International Society of Urological Pathology (ISUP) Consensus Conference on Current Issues in Bladder Cancer: Working Group 3: Subcategorization of T1 Bladder Cancer.

Emerging data on T1 bladder cancer subcategorization (aka substaging) suggests a correlation with oncological outcomes. The International Society of Urological Pathology (ISUP) organized the 2022 consensus conference in Basel, Switzerland to focus on current issues in bladder cancer and tasked working group 3 to make recommendations for T1 subcategorization in transurethral bladder resections. For this purpose, the ISUP developed and circulated a survey to their membership querying approaches to T1 bladder cancer subcategorization. In particular, clinical relevance, pathological reporting, and endorsement of T1 subcategorization in the daily practice of pathology were surveyed. Of the respondents of the premeeting survey, about 40% do not routinely report T1 subcategory. We reviewed literature on bladder T1 subcategorization, and screened selected articles for clinical performance and practicality of T1 subcategorization methods. Published literature offered evidence of the clinical rationale for T1 subcategorization and at the conference consensus (83% of conference attendants) was obtained to report routinely T1 subcategorization of transurethral resections. Semiquantitative T1 subcategorization was favored (37%) over histoanatomic methods (4%). This is in line with literature findings on practicality and prognostic impact, that is, a shift of publications from histoanatomic to semiquantitative methods or by reports incorporating both methodologies is apparent over the last decade. However, 59% of participants had no preference for either methodology. They would add a comment in the report briefly stating applied method, interpretation criteria (including cutoff), and potential limitations. When queried on the terminology of T1 subcategorization, 34% and 20% of participants were in favor of T1 (microinvasive) versus T1 (extensive) or T1 (focal) versus T1 (nonfocal), respectively.

Prostate Adenocarcinoma Grade Group 1: Rationale for Retaining a Cancer Label in the 2022 World Health Organization Classification.

We present the rationale for keeping the "cancer" label for grade group 1 (GG1) prostate cancer. Maintaining GG1 as the lowest grade outweighs the potential benefits that a benign designation may bring. Patient and surgeon education on the vital role of active surveillance for GG1 cancers and avoidance of overtreatment should be the focus rather than such a drastic change in nomenclature.

Data Set for the Reporting of Endometrial Cancer: Recommendations From the International Collaboration on Cancer Reporting (ICCR).

Endometrial cancer is one of the most common cancers among women. The International Collaboration on Cancer Reporting (ICCR) developed a standardized endometrial cancer data set in 2011, which provided detailed recommendations for the reporting of resection specimens of these neoplasms. A new data set has been developed, which incorporates the updated 2020 World Health Organization Classification of Female Genital Tumors, the Cancer Genome Atlas (TCGA) molecular classification of endometrial cancers, and other major advances in endometrial cancer reporting, all of which necessitated a major revision of the data set. This updated data set has been produced by a panel of expert pathologists and an expert clinician and has been subject to international open consultation. The data set includes core elements which are unanimously agreed upon as essential for cancer diagnosis, clinical management, staging, or prognosis and noncore elements which are clinically important, but not essential. Explanatory notes are provided for each element. Adoption of this updated data set will result in improvements in endometrial cancer patient care.

The 2022 World Health Organization Classification of Tumors of the Urinary System and Male Genital Organs-Part B: Prostate and Urinary Tract Tumors.

The 2022 World Health Organization (WHO) classification of the urinary and male genital tumors was recently published by the International Agency for Research on Cancer. This fifth edition of the WHO "Blue Book" offers a comprehensive update on the terminology, epidemiology, pathogenesis, histopathology, diagnostic molecular pathology, and prognostic and predictive progress in genitourinary tumors. In this review, the editors of the fifth series volume on urologic and male genital neoplasms present a summary of the salient changes introduced to the classification of tumors of the prostate and the urinary tract.

The 2022 World Health Organization Classification of Tumours of the Urinary System and Male Genital Organs-Part A: Renal, Penile, and Testicular Tumours.

The fifth edition of the World Health Organization (WHO) classification of urogenital tumours (WHO "Blue Book"), published in 2022, contains significant revisions. This review summarises the most relevant changes for renal, penile, and testicular tumours. In keeping with other volumes in the fifth edition series, the WHO classification of urogenital tumours follows a hierarchical classification and lists tumours by site, category, family, and type. The section "essential and desirable diagnostic criteria" included in the WHO fifth edition represents morphologic diagnostic criteria, combined with immunohistochemistry and relevant molecular tests. The global introduction of massive parallel sequencing will result in a diagnostic shift from morphology to molecular analyses. Therefore, a molecular-driven renal tumour classification has been introduced, taking recent discoveries in renal tumour genomics into account. Such novel molecularly defined epithelial renal tumours include SMARCB1-deficient medullary renal cell carcinoma (RCC), TFEB-altered RCC, Alk-rearranged RCC, and ELOC-mutated RCC. Eosinophilic solid and cystic RCC is a novel morphologically defined RCC entity. The diverse morphologic patterns of penile squamous cell carcinomas are grouped as human papillomavirus (HPV) associated and HPV independent, and there is an attempt to simplify the morphologic classification. A new chapter with tumours of the scrotum has been introduced. The main nomenclature of testicular tumours is retained, including the use of the term "germ cell neoplasia in situ" (GCNIS) for the preneoplastic lesion of most germ cell tumours and division from those not derived from GCNIS. Nomenclature changes include replacement of the term "primitive neuroectodermal tumour" by "embryonic neuroectodermal tumour" to separate these tumours clearly from Ewing sarcoma. The term "carcinoid" has been changed to "neuroendocrine tumour", with most examples in the testis now classified as "prepubertal type testicular neuroendocrine tumour".

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.

An introduction to the WHO 5th edition 2022 classification of testicular tumours.

The 5th edition of the World Health Organisation Blue Book was published recently and includes a comprehensive update on testicular tumours. This builds upon the work of the 4th edition, retaining its structure and main nomenclature, including the use of the term 'germ cell neoplasia in situ' (GCNIS) for the pre-invasive lesion of most germ cell tumours and division from those not derived from GCNIS. While there have been important developments in understanding the molecular underpinnings of testicular cancer, this updated classification paradigm and approach remains rooted in morphology. Nomenclature changes include replacement of the term 'primitive neuroectodermal tumour' by 'embryonic neuroectodermal tumour' based on the non-specificity of the former term and to separate these tumours clearly from Ewing sarcoma. Seminoma is placed in a germinoma family of tumours emphasising relation to those tumours at other sites. Criteria for the diagnosis of 'teratoma with somatic transformation' have been modified to not include variable field size assessments. The word 'carcinoid' has been changed to 'neuroendocrine tumour', with most examples in the testis now classified as 'prepubertal type testicular neuroendocrine tumour'. For sex cord-stromal tumours, the use of mitotic counts per high-power field has been changed to per mm2 for malignancy assessments, and the new entities, 'signet ring stromal tumour' and 'myoid gonadal stromal tumour', are defined. Well-differentiated papillary mesothelial tumour has now been defined as tumour type with a favourable prognosis. Sertoliform cystadenoma has been removed as an entity from testicular adnexal tumours and placed with Sertoli cell tumours.

WHO 2022 landscape of papillary and chromophobe renal cell carcinoma.

The 5th edition of the WHO Classification of Tumours of the Urinary and Male Genital Systems contains relevant revisions and introduces a group of molecularly defined renal tumour subtypes. Herein we present the World Health Organization (WHO) 2022 perspectives on papillary and chromophobe renal cell carcinoma with emphasis on their evolving classification, differential diagnosis, and emerging entities. The WHO 2022 classification eliminated the type 1/2 papillary renal cell carcinoma (pRCC) subcategorization, given the recognition of frequent mixed tumour phenotypes and the existence of entities with a different molecular background within the type 2 pRCC category. Additionally, emerging entities such as biphasic squamoid alveolar RCC, biphasic hyalinising psammomatous RCC, papillary renal neoplasm with reverse polarity, and Warthin-like pRCC are included as part of the pRCC spectrum, while additional morphological and molecular data are being gathered. In addition to oncocytomas and chromophobe renal cell carcinoma (chRCC), a category of 'other oncocytic tumours' with oncocytoma/chRCC-like features has been introduced, including emerging entities, most with TSC/mTOR pathway alterations (eosinophilic vacuolated tumour and so-called 'low-grade' oncocytic tumour), deserving additional research. Eosinophilic solid and cystic RCC was accepted as a new and independent tumour entity. Finally, a highly reproducible and clinically relevant universal grading system for chRCC is still missing and is another niche of ongoing investigation. This review discusses these developments and highlights emerging morphological and molecular data relevant for the classification of renal cell carcinoma.

The Genitourinary Pathology Society Update on Classification and Grading of Flat and Papillary Urothelial Neoplasia With New Reporting Recommendations and Approach to Lesions With Mixed and Early Patterns of Neoplasia.

The Genitourinary Pathology Society (GUPS) undertook a critical review of the recent advances in bladder neoplasia with a focus on issues relevant to the practicing surgical pathologist for the understanding and effective reporting of bladder cancer, emphasizing particularly on the newly accumulated evidence post-2016 World Health Organization (WHO) classification. The work is presented in 2 manuscripts. Here, in the first, we revisit the nomenclature and classification system used for grading flat and papillary urothelial lesions centering on clinical relevance, and on dilemmas related to application in routine reporting. As patients of noninvasive bladder cancer frequently undergo cystoscopy and biopsy in their typically prolonged clinical course and for surveillance of disease, we discuss morphologies presented in these scenarios which may not have readily applicable diagnostic terms in the WHO classification. The topic of inverted patterns in urothelial neoplasia, particularly when prominent or exclusive, and beyond inverted papilloma has not been addressed formally in the WHO classification. Herein we provide a through review and suggest guidelines for when and how to report such lesions. In promulgating these GUPS recommendations, we aim to provide clarity on the clinical application of these not so uncommon diagnostically challenging situations encountered in routine practice, while also importantly advocating consistent terminology which would inform future work.

The Genitourinary Pathology Society Update on Classification of Variant Histologies, T1 Substaging, Molecular Taxonomy, and Immunotherapy and PD-L1 Testing Implications of Urothelial Cancers.

The Genitourinary Pathology Society (GUPS) undertook a critical review of the recent advances in bladder cancer focusing on important topics of high interest for the practicing surgical pathologist and urologist. This review represents the second of 2 manuscripts ensuing from this effort. Herein, we address the effective reporting of bladder cancer, focusing particularly on newly published data since the last 2016 World Health Organization (WHO) classification. In addition, this review focuses on the importance of reporting bladder cancer with divergent differentiation and variant (subtypes of urothelial carcinoma) histologies and the potential impact on patient care. We provide new recommendations for reporting pT1 staging in diagnostic pathology. Furthermore, we explore molecular evolution and classification, emphasizing aspects that impact the understanding of important concepts relevant to reporting and management of patients.

Clinicopathologic analysis of upper urinary tract carcinoma with variant histology.

We report on the clinicopathologic features of 115 cases of high-grade urothelial carcinoma of the upper urinary tract with variant histology present in 39 (34%). Variant histology was typically seen in high pathological stage (pT2-pT4) (82%, 32 cases) patients with lower survival rate (70%, 27 cases, median survival 31 months) and consisted in urothelial with one (23%), two (3%), and three or more variants (3%); 4% of cases presented with pure variant histology. Squamous divergent differentiation was the most common variant (7%) followed by sarcomatoid (6%) and glandular (4%), followed by 3% each of micropapillary, diffuse-plasmacytoid, inverted growth, clear cell glycogenic, or lipid-rich. The pseudo-angiosarcomatous variant is seen in 2%, and 1% each of nested, giant-cell, lymphoepithelioma-like, small-cell, trophoblastic, rhabdoid, microcystic, lymphoid-rich stroma, or myxoid stroma/chordoid completed the study series. Loss of mismatch repair protein expression was identified in one case of upper urinary tract carcinoma with inverted growth variant (3.6%). Variant histology was associated to pathological stage (p = 0.007) and survival status (p = 0.039). The univariate survival analysis identified variant histology as a feature of lower recurrence-free survival (p = 0.046). Our findings suggest that variant histology is a feature of aggressiveness in urothelial carcinoma of the upper urinary tract worth it to be reported.

Current and emerging bladder cancer biomarkers with an emphasis on urine biomarkers.

Introduction: Bladder cancer detection typically requires unpleasant and costly cystoscopy, a procedure potentially harmful and often accompanied by variable adverse effects. The use of urine analysis as a noninvasive method is of great scientific interest since it is enriched in tumor-related proteins, DNA and RNA which can provide a molecular landscape with multiple alterations identified in bladder cancer.Areas covered: Current sensitivity, specificity and diagnostic accuracy of FDA approved urine-based assays are still suboptimal with none of them routinely used by clinics. The recent introduction of RNA/DNA based bladder cancer tests, some of them commercially available, establishes a promising new horizon of clinical applicability.Expert opinion: There is growing evidence toward the use of minimally invasive 'liquid biopsies' to identify biomarkers in urothelial malignancy. Urine has been identified as an optimal noninvasive source of proteins, DNA and RNA; therefore, it has been identified as a type of liquid biopsy likely to soon be routine clinical practice. Cell-free proteins and peptides, exosomes, cell-free DNA, methylated DNA and DNA mutations, circulating tumor cells, miRNA, lncRNA, rtRNA and mRNAs, have been assessed in urine specimens. However, lack of well-designed multicenter clinical studies remain as important limitation, and therefore, precludes their use in clinical practice.

Digital versus light microscopy assessment of extraprostatic extension in radical prostatectomy samples.

Focal or non-focal/extensive extraprostatic extension of prostate carcinoma is an important pathologic prognostic parameter to be reported after radical prostatectomy. Currently, there is no agreement on how to measure and what are the best cutoff points to be used in practice. We hypothesized that digital microscopy would potentially provide more objective measurements of extraprostatic extension, thus better defining its clinical significance. To further our knowledge on digital prostate pathology, we evaluated the status of extraprostatic extension in 107 consecutive laparoscopic radical prostatectomy samples, using digital and conventional light microscopy. Mean linear and radial measurements of extraprostatic extension by digital microscopy significantly correlated to pT status (p = 0.022 and p = 0.050, respectively) but only radial measurements correlated to biochemical recurrence (p = 0.042) and grade groups (p = 0.022). None of the measurements, whether conventional or digital, were associated with lymph node status. Receiving operating characteristic analysis showed a potential cutoff point to assess linear measurements by conventional (< vs. > 24.21 mm) or digital microscopy (< vs. > 15 mm) or by radial measurement (< vs. > 1.6 mm). Finally, we observed an association between the number of paraffin blocks bearing EPE with pT (p = 0.041) status (digital microscopy), and linear measurements by conventional (p = 0.044) or digital microscopy (p = 0.045) with lymph node status. Reporting EPE measurements by digital microscopy, both linear and radial, and the number of paraffin blocks with EPE, might provide additional prognostic features after radical prostatectomy.

Surgical management of a rare case of giant penile cancer.

Primary penile cancer is a rare malignant disease. In most cases, it presents as a clinically obvious lesion leading to early diagnosis in most patients. However, even in developed Countries, it carries a significant social stigma leading to diagnosis at locally advanced stages in a non-negligible proportion of patients. Yet, bulky penile lesions are becoming extremely rare in current clinical practice. We present a case of a patient with a giant primary penile cancer managed with radical penectomy, bilateral inguinal lymphadenectomy and perineal urethrostomy, who experienced disease recurrence six months after surgery and died with metastatic disease after denial of further treatment. The management of our case was challenging due to the extremely late diagnosis, the huge dimensions and the infiltrative nature of the tumor; however, from a histopathological perspective, the cancer itself did not display any microscopic peculiarity. Our case highlights that such bulky penile tumors can still occur in current urologic practice and require complex salvage surgical interventions in the context of a multidisciplinary setting.

Variants and new entities of bladder cancer.

Pathological evaluation of bladder cancer typically reveals great tumour heterogeneity, and therefore the common observation of urothelial carcinoma exhibiting a wide variety of histopathological patterns is not surprising. Some of these patterns are so distinctive that they have been recognised as specific variants of urothelial carcinoma. Classifications have recently been revised in the 2016 World Health Organisation (WHO) classification of tumours of the urinary system and male genital organs. The current WHO classifications clarify terminological issues and provide better definition criteria, but also incorporate some new entities. Many of these variants have important prognostic or therapeutic implications worth knowing by the urologist and oncologist, but also represent diagnostic challenges in daily pathology practice. This review will discuss the features of variants of urothelial carcinoma in the context of our current clinical practice. Histological variations and new entities of bladder cancer not included in the current WHO classification of urothelial tumours will be briefly discussed.

Iatrogenic pathology of the urinary bladder.

Intravesical immunotherapy, chemotherapy, and neoadjuvant systemic chemotherapy are among the most frequent therapeutic procedures to treat malignancies of the urinary bladder. These treatment modalities produce reactive morphologic changes in the urothelium that can mimic urothelial carcinoma in situ, urothelial dysplasia or true invasive urothelial neoplasia. Mitomycin C used after transurethral resection of bladder tumor to reduce recurrences, BCG intravesical immunotherapy to treat high risk non-muscle invasive bladder cancer and urothelial carcinoma in situ, and platinum-based systemic chemotherapy to improve post-cystectomy disease-specific survival some of the causes of therapy related atypia in urinary bladder. In addition, a number of systemic drugs in use to treat other systemic diseases, such as cyclophosphamide used to treat certain auto-immune disorders or hematologic malignancies, or the anesthetics ketamine increasingly used as illegal recreational drug, may produce similarly relevant atypical changes in the urothelium, and therefore, need to be differentiated from intraepithelial neoplasia. Immunohistochemical approach to reactive urothelium from CIS using CK20, p53, and CD44 may also be of utility in the pos-therapy scenario.

Digital versus light microscopy assessment of surgical margin status after radical prostatectomy.

Positive surgical margin (PSM) extension reported as focal or non-focal/extensive is an important pathologic prognostic parameter after radical prostatectomy. Likewise, there is limited or no agreement on how to measure and what the best cut-off points to be used in practice are. We hypothesized that digital microscopy (DM) would potentially provide a more objective way to measure PSM and better define its clinical significance. To further our knowledge, we have evaluated PSM status in 107 laparoscopic radical prostatectomies using digital and conventional light microscopy (LM). DM evaluation detected three additional PSM cases, but no differences were seen (LM vs DM; p = 0.220). Mean linear measurement correlated to biochemical recurrence (BR) (LM, p = 0.002; DM, p = 0.001). ROC analysis identified a cut-off point to assess linear measurement by LM (3.5 mm) or DM (3.2 mm), but only digital measurement was significant for BR-free survival. Our study also evaluated a cut-off ≤ 3 mm that was associated to BR using LM (p = 0.023) or DM (p = 0.001). Finally, the number of paraffin blocks bearing PSM correlated with BR (p < 0.001) status with either LM or DM. In conclusion, DM produces similar data than LM but shows more accurate measurements. Reporting of PSM with score of ≤ 3 vs. > 3 mm linear extent using LM (3.2 mm if digital microscopy is applied) might represent an important prognostic feature after radical prostatectomy. Alternatively, reporting the number of blocks with PSM 1 vs. 2 or more might also provide important prognostic data in practice.

Inherited forms of bladder cancer: a review of Lynch syndrome and other inherited conditions.

Environmental factors that play a role in the urothelial carcinogenesis have been well characterized. Current research is continuously exploring potential heritable forms of bladder cancer. Lynch syndrome is a well-known inheritable disease that increases the risk for a variety of cancers, including urothelial carcinomas. Screening of patients with known Lynch syndrome is important to evaluate for development of new primary tumors. Further study may provide more information on what level of follow-up each patient needs. Recent data suggest that mismatch repair mutations confer a greater risk for urothelial cancer. Additional large patient series as well as advancement of molecular testing may provide triage for Lynch syndrome patients in regards to the frequency and type of screening best suited for individual patient.