup of prostate cancer with a more aggressive behavior.

METHODS

A total of 148 radical prostatectomy with diagnosis of prostatic acinar adenocarcinoma were stratified into three different categories on the basis of Gleason grade: (i) Twenty-six prostatic adenocarcinoma with classical and modified Gleason grade 3; (ii) Fifty seven prostatic adenocarcinoma with classical Gleason grade 3 upgraded to Gleason grade 4 by 2005 and 2014 ISUP Consensus Conference; and (iii) Sixty five prostatic adenocarcinoma with classical and modified Gleason grade 4. Immunohistochemical analysis for SOCS3 was performed and SOCS3 staining intensity were evaluated by two pathologists in three different ways on the basis of the intensity of cytoplasmatic staining: positive (intense cytoplasmatic staining in more than 50% of neoplastic cells) (+), negative (absence of cytoplasmatic staining in more than 50% of neoplastic cells) (-), weakly positive (weak cytoplasmatic staining in more than 50% of neoplastic cells (+/-).

RESULTS

In the group of prostatic adenocarcinoma Gleason grade 3 we found that SOCS3 positivity (+) were observed in 19 out of 26 cases (73.1%); in 5 out of 26 prostatic adenocarcinoma the neoplastic glands showed weak intensity SOCS3 staining (+/-) (19.2%), while in only two cases we found SOCS-3 negativity (-) (7.7%); in the group of cases with prostatic adenocarcinoma with Gleason grade 4, 16 out 65 cases (24.6%) showed SOCS3 positivity (+); 18 out 65 cases (27.7%) SOCS3 weakly positive (+/-), and in 31 cases (47.7%) SOCS3 negative staining (-) were observed. Interestingly, the group of prostatic adenocarcinoma with histological Gleason 3 pattern upgraded to Gleason 4 pattern according to the 2005 and 2014 ISUP modified grading system, showed SOCS3 positivity (+) in 16 out of 57 cases (28%), in 16 out 57 cases (28%) a weakly positive for SOCS3 (+/-) were observed, while 25 cases (44%) showed negative SOCS3 staining (-).

CONCLUSIONS

In this study we demonstrated a significant association of SOCS3 positivity (+) with prostatic carcinoma classical Gleason pattern 3 (P < 0.0001), while SOCS3 negative pattern (-) or SOCS3 weakly positive pattern (+/-) were associated to prostatic carcinomas with Gleason pattern 3 upgraded to Gleason pattern 4 (P = 0.0002) and with classical Gleason pattern 4. The significant difference of SOCS3 immunohistochemical expression between classical Gleason grade 3 and Gleason grade 4 upgraded to grade 4 seems to support the definitions and the modifications of Gleason grade 4 of the 2005 and the 2014 International Society of Urological Pathology (ISUP). The hypoexpression of SOCS3 protein in glomeruloid glands could support the hypothesis that from molecular point of view this growth pattern could be different from classical Gleason pattern 3 and biologically more closely to Gleason pattern 4, confirming the conclusions of the 2014 ISUP Conference assigning a Gleason pattern 4 to glomeruloid glands regardless of morphology. Prostate 77: 597-603, 2017. © 2017 Wiley Periodicals, Inc.

Prostate cancer: from Gleason scoring to prognostic grade grouping

The Gleason grading system was developed in the late 1960s by Dr. Donald F. Gleason. Due to changes in prostatic adenocarcinoma (PAC) detection and treatment, newer technologies to better characterize prostatic pathology, subsequently described variants of PAC and further data relating various morphologic patterns to prognosis, the application of the Gleason grading system changed substantially in surgical pathology. First in 2005 and more recently in 2014, consensus conferences were held to update PAC grading. Here, we review of the successive changes in the grading of PAC from the original system, with emphasis on the newest prognostic grade grouping.

Application of a Prognostic Gleason Grade Grouping System to Assess Distant Prostate Cancer Outcomes

BACKGROUND

There is growing enthusiasm for the adoption of a novel grade grouping system to better represent Gleason scores.

OBJECTIVE

To evaluate the ability of prognostic Gleason grade groups to predict prostate cancer (PCa)-specific mortality (PCSM) and bone metastatic progression.

DESIGN, SETTING, AND PARTICIPANTS

We identified patients with PCa enrolled in the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE) registry across treatment strategies, including conservative and nondefinitive therapy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We examined the prognostic ability of Gleason grade groups to predict risk of PCSM and bone metastasis using the Kaplan-Meier method and unadjusted and adjusted Cox proportional hazards models.

RESULTS AND LIMITATIONS

We identified 10529 men with PCa followed for a median of 81 mo (interquartile range 40-127), including 64% in group I (< 3 + 4); 17% in group II (3+4); 9% in group III (4+3); 6% in group IV (4+4); and 4% in group V (≥ 4 + 5). Relative to grade group I, the unadjusted risks of PCSM and bone metastasis were significantly associated with prognostic grade groupings for both biopsy and prostatectomy samples (all p<0.01). Pairwise comparisons within Gleason sums collapsed within grade group V were not significant; however, this analysis was limited by a small representation of men with Gleason pattern ≥ 4 + 5.

CONCLUSIONS

The prognostic grade grouping system is associated with risk of PCSM and metastasis across management strategies, including definitive therapy, conservative management, and primary androgen deprivation.

PATIENT SUMMARY

A five-level reporting system for prostate cancer pathology is associated with the risk of late prostate cancer endpoints.

New Prostate Cancer Grading System Predicts Long-term Survival Following Surgery for Gleason Score 8-10 Prostate Cancer

BACKGROUND

The newly proposed five-tiered prostate cancer grading system (PCGS) divides Gleason score (GS) 8-10 disease into GS 8 and GS 9-10 on the basis of biochemical recurrence (BCR) following radical prostatectomy (RP) as an outcome. However, BCR does not necessarily portend worse survival outcomes.

OBJECTIVE

To assess the significance of distinguishing GS 8 versus 9-10 disease in terms of long-term survival outcomes for both the preoperative setting using biopsy (Bx) GS and the postoperative setting with RP GS.

DESIGN, SETTING, AND PARTICIPANTS

Of 23918 men who underwent RP between 1984 and 2014, there were 721 men with biopsy GS 8-10, and 1047 men with RP GS 8-10.

OUTCOME MEASURES AND STATISTICAL ANALYSIS

Clinicopathologic characteristics were compared between men with GS 8 and those with GS 9-10. We compared all-cause mortality (ACM) and prostate cancer-specific mortality (PCSM) risk between the groups using Cox regression and competing-risks analyses, adjusting for other perioperative variables and death from other causes as the competing event.

RESULTS AND LIMITATIONS

Compared to men with GS 8, men with GS 9-10 had later RP year and higher pathologic stage. Among men with Bx GS 8-10, 115 died (82 due to PC) with median follow-up of 3 yr (interquartile range [IQR] 1-7) for both overall and cancer-specific survival. Of men with RP GS 8-10, 221 died (151 due to PC) with median follow-up of 4 yr (IQR 2-8) and 4 yr (IQR 2-9) for overall and cancer-specific survival, respectively. PC-specific survival rates were significantly lower for men with GS 9-10 compared to men with GS 8 for both Bx (hazard ratio [HR] 2.13, 95% confidence interval [CI] 1.37-3.30; p<0.01) and RP GS (HR 2.38, 95% CI 1.74-3.28; p<0.01). This association persisted in multivariable models after adjusting for perioperative variables.

CONCLUSIONS

Men with GS 9-10 had higher ACM and PCSM rates compared to those with GS 8. GS 8 and GS 9-10 PC should be considered separately in both the preoperative and postoperative setting as suggested by the new PCGS.

PATIENT SUMMARY

The prostate cancer grading system can predict mortality risk after radical prostatectomy (RP) for men with Gleason score 8-10 disease based on both biopsy and RP Gleason scores. There are significant differences in all-cause mortality and prostate cancer-specific mortality following surgery between men with Gleason score 8 and those with Gleason score 9-10 disease.

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.

One is the new six: The International Society of Urological Pathology (ISUP) patient-focused approach to Gleason grading

N/A

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.

Validation of International Society of Urological Pathology (ISUP) grading for prostatic adenocarcinoma in thin core biopsies using TROG 03.04 'RADAR' trial clinical data

In 2014 a consensus conference convened by the International Society of Urological Pathology (ISUP) adopted amendments to the criteria for Gleason grading and scoring (GS) for prostatic adenocarcinoma. The meeting defined a modified grading system based on 5 grading categories (grade 1, GS 3+3; grade 2, GS 3+4; grade 3, GS 4+3; grade 4, GS 8; grade 5, GS 9-10). In this study we have evaluated the prognostic significance of ISUP grading in 496 patients enrolled in the TROG 03.04 RADAR Trial. There were 19 grade 1, 118 grade 2, 193 grade 3, 88 grade 4 and 79 grade 5 tumours in the series, with follow-up for a minimum of 6.5 years. On follow-up 76 patients experienced distant progression of disease, 171 prostate specific antigen (PSA) progression and 39 prostate cancer deaths. In contrast to the 2005 modified Gleason system (MGS), the hazards of the distant and PSA progression endpoints, relative to grade 2, were significantly greater for grades 3, 4 and 5 of the 2014 ISUP grading scheme. Comparison of predictive ability utilising Harrell's concordance index, showed 2014 ISUP grading to significantly out-perform 2005 MGS grading for each of the three clinical endpoints.

From Gleason to International Society of Urological Pathology (ISUP) grading of prostate cancer

Gleason grading of prostate cancer has gained worldwide acceptance since its introduction 50 years ago. This system has fulfilled the role of a powerful prognostic indicator for many years and this has influenced treatment. There have been numerous changes to the management and diagnosis of prostate cancer since 1966, including prostate-specific antigen screening, resulting in the early detection of prostate cancer, This has resulted in the evolution of Gleason grading with the informal adoption of a number of alterations. Significant changes to Gleason grading were made in 2005 through a consensus conference convened by the International Society of Urological Pathology (ISUP). In more recent times, the necessity for further changes to prostate cancer grading has been apparent and a follow-up ISUP consensus conference was held in 2014. Changes resulting from this conference included the classifying of all cribriform cancer and glomeruloid patterns as Gleason grade 4, the grading of mucinous adenocarcinoma based on underlying architecture rather than uniformly considering these tumors as pattern 4, and the introduction of a Gleason score (GS)-based 5 grade system, which incorporated the 2014 modifications to the Gleason grading system. Designated ISUP grade, this system consists of five grades: grade 1 (GS ≤3 + 3), grade 2 (GS 3 + 4), grade 3 (GS 4 + 3), grade 4 (GS 4 + 4, 3 + 5, 5 + 3) and grade 5 (GS 9-10). With further advances recently reported in the literature, it is apparent that amendments to the current system are likely to be necessary in the future.

Gleason score and tumor laterality in radical prostatectomy and transrectal ultrasound-guided biopsy of the prostate: a comparative study

We aimed to compare Gleason score and tumor laterality between transrectal ultrasound-guided biopsy of the prostate (TRUSBX) and radical prostatectomy (RP). Some factors that could cause a discrepancy in results between these two procedures were also evaluated. Among the 318 cases reviewed, 191 cases were selected for inclusion in this comparative study. We divided the patients into two groups using the Gleason score: an intermediate/high-grade group (≥7) and a low-grade group (<6). Exploratory analyses were conducted for comparisons between groups. We also performed comparisons between TRUSBX and RP for tumor laterality. TRUSBX overestimated 6% and underestimated 24% cases in comparison with RP for Gleason score, and overestimated 2.6% and underestimated 46% cases compared with RP for tumor laterality. Biopsy specimens were slightly smaller in TRUSBX cases with underestimated tumor laterality (P < 0.05), and no relationship between the biopsy specimen size and underestimated Gleason score in TRUSBX was found. Prostatic volume showed no statistical correlation with the likelihood of under or overestimation (P > 0.05). Thus, our study showed that TRUSBX has a high likelihood of underestimating both the Gleason score and tumor laterality in prostate cancer (PCa). The size of the fragment appears to be an important factor influencing the likelihood of laterality underestimation and Gleason score overestimation via TRUSBX. Due to the high likelihood of underestimation of the Gleason score and tumor laterality by 12-core prostate biopsy, we conclude that this type of biopsy should not be used alone to guide therapy in PCa.

Grading of prostatic adenocarcinoma: current state and prognostic implications

Background

Despite significant changes in the clinical and histologic diagnosis of prostate cancer, the Gleason grading system remains one of the most powerful prognostic predictors in prostate cancer. The correct diagnosis and grading of prostate cancer is crucial for a patient’s prognosis and therapeutic options. However, this system has undergone significant revisions and continues to have deficiencies that can potentially impact patient care.

Main Body

We describe the current state of grading prostate cancer, focusing on the current guidelines for the Gleason grading system and recent changes from the 2014 International Society of Urological Pathology Consensus Conference on Gleason Grading of Prostatic Carcinoma. We also explore the limitations of the current Gleason grading system and present a validated alternative to the Gleason score. The new grading system initially described in 2013 in a study from Johns Hopkins Hospital and then validated in a multi-institutional study, includes five distinct Grade Groups based on the modified Gleason score groups. Grade Group 1 = Gleason score ≤6, Grade Group 2 = Gleason score 3 + 4 = 7, Grade Group 3 = Gleason score 4 + 3 = 7, Grade Group 4 = Gleason score 8, Grade Group 5 = Gleason scores 9 and 10.

Conclusion

As this new grading system is simpler and more accurately reflects prostate cancer biology, it is recommended by the World Health Organization (WHO) to be used in conjunction with Gleason grading.

Gleason and Fuhrman no longer make the grade

Grading is an important prognostic parameter for prostate adenocarcinoma and renal cell carcinoma (RCC); however, the most frequently used classifications fail to account for advances in our understanding of the diagnostic features, classification and/or behaviour of these tumours. In 2005 and 2014, the International Society of Urological Pathology (ISUP) proposed changes to Gleason scoring with the adoption of the ISUP grading for prostate cancer in 2014 (grade 1, score 3 + 3; grade 2, score 3 + 4; grade 3, score 4 + 3; grade 4, score 8; grade 5, score 9-10). Internationally the Fuhrman grading system is widely employed despite criticisms related to its application, validity, and reproducibility. In 2012, the ISUP established a grading system for RCC (grade 1, the nucleolus is not seen or is inconspicuous and basophilic at ×400 magnification; grade 2, nucleoli are eosinophilic and clearly visible at ×400 magnification; grade 3, nucleoli are clearly visible at ×100 magnification; grade 4, tumours show extreme pleomorphism or rhabdoid and/or sarcomatoid morphology). This grading has been validated for clear cell RCC and papillary RCC. It was further recommended that chromophobe RCC not be graded. For other morphotypes of RCC, ISUP grading has not been validated as a prognostic parameter, but can be used for descriptive purposes.

The evolving Gleason grading system

The Gleason grading system for prostate adenocarcinoma has evolved from its original scheme established in the 1960s-1970s, to a significantly modified system after two major consensus meetings conducted by the International Society of Urologic Pathology (ISUP) in 2005 and 2014, respectively. The Gleason grading system has been incorporated into the WHO classification of prostate cancer, the AJCC/UICC staging system, and the NCCN guidelines as one of the key factors in treatment decision. Both pathologists and clinicians need to fully understand the principles and practice of this grading system. We here briefly review the historical aspects of the original scheme and the recent developments of Gleason grading system, focusing on major changes over the years that resulted in the modern Gleason grading system, which has led to a new "Grade Group" system proposed by the 2014 ISUP consensus, and adopted by the 2016 WHO classification of tumours of the prostate.

Clinical Validation of the 2005 ISUP Gleason Grading System in a Cohort of Intermediate and High Risk Men Undergoing Radical Prostatectomy

In 2005, the International Society of Urological Pathology (ISUP) introduced several modifications to the original Gleason system that were intended to enhance the prognostic power of Gleason score (GS). The objective of this study was to clinically validate the 2005 ISUP Gleason grading system for its ability to detect metastasis. We queried our institutional RP database for men with NCCN clinically localized intermediate to high-risk disease undergoing radical prostatectomy (RP) between 1992 and 2010 with no additional treatment until the time of metastatic progression. A case-cohort design was utilized. A total of 333 available RP samples were re-reviewed and GS was reassigned per the 2005 ISUP Gleason system. Cumulative incidence of metastasis was 0%, 8.4%, 24.5% and 44.4% among specimens that were downgraded, unchanged, had one point GS increase and two point GS increase, respectively. The hazard ratio for metastasis raised in GS 8 and 9 compared to GS 7 from 2.77 and 5.91 to 3.49 and 9.31, respectively. The survival c-index of GS increased from 0.70 to 0.80 when samples were re-graded at 5 years post RP. The c-index of the reassigned GS was higher than the original GS (0.77 vs 0.64) for predicting PCSM at 10 years post RP. The regraded GS improved the prediction of metastasis and PCSM. This validates the updated Gleason grading system using an unambiguous clinical endpoint and highlights the need for reassignment of Gleason grading according to 2005 ISUP system when considering comparisons of novel biomarkers to clinicopathological variables in archival cohorts.

Outcomes of Gleason score 3 + 4 = 7 prostate cancer with minimal amounts (<6%) vs ≥6% of Gleason pattern 4 tissue in needle biopsy specimens

OBJECTIVE

The International Society of Urological Pathology Gleason grading system was modified in 2005. Since the modified system was introduced, many cancers that previously would have been categorized as Gleason score (GS) 6 are now categorized as GS 7 based on biopsy specimens that only contain minimal amounts (<6%) of Gleason pattern (GP) 4 tissue. However, the clinical significance of observing <6% of GP 4 tissue in biopsies of GS 7 prostate cancer has not been studied.

MATERIAL AND METHODS

This study was based on needle biopsy specimens that were categorized as GS 6 or GS 7 and were obtained from patients who underwent radical prostatectomy (RP) with available follow-up data. We assessed the quantity of GP 4 tissue in biopsy specimens of GS 7 prostate cancer. Further, we evaluated the correlation between the quantity of GP 4 tissue and disease progression after RP.

RESULTS

GP 4 comprising 26-49% of the specimen, GS 4+3 and percentage of total core tissue scored as positive were significant and independent predictors of prostate-specific antigen (PSA) failure after RP, as assessed using a multivariate Cox regression model that included the quantity of GP 4 in the prostate biopsy specimen, preoperative PSA, perineural invasion, clinical stage, number of positive cores, and percentage of core tissue scored as positive. Cases with GS 3+3 and cases in which the observed GP 4 area was <6% did not differ significantly in terms of biochemical PSA recurrence (BPR) status. In contrast, cases with 6-25% GP 4 tissue, 26-49% GP 4 tissue, and GS 4+3 showed more frequent BPR than cases with GS 3+3.

CONCLUSIONS

Our data suggest that the quantity of GP 4 tissue in GS 7 cancer has clinical significance. However, there is a need for larger studies of the clinical significance of biopsy specimens that include <6% GP 4 tissue. We should reconsider whether the amount of GP 4 should be included in standart pathology reports.

The Significance of Accurate Determination of Gleason Score for Therapeutic Options and Prognosis of Prostate Cancer

The Gleason score (GS) to date remains one of the most reliable prognostic predictors in prostate cancer (PCa). However, the majority of studies supporting its prognostic relevance were performed prior to its modification by the International Society of Urological Pathology (ISUP) in 2005. Furthermore, the combination of Gleason grading and nuclear/nucleolar subgrading (Helpap score) has been shown to essentially improve grading concordance between biopsy and radical prostatectomy (RP) specimens. This prompted us to investigate the modified GS and combigrading (Gleason/Helpap score) in association with clinicopathological features, biochemical recurrence (BCR), and survival. Core needle biopsies and corresponding RP specimens from 580 patients diagnosed with PCa between 2005 and 2010 were evaluated. According to the modified GS, the comparison between biopsy and RP samples resulted in an upgrading from GS 6 to GS 7a and GS 7b in 65% and 19%, respectively. Combigrading further resulted in an upgrading from low grade (GS 6/2a) to intermediate grade PCa (GS 6/2b) in 11.1% and from intermediate grade (GS 6/2b) to high grade PCa (GS 7b/2b) in 22.6%. Overall, well-differentiated PCa (GS 6/2a) was detected in 2.8% of RP specimens, while intermediate grade (GS 6/2b and GS 7a/2b) and high grade cancers (≥ GS 7b) accounted for 39.5% and 57.4% of cases, respectively. At a mean follow-up of 3.9 years, BCR was observed in 17.6% of patients with intermediate (9.8%) or high grade PCa (30.2%), while PSA relapse did not occur in GS 6/2a PCa. In conclusion, adding nuclear/nucleolar subgrading to the modified GS allowed for a more accurate distinction between low and intermediate grade PCa, therefore offering a valuable tool for the identification of patients eligible for active surveillance (AS).

Gleason Score 6 - Prostate Cancer or Benign Variant?

The leading motivation behind wanting to call a 'malignant' prostate lesion 'benign' is the evidence of indolent prostate cancer that is not associated with a fatal outcome and in part makes therapeutic measures such as surgery and radiotherapy appear like overtreatment for some or possibly the majority of such patients. The present article reviews the definitions of 'precancerous lesion' and 'cancer' from a histopathologic point of view as the basis and gold standard for diagnosis. It is clear that with the 2 modifications implemented since its first publication, the Gleason score as the grading system for prostate cancer has shifted towards a low malignant subgroup diagnosed as Gleason 6. The recommendation of the International Society of Urological Pathology to change the Gleason score to a 5-tiered system, starting with grade group 1, is presented here, and may help doctor-patient communication especially in the active surveillance setting.

[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.

Gleason 6 Prostate Cancer: Translating Biology into Population Health

PURPOSE

Gleason 6 (3+3) is the most commonly diagnosed prostate cancer among men with prostate specific antigen screening, the most histologically well differentiated and is associated with the most favorable prognosis. Despite its prevalence, considerable debate exists regarding the genetic features, clinical significance, natural history, metastatic potential and optimal management.

MATERIALS AND METHODS

Members of the Young Urologic Oncologists in the Society of Urologic Oncology cooperated in a comprehensive search of the peer reviewed English medical literature on Gleason 6 prostate cancer, specifically focusing on the history of the Gleason scoring system, histological features, clinical characteristics, practice patterns and outcomes.

RESULTS

The Gleason scoring system was devised in the early 1960s, widely adopted by 1987 and revised in 2005 with a more restrictive definition of Gleason 6 disease. There is near consensus that Gleason 6 meets pathological definitions of cancer, but controversy about whether it meets commonly accepted molecular and genetic criteria of cancer. Multiple clinical series suggest that the metastatic potential of contemporary Gleason 6 disease is negligible but not zero. Population based studies in the U.S. suggest that more than 90% of men newly diagnosed with prostate cancer undergo treatment and are exposed to the risk of morbidity for a cancer unlikely to cause symptoms or decrease life expectancy. Efforts have been proposed to minimize the number of men diagnosed with or treated for Gleason 6 prostate cancer. These include modifications to prostate specific antigen based screening strategies such as targeting high risk populations, decreasing the frequency of screening, recommending screening cessation, incorporating remaining life expectancy estimates, using shared decision making and novel biomarkers, and eliminating prostate specific antigen screening entirely. Large nonrandomized and randomized studies have shown that active surveillance is an effective management strategy for men with Gleason 6 disease. Active surveillance dramatically reduces the number of men undergoing treatment without apparent compromise of cancer related outcomes.

CONCLUSIONS

The definition and clinical relevance of Gleason 6 prostate cancer have changed substantially since its introduction nearly 50 years ago. A high proportion of screen detected cancers are Gleason 6 and the metastatic potential is negligible. Dramatically reducing the diagnosis and treatment of Gleason 6 disease is likely to have a favorable impact on the net benefit of prostate cancer screening.

The prostate cancer susceptibility variant rs2735839 near KLK3 gene is associated with aggressive prostate cancer and can stratify gleason score 7 patients

PURPOSE

Gleason score (GS) 7 prostate cancer is a heterogeneous disease with different clinical behavior. We sought to identify genetic biomarkers that may predict the aggressiveness of GS 7 diseases.

EXPERIMENTAL DESIGN

We genotyped 72 prostate cancer susceptibility SNPs identified in genome-wide association studies in 1,827 white men with histologically confirmed prostate adenocarcinoma. SNPs associated with disease aggressiveness were identified by comparing high-aggressive (GS ≥8) and low-aggressive (GS ≤6) cases. The significant SNPs were then tested to see whether they could further stratify GS 7 prostate cancer.

RESULTS

Three SNPs-rs2735839, rs10486567, and rs103294-were associated with biopsy-proven high-aggressive (GS ≥8) prostate cancer (P < 0.05). Furthermore, the frequency of the variant allele (A) at rs2735839 was significantly higher in patients with biopsy-proven GS 4+3 disease than in those with GS 3 + 4 disease (P = 0.003). In multivariate logistic regression analysis, patients carrying the A allele at rs2735839 exhibited a 1.85-fold (95% confidence interval, 1.31-2.61) increased risk of being GS 4 + 3 compared with those with GS 3 + 4. The rs2735839 is located 600 base pair downstream of the KLK3 gene (encoding PSA) on 19q13.33 and has been shown to modulate PSA level, providing strong biologic plausibility for its association with prostate cancer aggressiveness.

CONCLUSIONS

We confirmed the association of the rs2735839 with high-aggressive prostate cancer (GS ≥8). Moreover, we reported for the first time that rs2735839 can stratify GS 7 patients, which would be clinically important for more accurately assessing the clinical behavior of the intermediate-grade prostate cancer and for tailoring personalized treatment and posttreatment management.