Gleason score 7 adenocarcinoma of the prostate with lymph node metastases: analysis of 184 radical prostatectomy specimens

Nomogram Models for Distinguishing Intraductal Carcinoma of the Prostate From Prostatic Acinar Adenocarcinoma Based on Multiparametric Magnetic Resonance Imaging

OBJECTIVE

To compare multiparametric magnetic resonance imaging (MRI) features of intraductal carcinoma of the prostate (IDC-P) with those of prostatic acinar adenocarcinoma (PAC) and develop prediction models to distinguish IDC-P from PAC and IDC-P with a high proportion (IDC ≥ 10%, hpIDC-P) from IDC-P with a low proportion (IDC < 10%, lpIDC-P) and PAC.

MATERIALS AND METHODS

One hundred and six patients with hpIDC-P, 105 with lpIDC-P and 168 with PAC, who underwent pretreatment multiparametric MRI between January 2015 and December 2020 were included in this study. Imaging parameters, including invasiveness and metastasis, were evaluated and compared between the PAC and IDC-P groups as well as between the hpIDC-P and lpIDC-P subgroups. Nomograms for distinguishing IDC-P from PAC, and hpIDC-P from lpIDC-P and PAC, were made using multivariable logistic regression analysis. The discrimination performance of the models was assessed using the receiver operating characteristic area under the curve (ROC-AUC) in the sample, where the models were derived from without an independent validation sample.

RESULTS

The tumor diameter was larger and invasive and metastatic features were more common in the IDC-P than in the PAC group (P < 0.001). The distribution of extraprostatic extension (EPE) and pelvic lymphadenopathy was even greater, and the apparent diffusion coefficient (ADC) ratio was lower in the hpIDC-P than in the lpIDC-P group (P < 0.05). The ROC-AUCs of the stepwise models based solely on imaging features for distinguishing IDC-P from PAC and hpIDC-P from lpIDC-P and PAC were 0.797 (95% confidence interval, 0.750-0.843) and 0.777 (0.727-0.827), respectively.

CONCLUSION

IDC-P was more likely to be larger, more invasive, and more metastatic, with obviously restricted diffusion. EPE, pelvic lymphadenopathy, and a lower ADC ratio were more likely to occur in hpIDC-P, and were also the most useful variables in both nomograms for predicting IDC-P and hpIDC-P.

Incidence and Predicting Factors of Histopathological Features at Robot-Assisted Radical Prostatectomy in the mpMRI Era: Results of a Single Tertiary Referral Center

Background and Objectives: To describe the predictors of cribriform variant status and perineural invasion (PNI) in robot-assisted radical prostatectomy (RARP) histology. To define the rates of upgrading between biopsy specimens and final histology and their possible predictive factors in prostate cancer (PCa) patients undergoing RARP. Material and Methods: Within our institutional database, 265 PCa patients who underwent prostate biopsies and consecutive RARP at our center were enrolled (2018-2022). In the overall population, two independent multivariable logistic regression models (LRMs) predicting the presence of PNI or cribriform variant status at RARP were performed. In low- and intermediate-risk PCa patients according to D'Amico risk classification, three independent multivariable LRMs were fitted to predict upgrading. Results: Of all, 30.9% were low-risk, 18.9% were intermediate-risk and 50.2% were high-risk PCa patients. In the overall population, the rates of the cribriform variant and PNI at RARP were 55.8% and 71.1%, respectively. After multivariable LRMs predicting PNI, total tumor length in biopsy cores (>24 mm [OR: 2.37, p-value = 0.03], relative to <24 mm) was an independent predictor. After multivariable LRMs predicting cribriform variant status, PIRADS (3 [OR:15.37], 4 [OR: 13.57] or 5 [OR: 16.51] relative to PIRADS 2, all p = 0.01) and total tumor length in biopsy cores (>24 mm [OR: 2.47, p = 0.01], relative to <24 mm) were independent predicting factors. In low- and intermediate-risk PCa patients, the rate of upgrading was 74.4% and 78.0%, respectively. After multivariable LRMs predicting upgrading, PIRADS (PIRADS 3 [OR: 7.01], 4 [OR: 16.98] or 5 [OR: 20.96] relative to PIRADS 2, all p = 0.01) was an independent predicting factor. Conclusions: RARP represents a tailored and risk-adapted treatment strategy for PCa patients. The indication of RP progressively migrates to high-risk PCa after a pre-operative assessment. Specifically, the PIRADS score at mpMRI should guide the decision-making process of urologists for PCa patients.

Prostate Cancer Morphologies: Cribriform Pattern and Intraductal Carcinoma Relations to Adverse Pathological and Clinical Outcomes-Systematic Review and Meta-Analysis

The present study aimed to assess the association between the cribriform pattern (CP)/intraductal carcinoma (IDC) and the adverse pathological and clinical outcomes in the radical prostatectomy (RP) cohort. A systematic search was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis statement (PRISMA). The protocol from this review was registered on the PROSPERO platform. We searched PubMed^®, the Cochrane Library and EM-BASE^® up to the 30th of April 2022. The outcomes of interest were the extraprostatic extension (EPE), seminal vesicle invasion (SVI), lymph node metastasis (LNS met), risk of biochemical recurrence (BCR), distant metastasis (MET) and disease-specific death (DSD). As a result, we identified 16 studies with 164 296 patients. A total of 13 studies containing 3254 RP patients were eligible for the meta-analysis. The CP/IDC was associated with adverse outcomes, including EPE (pooled OR = 2.55, 95%CI 1.23-5.26), SVI (pooled OR = 4.27, 95%CI 1.90-9.64), LNs met (pooled OR = 6.47, 95%CI 3.76-11.14), BCR (pooled OR = 5.09, 95%CI 2.23-11.62) and MET/DSD (pooled OR = 9.84, 95%CI 2.75-35.20, p < 0.001). In conclusion, the CP/IDC belong to highly malignant prostate cancer patterns which have a negative impact on both the pathological and clinical outcomes. The presence of the CP/IDC should be included in the surgical planning and postoperative treatment guidance.

Predictive value of Cribriform and Intraductal Carcinoma for the Nomogram-Based Selection of Prostate Cancer Patients for Pelvic Lymph Node Dissection

OBJECTIVE

To assess the predictive value of biopsy-identified cribriform carcinoma and/or intraductal carcinoma (CR/IDC) within the Briganti and MSKCC nomograms predicting lymph node metastasis (LNM) in patients with primary prostate cancer (PCa).

METHODS

We retrospectively included 393 PCa patients who underwent radical prostatectomy with extended pelvic lymph node dissection at three tertiary referral centers. We externally validated two prediction tools: the Briganti 2012 nomogram and the Memorial Sloan Kettering Cancer Center (MSKCC) nomogram. Both nomograms were augmented with CR/IDC. The original model was compared with the CR/IDC-updated model using the likelihood ratio test. The performance of the prediction tools was assessed using calibration, discrimination, and clinical utility.

RESULTS

Overall, 109 (28%) men were diagnosed with LNM. Calibration plots of the Briganti and MSKCC nomograms demonstrated an underestimation of the LNM risk across clinically relevant thresholds (≤15%). The addition of CR/IDC to the Briganti nomogram increased the fit of the data (χ²(1)=4.30, p=0.04), but did not improve the area under the curve (AUC) (0.69, 95% CI 0.63-0.75 vs. 0.69, 95% CI 0.64-0.75). Incorporation of CR/IDC in the MSKCC nomogram resulted in an increased fit on the data (χ²(1)=10.04, p<0.01), but did not increase the AUC (0.66, 95% CI 0.60-0.72 vs 0.68, 95% CI 0.62-0.74). The addition of CR/IDC to the Briganti and MSKCC nomograms did not improve the clinical risk prediction.

CONCLUSIONS

Incorporation of CR/IDC into the two clinically most used pre-radical prostatectomy nomograms does not improve LNM prediction in a multinational, contemporary PCa cohort.

Cribriform Patterned Lesions in the Prostate Gland with Emphasis on Differential Diagnosis and Clinical Significance

Simple Summary

A cribriform structure is defined as a continuous proliferation of cells with intermingled lumina. Various entities may have a cribriform morphology within the prostate gland, ranging from normal, to benign, to borderline and even to malignant lesions. This review summarizes the morphologic features of entities that have a cribriform morphology within the prostate gland, with an emphasis on their differential diagnosis, molecular profile and clinical significance. The basic aim is to assist the pathologist with challenging and controversial cases and inform the clinician on the clinical implications of cribriform morphology.

Abstract

Cribriform glandular formations are characterized by a continuous proliferation of cells with intermingled lumina and can constitute a major or minor part of physiologic (normal central zone glands), benign (clear cell cribriform hyperplasia and basal cell hyperplasia), premalignant (high-grade prostatic intraepithelial neoplasia), borderline (atypical intraductal cribriform proliferation) or clearly malignant (intraductal, acinar, ductal and basal cell carcinoma) lesions. Each displays a different clinical course and variability in clinical management and prognosis. The aim of this review is to summarize the current knowledge regarding the morphological features, differential diagnosis, molecular profile and clinical significance of the cribriform-patterned entities of the prostate gland. Areas of controversy regarding their management, i.e., the grading of Intaductal Carcinoma, will also be discussed. Understanding the distinct nature of each cribriform lesion leads to the correct diagnosis and ensures accuracy in clinical decision-making, prognosis prediction and personalized risk stratification of patients.

Large and small cribriform architecture have similar adverse clinical outcome on prostate cancer biopsies

Aims

Invasive cribriform and intraductal carcinoma (IDC) are associated with adverse outcome in prostate cancer patients, with the large cribriform pattern having the worst outcome in radical prostatectomies. Our objective was to determine the impact of the large and small cribriform patterns in prostate cancer biopsies.

Methods and results

Pathological revision was carried out on biopsies of 1887 patients from the European Randomised Study of Screening for Prostate Cancer. The large cribriform pattern was defined as having at least twice the size of adjacent benign glands. The median follow‐up time was 13.4 years. Hazard ratios for metastasis‐free survival (MFS) and disease‐specific survival (DSS) were calculated using Cox proportional hazards regression. Any cribriform pattern was found in 280 of 1887 men: 1.1% IDC in grade group (GG) 1, 18.2% in GG2, 57.1% in GG3, 55.4% in GG4 and 59.3% in GG5; the large cribriform pattern was present in 0, 0.5, 9.8, 18.1 and 17.3%, respectively. In multivariable analyses, small and large cribriform patterns were both (P < 0.005) associated with worse MFS [small: hazard ratio (HR) = 3.04, 95% confidence interval (CI) = 1.93–4.78; large: HR = 3.17, 95% CI = 1.68–5.99] and DSS (small: HR = 4.07, 95% CI = 2.51–6.62; large: HR = 4.13, 95% CI = 2.14–7.98). Patients with the large cribriform pattern did not have worse MFS (P = 0.77) or DSS (P = 0.96) than those with the small cribriform pattern.

Conclusions

Both small and large cribriform patterns are associated with worse MFS and DSS in prostate cancer biopsies. Patients with the large cribriform pattern on biopsy have a similar adverse outcome as those with the small cribriform pattern.

Intraductal Carcinoma of the Prostate as a Cause of Prostate Cancer Metastasis: A Molecular Portrait

Intraductal carcinoma of the prostate (IDC-P) is one of the most aggressive types of prostate cancer (PCa). IDC-P is identified in approximately 20% of PCa patients and is associated with recurrence, metastasis, and PCa-specific death. The main feature of this histological variant is the colonization of benign glands by PCa cells. Although IDC-P is a well-recognized independent parameter for metastasis, mechanisms by which IDC-P cells can spread and colonize other tissues are not fully known. In this review, we discuss the molecular portraits of IDC-P determined by immunohistochemistry and genomic approaches and highlight the areas in which more research is needed.

Prevalence of adverse pathology features in grade group 2 prostatectomy specimens with syn- or metachronous metastatic disease

BACKGROUND

To validate the importance of recently established adverse histopathology features (cribriform pattern and intraductal carcinoma) as contra-indication for deferred treatment of Gleason score 7 (3 + 4) (grade group [GG] 2) prostate cancer, we investigated their frequency in GG2 radical prostatectomies with syn- or metachronous metastatic disease.

METHODS

GG2 prostatectomy specimens of patients with concomitant lymph node metastasis or distant metastasis at follow-up were identified in a clinical database of a tertiary care center and their pathology was reviewed for pathological stage, lymphovascular invasion, Gleason grade 4 subpatterns, presence of tertiary grade 5, and ductal adenocarcinoma histology. A control group of 99 GG2 prostatectomy specimens who had no metastatic disease (controls) was reviewed for the same adverse pathological features.

RESULTS

Of 1860 GG2 prostatectomy specimens (operated between 2002 and 2020), 45 (2.4%) had concurrent regional lymph node metastases or distant metastases at follow-up. Pathological stage distribution of cases and controls was 24% and 79% pT2, 42% and 15% pT3a, 33% and 6.1% pT3b -T4, respectively (p < 0.001). Eleven of 45 cases (24%) had ≤10% Gleason grade 4 component. Cribriform pattern or intraductal carcinoma was present in 84% of cases versus 34% of controls (p < 0.001), tertiary grade 5 in 16% of cases versus 5% controls (p = 0.05) and ductal adenocarcinoma in 16% of cases versus 2% of controls (p = 0.004). Among the seven cases without cribriform or intraductal carcinoma, two displayed ductal adenocarcinoma features.

CONCLUSIONS

Well-established unfavorable histopathologic features (intraductal and cribriform pattern carcinoma, ductal adenocarcinoma) are represented in about 90% of GG2 prostate cancers with local or distant metastatic disease and are much less common (38%) in those without metastatic disease. Strikingly, about 25% of GG2 prostatectomy cases with metastatic disease had an organ-confined disease and/or a small percentage of Gleason grade 4 pattern. This further emphasizes the relative importance of these adverse histopathological features (cribriform, intraductal, and ductal adenocarcinoma) rather than percentage Gleason grade 4 as contra-indicator of deferred treatment for patients with GG2 prostate cancer.

Anterior or Posterior Prostate Cancer Tumor Nodule Location Predicts Likelihood of Certain Adverse Outcomes at Radical Prostatectomy

CONTEXT.—

Effect of tumor nodule (TN) location in the prostate on adverse radical prostatectomy (RP) outcomes is not well studied in contemporary cohort.

OBJECTIVE.—

To investigate the significance of TN location with respect to extraprostatic extension (EPE), seminal vesicle invasion (SV+), and positive margin status (SM+) in 1388 RPs.

DESIGN.—

Each TN at RP was independently graded, staged, and volumetrically assessed. TNs with at least 80% of their volume occupying either the anterior or posterior part of the prostate were categorized accordingly and included in our study, while all other TNs were excluded.

RESULTS.—

A total of 3570 separate TNs (median = 3 per RP; range = 1-7 per RP) were scored. There were 1320 of 3570 (37%) anterior TNs and 2250 of 3570 (63%) posterior TNs. Posterior TNs were more likely to be higher grade, and exhibit EPE (18% versus 9.4%) and SV+ (4% versus 0.15%), all P < .001. Anterior TNs with EPE were more likely to exhibit SM+ than posterior TNs with EPE (62% versus 30.8%, P < .001). TN location, grade, and volume were significant factors associated with adverse RP outcomes in our univariable analysis. When we controlled for grade and tumor volume in a multivariable analysis using anterior TN location as a reference, posterior TN location was an independent predictor of EPE and SV+ and was less likely to be associated with SM+ (odds ratio = 3.1, 81.5, and 0.7, respectively).

CONCLUSIONS.—

These associations may be useful in preoperative surgical planning, particularly with respect to improving radiographic analysis of prostate cancer.

Intraductal carcinoma of the prostate in prostate biopsy samples: correlation with aggressive pathological features after radical prostatectomy and prognostic value in high-risk prostate cancer

Intraductal carcinoma of the prostate (IDC-P) is an aggressive pathological pattern of prostate cancer (PCa). We investigated the association of IDC-P in prostate biopsy (PBx) with several pathological features after radical prostatectomy (RP) and its prognostic value in high-risk PCa. A total of 418 patients with high-risk PCa after RP were included in this study. IDC-P and its architectural patterns were identified according to the 2016 World Health Organization Classification. Chi-squared test and logistic regression were used to investigate the correlation between IDC-P and post-RP pathological features. Kaplan–Meier curves and Cox regression were applied to explore the prognostic value of IDC-P. IDC-P was identified in PBx in 36/418 (8.6%) patients. Logistic regression indicated that IDC-P in PBx was independently associated with several pathological features of RP, including Gleason score 8–10 (P < 0.001), seminal vesicular invasion (P < 0.001), and pathological T (pT) 3a (P = 0.043). Patients with IDC-P in PBx manifested poorer biochemical-free survival (BFS) than those without IDC-P (37.47 months vs not reached, P < 0.001). The addition of IDC-P in several prognostic nomograms could improve the predictive accuracy of these tools. We conclude that IDC-P in PBx is positively associated with several aggressive pathological features after RP in high-risk PCa. In addition, IDC-P in PBx could effectively predict the BFS of high-risk PCa patients after RP.

Knowing what's growing: Why ductal and intraductal prostate cancer matter

Prostate cancer is a common malignancy, but only some tumors are lethal. Accurately identifying these tumors will improve clinical practice and instruct research. Aggressive cancers often have distinctive pathologies, including intraductal carcinoma of the prostate (IDC-P) and ductal adenocarcinoma. Here, we review the importance of these pathologies because they are often overlooked, especially in genomics and preclinical testing. Pathology, genomics, and patient-derived models show that IDC-P and ductal adenocarcinoma accompany multiple markers of poor prognosis. Consequently, "knowing what is growing" will help translate preclinical research to pinpoint and treat high-risk prostate cancer in the clinic.

The 2019 Genitourinary Pathology Society (GUPS) White Paper on Contemporary Grading of Prostate Cancer

CONTEXT.—

Controversies and uncertainty persist in prostate cancer grading.

OBJECTIVE.—

To update grading recommendations.

DATA SOURCES.—

Critical review of the literature along with pathology and clinician surveys.

CONCLUSIONS.—

Percent Gleason pattern 4 (%GP4) is as follows: (1) report %GP4 in needle biopsy with Grade Groups (GrGp) 2 and 3, and in needle biopsy on other parts (jars) of lower grade in cases with at least 1 part showing Gleason score (GS) 4 + 4 = 8; and (2) report %GP4: less than 5% or less than 10% and 10% increments thereafter. Tertiary grade patterns are as follows: (1) replace "tertiary grade pattern" in radical prostatectomy (RP) with "minor tertiary pattern 5 (TP5)," and only use in RP with GrGp 2 or 3 with less than 5% Gleason pattern 5; and (2) minor TP5 is noted along with the GS, with the GrGp based on the GS. Global score and magnetic resonance imaging (MRI)-targeted biopsies are as follows: (1) when multiple undesignated cores are taken from a single MRI-targeted lesion, an overall grade for that lesion is given as if all the involved cores were one long core; and (2) if providing a global score, when different scores are found in the standard and the MRI-targeted biopsy, give a single global score (factoring both the systematic standard and the MRI-targeted positive cores). Grade Groups are as follows: (1) Grade Groups (GrGp) is the terminology adopted by major world organizations; and (2) retain GS 3 + 5 = 8 in GrGp 4. Cribriform carcinoma is as follows: (1) report the presence or absence of cribriform glands in biopsy and RP with Gleason pattern 4 carcinoma. Intraductal carcinoma (IDC-P) is as follows: (1) report IDC-P in biopsy and RP; (2) use criteria based on dense cribriform glands (>50% of the gland is composed of epithelium relative to luminal spaces) and/or solid nests and/or marked pleomorphism/necrosis; (3) it is not necessary to perform basal cell immunostains on biopsy and RP to identify IDC-P if the results would not change the overall (highest) GS/GrGp part per case; (4) do not include IDC-P in determining the final GS/GrGp on biopsy and/or RP; and (5) "atypical intraductal proliferation (AIP)" is preferred for an intraductal proliferation of prostatic secretory cells which shows a greater degree of architectural complexity and/or cytological atypia than typical high-grade prostatic intraepithelial neoplasia, yet falling short of the strict diagnostic threshold for IDC-P. Molecular testing is as follows: (1) Ki67 is not ready for routine clinical use; (2) additional studies of active surveillance cohorts are needed to establish the utility of PTEN in this setting; and (3) dedicated studies of RNA-based assays in active surveillance populations are needed to substantiate the utility of these expensive tests in this setting. Artificial intelligence and novel grading schema are as follows: (1) incorporating reactive stromal grade, percent GP4, minor tertiary GP5, and cribriform/intraductal carcinoma are not ready for adoption in current practice.

The visibility of prostate cancer concerning underlying histopathological variances: A single-center multiparametric magnetic resonance imaging study

PURPOSE

To investigate whether prostate cancer (PCa) lesions regarding histopathological composition exhibit different morphological features on multiparametric prostate MRI (mpMRI).

METHODS

We investigated men with PCa with available mpMRI and whole-mount specimens between June 2015 to December 2020.The acquisition protocol consistent with the Prostate Imaging Reporting and Data System (PI-RADS). Two observers evaluated the images following the PI-RADS v2.1. guideline before biopsy and radical prostatectomy. The discrepancies were resolved in a joint meeting. A genitourinary pathologist reviewed the whole-digitalized mount specimens, and the lesions with Gleason score of 7 and above (3 + 4 and above), and/or cancers with a maximum diameter of 6 mm and more, and/or extraprostatic extension were accepted as clinically significant PCa. The PI-RADS scores and the diameter of the clinically significant PCa on mpMRI concerning histopathological components (i.e., cribriform component, intraductal pattern, or without cribriform component or intraductal pattern) were investigated. The clinically significant PCa foci with PI-RADS score <3 was accepted as an invisible lesion on mpMRI.

RESULTS

In all, 58 men with a total of 112 clinically significant PCa foci, were enrolled in the study. The intraductal pattern, cribriform pattern, or none of these patterns were observed in 28/112 (25 %), 43/112 (38.05 %), and 41/112 (36.60 %) tumor foci. Six out of 28 (21.42 %), 17/43 (39.53 %), and 18/41 (42.8 %) foci with an intraductal pattern, cribriform component, or without any of them, respectively, were invisible on mpMRI (P = 0.111).

CONCLUSION

Though it was not reached a statistical significance, clinically significant PCa with the cribriform component and without any intraductal or cribriform component are more likely to manifests mpMRI invisible foci than the intraductal pattern. Further multi-center studies are warranted to precisely elucidate mpMRI features of PCa regarding histopathological composition.

Small Cell-like Change in Central Zone Histology-A New Observation Mimicking Cribriform Intraductal Prostatic Adenocarcinoma

A small cell-like change in prostate has been described in high-grade prostatic intraepithelial neoplasia (PIN), intraductal prostatic adenocarcinoma, and invasive prostate cancer. It occurs when these processes have a cribriform architecture. To date, small cell-like change has not been described in benign glands. Herein, I describe such a change in cribriform central zone histology from a radical prostatectomy with a spatially remote treatment naïve Grade Group 3 prostate cancer. The cancer did not have cribriform morphology or intraductal prostatic adenocarcinoma. The small cell-like change was positive for racemase in PIN-4 cocktail and no nuclei were highlighted by Ki-67. This is the first report of a small cell-like change in benign prostate tissue. Although rare, such finding in cribriform architecture of central zone histology can potentially be misinterpreted as a neoplastic process.

Narrative review of prostate cancer grading systems: will the Gleason scores be replaced by the Grade Groups?

The Gleason grading system, proposed by Dr. Donald F. Gleason in 1966, is one of the most important prognostic factors in men with prostate cancer (PCa). At consensus conferences held in 2005 and 2014, organized by the International Society of Urological Pathology (ISUP), the system was modified to reflect the current diagnostic and therapeutic approaches. In particular, in the 2014 Conference, it was recognized that there were weaknesses with the original and the 2005 ISUP modified Gleason systems. Based on the results of a research conducted by Prof. JI Epstein and his group, a new grading system was proposed by the ISUP in order to address some of such deficiencies: i.e., the five distinct Grade Groups (GGs). Since 2014, results of studies have been published by different groups and societies, including the Genitourinary Pathology Society (GUPS), giving additional support to the prognostic role of the architectural Gleason patterns and, in particular, of the GGs. A revised GG system, taking into account the percentage of Gleason pattern (GP) 4, cribriform and intraductal carcinoma, tertiary GP 5, and reactive stroma grade, has shown to have some advantages, however not ready for adoption in the current practice. The aim of this contribution was to review the major updates and recommendations regarding the GPs and GSs, as well as the GGs, trying to give an answer to the following questions: “How has the grade group system been used in the routine?” and “will the Gleason scoring system be replace by the grade groups?” We also discussed the potential implementation in the future of molecular pathology and artificial intelligence in grading to further define risk groups in patients with PCa.

Prostate cancer growth patterns beyond the Gleason score: entering a new era of comprehensive tumour grading

The Gleason grading system is one of the most important factors in clinical decision‐making for prostate cancer patients, and is entirely based on the classification of tumour growth patterns. In recent years it has become clear that some individual growth patterns themselves have independent prognostic value, and could be used for better personalised risk stratification. In this review we summarise recent literature on the clinicopathological value and molecular characteristics of individual prostate cancer growth patterns, and show how these, most particularly cribriform architecture, could alter treatment decisions for prostate cancer patients.

Risk Factors for Pathologically Confirmed Lymph Nodes Metastasis in Patients With Clinical T2N0M0 Stage Prostate Cancer

Objective

To explore the risk factors for postoperatively pathological lymph node metastasis in patients with clinical T2N0M0 stage prostate cancer (PCa).

Methods

We retrospectively analyzed clinicopathological data of 316 patients with clinical T2 stage PCa and preoperative negative lymph nodes [LN(−)] indicated by imaging (cT2N0M0) between January 2014 and May 2019. Multivariate logistic regression analysis was performed to determine risk factors for postoperatively pathological pLN(+) in patients with cT2N0M0 stage PCa. Spearman correlation analysis was used to explore the relationship between tumor burden and Prostate Imaging Reporting and Data System version 2 (PI-RADS v2) score.

Results

A total of 45 patients (14.2%) were confirmed by postoperative pathology to have LN metastasis. Univariate analysis indicated that total prostate-specific antigen (tPSA), PI-RADS v2 score, postoperative Gleason grade group (GGG), intraductal carcinoma of the prostate (IDC-P), clinical T2 substaging, and postoperative pathological tumor burden were risk factors for pLN(+) in all patients. Multivariate analysis showed that tPSA and postoperative GGG were risk factors for pLN(+) in all patients. Univariate analysis revealed that tPSA, PIRADS v2 score, clinical T2 substaging, IDC-P, postoperative pathological tumor burden, and postoperative GGG were risk factors for pLN(+) in patients with GGG ≥ 3. Multivariate analysis suggested that tPSA, PI-RADS v2 score, clinical T2 substaging, postoperative pathological tumor burden, and GGG were risk factors for pLN (+) in patients with GGG ≥ 3. Spearman correlation analysis showed that PI-RADS v2 score was positively correlated with clinical T2 substaging and postoperative pathological tumor burden.

Conclusion

There was a high risk of LN metastasis in patients with cT2 PCa if they had high preoperative tPSA or high postoperative GGG. Patients with cT2 PCa and GGG ≥ 3 had a high risk of LN metastasis if they had high PI-RADS v2 score, high preoperative clinical stage or high postoperative pathological tumor burden. PI-RADS v2 score predicted tumor burden well in patients with GGG ≥ 3.

Isolated Intraductal Carcinoma of the Prostate in Prostatectomy Specimens: Report of 2 Cases and Review of the Literature

Intraductal carcinoma of the prostate (IDCp) is a distinct neoplastic entity, and although recognized for some time, it was included for the first time in the histologic classification of prostate cancer in the 2016 publication of World Health Organization. IDCp represents an intraductal or intra-acinar proliferation of malignant cells, with preservation of the basal cell layer. Even though IDCp is usually accompanied by a high-grade invasive component, low-grade invasive carcinoma can rarely be seen adjacent to the lesion. Even rarer is the incidence of isolated IDCp in needle biopsies, while a few such cases have been reported in prostatectomy specimens. We report 2 cases with isolated IDCp without any invasive component. A review of the literature is performed including the diagnostic challenges of IDCp and its morphologic mimics, immunohistochemical markers, molecular aspects, and prognostic implications. Even though it is not yet clear whether IDCp represents an intraductal spread of invasive cancer or a precursor of invasive carcinoma, the existence of isolated IDCp reinforces the idea that, at least in some of the cases, IDCp is a precancerous lesion. Further molecular studies need to be performed in order to clarify its pathogenesis.

Applied anatomy of pelvic lymph nodes and its clinical significance for prostate cancer:a single-center cadaveric study

Background

Pelvic lymph node dissection (PLND) is one of the most important steps in radical prostatectomy (RP). Not only can PLND provide accurate clinical staging to guide treatment after prostatectomy but PLND can also improve the prognosis of patients by eradicating micro-metastases. However, reports of the number of pelvic lymph nodes have generally come from incomplete dissection during surgery, there is no anatomic study that assesses the number and variability of lymph nodes. Our objective is to assess the utility of adopting the lymph node count as a metric of surgical quality for the extent of lymph node dissection during RP for prostate cancer by conducting a dissection study of pelvic lymph nodes in adult male cadavers.

Methods

All 30 adult male cadavers underwent pelvic lymph node dissection (PLND), and the lymph nodes in each of the 9 dissection zones were enumerated and analyzed.

Results

A total of 1267 lymph nodes were obtained. The number of lymph nodes obtained by limited PLND was 4–22 (14.1 ± 4.5), the number obtained by standard PLND was 16–35 (25.9 ± 5.6), the number obtained by extended PLND was 17–44 (30.0 ± 7.0), and the number obtained by super-extended PLDN was 24–60 (42.2 ± 9.7).

Conclusions

There are substantial inter-individual differences in the number of lymph nodes in the pelvic cavity. These results have demonstrated the rationality and feasibility of adopting lymph node count as a surrogate for evaluating the utility of PLND in radical prostatectomy, but these results need to be further explored.

Historical and contemporary perspectives on cribriform morphology in prostate cancer

The Gleason scoring system is widely used for the grading and prognostication of prostate cancer. A Gleason pattern 4 subtype known as cribriform morphology has now been recognized as an aggressive and often lethal pattern of prostate cancer. The vast majority of published and ongoing prostate cancer studies still do not acknowledge the prognostic differences between various Gleason pattern 4 morphologies. As a result, current treatment recommendations are likely to be imprecise and not tailored towards patients who are most likely to die from the disease. Use of active surveillance for patients with Gleason score 3 + 4 prostate cancer has been suggested. However, the success of such paradigms would require cribriform morphology to be reported at the time of prostate biopsy, as patients harbouring such a pattern are poor candidates for surveillance. To date, only a limited number of studies have described the molecular alterations that occur in the cribriform morphological pattern. Further refinement of prostate cancer grading paradigms to distinguish cribriform from noncribriform Gleason pattern 4 is essential.

The Association of Invasive Cribriform Lesions With Adverse Prostatic Adenocarcinoma Outcomes: An Institutional Experience, Systematic Review, and Meta-analysis

Context.—

Recent studies and a few reviews suggest that presence of invasive cribriform lesions (ICLs) in prostatic acinar adenocarcinoma correlates with adverse outcomes. However, a systematic review with meta-analysis on this correlation is currently lacking.

Objective.—

To compare the likelihood of adverse outcomes by the status of ICLs in prostatic acinar adenocarcinoma with the meta-analysis of high-quality published data and institutional experience.

Data Sources.—

PubMed, Scopus, manually searched references, and institutional data.

Study Selection.—

Observational retrospective case-control studies or prospective cohort studies of adverse outcomes stratified by the status of ICLs were selected.

Data Extraction.—

Study quality was analyzed. The prevalence of adverse outcomes stratified by the status of ICLs was extracted.

Conclusions.—

Eighty-five cases were reviewed. Extraprostatic extension, seminal vesicle invasion, and regional lymph node metastasis were observed in 18 (45%), 14 (35%), and 7 (17.5%) of the 40 cases with cribriform lesions, respectively. These features were observed in 4 (8.9%), 1 (2.2%), and 0 (0%) of the 45 cases without ICLs. During the follow-up, biochemical prostate-specific antigen recurrence, local recurrence, and metastasis/disease-specific death were documented in 7 (17.5%), 2 (5%), and 2 (5%) of the 40 cases with ICLs. These poor outcomes were found in 6 (13.3%), 1 (2.2%), and 1 (2.2%) of the 45 cases without ICLs. Meta-analysis revealed a significant increase in the risk of adverse outcomes in patients who had ICLs relative to those who did not (odds ratio, 3.95; 95% CI, 2.61–5.97; I2 = 53%; Z = 6.52; P &lt; .01). These results suggest that presence of ICLs is associated with adverse outcomes.

Large cribriform growth pattern identifies ISUP grade 2 prostate cancer at high risk for recurrence and metastasis

Invasive cribriform and intraductal carcinoma are associated with adverse clinical outcome in patients with Gleason score 7 prostate cancer. It is yet unclear whether invasive cribriform and intraductal carcinoma of the prostate both have independent prognostic value, or whether field size of invasive cribriform carcinoma has impact on disease outcome. Our objective was to determine the prognostic impact of intraductal and invasive cribriform prostate cancer histological subtypes in radical prostatectomies. We reviewed 420 prostatectomy specimens with ISUP grade 2 prostate cancer, assessed the percentages of Gleason grade 4 and tertiary 5, and performed immunohistochemistry for basal cells to discriminate intraductal from invasive cribriform growth. Small and large invasive cribriform fields were distinguished based on a diameter of at least twice the size of adjacent pre-existent normal glands. Clinicopathological parameters and biochemical recurrence-free survival were used as endpoints. Cribriform architecture was observed in 228 (54.3%) men, 103 (24.5%) of whom had intraductal, 194 (46.2%) small invasive, and 34 (8.1%) large invasive cribriform growth. Large invasive cribriform architecture was associated with older age (P < 0.001), higher percentage Gleason grade 4 (P = 0.001), extraprostatic expansion (P < 0.001), and more frequent lymph node metastases (P = 0.002), when compared with small invasive cribriform and/or intraductal carcinoma. Univariate analysis identified PSA, pT-stage, surgical margin status, and intraductal and invasive cribriform growth as significant predictors for biochemical recurrence-free survival. In multivariable Cox regression analysis, pT-stage (hazard ratio = 1.64, 95% CI: 1.02-2.63, P = 0.04), positive surgical margins (hazard ratio = 3.28, 95% CI: 2.06-5.23, P < 0.001), and large cribriform growth (hazard ratio = 4.36, 95% CI: 2.08-9.17, P < 0.001) were independent predictors for biochemical recurrence-free survival, while intraductal carcinoma, small cribriform growth, and percentage of Gleason grade 4 were not. In conclusion, large cribriform fields represent an aggressive subpattern of invasive cribriform prostate cancer and are an independent predictive factor for biochemical recurrence-free survival in ISUP grade 2 prostate cancer patients.

Updates on Grading and Staging of Prostate Cancer

Since its development between 1966 and 1977, the Gleason grading system has remained one of the most important prognostic indicators in prostatic acinar adenocarcinoma. The grading system was first majorly revised in 2005 and again in 2014. With the publication of the 8th edition of the American Joint Committee on Cancer TNM staging manual in 2018, the classification of prostate cancer and its reporting have further evolved and are now included as part of staging criteria. This article reflects the aspects that are most influential on daily practice. A brief summary of 3 ancillary commercially available genomic tests is also provided.

Large-Gland Proliferations of the Prostate

Large-gland proliferations of the prostate have gained considerable attention in the past decade. The differential diagnosis is quite broad but can be refined using histologic criteria and, sometimes, immunostains. Pathologists have come to realize that cribriform and intraductal as well as ductal carcinomas are particularly aggressive patterns, and should name them in diagnostic reporting when present.

Unfavorable Pathology, Tissue Biomarkers and Genomic Tests With Clinical Implications in Prostate Cancer Management

Prostate cancer management has traditionally relied upon risk stratification of patients based on Gleason score, pretreatment prostate-specific antigen and clinical tumor stage. However, these factors alone do not adequately reflect the inherent complexity and heterogeneity of prostate cancer. Accurate and individualized risk stratification at the time of diagnosis is instrumental to facilitate clinical decision-making and treatment selection tailored to each patient. The incorporation of tissue and genetic biomarkers into current prostate cancer prediction models may optimize decision-making and improve patient outcomes. In this review we discuss the clinical significance of unfavorable morphologic features such as cribriform architecture and intraductal carcinoma of the prostate, tissue biomarkers and genomic tests and assess their potential use in prostate cancer risk assessment and treatment selection.

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.

Prostate cancer with cribriform morphology: diagnosis, aggressiveness, molecular pathology and possible relationships with intraductal carcinoma

INTRODUCTION

The Gleason grading system is one of the most important prognostic factors in prostate cancer (PCa). From the 2005 to the 2014 conference organized by the International Society of Urological Pathology (ISUP), the histological criteria for the Gleason patterns were improved, resulting in the shrinkage of the Gleason pattern (GP) 3 and expansion of the GP 4. Areas Covered: Cribriform, fused, ill-defined and glomeruloid glands are part of the morphologic spectrum of the current GP 4. Cribriform, derived from the Latin word cribrum (i.e. sieve), was introduced by Gleason to describe glands composed of a solid sheet with perforations or lumina. Cribriform morphology has a worse prognosis compared with the other, non-cribriform, GP4 morphologies. A practical implication is that a cribriform growth precludes a patient from selecting an active surveillance (AS) protocol. Expert commentary: The presence of these four growth patterns should be incorporated into the current Grade Group (GG) system. Enhancing our understanding of cribriform tumor behavior will lead to correctly identifying and treating those patients that will die because of PCa, while sparing treatment in those who do not require it.

Cribriform and intraductal prostate cancer are associated with increased genomic instability and distinct genomic alterations

BACKGROUND

Invasive cribriform and intraductal carcinoma (CR/IDC) is associated with adverse outcome of prostate cancer patients. The aim of this study was to determine the molecular aberrations associated with CR/IDC in primary prostate cancer, focusing on genomic instability and somatic copy number alterations (CNA).

METHODS

Whole-slide images of The Cancer Genome Atlas Project (TCGA, N = 260) and the Canadian Prostate Cancer Genome Network (CPC-GENE, N = 199) radical prostatectomy datasets were reviewed for Gleason score (GS) and presence of CR/IDC. Genomic instability was assessed by calculating the percentage of genome altered (PGA). Somatic copy number alterations (CNA) were determined using Fisher-Boschloo tests and logistic regression. Primary analysis were performed on TCGA (N = 260) as discovery and CPC-GENE (N = 199) as validation set.

RESULTS

CR/IDC growth was present in 80/260 (31%) TCGA and 76/199 (38%) CPC-GENE cases. Patients with CR/IDC and ≥ GS 7 had significantly higher PGA than men without this pattern in both TCGA (2.2 fold; p = 0.0003) and CPC-GENE (1.7 fold; p = 0.004) cohorts. CR/IDC growth was associated with deletions of 8p, 16q, 10q23, 13q22, 17p13, 21q22, and amplification of 8q24. CNAs comprised a total of 1299 gene deletions and 369 amplifications in the TCGA dataset, of which 474 and 328 events were independently validated, respectively. Several of the affected genes were known to be associated with aggressive prostate cancer such as loss of PTEN, CDH1, BCAR1 and gain of MYC. Point mutations in TP53, SPOP and FOXA1were also associated with CR/IDC, but occurred less frequently than CNAs.

CONCLUSIONS

CR/IDC growth is associated with increased genomic instability clustering to genetic regions involved in aggressive prostate cancer. Therefore, CR/IDC is a pathologic substrate for progressive molecular tumour derangement.

The New Realization About Cribriform Prostate Cancer

Data from the past 6 years have shown that the presence of any amount of cribriform (or more comprehensively, large acinar cribriform to papillary) pattern of invasive prostate cancer is associated with adverse pathologic features and leads to uniquely adverse outcomes. Sixteen papers and numerous abstracts have reached these conclusions concordantly. Not only does this justify removal of all cribriform cancer from Gleason grade 3, it shows that cribriform cancer has pathologic, outcome, and molecular features distinct from noncribriform Gleason grade 4. Suggestions for accommodating the presence of cribriform cancer into the 2014 Grade Group scheme are proposed.

Evaluation of tumor morphologies and association with biochemical recurrence after radical prostatectomy in grade group 5 prostate cancer

We assessed Gleason pattern 5 (GP5) and other prostatic adenocarcinoma (PCa) morphologies to determine their association with biochemical recurrence (BCR). A search for grade group 5 PCa with radical prostatectomy (RP) yielded 49 patients. RPs were reviewed for %GP5 and morphologies (sheets, single cells, cords, small solid cylinders, solid medium to large nests with rosette-like spaces [SMLNRS], comedonecrosis, cribriform glands, glomerulations, intraductal carcinoma of the prostate [IDC-P], and prostatic ductal adenocarcinoma [PDCa]). Prevalence of morphologies was as follows: single cells 100%, cribriform glands 98.7%, cords 85.7%, IDC-P 77.6%, comedonecrosis 53.1%, sheets 49.0%, small solid cylinders 49.0%, PDCa 44.9%, glomerulations 34.7%, and SMLNRS 14.3%. From 28 patients who were treated with RP as monotherapy, 64.3% (18/28) had BCR. Comedonecrosis, sheets, small solid cylinders, IDC-P, and PDCa were significantly associated with BCR. Number of morphologies on RP and %GP5 were higher in patients with BCR (6.8 ± 2.1 versus 3.7 ± 2.9%; P < 0.001 and 26.9 ± 16.8 versus 11.4 ± 14.1%; P = 0.02) with area under ROC curve of 0.89 (confidence intervals [CI] 0.77-1.00). Sensitivity/specificity was 77.8/80.0% for predicting BCR when ≥ 5 morphologies were present and 0.79 (CI 0.60-0.99) with sensitivity/specificity of 66.7/80.0% for predicting BCR when ≥ 15% GP5 was present. Hazard ratio for BCR was higher with increasing number of morphologies (1.23, CI 1.02-1.49; P = 0.034) but not %GP5 (0.99, CI 0.97-1.02, P = 0.622). Our results indicate that GP5 morphologies may represent a biologically heterogeneous group and that an increasing number of PCa morphologies on RP is strongly associated with an increased risk of BCR.

Radical Prostatectomy Findings in White Hispanic/Latino Men With NCCN Very Low-risk Prostate Cancer Detected by Template Biopsy

Radical prostatectomy (RP) outcomes have been studied in White and Black non-Hispanic men qualifying for Epstein active surveillance criteria (EASC). Herein, we first analyzed such outcomes in White Hispanic men. We studied 70 men with nonpalpable Gleason score 3+3=6 (Grade Group [GG] 1) prostate cancer (PCa) with ≤2 positive cores on biopsy who underwent RP. In 18 men, prostate-specific antigen (PSA) density (PSAD) was >0.15 ng/mL/g. Three of these had insignificant and 15 had significant PCa. The remaining 52 men qualified for EASC. One patient had no PCa identified at RP. Nineteen (37%) had significant PCa defined by volume (n=7), grade (n=7), and volume and grade (n=5). Nine cases were 3+4=7 (GG 2) (5/9 [56%] with pattern 4 <5%), 2 were 3+5=8 (GG 4), and 1 was 4+5=9 (GG 5). Patients with significant PCa more commonly had anterior dominant disease (11/19, 58%) versus patients with insignificant cancer (7/33, 21%) (P=0.01). In 12 cases with higher grade at RP, the dominant tumor nodule was anterior in 6 (50%) and posterior in 6 (median volumes: 1.1 vs. 0.17 cm, respectively; P=0.01). PSA correlated poorly with tumor volume (r=0.28, P=0.049). Gland weight significantly correlated with PSA (r=0.54, P<0.001). While PSAD and PSA mass density correlated with tumor volume, only PSA mass density distinguished cases with significant disease (median, 0.008 vs. 0.012 μg/g; P=0.03). In summary, a PSAD threshold of 0.15 works well in predicting significant tumor volume in Hispanic men. EASC appear to perform better in White Hispanic men than previously reported outcomes for Black non-Hispanic and worse than in White non-Hispanic men. Significant disease is often Gleason score 3+3=6 (GG 1) PCa >0.5 cm. Significant PCa is either a larger-volume anterior disease that may be detected by multiparametric magnetic resonance imaging-targeted biopsy or anterior sampling of the prostate or higher-grade smaller-volume posterior disease that in most cases should not pose immediate harm and may be detected by repeat template biopsies.

Differential Diagnosis of Intraductal Lesions of the Prostate

The category of intraductal lesions of the prostate includes a range of primary prostatic and nonprostatic processes with wide variation in prognosis and recommended follow-up. Studies have shown that pathologists are uncomfortable with the diagnosis of these lesions and that the diagnostic reproducibility is low in this category. Despite the diagnostic difficulty, their accurate and reproducible diagnosis is critical for patient management. This review aims to highlight the diagnostic criteria, prognosis, and treatment implications of common intraductal lesions of the prostate. It focuses on the recognition of intraductal carcinoma of the prostate (IDC-P) in prostate needle biopsies and how to distinguish it from its common mimickers, including high-grade prostatic intraepithelial neoplasia, invasive cribriform prostatic adenocarcinoma, urothelial carcinoma extending into prostatic ducts, and prostatic ductal adenocarcinoma. IDC-P is independently associated with higher risk disease, and its identification in a needle biopsy, even in the absence of invasive carcinoma, should compel definitive treatment. Conversely, high-grade prostatic intraepithelial neoplasia has a much better prognosis and in limited quantities does not even warrant a repeat biopsy. IDC-P must be distinguished from urothelial carcinoma involving prostatic ducts, as recommended treatment varies markedly. Ductal adenocarcinoma may confuse the pathologist and clinician by overlapping terminology, and morphology may also mimic IDC-P on occasion. The use of ancillary testing with immunohistochemistry and molecular markers has also been reviewed.

PTEN loss and p27 loss differ among morphologic patterns of prostate cancer, including cribriform

The presence and extent of cribriform pattern of prostate cancer portend recurrence and cancer death. The relative expressions within this morphology of the prognostically adverse loss of PTEN, and the downstream inactivation of cell cycle inhibitor p27/Kip1 had been uncertain. In this study, we examined 52 cases of cribriform cancer by immunohistochemistry for PTEN, p27, and CD44 variant (v)7/8, and a subset of 17 cases by chromogenic in situ hybridization (ISH) using probes for PTEN or CDKN1B (gene for p27). The fractions of epithelial pixels positive by immunohistochemistry and ISH were digitally assessed for benign acini, high-grade prostatic intraepithelial neoplasia, and 8 morphologic patterns of cancer. Immunostaining results demonstrated that (1) PTEN loss was significant for fused small acini, cribriform-central cells, small cribriform acini, and Gleason grade 5 cells in comparison with other acini; (2) p27 loss was significant only for cribriform-peripheral cells and borderline significant for fused small acini in comparison with benign acini; and (3) CD44v7/8 showed expression loss in cribriform-peripheral cells; other comparisons were not significant. ISH showed that cribriform cancer had significant PTEN loss normalized to benign acini (P<.02), whereas Gleason 3 cancer or fused small acini did not. With CDKN1B, the degree of signal loss among various cancer morphologies was insignificant. In conclusion, molecular disparities emerged between the fused small acini and cribriform patterns of Gleason 4 cancer. PTEN or p27 loss as prognostic factors demands distinct assessment in the varieties of Gleason 4 cancer, and in the biphenotypic peripheral versus central populations in cribriform structures.

Distinct DNA methylation alterations are associated with cribriform architecture and intraductal carcinoma in Gleason pattern 4 prostate tumors

The aim of the present study was to explore DNA methylation aberrations in association with cribriform architecture and intraductal carcinoma (IDC) of the prostate, as there is robust evidence that these morphological features are associated with aggressive disease and have significant clinical implications. Herein, the associations of a panel of seven known prognostic DNA methylation biomarkers with cribriform and IDC features were examined in a series of 91 Gleason pattern (GP) 4 tumors derived from Gleason score 7 radical prostatectomies. Gene specific DNA methylation was compared between cribriform and/or IDC positive vs. negative cases, and in association with clinicopathological features, using Chi square and Mann-Whitney U tests. DNA methylation of the adenomatous polyposis coli, Ras association domain family member 1 and T-box 15 genes was significantly elevated in GP4 tumors with cribriform and/or IDC features compared with negative cases (P=0.045, P=0.007 and P=0.013, respectively). To the best of our knowledge, this provides the first evidence for an association between cribriform and/or IDC and methylation biomarkers, and warrants further investigation of additional DNA methylation events in association with various architectural patterns in prostate cancer.

[The 2014 consensus conference of the ISUP on Gleason grading of prostatic carcinoma]

In 2005 the International Society of Urological Pathology (ISUP) held a concensus conference on Gleason grading in order to bring this grading system up to the current state of contemporary practice; however, it became clear that further modifications on the grading of prostatic carcinoma were necessary. The International Society of Urological Pathology therefore held a further consensus conference in 2014 to clarify these points. This article presents the essential results of the Chicago grading meeting.

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.

Prostate cancer outcomes of men with biopsy Gleason score 6 and 7 without cribriform or intraductal carcinoma

AIM OF THE STUDY

Gleason score (GS) 3 + 4 = 7 prostate cancer patients with presence of cribriform or intraductal carcinoma (7(+)) have a worse disease-specific survival than those without. The aim of this study was to compare the clinicopathologic characteristics and patient outcomes of men with biopsy GS 3 + 4 = 7 without cribriform or intraductal carcinoma (7(-)) to those with GS 3 + 3 = 6.

MATERIALS AND METHODS

We included all patients from the first screening round of the European Randomized Study of Screening for Prostate Cancer (1993-2000) with a revised GS ≤ 3 + 4 = 7 (n = 796) following the 2014 International Society of Urological Pathology criteria. Relations with biochemical recurrence after radical prostatectomy or radiotherapy were analysed using log-rank testing and multivariable Cox regression analysis.

RESULTS

In total, 486 patients had GS 6 and 310 had GS 7, 54 of whom had GS 7(+) (17%). During a median follow-up of 15 years, biochemical recurrence was seen in 61 (20%) GS 6, 54 (21%) GS 7(-) and 22 (41%) GS 7(+) patients (41%). Both biopsy GS 7(-) and 7(+) patients had significantly higher prostate-specific antigen levels, mean tumour percentage, percentage of positive cores and ≥cT3 than those with GS 6 (all P < .001). GS 7(-) patients did not have a poorer biochemical recurrence-free survival (BCRFS) after radical prostatectomy than GS 6 patients (log-rank P = .13), whereas those with GS 7(+) had (log-rank P = .05). In multivariable analyses, biopsy GS 7(-) was not associated with poorer BCRFS after radical prostatectomy (hazard ratio [HR], 1.3; 95% confidence interval [CI]: 0.67-2.4; P = .47) or radiotherapy (HR, 0.88; 95% CI: 0.51-1.5; P = .63). GS 7(+) was independently associated with poorer BCRFS after radical prostatectomy (HR, 3.0; 95% CI: 1.1-7.8; P = .03), but not after radiotherapy (HR, 1.2; 95% CI: 0.58-2.3; P = .67).

CONCLUSIONS

Men with biopsy GS 7(-) prostate cancer have similar BCRFS after radical prostatectomy or radiotherapy to those with GS 6 and may be candidates for active surveillance as long as other inclusion criteria such as on PSA and tumour volume are met.

Utility of Gleason pattern 4 morphologies detected on transrectal ultrasound (TRUS)-guided biopsies for prediction of upgrading or upstaging in Gleason score 3 + 4 = 7 prostate cancer

Selected patients with Gleason score (GS) 3 + 4 = 7 prostate cancer (PCa) detected on transrectal ultrasound (TRUS)-guided biopsies may be considered for active surveillance (AS); however, a proportion of these will harbor more aggressive disease. The purpose of this study was to determine if morphologies of Gleason pattern 4 PCa may predict upgrading and/or upstaging after radical prostatectomy (RP). A database search for men with GS 3 + 4 = 7 PCa diagnosed on TRUS-guided biopsy that underwent RP between January 2010 and October 2015 identified 152 patients. Two blinded genitourinary pathologists independently reviewed the biopsies and assessed ill-defined glands (IDG), fused glands, small or large cribriform patterns, and glomerulations. Patient age, serum prostate-specific antigen (PSA), percentage (%) of biopsy sites involved by 3 + 4 = 7 PCa, and overall extent of pattern 4 were also recorded. GS and stage (presence or absence of extraprostatic extension [EPE]) were retrieved from RP reports. Data were compared using independent t tests and chi-square. Inter-observer agreement was calculated using Cohen's Kappa statistic. Percent of biopsy sites and extent of pattern 4 were compared to statistically significant morphologies using the Spearman correlation. 28.3 % (43/152) of patients were upgraded to GS >3 + 4 = 7 at RP (GS 4 + 3 = 7 [N = 17], GS 4 + 3 = 7 with tertiary pattern 5 [N = 25], and GS 4 + 5 = 9 [N = 1]) and 44.1 % (67/152) showed EPE after RP. PSA was associated with both upgrading (8.5 ± 5.4 vs. 6.9 ± 3.2 ng/mL, [p = 0.04]) and EPE (8.2 ± 4.6 vs. 6.7 ± 3.2 ng/mL, [p = 0.03]). IDG, fused glands, and glomerulations were not associated with upgrading or EPE (p > 0.05) with moderate to strong inter-observer agreement (K = 0.76-0.88). There was strong inter-observer agreement for small and large cribriform formations (K = 0.93 and 0.94, respectively) and both patterns were strongly associated with upgrading (p < 0.001) and EPE (p = 0.02) on RP. Strong associations were observed between increasing number of morphologies and both upgrading (p = 0.0.25) and EPE (p < 0.001). Overall extent of pattern 4 was associated with upgrading (p = 0.009) and EPE (p = 0.019) while percent of sites involved by GS 3 + 4 = 7 was only associated with EPE (p = 0.023). Cribriform morphology correlated to percentage of sites with 3 + 4 and overall extent of pattern 4 (rho = 0.25, p = 0.002, rho = 0.20, p = 0.015, respectively). Presence of cribriform morphology on TRUS-guided biopsy is strongly associated with upgrading and upstaging at RP and shows near-perfect inter-observer agreement whereas IDG, fused glands, and glomerulations were not useful. Cribriform morphology may be of importance when considering treatment plans for patients with intermediate risk PCa.

Significance and outcome of nuclear anaplasia and mitotic index in prostatic adenocarcinomas

OBJECTIVES

The Gleason grading system measures architectural differentiation and disregards nuclear atypia and the cell proliferation index. Several studies have reported that nuclear grade and mitotic index (MI) are prognostically useful.

PATIENTS AND METHODS

This study included 232 radical prostatectomy specimens. Nuclear anaplasia (NA) was determined on the basis of nucleomegali (at least 20µm); vesicular chromatin; eosinophilic macronucleoli, nuclear lobulation, and irregular thickened nuclear membranei. The proportion of area of NA was recorded in each tumor in 10% increments. The MI was defined as the number of mitotic figures in 10 consecutive high-power fields (HPF).

RESULTS

In univariate analysis, significant differences included associations between biochemical prostate-specific antigen recurrence (BCR) and Gleason score, extraprostatic extension, positive surgical margin, the presence of high-pathologic stage, NA≥10% of tumor area, MI≥3/10 HPF, and preoperative prostate-specific antigen. In a stepwise Cox regression model, a positive surgical margin, the presence of a NA≥10% of tumor area, and a MI of≥3/10 HPF were independent predictors of BCR after radical prostatectomy. NA≥10% of tumor area appeared to have a stronger association with outcome than MI≥3/10 HPF, as still associated with BCR when Gleason score was in the model.

CONCLUSIONS

The results of our study showed that, in addition to the conventional Gleason grading system, NA, and MI are useful prognostic parameters while evaluating long-term prognosis in prostatic adenocarcinoma.

Outcome of Gleason 3 + 5 = 8 Prostate Cancer Diagnosed on Needle Biopsy: Prognostic Comparison with Gleason 4 + 4 = 8

PURPOSE

ISUP (International Society for Urologic Pathology) and WHO adopted prognostic Grade Groups 1 to 5 that simplify prostate cancer grading for prognosis. Grade Group 4 is Gleason score 8 cancer, which is heterogeneous, and it encompasses Gleason score 4 + 4 = 8, 3 + 5 = 8 and 5 + 3 = 8. The comparative prognostic implications of these various Gleason scores had not been studied by urological pathologists after a re-review of slides.

MATERIALS AND METHODS

Patients with a highest biopsy Gleason score of 3 + 5 = 8 or 4 + 4 = 8 were included in the study. Controls were cases with a highest Gleason score of 4 + 3 = 7 or 9-10. A total of 423 prostatic biopsy cases accessioned from 2005 to 2013 at 2 institutions were reviewed. Clinicopathological findings and followup (median 33.4 months) were assessed.

RESULTS

Among Gleason score 8 cancers the cancer status outcome in 51 men with Gleason score 3 + 5 = 8 was marginally worse than in 114 with Gleason score 4 + 4 = 8 (p = 0.04). This was driven by a persistent nonmetastatic (after radiation/hormone therapy) cancer rate of 37% among Gleason score 3 + 5 = 8 cases vs 24% among Gleason score 4 + 4 = 8 cases. Conversely, cancer specific survival at 36-month followup was 97.8% in 3 + 5 cases vs 92.6% in 4 + 4 cases but this was not significant (p = 0.089). Cancer specific survival in the Gleason score 8 group was dichotomized by the presence of cribriform growth (p = 0.018). All Gleason score categories did not differ in the fraction of biopsy cores positive, clinical presentation or pathological findings, including the frequency of Gleason pattern 5, in 70 patients who underwent prostatectomy.

CONCLUSIONS

Using the most current standards of prostate cancer grading the prognosis is not different in Gleason score 3 + 5 = 8 and 4 + 4 = 8 cancers. This justifies including both in Grade Group 4.