Histologic Grading of Prostatic Adenocarcinoma Can Be Further Optimized: Analysis of the Relative Prognostic Strength of Individual Architectural Patterns in 1275 Patients From the Canary Retrospective Cohort

Morphologic patterns observed in prostate biopsy cases with discrepant grade group and molecular risk classification

BACKGROUND

Molecular-based risk classifier tests are increasingly being utilized by urologists and radiation oncologists to guide clinical decision making. The Decipher prostate biopsy test is a 22-gene RNA biomarker assay designed to predict likelihood of high-grade disease at radical prostatectomy and risk of metastasis and mortality. The test provides a risk category of low, intermediate, or high. We investigated histologic features of biopsies in which the Grade Group (GG) and Decipher risk category (molecular risk) were discrepant.

METHODS

Our institutional urologic outcomes database was searched for men who underwent prostate biopsies with subsequent Decipher testing from 2016 to 2020. We defined discrepant GG and molecular risk as either GG1-2 with high Decipher risk category or GG ≥ 3 with low Decipher risk category. The biopsy slide on which Decipher testing was performed was re-reviewed for GG and various histologic features, including % Gleason pattern 4, types of Gleason pattern 4 and 5, other "high risk" features (e.g., complex papillary, ductal carcinoma, intraductal carcinoma [IDC]), and other unusual and often "difficult to grade" patterns (e.g., atrophic carcinoma, mucin rupture, pseudohyperplastic carcinoma, collagenous fibroplasia, foamy gland carcinoma, carcinoma with basal cell marker expression, carcinoma with prominent vacuoles, and stromal reaction). Follow-up data was also obtained from the electronic medical record.

RESULTS

Of 178 men who underwent prostate biopsies and had Decipher testing performed, 41 (23%) had discrepant GG and molecular risk. Slides were available for review for 33/41 (80%). Of these 33 patients, 23 (70%) had GG1-2 (GG1 n = 5, GG2 n = 18) with high Decipher risk, and 10 (30%) had GG ≥ 3 with low Decipher risk. Of the 5 GG1 cases, one case was considered GG2 on re-review; no other high risk features were identified but each case showed at least one of the following "difficult to grade" patterns: 3 atrophic carcinoma, 1 collagenous fibroplasia, 1 carcinoma with mucin rupture, and 1 carcinoma with basal cell marker expression. Of the 18 GG2 high Decipher risk cases, 2 showed GG3 on re-review, 5 showed large cribriform and/or other high risk features, and 10 showed a "difficult to grade" pattern. Of the 10 GG ≥ 3 low Decipher risk cases, 5 had known high risk features including 2 with large cribriform, 1 with IDC, and 1 with Gleason pattern 5.

CONCLUSIONS

In GG1-2 high Decipher risk cases, difficult to grade patterns were frequently seen in the absence of other known high risk morphologic features; whether these constitute true high risk cases requires further study. In the GG ≥ 3 low Decipher risk cases, aggressive histologic patterns such as large cribriform and IDC were observed in half (50%) of cases; therefore, the molecular classifier may not capture all high risk histologic patterns.

Proposal for an optimised definition of adverse pathology (unfavourable histology) that predicts metastatic risk in prostatic adenocarcinoma independent of grade group and pathological stage

AIMS

Histological grading of prostate cancer is a powerful prognostic tool, but current criteria for grade assignment are not fully optimised. Our goal was to develop and test a simplified histological grading model, based heavily on large cribriform/intraductal carcinoma, with optimised sensitivity for predicting metastatic potential.

METHODS AND RESULTS

Two separate non-overlapping cohorts were identified: a 419-patient post-radical prostatectomy cohort with long term clinical follow-up and a 209-patient post-radical prostatectomy cohort in which all patients had pathologically confirmed metastatic disease. All prostatectomies were re-reviewed for high-risk histological patterns of carcinoma termed 'unfavourable histology'. Unfavourable histology is defined by any classic Gleason pattern 5 component, any large cribriform morphology (> 0.25 mm) or intraductal carcinoma, complex intraluminal papillary architecture, grade 3 stromogenic carcinoma and complex anastomosing cord-like growth. For the outcome cohort, Kaplan-Meier analysis compared biochemical recurrence, metastasis and death between subjects with favourable and unfavourable histology, stratified by pathological stage and grade group. Multivariable Cox proportional hazards models evaluated adding unfavourable histology to the Memorial Sloan Kettering Cancer Center (MSKCC) post-prostatectomy nomogram and stratification by percentage of unfavourable histology. At 15 years unfavourable histology predicted biochemical recurrence, with sensitivity of 93% and specificity of 88%, metastatic disease at 100 and 48% and death at 100 and 46%. Grade group 2 prostate cancers with unfavourable histology were associated with metastasis independent of pathological stage, while those without had no risk. Histological models for prediction of metastasis based on only large cribriform/intraductal carcinoma or increasing diameter of cribriform size improved specificity, but with lower sensitivity. Multivariable Cox proportional hazards models demonstrated that unfavourable histology significantly improved discriminatory power of the MSKCC post-prostatectomy nomogram for biochemical failure (likelihood ratio test P < 0.001). In the retrospective review of a separate RP cohort in which all patients had confirmed metastatic disease, none had unequivocal favourable histology.

CONCLUSIONS

Unfavourable histology at radical prostatectomy is associated with metastatic risk, predicted adverse outcomes better than current grading and staging systems and improved the MSKCC post-prostatectomy nomogram. Most importantly, unfavourable histology stratified grade group 2 prostate cancers into those with and without metastatic potential, independent of stage. While unfavourable histology is driven predominantly by large cribriform/intraductal carcinoma, the recognition and inclusion of other specific architectural patterns add to the sensitivity for predicting metastatic disease. Moreover, a simplified dichotomous model improves communication and could increase implementation.

Histologically Overt Stromal Response and the Risk of Progression after Radical Prostatectomy for Prostate Cancer

PURPOSE

Given the variable clinical course of prostate cancer and the limitations of current prognostic factors, this study was conducted to investigate the impact of a histologically overt stromal response (HOST-response) to prostate cancer on clinical outcomes after radical prostatectomy.

METHODS

This retrospective analysis utilized The Cancer Genome Atlas (TCGA) to evaluate data from individuals with a confirmed diagnosis of prostate cancer who underwent radical prostatectomy and had available pathology slides. These slides were assessed for the presence of a HOST-response, similar to desmoplasia. The primary endpoint was progression-free survival (PFS). A multivariable competing risk regression analysis was used to assess whether a significant association existed between HOST-response and PFS, adjusting for known prostate cancer prognostic factors.

RESULTS

Among the 348 patients analyzed, 166 (47.70%) demonstrated a HOST-response. After a median follow-up of 37.87 months (IQR: 21.20, 65.50), the presence of a HOST-response was significantly associated with a shorter PFS (SDHR, 2.10; 95% CI, 1.26 to 3.50; p = 0.004), after adjusting for covariates.

CONCLUSIONS

HOST-response in prostate cancer patients treated with radical prostatectomy is significantly associated with reduced PFS, suggesting a potential benefit from adjuvant therapy and highlighting the need for further investigation in a prospective randomized clinical trial.

Contemporary Diagnostic Reporting for Prostatic Adenocarcinoma: Morphologic Aspects, Molecular Correlates, and Management Perspectives

The diagnosis and reporting of prostatic adenocarcinoma have evolved from the classic framework promulgated by Dr Donald Gleason in the 1960s into a complex and nuanced system of grading and reporting that nonetheless retains the essence of his remarkable observations. The criteria for the "Gleason patterns" originally proposed have been continually refined by consensuses in the field, and Gleason scores have been stratified into a patient-friendly set of prognostically validated and widely adopted Grade Groups. One product of this successful grading approach has been the opportunity for pathologists to report diagnoses that signal carefully personalized management, placing the surgical pathologist's interpretation at the center of patient care. At one end of the continuum of disease aggressiveness, personalized diagnostic care means to sub-stratify patients with more indolent disease for active surveillance, while at the other end of the continuum, reporting histologic markers signaling aggression allows sub-stratification of clinically significant disease. Whether contemporary reporting parameters represent deeper nuances of more established ones (eg, new criteria and/or quantitation of Gleason patterns 4 and 5) or represent additional features reported alongside grade (intraductal carcinoma, cribriform patterns of carcinoma), assessment and grading have become more complex and demanding. Herein, we explore these newer reporting parameters, highlighting the state of knowledge regarding morphologic, molecular, and management aspects. Emphasis is made on the increasing value and stakes of histopathologists' interpretations and reporting into current clinical risk stratification and treatment guidelines.

Large cribriform glands (> 0.25 mm diameter) as a predictor of adverse pathology in men with Grade Group 2 prostate cancer

AIMS

A recent outcome-based, radical prostatectomy study defined > 0.25 mm diameter to distinguish large versus small cribriform glands, with > 0.25 mm associated with worse recurrence-free survival. This study evaluates whether identification of > 0.25 mm cribriform glands in Grade Group 2 patients at biopsy is associated with adverse pathology at radical prostatectomy.

METHODS AND RESULTS

Tumours containing biopsy slides for 133 patients with Grade Group 2 prostate cancer with subsequent radical prostatectomy were re-reviewed for large cribriform glands (diameter > 0.25 mm). The primary outcome was adverse pathology (Grade Groups 3-5; stage pT3a or greater, or pN1). The secondary outcome was recurrence-free survival. Cribriform pattern was present in 52 of 133 (39%) patients; of these, 16 of 52 (31%) had large cribriform glands and 36 of 52 (69%) had only small cribriform glands. Patients with large cribriform glands had significantly more adverse pathology at radical prostatectomy compared to patients with small cribriform glands and no cribriform glands (large = 11 of 16, 69%; small = 12 of 36, 33%; no cribriform = 25 of 81, 31%; χ2 P-value 0.01). On multivariate analysis, large cribriform glands were also associated with adverse pathology, independent of age, prostate-specific antigen (PSA)/PSA density at diagnosis, year of diagnosis and biopsy cores percentage positive (global P-value 0.02). Large cribriform glands were also associated with increased CAPRA-S surgical risk score (Kruskal-Wallis P-value 0.02).

CONCLUSIONS

Large cribriform glands using a diameter > 0.25 mm definition in Grade Group 2 patients on biopsy are associated with increased risk of adverse pathology at radical prostatectomy. The presence of large cribriform histology should be considered when offering active surveillance for those with Grade Group 2 disease.

Quantification of collagen content and stromal cellularity within reactive stroma is predictive of prostate cancer biochemical recurrence and specific death

Semiquantitative reactive stromal grading has been shown to be a predictor of biochemical recurrence and prostate cancer (PCa) specific death. It has been extensively validated. In this study we tested novel technologies to introduce quantitative measures of host response, in particular collagen content and stromal cellularity. We use 3 large retrospective cohorts, the Baylor College of Medicine cohort, the Brady cohort and the Pound cohort. Slides were stained and digitized using image deconvolution and analyzed using image segmentation and image analyses. PicroSirius red stain histochemical stains were used for collagen quantification. Area of cancer and stroma were measured independently, without regard to quality of stroma. Cellularity, in each compartment, was measured using image deconvolution, image segmentation and image analysis. Two biomarkers were tested in 3 independent cohorts with two endpoints, biochemical recurrence and prostate cancer specific death. Stromal cellularity (qCollCell) and stromal collagen area (qCollArea) are independently predictive biochemical recurrence in the Hopkins Brady cohort, particularly in Gleason 6-7 patients. Multivariate analysis demonstrated that increased stroma cellularity (qCollCell) was a significant predictor of PCa specific death, when compared to an established model of PCa, in the Baylor cohort. Stromal collagen (qCollArea) independently predicts PCa-specific death in the Hopkins Pound cohort. The introduction of a computerized quantitative test of the host response increases the probability that this test will be reproducible in other cohorts. The ability to improve prediction of prostate cancer specific death might lie in the study of the host and its response.

Analysis of genetic biomarkers, polymorphisms in ADME-related genes and their impact on pharmacotherapy for prostate cancer

Prostate cancer (PCa) is a non-cutaneous malignancy in males with wide variation in incidence rates across the globe. It is the second most reported cause of cancer death. Its etiology may have been linked to genetic polymorphisms, which are not only dominating cause of malignancy casualties but also exerts significant effects on pharmacotherapy outcomes. Although many therapeutic options are available, but suitable candidates identified by useful biomarkers can exhibit maximum therapeutic efficacy. The single-nucleotide polymorphisms (SNPs) reported in androgen receptor signaling genes influence the effectiveness of androgen receptor pathway inhibitors and androgen deprivation therapy. Furthermore, SNPs located in genes involved in transport, drug metabolism, and efflux pumps also influence the efficacy of pharmacotherapy. Hence, SNPs biomarkers provide the basis for individualized pharmacotherapy. The pharmacotherapeutic options for PCa include hormonal therapy, chemotherapy (Docetaxel, Mitoxantrone, Cabazitaxel, and Estramustine, etc.), and radiotherapy. Here, we overview the impact of SNPs reported in various genes on the pharmacotherapy for PCa and evaluate current genetic biomarkers with an emphasis on early diagnosis and individualized treatment strategy in PCa.

High-Grade Desmoplastic Foamy Gland Prostatic Adenocarcinoma

CONTEXT.—

It is important to recognize high-grade foamy gland prostatic adenocarcinoma with desmoplastic stroma given its aggressive clinical course with frequent metastases and death.

OBJECTIVE.—

To review the morphology, immunohistochemistry, and prognosis for this rare subtype of prostate adenocarcinoma.

DESIGN.—

Twenty-four cases received for consultation from 2010 to 2021 were analyzed including needle biopsy (n = 21), transurethral resection (n = 2), and a cystoprostatectomy (n = 1).

RESULTS.—

Patients ranged in age from 40 to 89 years (mean, 67 years). On average, 8 cores per case were involved (mean 67% core involvement). Extraprostatic extension and seminal vesicle invasion were observed in 6 of 21 (29%) and 3 of 21 (14%) needle biopsy cases, respectively. Twenty of the 24 cases (83%) were Grade Group (GG) 5 with 4 of 24 (17%) being GG4. Tumor necrosis as a component of Gleason pattern 5 was observed in 21 of 24 cases (88%). Associated intraductal adenocarcinoma (IDC) was observed in 22 of 24 cases (92%), with 4 of 24 cases (17%) demonstrating extensive IDC. Diagnostic challenges were as follows: (1) sparse isolated cancer glands embedded in the dense desmoplastic stroma; (2) fragmented glands; and (3) aberrant staining for high-molecular-weight cytokeratin in a nonbasal cell pattern in all cases. PTEN loss was observed in 9 cases, and p53 nuclear accumulation was observed in 8 cases. Three patients were lost to follow-up. Overall, of the 16 patients with meaningful follow-up, 12 (75%) either had metastases or died from prostate cancer.

CONCLUSIONS.—

High-grade desmoplastic foamy gland adenocarcinoma is difficult to diagnose and grade and has a poor prognosis.

"Stromal cells in prostate cancer pathobiology: friends or foes?"

The genomic, epigenetic and metabolic determinants of prostate cancer pathobiology have been extensively studied in epithelial cancer cells. However, malignant cells constantly interact with the surrounding environment-the so-called tumour microenvironment (TME)-which may influence tumour cells to proliferate and invade or to starve and die. In that regard, stromal cells-including fibroblasts, smooth muscle cells and vasculature-associated cells-constitute an essential fraction of the prostate cancer TME. However, they have been largely overlooked compared to other cell types (i.e. immune cells). Indeed, their importance in prostate physiology starts at organogenesis, as the soon-to-be prostate stroma determines embryonal epithelial cells to commit toward prostatic differentiation. Later in life, the appearance of a reactive stroma is linked to the malignant transformation of epithelial cells and cancer progression. In this Review, we discuss the main mesenchymal cell populations of the prostate stroma, highlighting their dynamic role in the transition of the healthy prostate epithelium to cancer. A thorough understanding of those populations, their phenotypes and their transcriptional programs may improve our understanding of prostate cancer pathobiology and may help to exploit prostate stroma as a biomarker of patient stratification and as a therapeutic target.

NUSAP1 Binds ILF2 to Modulate R-Loop Accumulation and DNA Damage in Prostate Cancer

Increased expression of NUSAP1 has been identified as a robust prognostic biomarker in prostate cancer and other malignancies. We have previously shown that NUSAP1 is positively regulated by E2F1 and promotes cancer invasion and metastasis. To further understand the biological function of NUSAP1, we used affinity purification and mass spectrometry proteomic analysis to identify NUSAP1 interactors. We identified 85 unique proteins in the NUSAP1 interactome, including ILF2, DHX9, and other RNA-binding proteins. Using proteomic approaches, we uncovered a function for NUSAP1 in maintaining R-loops and in DNA damage response through its interaction with ILF2. Co-immunoprecipitation and colocalization using confocal microscopy verified the interactions of NUSAP1 with ILF2 and DHX9, and RNA/DNA hybrids. We showed that the microtubule and charged helical domains of NUSAP1 were necessary for the protein-protein interactions. Depletion of ILF2 alone further increased camptothecin-induced R-loop accumulation and DNA damage, and NUSAP1 depletion abolished this effect. In human prostate adenocarcinoma, NUSAP1 and ILF2 mRNA expression levels are positively correlated, elevated, and associated with poor clinical outcomes. Our study identifies a novel role for NUSAP1 in regulating R-loop formation and accumulation in response to DNA damage through its interactions with ILF2 and hence provides a potential therapeutic target.

A tissue miRNA expression pattern is associated with disease aggressiveness of localized prostate cancer

BACKGROUND

Prostate cancer (PCa) is a heterogeneous malignancy with high variability in clinical course. Insufficient stratification according to the aggressiveness at the time of diagnosis causes unnecessary or delayed treatment. Current stratification systems are not effective enough because they are based on clinical, surgical or biochemical parameters, but do not take into account molecular factors driving PCa cancerogenesis. MicroRNAs (miRNAs) are important players in molecular pathogenesis of PCa and could serve as valuable biomarkers for the assessment of disease aggressiveness and its prognosis.

METHODS

In the study, in total, 280 PCa patients were enrolled. The miRNA expression profiles were analyzed in FFPE PCa tissue using the miRCURY LNA miRNA PCR System. The expression levels of candidate miRNAs were further verified by two-level validation using the RT-qPCR method and evaluated in relation to PCa stratification reflecting the disease aggressiveness.

RESULTS

MiRNA profiling revealed 172 miRNAs dysregulated between aggressive (ISUP 3-5) and indolent PCa (ISUP 1) (p < 0.05). In the training and validation cohort, miR-15b-5p and miR-106b-5p were confirmed to be significantly upregulated in tissue of aggressive PCa when their level was associated with disease aggressiveness. Furthermore, we established a prognostic score combining the level of miR-15b-5p and miR-106b-5p with serum PSA level, which discriminated indolent PCa from an aggressive form with even higher analytical parameters (AUC being 0.9338 in the training set and 0.8014 in the validation set, respectively). The score was also associated with 5-year biochemical progression-free survival (bPFS) of PCa patients.

CONCLUSIONS

We identified a miRNA expression pattern associated with disease aggressiveness in prostate cancer patients. These miRNAs may be of biological interest as the focus can be also set on their specific role within the molecular pathology and the molecular mechanism that underlies the aggressivity of prostate cancer.

Reprint of: morphologic spectrum of treatment-related changes in prostate tissue and prostate cancer: an updated review

A wide range of treatment options are available to patients with prostate cancer. Some treatments are standard (currently used) while some are emerging therapies. Androgen deprivation therapy is typically reserved for localized or metastatic prostate cancer not amenable to surgery. Radiation therapy may be offered to individuals for local therapy with curative intent in low- or intermediate-risk disease that may have a high probability of progression on active surveillance or where surgery is not suitable. Focal therapy/ablation treatment is an alternative approach for those who prefer to avoid radical prostatectomy for localized disease of low- or intermediate-risk or as salvage therapy after failed radiation therapy. Chemotherapy and immunotherapy remain under investigation and are currently used for androgen-independent disease or hormone-refractory prostate cancer; however, a better understanding of therapeutic efficacy is needed. Histopathologic changes observed in benign and malignant prostate tissue induced by hormonal therapies and radiation therapy are well described, whereas treatment-related effects secondary to novel therapies continue to be documented although their clinical significance is not absolutely clear. An informed and accurate evaluation of post-treatment prostate specimens requires pathologists with diagnostic acumen and knowledge relating to the histopathologic spectrum associated with each treatment option. In situations when clinical history is lacking, but morphologic features are suggestive of prior treatment, pathologists are encouraged to consult clinical colleagues regarding prior treatment history including details of when treatment was initiated and duration of therapy. This review aims to provide a concise update of current and emerging therapies for prostate cancer, histologic alterations and recommendations on Gleason grading.

An update on computational pathology tools for genitourinary pathology practice: A review paper from the Genitourinary Pathology Society (GUPS)

Machine learning has been leveraged for image analysis applications throughout a multitude of subspecialties. This position paper provides a perspective on the evolutionary trajectory of practical deep learning tools for genitourinary pathology through evaluating the most recent iterations of such algorithmic devices. Deep learning tools for genitourinary pathology demonstrate potential to enhance prognostic and predictive capacity for tumor assessment including grading, staging, and subtype identification, yet limitations in data availability, regulation, and standardization have stymied their implementation.

Single cell analysis of cribriform prostate cancer reveals cell intrinsic and tumor microenvironmental pathways of aggressive disease

Cribriform prostate cancer, found in both invasive cribriform carcinoma (ICC) and intraductal carcinoma (IDC), is an aggressive histological subtype that is associated with progression to lethal disease. To delineate the molecular and cellular underpinnings of ICC/IDC aggressiveness, this study examines paired ICC/IDC and benign prostate surgical samples by single-cell RNA-sequencing, TCR sequencing, and histology. ICC/IDC cancer cells express genes associated with metastasis and targets with potential for therapeutic intervention. Pathway analyses and ligand/receptor status model cellular interactions among ICC/IDC and the tumor microenvironment (TME) including JAG1/NOTCH. The ICC/IDC TME is hallmarked by increased angiogenesis and immunosuppressive fibroblasts (CTHRC1⁺ASPN⁺FAP⁺ENG⁺) along with fewer T cells, elevated T cell dysfunction, and increased C1QB⁺TREM2⁺APOE⁺-M2 macrophages. These findings support that cancer cell intrinsic pathways and a complex immunosuppressive TME contribute to the aggressive phenotype of ICC/IDC. These data highlight potential therapeutic opportunities to restore immune signaling in patients with ICC/IDC that may afford better outcomes.

WHO Classification of Tumours fifth edition: evolving issues in the classification, diagnosis, and prognostication of prostate cancer

The fifth edition of the WHO Classification of Tumours of the Urinary and Male Genital Systems encompasses several updates to the classification and diagnosis of prostatic carcinoma as well as incorporating advancements in the assessment of its prognosis, including recent grading modifications. Some of the salient aspects include: (1) recognition that prostatic intraepithelial neoplasia (PIN)-like carcinoma is not synonymous with a pattern of ductal carcinoma, but better classified as a subtype of acinar adenocarcinoma; (2) a specific section on treatment-related neuroendocrine prostatic carcinoma in view of the tight correlation between androgen deprivation therapy and the development of prostatic carcinoma with neuroendocrine morphology, and the emerging data on lineage plasticity; (3) a terminology change of basal cell carcinoma to "adenoid cystic (basal cell) cell carcinoma" given the presence of an underlying MYB::NFIB gene fusion in many cases; (4) discussion of the current issues in the grading of acinar adenocarcinoma and the prognostic significance of cribriform growth patterns; and (5) more detailed coverage of intraductal carcinoma of prostate (IDC-P) reflecting our increased knowledge of this entity, while recommending the descriptive term atypical intraductal proliferation (AIP) for lesions falling short of IDC-P but containing more atypia than typically seen in high-grade prostatic intraepithelial neoplasia (HGPIN). Lesions previously regarded as cribriform patterns of HGPIN are now included in the AIP category. This review discusses these developments, summarising the existing literature, as well as the emerging morphological and molecular data that underpins the classification and prognostication of prostatic carcinoma.

Enrichment of "Cribriform" morphologies (intraductal and cribriform adenocarcinoma) and genomic alterations in radiorecurrent prostate cancer

Locally relapsed prostate cancer (PCa) after radiation therapy (RT) is associated with substantial morbidity and mortality. Morphological and molecular consequences that may contribute to RT resistance and local recurrence remain poorly understood. Locally recurrent PCa tissue from 53 patients with clinically localized PCa who failed with primary RT and subsequently underwent salvage radical prostatectomy (RP) was analyzed for tumor focality, clinicopathological, molecular, and genomic characteristics. Targeted next-generation sequencing with full exon coverage of 1,425 cancer-related genes was performed on 10 representative radiorecurrent PCas exhibiting no RT effect with matched adjacent benign prostate tissue. At RP, 37 (70%) of PCas had no RT effect with the following characteristics: grade group (GG) ≥ 3 (70%), unifocal tumor (75%), extraprostatic disease (78%), lymph node metastasis (8%), and "cribriform" morphologies (84%) [cribriform PCa (78%) or intraductal carcinoma (IDC-P) (61%)] at a median percentage of approximately 80% of tumor volume. In the setting of multifocal tumors (25%) at RP, the cribriform morphologies were restricted to index tumors. Of 32 patients with available pre-RT biopsy information, 16 had GG1 PCa, none had cribriform morphologies at baseline but 81% demonstrated cribriform morphologies at RP. Notable alterations detected in the sequenced tumors included: defects in DNA damage response and repair (DDR) genes (70%) (TP53, BRCA2, PALB2, ATR, POLQ), PTEN loss (50%), loss of 8p (80%), and gain of MYC (70%). The median tumor mutational burden was 4.18 mutations/Mb with a range of 2.16 to 31.86. Our findings suggest that most radiorecurrent PCas are enriched in cribriform morphologies with potentially targetable genomic alterations. Understanding this phenotypic and genotypic diversity of radiorecurrent PCa is critically important to facilitate optimal patient management.

Analysis of separate training and validation radical prostatectomy cohorts identifies 0.25 mm diameter as an optimal definition for "large" cribriform prostatic adenocarcinoma

Cribriform growth pattern is well-established as an adverse pathologic feature in prostate cancer. The literature suggests "large" cribriform glands associate with aggressive behavior; however, published studies use varying definitions for "large". We aimed to identify an outcome-based quantitative cut-off for "large" vs "small" cribriform glands. We conducted an initial training phase using the tissue microarray based Canary retrospective radical prostatectomy cohort. Of 1287 patients analyzed, cribriform growth was observed in 307 (24%). Using Kaplan-Meier estimates of recurrence-free survival curves (RFS) that were stratified by cribriform gland size, we identified 0.25 mm as the optimal cutoff to identify more aggressive disease. In univariable and multivariable Cox proportional hazard analyses, size >0.25 mm was a significant predictor of worse RFS compared to patients with cribriform glands ≤0.25 mm, independent of pre-operative PSA, grade, stage and margin status (p < 0.001). In addition, two different subset analyses of low-intermediate risk cases (cases with Gleason score ≤ 3 + 4 = 7; and cases with Gleason score = 3 + 4 = 7/4 + 3 = 7) likewise demonstrated patients with largest cribriform diameter >0.25 mm had a significantly lower RFS relative to patients with cribriform glands ≤0.25 mm (each subset p = 0.004). Furthermore, there was no significant difference in outcomes between patients with cribriform glands ≤ 0.25 mm and patients without cribriform glands. The >0.25 mm cut-off was validated as statistically significant in a separate 419 patient, completely embedded whole-section radical prostatectomy cohort by biochemical recurrence, metastasis-free survival, and disease specific death, even when cases with admixed Gleason pattern 5 carcinoma were excluded. In summary, our findings support reporting cribriform gland size and identify 0.25 mm as an optimal outcome-based quantitative measure for defining "large" cribriform glands. Moreover, cribriform glands >0.25 mm are associated with potential for metastatic disease independent of Gleason pattern 5 adenocarcinoma.

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.

Morphologic spectrum of treatment-related changes in prostate tissue and prostate cancer: An Updated Review

A wide range of treatment options is available to patients with prostate cancer. Some treatments are standard (currently used) while some are emerging therapies. Androgen deprivation therapy is typically reserved for localized or metastatic prostate cancer not amenable to surgery. Radiation therapy may be offered to individuals for local therapy with curative intent in low- or intermediate-risk disease that may have a high probability of progression on active surveillance or where surgery is not suitable. Focal therapy/ablation treatment is an alternative approach for those who prefer to avoid radical prostatectomy for localized disease of low- or intermediate-risk or as salvage therapy following failed radiation therapy. Chemotherapy and immunotherapy remain under investigation and are currently used for androgen-independent disease or hormone-refractory prostate cancer; however a better understand therapeutic efficacy is needed. Histopathologic changes observed in benign and malignant prostate tissue induced by hormonal therapies and radiation therapy is well described, while treatment-related effects secondary to novel therapies continue to be documented although their clinical significance is not absolutely clear. An informed and accurate evaluation of post-treatment prostate specimens requires pathologists with diagnostic acumen and knowledge relating to the histopathologic spectrum associated with each treatment option. In situations when clinical history is lacking, but morphologic features are suggestive of prior treatment, pathologists are encouraged to consult clinical colleagues regarding prior treatment history including details of when treatment was initiated and duration of therapy. This review aims to provide a concise update of current and emerging therapies for prostate cancer, histologic alterations and recommendations on Gleason grading.

Primary prostatic signet ring cell carcinoma in elderly with obstructive uropathy: a case report

Background

Primary signet-ring cell carcinoma (SRCC) of the prostate is a rare and aggressive subtype of prostate adenocarcinoma with a poor prognosis, with only approximately 60 cases reported worldwide.

Case presentation

A 62-year-old man presented with acute urinary retention and hematuria, after a year’s history of lower urinary tract symptoms. Digital rectal examination revealed an irregular and hard prostate. Flexible cystoscopy showed bladder base infiltration by the enlarged prostate obscuring both ureteric orifices, necessitating nephrostomy and subsequent bilateral antegrade stenting to relieve the obstruction and improve his renal function. Transrectal ultrasonography biopsy of the prostate was performed revealing histological features of SRCC. Due to its rarity, there is currently no standardized treatment approach and it is often similarly treated according to the traditional management of prostate adenocarcinoma.

Conclusions

SRCC of the prostate is a rare and aggressive subtype of acinar adenocarcinoma with no established guidelines. Histological criteria for SRCC of the prostate are highly variable in the available literature. It is important to differentiate between the primary and metastatic SRCC of the prostate as both are managed differently. However, the overall prognosis remains poor in general.

Development and validation of a quantitative reactive stroma biomarker (qRS) for prostate cancer prognosis

To develop and validate a new tissue-based biomarker that improves prediction of outcomes in localized prostate cancer by quantifying the host response to tumor. We use digital image analysis and machine learning to develop a biomarker of the prostate stroma called quantitative reactive stroma (qRS). qRS is a measure of percentage tumor area with a distinct, reactive stromal architecture. Kaplan Meier analysis was used to determine survival in a large retrospective cohort of radical prostatectomy samples. qRS was validated in two additional, distinct cohorts that include international cases and tissue from both radical prostatectomy and biopsy specimens. In the developmental cohort (Baylor College of Medicine, n = 482), patients whose tumor had qRS > 34% had increased risk of prostate cancer-specific death (HR 2.94; p = 0.039). This result was replicated in two validation cohorts, where patients with qRS > 34% had increased risk of prostate cancer-specific death (MEDVAMC; n = 332; HR 2.64; p = 0.02) and also biochemical recurrence (Canary; n = 988; HR 1.51; p = 0.001). By multivariate analysis, these associations were shown to hold independent predictive value when compared to currently used clinicopathologic factors including Gleason score and PSA. qRS is a new, validated biomarker that predicts prostate cancer death and biochemical recurrence across three distinct cohorts. It measures host-response rather than tumor-based characteristics, and provides information not represented by standard prognostic measurements.

Prostate Pathology: What is New in the 2022 WHO Classification of Urinary and Male Genital Tumors?

In 2022, after a six-year interval, the International Agency for Research on Cancer (IARC) has published the 5th edition of the WHO Classification of Urinary and Male Genital Tumors, which provides a comprehensive update on tumor classification of the genitourinary system. This review article focuses on prostate carcinoma and underscores changes in the prostate chapter as well as those made across the entire series of the 5th edition of WHO Blue Books. Although no major alterations were made to this chapter, some of the most notable updates include restructure of contents and introduction of a new format; standardization of mitotic counts, genomic nomenclatures, and units of length; refined definition for the terms "variant", "subtype", and "histologic pattern"; reclassification of prostatic intraepithelial neoplasia (PIN)-like adenocarcinoma as a subtype of prostatic acinar adenocarcinoma; and recognition of treatment-related neuroendocrine prostatic carcinoma as a distinct tumor type. Evolving and unsettled issues related to grading of intraductal carcinoma of the prostate and reporting of tertiary Gleason pattern, the definition and prognostic significance of cribriform growth pattern, and molecular pathology of prostate cancer will also be covered in this review.

Metabolic Phenotyping in Prostate Cancer Using Multi-Omics Approaches

Prostate cancer (PCa), one of the most frequently diagnosed cancers among men worldwide, is characterized by a diverse biological heterogeneity. It is well known that PCa cells rewire their cellular metabolism to meet the higher demands required for survival, proliferation, and invasion. In this context, a deeper understanding of metabolic reprogramming, an emerging hallmark of cancer, could provide novel opportunities for cancer diagnosis, prognosis, and treatment. In this setting, multi-omics data integration approaches, including genomics, epigenomics, transcriptomics, proteomics, lipidomics, and metabolomics, could offer unprecedented opportunities for uncovering the molecular changes underlying metabolic rewiring in complex diseases, such as PCa. Recent studies, focused on the integrated analysis of multi-omics data derived from PCa patients, have in fact revealed new insights into specific metabolic reprogramming events and vulnerabilities that have the potential to better guide therapy and improve outcomes for patients. This review aims to provide an up-to-date summary of multi-omics studies focused on the characterization of the metabolomic phenotype of PCa, as well as an in-depth analysis of the correlation between changes identified in the multi-omics studies and the metabolic profile of PCa tumors.

Molecular risk classifier score and biochemical recurrence risk are associated with cribriform pattern type in Gleason 3+4=7 prostate cancer

PURPOSE

Among Gleason pattern 4 types, cribriform pattern is associated with the worst outcomes. We hypothesized that larger cribriform patterns would be associated with increased Decipher scores and higher biochemical recurrence (BCR) risk in Gleason 3+4=7 prostatectomy patients.

MATERIALS AND METHODS

The slide from patients who underwent prostatectomy from January 2016 to March 2020 on which Decipher was performed was re-reviewed for Gleason score and cribriform patterns, with large cribriform defined as cribriform acini with greater than 12 lumens and simple cribriform as 12 or fewer lumens. Differences in Decipher score were analyzed in a generalized linear model controlling for pathology stage and tumor margin status. A multivariable Cox proportional hazards model was performed for BCR-free survival.

RESULTS

Of 337 cases, 118 were Gleason 3+4=7. The mean Decipher scores in 3+4=7 cases without cribriform, with simple cribriform, and with large cribriform were 0.41, 0.54, and 0.62, respectively. In a multivariable model with pathology stage, margin tumor length, and percentage pattern 4 as covariates, compared to cases without cribriform, simple cribriform was associated with 0.10 increase in Decipher (p=0.03) and 4.7-fold hazard ratio of BCR (95% confidence interval [CI], 0.4-56.5; p=0.22) and large cribriform was associated with 0.17 increase in Decipher (p<0.001) and 16.0-fold hazard ratio of BCR (95% CI, 1.4-181.2; p=0.02).

CONCLUSIONS

Among Gleason 3+4=7 carcinomas, large cribriform was associated with higher Decipher scores and greater BCR risk. Our results support that large cribriform is an aggressive pattern 4 subtype and should be considered a contraindication for active surveillance.

Hidden clues in prostate cancer - Lessons learned from clinical and pre-clinical approaches on diagnosis and risk stratification

The heterogeneity of prostate cancer is evident at clinical, morphological and molecular levels. To aid clinical decision making, a three-tiered system for risk stratification is used to designate low-, intermediate-, and high-risk of disease progression. Intermediate-risk prostate cancers are the most frequently diagnosed, and even with common diagnostic features, can exhibit vastly different clinical progression. Thus, improved risk stratification methods are needed to better predict patient outcomes. Here, we provide an overview of the improvements in diagnosis/prognosis arising from advances in pathology reporting of prostate cancer, which can improve risk stratification, especially for patients with intermediate-risk disease. This review discusses updates to pathology reporting of morphological growth patterns, and proposes the utility of integrating prognostic biomarkers or innovative imaging techniques to enhance clinical decision-making. To complement clinical studies, experimental approaches using patient-derived tumors have highlighted important cellular and morphological features associated with aggressive disease that may impact treatment response. The intersection of urology, pathology and scientific disciplines is required to work towards a common goal of understanding disease pathogenesis, improving the stratification of patients with intermediate-risk disease and subsequently defining optimal treatment strategies using precision-based approaches.

PTEN expression and morphological patterns in prostatic adenocarcinoma

AIMS

Cribriform morphology, which includes intraductal carcinoma (IDCP) and invasive cribriform carcinoma, is an indicator of poor prognosis in prostate cancer. Phosphatase and tensin homologue (PTEN) loss is a predictor of adverse clinical outcomes. The association between PTEN expression and morphological patterns of prostate cancer is unclear.

METHODS AND RESULTS

We explored the association between PTEN expression by immunohistochemistry, Gleason pattern 4 morphologies, IDCP and biochemical recurrence (BCR) in 163 radical prostatectomy specimens. IDCP was delineated from invasive cribriform carcinoma by p63 positive immunohistochemical staining in basal cells. Combined invasive cribriform carcinoma and IDCP were associated with a higher cumulative incidence of BCR [hazard ratio (HR) = 5.06; 2.21, 11.6, P < 0.001]. When including PTEN loss in the analysis, invasive cribriform carcinoma remained predictive of BCR (HR = 3.72; 1.75, 7.94, P = 0.001), while PTEN loss within invasive cribriform carcinoma did not. Glomeruloid morphology was associated with lower odds of cancer stage pT3 and lower cumulative incidence of BCR (HR = 0.27; 0.088, 0.796, P = 0.018), while PTEN loss within glomeruloid morphology was associated with a higher cumulative incidence of BCR (HR = 4.07; 1.04, 15.9, P = 0.043).

CONCLUSIONS

PTEN loss within glomeruloid pattern was associated with BCR. The presence of any cribriform pattern was associated with BCR, despite PTEN loss not significantly associated with invasive cribriform carcinoma. We speculate that other drivers independent from PTEN loss may contribute to poor prognostic features in cribriform carcinoma.

Multi-Dimensional Scaling Analysis of Key Regulatory Genes in Prostate Cancer Using the TCGA Database

Prostate cancer (PC) is a polygenic disease with multiple gene interactions. Therefore, a detailed analysis of its epidemiology and evaluation of risk factors can help to identify more accurate predictors of aggressive disease. We used the transcriptome data from a cohort of 243 patients from the Cancer Genome Atlas (TCGA) database. Key regulatory genes involved in proliferation activity, in the regulation of stress, and in the regulation of inflammation processes of the tumor microenvironment were selected to test a priori multi-dimensional scaling (MDS) models and create a combined score to better predict the patients' survival and disease-free intervals. Survival was positively correlated with cortisol expression and negatively with Mini-Chromosome Maintenance 7 (MCM7) and Breast-Related Cancer Antigen2 (BRCA2) expression. The disease-free interval was negatively related to the expression of enhancer of zeste homolog 2 (EZH2), MCM7, BRCA2, and programmed cell death 1 ligand 1 (PD-L1). MDS suggested two separate pathways of activation in PC. Within these two dimensions three separate clusters emerged: (1) cortisol and brain-derived neurotrophic factor BDNF, (2) PD-L1 and cytotoxic-T-lymphocyte-associated protein 4 (CTL4); (3) and finally EZH2, MCM7, BRCA2, and c-Myc. We entered the three clusters of association shown in the MDS in several Kaplan-Meier analyses. It was found that only Cluster 3 was significantly related to the interval-disease free, indicating that patients with an overall higher activity of regulatory genes of proliferation and DNA repair had a lower probability to have a longer disease-free time. In conclusion, our data study provided initial evidence that selecting patients with a high grade of proliferation and DNA repair activity could lead to an early identification of an aggressive PC with a potentials for metastatic development.

ISUP Consensus Definition of Cribriform Pattern Prostate Cancer

The presence of a cribriform pattern is now recognized as a clinically important, independent adverse prognostic indicator for prostate cancer. For this reason the International Society of Urological Pathology (ISUP) recently recommended its inclusion in standard reporting. In order to improve interobserver agreement as to the diagnosis of cribriform patterns, the ISUP assembled an international panel of 12 expert urogenital pathologists for the purpose of drafting a consensus definition of cribriform pattern in prostate cancer, and provide their opinions on a set of 32 images and on potential diagnostic criteria. These images were selected by the 2 nonvoting convenors of the study and included the main categories where disagreement was anticipated. The Delphi method was applied to promote consensus among the 12 panelists in their review of the images during 2 initial rounds of the study. Following a virtual meeting, convened to discuss selected images and diagnostic criteria, the following definition for cribriform pattern in prostate cancer was approved: "A confluent sheet of contiguous malignant epithelial cells with multiple glandular lumina that are easily visible at low power (objective magnification ×10). There should be no intervening stroma or mucin separating individual or fused glandular structures" together with a set of explanatory notes. We believe this consensus definition to be practical and that it will facilitate reproducible recognition and reporting of this clinically important pattern commonly seen in prostate cancer. The images and the results of the final Delphi round are available at the ISUP website as an educational slide set (https://isupweb.org/isup/blog/slideshow/cribriform-slide-deck/).

High expression of SCHLAP1 in primary prostate cancer is an independent predictor of biochemical recurrence, despite substantial heterogeneity

In primary prostate cancer, the common multifocality and heterogeneity are major obstacles in finding robust prognostic tissue biomarkers. The long noncoding RNA SCHLAP1 has been suggested, but its prognostic value has not been investigated in the context of tumor heterogeneity. In the present study, expression of SCHLAP1 was investigated using real-time RT-PCR in a multisampled series of 778 tissue samples from radical prostatectomies of 164 prostate cancer patients (median follow-up time 7.4 y). The prognostic value of SCHLAP1 was evaluated with biochemical recurrence as endpoint. In total, 29% of patients were classified as having high expression of SCHLAP1 in at least one malignant sample. Among these, inter- and intrafocal heterogeneity was detected in 72% and 56%, respectively. High expression of SCHLAP1 was shown to be a predictor of biochemical recurrence in both uni- and multivariable cox regression analyses (P < 0.001 and P = 0.02). High expression of SCHLAP1 was also significantly associated with adverse clinicopathological characteristics, including grade group, high pT stage, invasive cribriform growth/intraductal carcinoma of the prostate, and reactive stroma. In conclusion, high expression of SCHLAP1 in at least one malignant sample is a robust prognostic biomarker in primary prostate cancer. For the first time, high SCHLAP1 expression has been associated with the aggressive histopathologic feature reactive stroma. The expression of SCHLAP1 is highly heterogeneous, and analysis of multiple samples is therefore crucial in determination of the SCHLAP1 status of a patient.

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.

Assessment of MYC/PTEN Status by Gene-Protein Assay in Grade Group 2 Prostate Biopsies

This study leveraged a gene-protein assay to assess MYC and PTEN status at prostate cancer biopsy and examined the association with adverse outcomes after surgery. MYC gain and PTEN loss were simultaneously assessed by chromogenic in situ hybridization and immunohistochemistry, respectively, using 277 Grade Group 2 needle biopsies that were followed by prostatectomy. The maximal size of cribriform Gleason pattern 4 carcinoma (CRIB), the presence of intraductal carcinoma (IDC), and percentage of Gleason pattern 4 carcinoma at biopsy were also annotated. MYC gain or PTEN loss was present in 19% and 18% of biopsies, respectively, whereas both alterations were present in 9% of biopsies. Tumors with one or both alterations were significantly more likely to have non-organ-confined disease (NOCD) at radical prostatectomy. In logistic regression models, including clinical stage, tumor volume on biopsy, and presence of CRIB/IDC, cases with MYC gain and PTEN loss remained at higher risk for NOCD (odds ratio, 6.23; 95% CI, 1.74-24.55; P = 0.005). The area under the curve for a baseline model using CAPRA variables (age, prostate-specific antigen, percentage of core involvement, clinical stage) was increased from 0.68 to 0.69 with inclusion of CRIB/IDC status and to 0.75 with MYC/PTEN status. Dual MYC/PTEN status can be assessed in a single slide and is independently associated with increased risk of NOCD for Grade Group 2 biopsies.

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.

A distinct repertoire of cancer-associated fibroblasts is enriched in cribriform prostate cancer

Outcomes for men with localized prostate cancer vary widely, with some men effectively managed without treatment on active surveillance, while other men rapidly progress to metastatic disease despite curative-intent therapies. One of the strongest prognostic indicators of outcome is grade groups based on the Gleason grading system. Gleason grade 4 prostate cancer with cribriform morphology is associated with adverse outcomes and can be utilized clinically to improve risk stratification. The underpinnings of disease aggressiveness associated with cribriform architecture are not fully understood. Most studies have focused on genetic and molecular alterations in cribriform tumor cells; however, less is known about the tumor microenvironment in cribriform prostate cancer. Cancer-associated fibroblasts (CAFs) are a heterogeneous population of fibroblasts in the tumor microenvironment that impact cancer aggressiveness. The overall goal of this study was to determine if cribriform prostate cancers are associated with a unique repertoire of CAFs. Radical prostatectomy whole-tissue sections were analyzed for the expression of fibroblast markers (ASPN in combination with FAP, THY1, ENG, NT5E, TNC, and PDGFRβ) in stroma adjacent to benign glands and in Gleason grade 3, Gleason grade 4 cribriform, and Gleason grade 4 noncribriform prostate cancer by RNAscope®. Halo® Software was used to quantify percent positive stromal cells and expression per positive cell. The fibroblast subtypes enriched in prostate cancer were highly heterogeneous. Both overlapping and distinct populations of low abundant fibroblast subtypes in benign prostate stroma were enriched in Gleason grade 4 prostate cancer with cribriform morphology compared to Gleason grade 4 prostate cancer with noncribriform morphology and Gleason grade 3 prostate cancer. In addition, gene expression was distinctly altered in CAF subtypes adjacent to cribriform prostate cancer. Overall, these studies suggest that cribriform prostate cancer has a unique tumor microenvironment that may distinguish it from other Gleason grade 4 morphologies and lower Gleason grades.

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.

Inter- and intra-tumor heterogeneity of metastatic prostate cancer determined by digital spatial gene expression profiling

Metastatic prostate cancer (mPC) comprises a spectrum of diverse phenotypes. However, the extent of inter- and intra-tumor heterogeneity is not established. Here we use digital spatial profiling (DSP) technology to quantitate transcript and protein abundance in spatially-distinct regions of mPCs. By assessing multiple discrete areas across multiple metastases, we find a high level of intra-patient homogeneity with respect to tumor phenotype. However, there are notable exceptions including tumors comprised of regions with high and low androgen receptor (AR) and neuroendocrine activity. While the vast majority of metastases examined are devoid of significant inflammatory infiltrates and lack PD1, PD-L1 and CTLA4, the B7-H3/CD276 immune checkpoint protein is highly expressed, particularly in mPCs with high AR activity. Our results demonstrate the utility of DSP for accurately classifying tumor phenotype, assessing tumor heterogeneity, and identifying aspects of tumor biology involving the immunological composition of metastases.

The inter- and intra-tumor heterogeneity of metastatic prostate cancer (mPC) is underexplored. Here the authors use Digital Spatial Profiling to study gene and protein expression heterogeneity in 27 mPC patients, finding variation in associated pathways and potential immunotherapy targets.

GPS Assay Association With Long-Term Cancer Outcomes: Twenty-Year Risk of Distant Metastasis and Prostate Cancer-Specific Mortality

PURPOSE

To assess the association between the Oncotype DX Genomic Prostate Score (GPS) result and long-term oncological outcomes following radical prostatectomy (RP).

METHODS

We evaluated the association of the GPS result assayed from the index lesion from RP tissue with the risk of distant metastases (DM) and prostate cancer–specific mortality (PCSM) over the 20 years following RP in a stratified cohort sample of 428 patients from 2,641 treated between 1987 and 2004. Cox regression of cause-specific hazards was used to estimate the absolute risk of both end points, with death from other causes treated as a competing risk. A correction for regression to the mean (RM) was applied since the GPS test was developed using this cohort. Exploratory analysis using presurgical parameters and the GPS test as prognostic variables was performed to assess the additional value of the GPS test on 20-year risk of DM and PCSM. Model discrimination was measured using the area under the receiver operating characteristic curve.

RESULTS

The GPS test appears to be independently associated with both 20-year risk of DM and PCSM with a low false discovery rate. Per 20-unit increase in GPS, multivariable analysis with RM correction estimated hazard ratios of 2.24 (95% CI, 1.49 to 3.53) and 2.30 (95% CI, 1.45 to 4.36) for DM and PCSM, respectively. Accuracy of models including clinical risk factors alone appeared to improve when including the GPS test in assessing risk of both end points.

CONCLUSION

The results suggest that the GPS test provides information on the risk for the meaningful long-term outcomes of DM and PCSM.

Unsupervised Tumor Characterization via Conditional Generative Adversarial Networks

Grading for cancer, based upon the degree of cancer differentiation, plays a major role in describing the characteristics and behavior of the cancer and determining treatment plan for patients. The grade is determined by a subjective and qualitative assessment of tissues under microscope, which suffers from high inter- and intra-observer variability among pathologists. Digital pathology offers an alternative means to automate the procedure as well as to improve the accuracy and robustness of cancer grading. However, most of such methods tend to mimic or reproduce cancer grade determined by human experts. Herein, we propose an alternative, quantitative means of assessing and characterizing cancers in an unsupervised manner. The proposed method utilizes conditional generative adversarial networks to characterize tissues. The proposed method is evaluated using whole slide images (WSIs) and tissue microarrays (TMAs) of colorectal cancer specimens. The results suggest that the proposed method holds a potential for quantifying cancer characteristics and improving cancer pathology.

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.

Analysis of Serum Markers with Regard to Treatment Procedures in Advanced Stage Prostate Cancer Patients

Background

Biomarkers predicting the efficacy of treatment for locally limited prostate cancer are greatly needed. This knowledge could improve the classification of patients for different methods of treatment and enable better recognition of groups with higher risk of biological recurrence. We prospectively assessed serial blood levels of apoptotic biomarkers and correlated them with response to treatment and clinical factors.

Material/Methods

Blood was collected from 25 patients with prostate cancer before and after surgery, 16 healthy volunteers with benign prostatic hyperplasia (BPH), and 14 patients with metastasized disease. Immunoenzymatic methods were used to determine circulating apoptotic and inflammatory mediators, including tumor necrosis factor α (TNF-α), type I receptor (TNFRI), and type II receptor (TNFRII); FAS ligand (FasL); TNF-related apoptosis-inducing ligand (TRIAL); caspase 8 (Cas8); caspase 9 (Cas9); DNA methylation (metDNA); P-selectin; and high-sensitivity C-reactive protein. The total circulating fragments of cell-free DNA (cfDNA) were measured directly in serum.

Results

Peripheral serum prostate-specific antigen increased rapidly together with cfDNA. A negative correlation was noted between tumor volume and TNFRI and TNFRII. Postsurgery P-selectin level was decreased, and metDNA and TNFRII levels were increased. Three comparisons were made between patient groups: surgical vs. BPH; surgical vs. palliative; and palliative vs. BPH. TNFRI, TNFRII, metDNA, P-selectin, Cas8, and FasL were shown to have significant roles.

Conclusions

The study indicated significant roles for cfDNA, both TNF receptors, metDNA, and P-selectin as serum biomarkers in patients with prostate cancer.

The Impact of Histopathological Features of Prostate Cancerous Lesions on Multiparametric Magnetic Resonance Imaging Findings using PI-RADS Version 2

OBJECTIVES

To determine the square measure threshold of prostate cancer lesions in pathological specimens showing PI-RADS categories 3 to 5, and to identify the pathological characteristics of cancerous lesions over the threshold.

METHODS

Cancer foci detected in horizontal sections of specimens were defined as pathological cancerous lesions, in which square measure, lesion location (peripheral or transition zone), Gleason pattern (GP), GP4-5 component percentages, and GP 4 subtypes were assessed. A receiver operating characteristic curve was used to determine the threshold of the square measure of pathological specimens that distinguishes between lesions of PI-RADS categories 1 and 2 and those of 3 to 5. Univariable and multivariable analyses were performed to determine the histopathological features associated with PI-RADS categories 3 to 5.

RESULTS

A total of 100 consecutive patients underwent multiparametric magnetic resonance imaging before robotic-assisted laparoscopic prostatectomy. A total of 1366 pathological cancerous lesions were detected, 217 of which were classified as PI-RADS categories 3 to 5. A square measure of 40 mm² on pathological specimens was the threshold for PI-RADS categories 3 to 5. Of the 415 lesions that were over 40 mm², 211 lesions exhibited PI-RADS categories 1, 2 and 204 lesions exhibited PI-RADS categories 3 to 5. Multiple logistic regression analysis showed that square measure, fused glands, and cribriform glands were independently associated with PI-RADS categories 3 to 5.

CONCLUSION

Cancerous lesions over 40 mm² showing PI-RADS categories 3 to 5 are associated with square measure, fused glands, and cribriform glands.

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.

Current experimental human tissue-derived models for prostate cancer research

Scientists engaged in prostate cancer research have been conducting experiments using two-dimensional cultures of prostate cancer cell lines for decades. However, these experiments fail to reproduce and reflect the clinical course of individual patients with prostate cancer, or the molecular and genetic characteristics of prostate cancer, the basic requirement for most of the preclinical studies on prostate cancer. The use of human prostate cancer tissues in experiments has enabled the collection and verification of clinically relevant data, including chemical reactions, changes in proteins, and specific gene expression. Tissue recombination models have been employed for studying prostate development, the initiation and progression of prostate cancer, and the tumor microenvironment. Notably, the epithelial-stromal interaction, which might play a critical role in prostate cancer pathogenesis, can be reproduced in this model. Patient-derived xenograft models have been developed as powerful avatars comprising patient-derived prostate cancer tissues implanted in immunocompromised mice and could serve as a precision medicine approach for each prostate cancer patient. Spheroid and organoid assays, representative of modern three-dimensional cultures, can replicate the conditions in human prostate tumors and the prostate organ itself as a miniature model. Although an intact immune system against the tumor is missing from the models aimed at investigating immuno-oncological reagents in various malignancies, all these experimental models can help researchers in developing new drugs and selecting appropriate treatment strategies for prostate cancer patients.

Cribriform pattern does not have a significant impact in Gleason Score ≥7/ISUP Grade ≥2 prostate cancers submitted to radical prostatectomy

INTRODUCTION

The aim of this study was to correlate cribriform pattern (CP) with other parameters in a large prospective series of Gleason score ≥7/ISUP grade ≥2 prostate cancer (PC) cases undergoing radical prostatectomy (RP).

METHODS

This is a prospective single-center study on 210 consecutive patients. Gleason pattern 4 and individual tumor growth patterns determination were performed either in biopsy or in surgical specimens for all patients.

RESULTS

At multiparametric magnetic resonance, a higher percentage of PI-RADS 5 was associated to CP (53.3% vs 17.7%, P = .038). CP was significantly and inversely (r = -0.261; P = .001) correlated with perineural invasion (PNI) but not with other pathological parameters. Kaplan-Meier analysis showed that mean biochemical (Bp) and radiological (Rp) progression-free survival were similar (Bp = χ 0.906; P = .341; Rp = χ 1.880; P = .170) independently to CP. In PNI positive cases, Bp-free survival was higher (χ = 3.617; P = .057) in cases without CP.

CONCLUSIONS

In a homogeneous population excluding ISUP 1 cases, CP showed limited prognostic value. We first described an association with PNI and a prognostic value influenced by PNI status.

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.

Diagnostic performance of a nomogram incorporating cribriform morphology for the prediction of adverse pathology in prostate cancer at radical prostatectomy

The aim of the present study was to develop a novel nomogram that incorporated clinical factors, imaging parameters and biopsy pathological factors (including cribriform morphology) to predict adverse pathology in prostate cancer (PCa). A total of 223 patients with PCa, who had undergone preoperative multi-parametric magnetic resonance imaging and had a biopsy of Gleason pattern (GP) 4, absence of GP 5 and pure Grade Group (GG) 3 [Gleason score (GS) 3+4, GS 4+3, GS 4+4], were retrospectively enrolled onto the study. The contribution of GG to the biopsy and Prostate Imaging Reporting and Data System (PI-RADS) score for PCa harboring adverse pathology were analyzed. Univariate and multivariate logistic regression analyses were performed to determine significant pathology predictors of adverse pathology for nomogram development. The nomogram was internally validated using bootstrapping with 1,000 iterations. The diagnostic performance of the nomogram was analyzed by receiver operating characteristics (ROC) analysis and decision curve analysis (DCA). A higher biopsy GG and PI-RADS score were associated with an increased likelihood of adverse pathology. Prostate specific antigen density (PSAD), biopsy GG, cribriform morphology on biopsy and PI-RADS score were significant predictors and were included in the nomogram. The ROC area under the curve of the nomogram was 0.88 (95% confidence interval, 0.84-0.91), with a high specificity (0.91) and moderate sensitivity (0.72). The novel nomogram was shown to have a higher net benefit for the prediction of adverse pathology in PCa, compared with any individual factors determined by DCA. Overall, a novel nomogram incorporating PSAD, PI-RADS score, biopsy GG and cribriform morphology on biopsy was shown to perform well in the prediction of PCa harboring adverse pathology at the time of radical prostatectomy.

Stromal reactivity differentially drives tumour cell evolution and prostate cancer progression

Prostate cancer (PCa) progression is a complex eco-evolutionary process driven by the feedback between evolving tumour cell phenotypes and microenvironmentally driven selection. To better understand this relationship, we used a multiscale mathematical model that integrates data from biology and pathology on the microenvironmental regulation of PCa cell behaviour. Our data indicate that the interactions between tumour cells and their environment shape the evolutionary dynamics of PCa cells and explain overall tumour aggressiveness. A key environmental determinant of this aggressiveness is the stromal ecology, which can be either inhibitory, highly reactive (supportive) or non-reactive (neutral). Our results show that stromal ecology correlates directly with tumour growth but inversely modulates tumour evolution. This suggests that aggressive, environmentally independent PCa may be a result of poor stromal ecology, supporting the concept that purely tumour epithelium-centric metrics of aggressiveness may be incomplete and that incorporating markers of stromal ecology would improve prognosis.