Digital quantification of five high-grade prostate cancer patterns, including the cribriform pattern, and their association with adverse outcome

Cribriform Prostate Cancer: Clinical Pathologic and Molecular Considerations

Intraductal cribriform (IDC) and invasive cribriform morphologies are associated with worse prostate cancer outcomes. Limited retrospective studies have associated IDC and cribriform morphology with germline mutations in DNA repair genes, particularly BRCA2. These findings, which prompted the National Comprehensive Cancer Network (NCCN) Guidelines for Prostate Cancer and Genetic/Familial High- Risk Assessment to consider germline testing for individuals with IDC/cribriform histology, have been questioned in a recent prospective study. A deepened understanding of the molecular mechanisms driving disease aggressiveness in cribriform morphology is critical to provide more clarity in clinical decision making. This review summarizes the current understanding of IDC and cribriform prostate cancer, with an emphasis on clinical outcomes and molecular alterations.

Computationally Derived Cribriform Area Index from Prostate Cancer Hematoxylin and Eosin Images Is Associated with Biochemical Recurrence Following Radical Prostatectomy and Is Most Prognostic in Gleason Grade Group 2

BACKGROUND

The presence of invasive cribriform adenocarcinoma (ICC), an expanse of cells containing punched-out lumina uninterrupted by stroma, in radical prostatectomy (RP) specimens has been associated with biochemical recurrence (BCR). However, ICC identification has only moderate inter-reviewer agreement.

OBJECTIVE

To investigate quantitative machine-based assessment of the extent and prognostic utility of ICC, especially within individual Gleason grade groups.

DESIGN, SETTING, AND PARTICIPANTS

A machine learning approach was developed for ICC segmentation using 70 RP patients and validated in a cohort of 749 patients from four sites whose median year of surgery was 2007 and with median follow-up of 28 mo. ICC was segmented on one representative hematoxylin and eosin RP slide per patient and the fraction of tumor area composed of ICC, the cribriform area index (CAI), was measured.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The association between CAI and BCR was measured in terms of the concordance index (c index) and hazard ratio (HR).

RESULTS AND LIMITATIONS

CAI was correlated with BCR (c index 0.62) in the validation set of 411 patients with ICC morphology, especially those with Gleason grade group 2 cancer (n = 192; c index 0.66), and was less prognostic when patients without ICC were included (c index 0.54). A doubling of CAI in the group with ICC morphology was prognostic after controlling for Gleason grade, surgical margin positivity, preoperative prostate-specific antigen level, pathological T stage, and age (HR 1.19, 95% confidence interval 1.03-1.38; p = 0.018).

CONCLUSIONS

Automated image analysis and machine learning could provide an objective, quantitative, reproducible, and high-throughput method of quantifying ICC area. The performance of CAI for grade group 2 cancer suggests that for patients with little Gleason 4 pattern, the ICC fraction has a strong prognostic role.

PATIENT SUMMARY

Machine-based measurement of a specific cell pattern (cribriform; sieve-like, with lots of spaces) in images of prostate specimens could improve risk stratification for patients with prostate cancer. In the future, this could help in expanding the criteria for active surveillance.

Cribriform prostate cancer: Morphologic criteria enabling a diagnosis, based on survey of experts

Among four sub-patterns of Gleason grade 4 prostate cancer, voluminous evidence supports that the cribriform pattern holds an unfavorable prognostic impact, as compared with poorly-formed, fused, or glomeruloid. The International Society of Urological Pathology (ISUP) recommends specifying whether invasive grade 4 cancer is cribriform. Recently, ISUP experts published a consensus definition of cribriform pattern highlighting criteria that distinguish it from mimickers. The current study aimed to analyze morphologic features separately to identify those that define the essence of the cribriform pattern. Thirty-two selected photomicrographs were classified by 12 urologic pathologists as: definitely cribriform cancer, probably cribriform, unsure, probably not cribriform, or definitely not cribriform. Consensus was defined as 9/12 agree or disagree, with ≤1 strongly supporting the opposite choice. Final consensus was achieved in 21 of 32 cases. Generalized estimating equation (GEE) model with logit link was fitted to estimate effect of multiple morphologic predictors. Fisher exact test was used for categorical findings. Presence of intervening stroma precluded calling cribriform cancer (p = 0.006). Mucin presence detracted (p = 0.003) from willingness to call cribriform cancer (only 3 cases had mucin). Lumen number was associated with cribriform consensus (p = 0.0006), and all consensus cases had ≥9 lumens. Predominant papillary pattern or an irregular outer boundary detracted (p = NS). Invasive cribriform carcinoma should have absence of intervening stroma, and usually neither papillary pattern, irregular outer boundary, nor very few lumens. Setting the criteria for cribriform will help prevent over- or undercalling this important finding.

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.

Clinical outcome comparison of Grade Group 1 and Grade Group 2 prostate cancer with and without cribriform architecture at the time of radical prostatectomy

Aims

Invasive cribriform and intraductal carcinoma are associated with aggressive disease in Grade Group 2 (GG2) prostate cancer patients. However, the characteristics and clinical outcome of patients with GG2 prostate cancer without cribriform architecture (GG2−) as compared with those with Grade Group 1 (GG1) prostate cancer are unknown. The aim of this study was to investigate the clinical and pathological characteristics of GG1 and GG2− prostate cancer in radical prostatectomy specimens.

Methods and results

We reviewed 835 radical prostatectomy specimens for Grade Group, pT stage, surgical margin status, and the presence of cribriform architecture. Biochemical recurrence‐free survival and metastasis were used as clinical outcomes. GG1 prostate cancer was seen in 207 patients, and GG2 prostate cancer was seen in 420 patients, of whom 228 (54%) showed cribriform architecture (GG2+) and 192 (46%) did not. GG2− patients had higher prostate‐specific antigen levels (9.4 ng/ml versus 7.0 ng/ml; P < 0.001), more often had extraprostatic extension (36% versus 11%; P < 0.001) and had more positive surgical margins (27% versus 17%; P = 0.01) than GG1 patients. GG2− patients had shorter biochemical recurrence‐free survival (hazard ratio 2.7, 95% confidence interval 1.4–4.9; P = 0.002) than GG1 patients. Lymph node and distant metastasis were observed neither in GG2− nor in GG1 patients, but occurred in 22 of 228 (10%) GG2+ patients.

Conclusion

In conclusion, patients with GG2− prostate cancer at radical prostatectomy have more advanced disease and shorter biochemical recurrence‐free survival than those with GG1 prostate cancer, but both groups have a very low risk of developing metastasis.

Comparative influence of cribriform growth and percent Gleason 4 in prostatic biopsies with Gleason 3+4 cancer

The International Society of Urological Pathology endorses specifying presence of cribriform architecture in Gleason (G)4 prostate cancer because of cribriform's aggressiveness. The relative effect of cribriform presence versus percentage G4 within grade group (GG)2 or 3 was uncertain. 194 men's biopsies with GG2 with or without cribriform (excluding glomeruloid from cribriform) and GG3 without cribriform (controls) from 4 years were reviewed. 173 cases had follow-up including 147 GG2 (15/147 or 10% had cribriform) and 26 GG3. Effects of total tumor specimen involvement, %Gleason 4, and cribriform were stratified into prostatectomy (n = 90), radiotherapy (n = 61), and watching waiting (n = 22) groups. Median follow-up duration was 3.32 years (range 1.90-6.18). Biochemical failures in the above 3 cohorts numbered 9 (9/90; 10%), 5 (5/61; 8%), and 13 (13/22; 59%) respectively. In all groups, (GG2+ GG3, n = 173), the HR for C pattern was 1.64. In GG2, cribriform presence (considering glomeruloid as non-cribriform) conferred a hazard ratio (HR) of 1.51 (p = 0.48). It was 1.38, excluding glomeruloid. In watchful waiting cohort only, presence of C conferred a HR of 2.62 (p = 0.086). All remaining comparisons including percent G4, remained not significant. Thus, only in WW group did cribriform pattern presence approach significance. Detection of differences otherwise was not feasible, probably because: 1) biochemical failure is too rare in GG2 cancer; 2) cribriform frequency was only 10% in GG2 (in current study), less than in higher-grade cancer. 3) Use of biopsy tissue is subject to sampling variation which may undersample cribriform pattern, though biopsy forms the basis of treatment decisions.

Cribriform architecture in radical prostatectomies predicts oncological outcome in Gleason score 8 prostate cancer patients

The Gleason score is an important parameter for clinical outcome in prostate cancer patients. Gleason score 8 is a heterogeneous disease including Gleason score 3 + 5, 4 + 4, and 5 + 3 tumors, and encompasses a broad range of tumor growth patterns. Our objective was to characterize individual growth patterns and identify prognostic parameters in Gleason score 8 prostate cancer patients. We reviewed 1064 radical prostatectomy specimens, recorded individual Gleason 4 and 5 growth patterns as well as presence of intraductal carcinoma, and evaluated biochemical recurrence- and metastasis-free survival. Gleason score 8 disease was identified in 140 (13%) patients, of whom 76 (54%) had Gleason score 3 + 5, 46 (33%) 4 + 4, and 18 (13%) 5 + 3 disease. Invasive cribriform and/or intraductal carcinoma (n = 87, 62%) was observed more frequently in Gleason score 4 + 4 (93%) than 3 + 5 (47%; P < 0.001) and 5 + 3 (44%; P < 0.001) patients. Gleason pattern 5 was present in 110 (79%) men: as single cells and/or cords in 99 (90%) and solid fields in 32 (29%) cases. Solid field pattern 5 coexisted with cribriform architecture (23/32, 72%) more frequently than nonsolid pattern 5 cases (36/78, 46%, P = 0.02). In multivariable analysis including age, prostate-specific antigen, pT-stage, surgical margin status, and lymph node metastases, presence of cribriform architecture was an independent parameter for biochemical recurrence-free (hazard ratio (HR) 2.0, 95% confidence interval (CI) 1.0-3.7; P = 0.04) and metastasis-free (HR 3.5, 95% CI 1.0-12.3; P = 0.05) survival. In conclusion, invasive cribriform and/or intraductal carcinoma occurs more frequently in Gleason score 4 + 4 prostate cancer patients than in Gleason score 3 + 5 and 5 + 3, and is an independent parameter for biochemical recurrence and metastasis. Therefore, cribriform architecture has added value in risk stratification of Gleason score 8 prostate cancer patients.

Comedonecrosis Gleason pattern 5 is associated with worse clinical outcome in operated prostate cancer patients

Individual growth patterns and cribriform architecture are increasingly considered in risk stratification and clinical decision-making in men with prostate cancer. Our objective was to establish the prognostic value of individual Gleason 5 patterns in a radical prostatectomy (RP) cohort. We reviewed 1064 RPs and recorded Grade Group (GG), pT-stage, surgical margin status, Gleason 4 and 5 growth patterns as well as intraductal carcinoma. The clinical endpoints were biochemical recurrence and post-operative distant metastasis. Gleason pattern 5 was present in 339 (31.9%) RPs, of which 47 (4.4%) presented as primary, 166 (15.6%) as secondary, and 126 (11.8%) as tertiary pattern. Single cells/cords were present in 321 (94.7%) tumors with Gleason pattern 5, solid fields in 90 (26.5%), and comedonecrosis in invasive carcinoma in 32 (9.4%) tumors. Solid fields demonstrated either a small nested morphology (n = 50, 14.7%) or medium to large solid fields (n = 61, 18.0%). Cribriform architecture was present in 568 (53.4%) RPs. Medium to large solid fields and comedonecrosis coincided with cribriform architecture in all specimens, and were not observed in cribriform-negative cases. In multivariable analysis adjusted for Prostate-Specific Antigen, pT-stage, GG, surgical margin status and lymph node metastases, cribriform architecture (Hazard Ratio (HR) 9.9; 95% Confidence Interval (CI) 3.9-25.5, P < 0.001) and comedonecrosis (HR 2.1, 95% CI 1.2-3.7, P = 0.01) were independent predictors for metastasis-free survival, while single cells/cords (HR 1.2; 95% CI 0.7-1.8, P = 0.55) and medium to large solid fields (HR 1.6, 95% CI 0.9-2.7, P = 0.09) were not. In conclusion, comedonecrosis in invasive carcinoma is an independent prognostic Gleason 5 pattern for metastasis-free survival after RP. These data support the current recommendations to routinely include cribriform pattern in pathology reports and indicate that comedonecrosis should also be commented on.

Similarities and Differences in the 2019 ISUP and GUPS Recommendations on Prostate Cancer Grading: A Guide for Practicing Pathologists

Contemporary subspecialization of practice in prostate pathology has seen a transition to complex, nuanced reporting, where a growing number of histopathologic parameters may signal differences in patient management. In this context, the International Society of Urological Pathology (ISUP) and the Genitourinary Pathology Society (GUPS) both published proceedings papers on the grading of prostate cancer in 2019. Overall, the 2 prostate cancer grading manuscripts reached many of the same conclusions and recommendations. Yet, each consensus was conducted somewhat differently, and in a couple of key areas, each reached different conclusions and recommendations. Herein, sourced from the experience and viewpoints of members of both societies, we provide the practicing pathologist a summary of the shared recommendations, and of the discordances. It is anticipated that these 2 documents will inform future iterations of recommendations and guidelines for reporting prostate cancer by organizations such as the College of American Pathologists, the Royal College of Pathologists, and the European Society of Pathology, which will promote best practices for their respective constituents. Our goal is to provide the practicing pathologist a useful catalog of the main points of both, allowing each practitioner to make informed decisions and understand any divergent opinions as may arise between observers for individual cases.

Prostate biopsy histopathologic features correlate with a commercial gene expression assay's reclassification of patient NCCN risk category

BACKGROUND

For biopsies with Gleason 3 + 3 = 6 or 3 + 4 = 7 prostate cancer, the Genomic Prostate Score (GPS; OncotypeDx) is designed to predict severe pathology at prostatectomy, and, in some cases, recommends reclassification of the National Comprehensive Cancer Network (NCCN) risk category. We hypothesized that certain histopathologic features that were not considered in the original design of the assay actually would be associated with the NCCN risk category change indicated by GPS testing.

METHODS

For patients with recommended NCCN risk category change, the biopsy cores used for GPS were re-reviewed for stromal reaction, chronic inflammation, and tumor nuclear polarization.

RESULTS

Of 520 patients from May 2011 to December 2018, GPS testing suggested NCCN risk reclassification in 131 (25%); 127 of these slides were available. Of these, the NCCN risk category increased from intermediate to high in 8, low to intermediate in 15, very low to low in 1, and decreased from intermediate to low in 32, and low to very low in 71. Biopsies with NCCN risk increase were associated with moderate or severe stromal reaction (p < .001) and chronic inflammation (p < .001); biopsies with NCCN risk decrease were associated with absence of these features. In Gleason 3 + 3 = 6 cases (n = 93), presence of nuclear polarization was associated with NCCN risk decrease and its absence with increase (p < .001).

CONCLUSIONS

Moderate or severe stromal reaction, chronic inflammation, and lack of nuclear polarization in Gleason score 3 + 3 = 6 tumors were each associated with an increase in NCCN risk category indicated by GPS and vice versa. Our results suggest that GPS captures histologic features associated with aggressiveness that are not routinely assessed in standard histopathologic assessments, and that consideration of such histologic features may improve upon current tumor grading approaches.

Differences in survival of prostate cancer Gleason 8-10 disease and the establishment of a new Gleason survival grading system

Background

Although the latest Gleason grading system in 2014 has distinguished between Gleason 3 + 4 and 4 + 3, Gleason 8 and Gleason 9–10 are remained systemically classified.

Methods

A total of 261,125 patients diagnosed with prostate cancer (PCa) were selected between 2005 and 2015 from the Surveillance, Epidemiology, and End Results (SEER) database. We used propensity score matching to balance clinical variables and then compared overall survival (OS) and cancer‐specific survival (CSS) between Gleason score subgroups. We further establish a new Gleason survival grading system based on the hazard ratio (HR) values of each Gleason subgroup. Cox proportional hazards models and Kaplan–Meier curves were used to compare patient survival.

Results

Among PCa patients with Gleason score 8 disease, patients with Gleason 5 + 3 had significantly worse OS and CSS than those with Gleason 3 + 5 (OS: HR = 1.26, p = 0.042; CSS: HR = 1.42, p = 0.005) and 4 + 4 (HR = 1.50 for OS and HR = 1.69 for CSS, p < 0.001 for all). PCa patients with Gleason 5 + 3 and Gleason 4 + 5 may have the similar OS and CSS (reference Gleason score <=6, 5 + 3: OS HR = 2.44, CSS HR = 7.63; 4 + 5: OS HR = 2.40, CSS HR = 8.92; p < 0.001 for all). The new Gleason survival grading system reclassified the grades 4 and 5 of the 2014 updated Gleason grading system into three hierarchical grades, which makes the classification of grades more detailed and accurate.

Conclusion

PCa patients with Gleason 8–10 may have three different survival subgroups, Gleason 3 + 5 and 4 + 4, Gleason 5 + 3 and 4 + 5, and Gleason 5 + 4 and 5 + 5. Our results maximize risk stratification for PCa patients, provide guidance for clinicians to assess their survival and clinical management, and make a recommendation for the next Gleason grading system update.

Prostate cancer with cribriform pattern: Exclusion criterion for active surveillance?

INTRODUCTION

Following the 2014 International Society of Urological Pathology meeting, a rapidly growing body of evidence by several researchers has been demonstrating a poor prognosis in association with cribriform morphology. The aim of our study was to describe the presence of cribriform foci in specimens of radical prostatectomies and to evaluate whether demographic and clinical characteristics are associated with the presence of cribriform pattern.

MATERIALS AND METHODS

This cohort study was based on 70 radical retropubic prostatectomies specimens collected between 2012 and 2016 and evaluated for the association of the cribriform pattern with age, prostate-specific antigen at surgery day, Gleason on biopsy, Gleason after radical prostatectomy, extracapsular extension, vesicles invasion, margins, multiparametric magnetic resonance imaging, and post-operative radiotherapy. Results; From the univariable analysis, biochemical prostatespecific antigen recurrence (p = 0.001), extracapsular extension (p = 0.003), pre-operative prostate-specific antigen (p = 0.017), vesicles invasion, (p = 0.038) and post-operative radiotherapy (p < 0.001) showed an association with the presence of cribriform pattern. There was also a significant difference of cribriform pattern and Gleason 7 in needle biopsy (p = 0.020) and cribriform pattern and Gleason 8 or 9 in radical prostatectomy specimen (p = 0.036).

CONCLUSIONS

In our study, the increase in preoperative prostate-specific antigen had a high association with cribriform pattern. Further evidence is needed to discriminate preoperative prostate specific antigen values that might potentially be associated with the presence of cribriform pattern. Raising our knowledge about the cribriform pattern can be an excellent opportunity to correctly identify and treat patients who will eventually die from prostate cancer, sparing treatment in those who will not.

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.

The 2019 International Society of Urological Pathology Consensus Conference on Prostate Cancer Grading

Modifications recommended by the International Society of Urological Pathology 2019 conference on prostate cancer grading include the mandatory reporting of cribriform pattern and intraductal carcinoma, inclusion of intraductal carcinoma grade in the Gleason score, and separate aggregate reporting for magnetic resonance imaging-targeted lesions.

The 2019 International Society of Urological Pathology (ISUP) Consensus Conference on Grading of Prostatic Carcinoma

Five years after the last prostatic carcinoma grading consensus conference of the International Society of Urological Pathology (ISUP), accrual of new data and modification of clinical practice require an update of current pathologic grading guidelines. This manuscript summarizes the proceedings of the ISUP consensus meeting for grading of prostatic carcinoma held in September 2019, in Nice, France. Topics brought to consensus included the following: (1) approaches to reporting of Gleason patterns 4 and 5 quantities, and minor/tertiary patterns, (2) an agreement to report the presence of invasive cribriform carcinoma, (3) an agreement to incorporate intraductal carcinoma into grading, and (4) individual versus aggregate grading of systematic and multiparametric magnetic resonance imaging-targeted biopsies. Finally, developments in the field of artificial intelligence in the grading of prostatic carcinoma and future research perspectives were discussed.

Clinicopathological characteristics of glomeruloid architecture in prostate cancer

Glomeruloid architecture is the least common Gleason 4 growth pattern in prostate adenocarcinoma. Its clinicopathological features and relation with cribriform architecture, which has been recognized as an adverse feature, remains to be established. Our objective was to investigate clinicopathological features of glomeruloid architecture in radical prostatectomies. We reviewed 1064 radical prostatectomy specimens and recorded Grade Group, pT-stage, margin status, Gleason pattern percentages, and growth patterns. Simple and complex glomerulations were distinguished by gland size and intraluminal cribriform protrusions. Clinical endpoint was biochemical recurrence-free survival. Glomerulations were identified in 365 (34%) specimens. In 472 Grade Group 2 patients, 210 (44%) had simple and 92 (19%) complex glomerulations. Complex glomerulations coincided with cribriform architecture more often than simple glomerulations (67% versus 52%; P = 0.01). Men with simple glomerulations had significantly lower prostate specific antigen (PSA) levels (9.7 versus 12.1 ng/ml; P = 0.03), percentage Gleason pattern 4 (19% versus 25%; P = 0.001), extra-prostatic extension (34% versus 50%; P = 0.01), and positive surgical margins (25% versus 39%; P = 0.04) than those with cribriform architecture. Extra-prostatic extension (37%) and positive surgical margins (30%) in men with complex glomerulations resembled those with simple glomeruloid rather than those with cribriform architecture. In multivariate Cox regression analysis adjusted for PSA, pT-stage, margin status, and lymph node metastases, cribriform architecture had independent predictive value for biochemical recurrence-free survival (hazard ratio (HR)) 1.9; 95% confidence interval (CI) 1.2-2.9; P = 0.004), while simple (HR 0.8; 95% CI 0.5-1.2; P = 0.26) and complex (HR 0.9; 95% CI 0.5-1.6; P = 0.67) glomerulations did not. Both simple and complex glomeruloid architecture are associated with better outcome than cribriform architecture in Grade Group 2 prostate cancer patients. Therefore, glomeruloid pattern and particularly complex glomerulations should not be classified as a cribriform growth pattern variant in radical prostatectomy specimens.

Predicting Insignificant Prostate Cancer: Analysis of the Pathological Outcomes of Candidates for Active Surveillance according to the Pre-International Society of Urological Pathology (Pre-ISUP) 2014 Era Versus the Post-ISUP2014 Era

Purpose

To analyze the difference in the prediction accuracy with an active surveillance (AS) protocol between two eras (pre-International Society of Urological Pathology [pre-ISUP]-2014 vs. post-ISUP2014).

Materials and Methods

We retrospectively analyzed 118 candidates for AS who underwent radical prostatectomy between 2009 and 2017. We divided our patients into two groups (group 1 [n=57], operation date 2009–2015; group 2 [n=61], operation date 2016–2017). Pathologic slides in group 1 were reviewed to distinguish men with cribriform pattern (CP) because the determination of Gleason scores in old era had been based on pre-ISUP2014 classification. Postoperative outcomes in the two eras were analyzed twice: first, all men in group 1 vs. group 2; second, the remaining men after excluding those with CPs in group 1 vs. group 2.

Results

The proportion of men with insignificant prostate cancer (iPCa) was significantly lower in group 1 than in group 2 (36.8% vs. 57.4%, p=0.040). After excluding 11 men with CPs from group 1, those remaining (46 men) were compared again with group 2. In this analysis, the proportion of men with iPCa was similar between the two groups (old vs. contemporary era: 41.3% vs. 57.4%, p=0.146). Nine of 11 men with CP had violated the criteria for iPCa in the earlier comparison.

Conclusions

The accuracy of the AS protocol has been affected by the coexistence of CPs and pure Gleason 6 tumors in the pre-ISUP2014 era. We suggest to use only contemporary (post-ISUP2014) data to analyze the accuracy with AS protocols in future studies.

Expansile cribriform Gleason pattern 4 has histopathologic and molecular features of aggressiveness and greater risk of biochemical failure compared to glomerulation Gleason pattern 4

BACKGROUND

Molecular testing of prostate cancer biopsies with Gleason pattern 4 suggests the expansile cribriform pattern is more aggressive than the glomerulation pattern. These two extreme patterns have not been compared at prostatectomy. We hypothesized that at prostatectomy the expansile cribriform pattern would be associated with histopathologic and molecular features of aggressiveness and with greater risk of biochemical recurrence (BCR) than the glomerulation pattern.

METHODS

In a retrospective cohort study, radical prostatectomy reports with expansile cribriform pattern or glomerulation pattern were analyzed for percentage of total pattern 4, extraprostatic extension (EPE), positive lymph nodes, seminal vesicle invasion (SVI), and intraductal carcinoma (IDC). Cases with pattern 5 or with both expansile cribriform and glomerulations patterns present were excluded. The electronic medical record was reviewed for BCR-free survival and for Decipher test results.

RESULTS

Of 1020 radical prostatectomies from July 2015 to July 2018, 110 (11%) had either expansile cribriform or glomerulation pattern present. The expansile cribriform group was associated with more histopathologic features of aggressiveness, with higher average total percentage pattern 4 (43.7 vs 27.0, P = .002), a trend of greater extensive EPE (32.7% vs 17.2%, P = .06), a trend toward statistical significance of higher rate of SVI (11.5% vs 3.4%, P = .1), greater positive lymph nodes (9.6% vs 0%, P = .02), and a higher percentage of cases with or suspicious for IDC (23.1% vs 8.6%, P = .04). The risk of BCR was 4.4 (1.3-15.4) fold greater for the expansile cribriform group vs the glomerulations group (P = .02). For the 38 patients who underwent Decipher testing, the expansile cribriform group had a high-risk assay category mean score whereas the glomerulations group had an average risk assay category mean score (0.61 vs 0.47, P = .02).

CONCLUSIONS

In a comparison of prostatectomy cases with expansile cribriform pattern to those with glomerulation pattern, the expansile cribriform pattern was associated with more histopathologic features of aggressiveness, greater risk of biochemical failure, and higher scores with a molecular classifier (Decipher) test. These findings underscore the importance of reporting the types of pattern 4 and supports the argument that men with expansile cribriform likely require more aggressive management.

Gleason pattern 4 with cribriform morphology on biopsy is associated with adverse clinicopathological findings in a prospective radical prostatectomy cohort

The prognostic significance of the Gleason grading system has been well established. However, individual Gleason patterns comprise heterogeneous morphologies which might add additional prognostic information. Recent evidence suggests that Gleason pattern 4 with cribriform growth pattern is associated with an adverse prognosis. To determine the association between cribriform pattern on biopsies and pathological findings on subsequent prostatectomies, we evaluated the presence of cribriform architecture in a prospective cohort of 367 men from 2014 to 2018 treated at a single institution. Cribriform architecture was present in 63.5% of all biopsies and was correlated with the overall extent of Gleason pattern 4. In addition, cribriform morphology on biopsy showed a statistically significant association with higher Gleason grade and increased pathological stage and nodal metastasis. In a subset analysis of cases with Grade Group 2 (Gleason score 3 + 4, n = 208), these associations did not reach statistical significance, but the presence of cribriform growth in this subgroup showed a trend toward increased upgrading to Grade Group 5 (Gleason score 9/10) (1 [0.5%] vs. 5 [2.4%], P = 0.06). This large prospective study comparing biopsy and prostatectomy finding of cribriform architecture demonstrates that cribriform pattern 4 is associated with adverse prognostic features and highlights the relevance for recognizing specific morphologies with distinct biological and clinical features.

Spatial density and diversity of architectural histology in prostate cancer: influence on diffusion weighted magnetic resonance imaging

Background

To assess the influence of specific histopathologic patterns on MRI diffusion characteristics by performing rigorous whole-mount/imaging registration and correlating histologic architectures observed in prostate cancer with diffusion characteristics in prostate MRIs.

Methods

Fifty-two whole-mount pathology blocks from 15 patients who underwent multiparametric MRI (mpMRI) at a single institution prior to radical prostatectomy were retrospectively analyzed. Regions containing individual morphologic patterns (N=21 patterns, including variations of cribriforming, expansile sheets, single cells, patterns of early intraluminal complexity, and mucin rupture patterns) were digitally annotated by an expert genitourinary pathologist. Distinct tumor foci on each slide were also assigned a Gleason grade and scored as having any high-risk histologic pattern. Digital sections were aligned to MRI using a patient-specific mold and registered using local mean weighted piecewise transformation based on anatomic control points. Density and presence of morphological patterns was correlated to apparent diffusion coefficient (ADC) signal intensity using mixed effects model accounting for nested intra-foci, intra-patient correlation. Influence of intra-tumoral heterogeneity was assessed by affinity propagation clustering (APC) of morphology features and correlated to foci- and cluster-level ADC metrics.

Results

One hundred eleven distinct tumor foci were evaluated. Beta diversity, reflecting average morphology representation across inter- and intra-foci areas, demonstrated higher intra-tumor diversity within high-risk foci (P<0.05). ADC signal demonstrated an inverse correlation with foci-level Gleason grade (P>0.05), which was strengthened in cluster-level analysis for intra-foci regions containing high-risk morphologies (P=0.017). In voxel-based analysis, dense regions demonstrate lower ADC, but the presence and density for each morphology influenced ADC independently (ANOVA P<0.001).

Conclusions

Architectural features influence ADC characteristics of MRI, with more complex tumors having lower ADC values regulated by presence and density of specific morphologies.

Cribriform Pattern at the Surgical Margin is Highly Predictive of Biochemical Recurrence in Patients Undergoing Radical Prostatectomy

Objectives We investigated the relationship between cribriform patterns and biochemical recurrence in patients with positive surgical margins after radical prostatectomy. Methods This study was based on radical prostatectomy specimens obtained from 817 patients (165 with margin-positive status) collected at a single center between 2010 and 2016. We retrospectively analyzed and compared body mass index, preoperative prostate-specific antigen, Gleason score, operative methods, postoperative Gleason score, pathological T-stage, tumor percentage involvement, lymphatic and perineural invasion, prostate-specific antigen nadir, location and length of the positive margin, cribriform pattern status, and Gleason grade at the surgical margin in terms of their association with biochemical recurrence. Risk factors for biochemical recurrence were also investigated. Results 21% (31/146) of surgical margin-positive patients had a cribriform pattern. Nadir prostate-specific antigen, perineural invasion and biochemical recurrence rates were significantly higher in cribriform pattern present group than absent group (P = 0.031, 0.043 and 0.045, respectively). According to the Cox regression model, postoperative Gleason score, tumor percentage involvement, location and length of the positive margin, and the presence of a cribriform pattern at the surgical margin were significant predictive factors of biochemical recurrence (P = 0.022, &lt; 0.001, 0.015, 0.001, and 0.022, respectively). Moreover, the biochemical recurrence risk was approximately 3-fold higher in patients with a cribriform pattern at the surgical margin than in those without (HR: 3.41, 95% CI 1.20-9.70, P = 0.022). Conclusions A cribriform pattern at the surgical margin is a significant predictor of biochemical recurrence in patients who undergo radical prostatectomy.

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.

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.

Active surveillance for intermediate-risk prostate cancer: yes, but for whom?

PURPOSE OF REVIEW

Active surveillance is becoming more widely accepted as an initial management option for carefully selected men with favorable intermediate-risk prostate cancer (PCa). As prospective active surveillance cohorts mature sufficiently to begin evaluating longer-term outcomes, consensus on more precise evidence-based guidelines is needed to identify the patient cohorts who may be safely managed with active surveillance and what the ideal surveillance protocol entails.

RECENT FINDINGS

Long-term outcomes updates have suggested a trend toward worse 15-year survival outcomes for intermediate-risk patients on active surveillance compared with definitive treatment, but 'intermediate-risk' is a broad category and there is a subset of favorable intermediate-risk patients for whom survival outcomes remain equivalent. Promising updates to current risk stratification include consideration of genomic classifiers, advanced imaging and more nuanced interpretation of biopsy results.

SUMMARY

Despite widespread acknowledgement of the pitfalls of overtreatment in clinically localized PCa, utilization of active surveillance in the intermediate-risk population remains marginal, in part due to the absence of easily interpretable consensus recommendations. As more long-term outcomes data become available for this subgroup, the field is now poised to refine the definition of favorable intermediate-risk patients for whom active surveillance is a safe, evidence-based first-line management option.

Improved Prostate Cancer Biopsy Grading by Incorporation of Invasive Cribriform and Intraductal Carcinoma in the 2014 Grade Groups

BACKGROUND

Grade groups (GGs) are an important parameter for therapeutic decision making in prostate cancer (Pca) patients. Invasive cribriform and/or intraductal carcinoma (CR/IDC) has an independent prognostic value for disease outcome, but are not included in the GG limiting their clinical use.

OBJECTIVE

To perform a proof-of-principle study incorporating CR/IDC in the current GG.

DESIGN, SETTING, AND PARTICIPANTS

All prostate biopsies of 1031 men with screen-detected Pca between 1993 and 2000 were reviewed for the current GG (ranging from 1 to 5) and CR/IDC. The cribriform grade (cGrade) was equal to the GG if CR/IDC was present and GG minus 1 if not. GG1 was cGrade1 if intraductal carcinoma was absent.

INTERVENTION

Biopsy review for GG and CR/IDC. A total of 406 patients had received radical prostatectomy (RP), 508 radiotherapy (RT), 108 surveillance, and eight hormonal therapy, and the treatment was unknown for one patient. Outcome measurements and statistical analysis disease-specific survival (DSS), metastasis-free survival (MFS), and biochemical recurrence-free survival (BCRFS) after 15.1 yr (interquartile range 10.9-19.7 yr) follow-up were compared using Harrell's C-statistic.

RESULTS AND LIMITATIONS

The biopsy GGs were 486 GG1, 310 GG2, 104 GG3, 64 GG4, and 67 GG5; cGrade distributions were 738 cGrade1, 102 cGrade2, 91 cGrade3, 58 cGrade4, and 42 cGrade5. The cGrade had a better discriminative value than the GG for DSS (C-index 0.79; 95% confidence interval 0.74-0.83 vs 0.76; 0.71-0.82) and MFS (0.79; 0.74-0.84 vs 0.77; 0.72-0.82). The discriminative value for BCRFS after RP and RT was similar for both models. Different diagnostic, such as use of sextant biopsies, and therapeutic strategies in the 1990s are the limitations of this study.

CONCLUSIONS

The cGrade is a simple Pca grade modification with better discriminative values for DSS and MFS than the GG, particularly impacting decision making in men with current GG2 Pca.

PATIENT SUMMARY

Microscopic grading is an important factor for decision making in prostate cancer (Pca) patients. We show that a simple grade modification better predicts Pca outcome and might improve treatment choices.

Syntaphilin Is a Novel Biphasic Biomarker of Aggressive Prostate Cancer and a Metastasis Predictor

Easily accessible biomarkers that may inform on the metastatic potential of localized prostate cancer are urgently needed. Herein, we show that syntaphilin (SNPH), a molecule originally identified as a negative regulator of mitochondrial dynamics in neurons, is abundantly expressed in prostate cancer. SNPH distribution in prostate cancer is spatially biphasic, with high expression at the invasive front, correlating with increased proliferative rates, as determined by Ki-67 labeling, and reduced levels in the central tumor bulk, which are further decreased in patients with distant metastases. Higher levels of SNPH are observed with increasing Gleason grade. Prostate tumors predominantly express a novel, extraneuronal isoform of SNPH that accumulates in mitochondria and maintains oxidative metabolism and tumor cell proliferation. These data suggest that SNPH is a novel marker of high Gleason grade prostate cancer, differentially expressed at the invasive front compared with the central tumor bulk, and is potentially down-regulated in metastatic disease. This biphasic pattern of expression may reflect a dual function of SNPH in controlling the balance between cell proliferation and invasion in tumors.

Artificial intelligence at the intersection of pathology and radiology in prostate cancer

Pathologic grading plays a key role in prostate cancer risk stratification and treatment selection, traditionally assessed from systemic core needle biopsies sampled throughout the prostate gland. Multiparametric magnetic resonance imaging (mpMRI) has become a well-established clinical tool for detecting and localizing prostate cancer. However, both pathologic and radiologic assessment suffer from poor reproducibility among readers. Artificial intelligence (AI) methods show promise in aiding the detection and assessment of imaging-based tasks, dependent on the curation of high-quality training sets. This review provides an overview of recent advances in AI applied to mpMRI and digital pathology in prostate cancer which enable advanced characterization of disease through combined radiology-pathology assessment.

Grading of prostate cancer: a work in progress

Grading of prostate cancer has evolved substantially over time, not least because of major changes in diagnostic approach and concomitant shifts from late- to early-stage detection since the adoption of PSA testing from the late 1980s. After the conception of the architecture-based nine-tier Gleason grading system more than 50 years ago, several changes were made in order to increase its prognostic impact, to reduce interobserver variation and to improve concordance between prostate needle biopsy and radical prostatectomy grading. This eventually resulted in the current five-tier grading system, with a much more detailed description of the individual architectural patterns constituting the remaining three Gleason patterns (i.e. grades 3-5). Nevertheless, there is room for improvement. For instance, distinction of common grade 4 subpatterns such as ill-formed and fused glands from the grade 3 pattern is challenging, blurring the division between low-risk patients who could be eligible for deferred therapy and those who need curative therapy. The last few years have witnessed the publication of several studies on the prognostic impact of individual architectural subpatterns showing that, in particular, the cribriform pattern exceeded the prognostic impact of other grade 4 subpatterns. This review provides an overview of the changes in prostate cancer grading over time and provides a thorough description of the various Gleason subpatterns, the current evidence of their prognostic impact and areas of contention. Potential practical ways for improvements of the current grading system are also put forward.

Essential Updates in Grading, Morphotyping, Reporting, and Staging of Prostate Carcinoma for General Surgical Pathologists

CONTEXT.—

Within this decade, several important updates in prostate cancer have been presented through expert international consensus conferences and influential publications of tumor classification and staging.

OBJECTIVE.—

To present key updates in prostate carcinoma.

DATA SOURCES.—

The study comprised a review of literature and our experience from routine and consultation practices.

CONCLUSIONS.—

Grade groups, a compression of the Gleason system into clinically meaningful groups relevant in this era of active surveillance and multidisciplinary care management for prostate cancer, have been introduced. Refinements in the Gleason patterns notably result in the contemporarily defined Gleason score 6 cancers having a virtually indolent behavior. Grading of tertiary and minor higher-grade patterns in radical prostatectomy has been clarified. A new classification for prostatic neuroendocrine tumors has been promulgated, and intraductal, microcystic, and pleomorphic giant cell carcinomas have been officially recognized. Reporting the percentage of Gleason pattern 4 in Gleason score 7 cancers has been recommended, and data on the enhanced risk for worse prognosis of cribriform pattern are emerging. In reporting biopsies for active surveillance criteria-based protocols, we outline approaches in special situations, including variances in sampling or submission. The 8th American Joint Commission on Cancer TNM staging for prostate cancer has eliminated pT2 subcategorization and stresses the importance of nonanatomic factors in stage groupings and outcome prediction. As the clinical and pathology practices for prostate cancer continue to evolve, it is of utmost importance that surgical pathologists become fully aware of the new changes and challenges that impact their evaluation of prostatic specimens.

Persistent Homology for the Quantitative Evaluation of Architectural Features in Prostate Cancer Histology

The current system for evaluating prostate cancer architecture is the Gleason grading system which divides the morphology of cancer into five distinct architectural patterns, labeled 1 to 5 in increasing levels of cancer aggressiveness, and generates a score by summing the labels of the two most dominant patterns. The Gleason score is currently the most powerful prognostic predictor of patient outcomes; however, it suffers from problems in reproducibility and consistency due to the high intra-observer and inter-observer variability amongst pathologists. In addition, the Gleason system lacks the granularity to address potentially prognostic architectural features beyond Gleason patterns. We evaluate prostate cancer for architectural subtypes using techniques from topological data analysis applied to prostate cancer glandular architecture. In this work we demonstrate the use of persistent homology to capture architectural features independently of Gleason patterns. Specifically, using persistent homology, we compute topological representations of purely graded prostate cancer histopathology images of Gleason patterns 3,4 and 5, and show that persistent homology is capable of clustering prostate cancer histology into architectural groups through a ranked persistence vector. Our results indicate the ability of persistent homology to cluster prostate cancer histopathology images into unique groups with dominant architectural patterns consistent with the continuum of Gleason patterns. In addition, of particular interest, is the sensitivity of persistent homology to identify specific sub-architectural groups within single Gleason patterns, suggesting that persistent homology could represent a robust quantification method for prostate cancer architecture with higher granularity than the existing semi-quantitative measures. The capability of these topological representations to segregate prostate cancer by architecture makes them an ideal candidate for use as inputs to future machine learning approaches with the intent of augmenting traditional approaches with topological features for improved diagnosis and prognosis.

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.

Genetic and Epigenetic Determinants of Aggressiveness in Cribriform Carcinoma of the Prostate

Among prostate cancers containing Gleason pattern 4, cribriform morphology is associated with unfavorable clinicopathologic factors, but its genetic features and association with long-term outcomes are incompletely understood. In this study, genetic, transcriptional, and epigenetic features of invasive cribriform carcinoma (ICC) tumors were compared with non-cribriform Gleason 4 (NC4) in The Cancer Genome Atlas (TCGA) cohort. ICC (n = 164) had distinctive molecular features when compared with NC4 (n = 102). These include: (i) increased somatic copy number variations (SCNV), specifically deletions at 6q, 8p and 10q, which encompassed PTEN and MAP3K7 losses and gains at 3q; (ii) increased SPOP mut and ATMmut ; (iii) enrichment for mTORC1 and MYC pathways by gene expression; and (iv) increased methylation of selected genes. In addition, when compared with the metastatic prostate cancer, ICC clustered more closely to metastatic prostate cancer than NC4. Validation in clinical cohorts and genomically annotated murine models confirmed the association with SPOPmut (n = 38) and PTENloss (n = 818). The association of ICC with lethal disease was evaluated in the Health Professionals Follow-up Study (HPFS) and Physicians' Health Study (PHS) prospective prostate cancer cohorts (median follow-up, 13.4 years; n = 818). Patients with ICC were more likely to develop lethal cancer [HR, 1.62; 95% confidence interval (CI), 1.05-2.49], independent from Gleason score (GS). IMPLICATIONS: ICC has a distinct molecular phenotype that resembles metastatic prostate cancer and is associated with progression to lethal disease.

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.

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.

Cribriform Subtype is an Independent Predictor of Recurrence and Survival After Adjustment for the Eighth Edition of TNM Staging System in Patients With Resected Lung Adenocarcinoma

INTRODUCTION

At present, cribriform arrangements are regarded as a pattern of acinar adenocarcinoma. However, recent studies have indicated that clinical outcomes for lung adenocarcinoma patients with cribriform subtype are unfavorable. To validate the prognostic significance of the cribriform pattern, we analyzed a series of 735 Japanese patients with resected lung adenocarcinoma, which was restaged according to the eighth edition of the TNM staging system.

METHODS

Tumors were classified in accordance with the 2015 WHO classification of lung carcinomas. The cribriform pattern was defined by invasive back-to-back fused tumor glands with poorly formed glandular spaces or invasive tumor nests of tumors cells that produce glandular lumina. Recurrence-free probability (RFP) and overall survival (OS) was analyzed using the log-rank test and the Cox proportional hazards model.

RESULTS

After the addition of the cribriform pattern, 54 of 90 acinar-predominant tumors were reclassified as cribriform subtype. Five-year RFP for patients with the cribriform subtype (51%) was lower than it was for patients with acinar and papillary subtype (81% and 80%, respectively) but was comparable to that for patients with solid subtype (48%). Five-year OS for patients with the cribriform subtype (49%) was lower than it was for patients with acinar and papillary subtype (90% and 81%, respectively). On multivariate analysis adjusted for the eighth edition of the TNM staging system, the cribriform subtype was an independent prognostic factor of a worse RFP and OS.

CONCLUSIONS

We have validated that the cribriform subtype is an independent factor of poor prognosis in patients with resected lung adenocarcinoma.

Clinical significance of subtypes of Gleason pattern 4 prostate cancer

Major updates in prostate cancer grading have been adopted in recent times. These include redefinitions of Gleason pattern (GP) 4 architectural variants and reporting of the grade group (GG) system, which divides prostate cancer into five groups that better stratify patients. Still, the GG system uses the GPs 3, 4 or 5 to define each GG. Patients belonging to GG 2, 3 and 4 have increasing amounts of GP 4 in the composition of their tumors. GP4 is a heterogeneous group of morphologic variants that include poorly formed glands, glomeruloid structures, cribriform glands, and fused glands. Recently published studies suggest that the morphologic subtypes of GP 4 have different clinical significance. While the diagnostic reproducibility of poorly formed glands and fused glands is low, glomeruloid structures and cribriform glands are easier to be distinguished from other morphologies. A growing body of evidence suggests that the presence of cribriform glands is associated with an aggressive clinical course compared with other architectural subtypes. The latest 2014 guidelines issued by the International Society of Urologic Pathology recommend that the percentage of GP 4 be reported on needle biopsies and radical prostatectomy (RP) specimens. The data reviewed here invites consideration for the need to report the subtype of GP 4, especially the presence or absence of cribriform glands.

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.

Clinical Significance of Complex Glandular Patterns in Lung Adenocarcinoma: Clinicopathologic and Molecular Study in a Large Series of Cases

Objectives

To explore whether complex glandular patterns (CGPs) have a potential role in the clinical management of patients with lung adenocarcinoma.

Methods

We included 356 patients with lung adenocarcinoma with available clinicopathologic information, gene mutations, and clinical outcomes for analysis.

Results

We identified 54 (15.2%) CGP-predominant cases. The CGPs were associated with ALK rearrangement and HER2 mutation. Survival analysis showed that the clinical outcome of CGP-predominant patients was worse than that for acinar-predominant patients (overall survival [OS], 66.4 vs 90.3 months, P < .01; recurrence-free survival [RFS], 50.1 vs 73.1 months, P = .022) but was comparable with solid-predominant subtype tumors (OS, 66.4 vs 67.8 months, P = .558; RFS, 50.1 vs 41.3 months, P = .258). In particular, the coexistence of the cribriform and fused gland pattern was associated with the poorest survival, with a death risk increased by 2.25-fold (hazard ratio, 3.25; 95% confidence interval, 1.35-7.86, P = .009).

Conclusions

Our results provide new insight into the potential role of CGPs in clinical management and will be beneficial for treatment decision making in patients with lung adenocarcinoma.

The present and future of prostate cancer histopathology

PURPOSE OF REVIEW

The present review describes recent changes in the histologic grading of prostatic adenocarcinoma and emerging data suggesting areas for further grade optimization.

RECENT FINDINGS

The grading of prostatic adenocarcinoma has evolved over time, and optimization for active surveillance management has been one major driving force. Recent changes include adoption of the Grade Group system, which stratifies patients into one of five prognostic groups. Although it provides clearer labels for patient understanding and defines a more homogenous low-risk group (i.e. Grade Group 1 of 5), emerging data suggest that further prognostic stratification may be achieved by incorporating other histologic findings. The impact of 'cribriform histology' and intraductal carcinoma as aggressive features of prostate cancer has gained significant recognition. Furthermore, quantifying the fraction of each individual Gleason pattern component may also add prognostic stratification. In addition to Gleason score and Grade Group, some institutions now identify and report high-risk histologic patterns (e.g. 'cribriform histology') and the percentage of Gleason pattern 4 on biopsies. While early in adoption, these additional features are being used to further stratify patients beyond the Grade Group system, particularly for patients with Grade Group 2 carcinomas. These histologic findings will likely be incorporated into future modifications of the grading system to further optimize patient stratification and ensure reporting consistency.

SUMMARY

The histologic evaluation of prostatic adenocarcinoma provides strong prognostic information for clinical management. The recent Grade Group system offers many improvements, but further optimization based on specific histologic patterns may evolve.

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.

Radio-pathomic Maps of Epithelium and Lumen Density Predict the Location of High-Grade Prostate Cancer

PURPOSE

This study aims to combine multiparametric magnetic resonance imaging (MRI) and digitized pathology with machine learning to generate predictive maps of histologic features for prostate cancer localization.

METHODS AND MATERIALS

Thirty-nine patients underwent MRI prior to prostatectomy. After surgery, tissue was sliced according to MRI orientation using patient-specific 3-dimensionally printed slicing jigs. Whole-mount sections were annotated by our pathologist and digitally contoured to differentiate the lumen and epithelium. Slides were co-registered to the T2-weighted MRI scan. A learning curve was generated to determine the number of patients required for a stable machine-learning model. Patients were randomly stratified into 2 training sets and 1 test set. Two partial least-squares regression models were trained, each capable of predicting lumen and epithelium density. Predicted density values were calculated for each patient in the test dataset, mapped into the MRI space, and compared between regions confirmed as high-grade prostate cancer.

RESULTS

The learning-curve analysis showed that a stable fit was achieved with data from 10 patients. Maps indicated that regions of increased epithelium and decreased lumen density, generated from each independent model, corresponded with pathologist-annotated regions of high-grade cancer.

CONCLUSIONS

We present a radio-pathomic approach to mapping prostate cancer. We find that the maps are useful for highlighting high-grade tumors. This technique may be relevant for dose-painting strategies in prostate radiation therapy.

Investigation of Physical Phenomena Underlying Temporal-Enhanced Ultrasound as a New Diagnostic Imaging Technique: Theory and Simulations

Temporal-enhanced ultrasound (TeUS) is a novel noninvasive imaging paradigm that captures information from a temporal sequence of backscattered US radio frequency data obtained from a fixed tissue location. This technology has been shown to be effective for classification of various in vivo and ex vivo tissue types including prostate cancer from benign tissue. Our previous studies have indicated two primary phenomena that influence TeUS: 1) changes in tissue temperature due to acoustic absorption and 2) micro vibrations of tissue due to physiological vibration. In this paper, first, a theoretical formulation for TeUS is presented. Next, a series of simulations are carried out to investigate micro vibration as a source of tissue characterizing information in TeUS. The simulations include finite element modeling of micro vibration in synthetic phantoms, followed by US image generation during TeUS imaging. The simulations are performed on two media, a sparse array of scatterers and a medium with pathology mimicking scatterers that match nuclei distribution extracted from a prostate digital pathology data set. Statistical analysis of the simulated TeUS data shows its ability to accurately classify tissue types. Our experiments suggest that TeUS can capture the microstructural differences, including scatterer density, in tissues as they react to micro vibrations.

On cribriform prostate cancer

The management of newly diagnosed prostate cancer is challenging because of its heterogeneity in histology, genetics and clinical outcome. The clinical outcome of patients with Gleason score 7 prostate cancer varies greatly. Improving risk assessment in this group is of particular interest, as Gleason score 7 prostate cancer on biopsy is an important clinical threshold for active treatment. Architecturally, four Gleason grade 4 growth patterns are recognized: ill-formed, fused, glomeruloid and cribriform. The aim of this review is to describe the role of cribriform growth in prostate cancer with respect to diagnosis, prognosis and molecular pathology. Secondly, we will discuss clinical applications for cribriform prostate cancer and give recommendations for future research.

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.