Hepatocyte nuclear factor-1β expression in clear cell adenocarcinomas of the bladder and urethra: diagnostic utility and implications for histogenesis

Clear Cell Adenocarcinoma of the Urinary Tract Primary to the Renal Pelvis: A Multi-institutional Clinicopathologic and Molecular Study of Five Patients

Clear cell adenocarcinoma (CCA) of the urinary tract is a rare malignancy and tumors involving the renal pelvis are notably sparse in the literature, with only 5 other patients reported. We present 5 patients, 4 women, and 1 man, with CCA of the renal pelvis. The age at presentation ranged from 29 to 81 years. The tumor size ranged from 4.5 to 8.0 cm. Tumors exhibited shared morphologic and immunohistochemical features with CCA of the female genital tract and those originating in the bladder and urethra, including cells with large nuclei, prominent nucleoli, nuclear hobnailing, and scant clear cytoplasm. Common immunohistochemical findings included reactivity for PAX8, CK7, HNF1β, and Napsin-A. One of the tumors arose in the background of a mixed epithelial and stromal tumor. Another tumor occurred in a renal allograft and tumor cells were positive for the BK virus, demonstrated by SV40 immunohistochemistry. All tumors were negative for TFE3 and TFEB rearrangement and lacked TERT alterations. Follow-up was limited with no recurrence in 4 patients at a maximum of 20 months follow-up and 1 patient died of an unrelated cause at 25 months of follow-up. Next-generation sequencing analysis of all 5 CCAs revealed mutations within genes implicated in DNA damage repair and chromatin remodeling pathways, including ATM , BRCA1 , BRCA2, ARID1A, DICER1, SMAD4, NOTCH1 , and MYC amplification. These molecular findings underscore the dysregulation of fundamental cellular processes essential for genomic integrity maintenance.

Diagnostic Approach to and Differential Diagnosis of Clear Cell and Glandular Lesions of the Lower Urinary Tract

CONTEXT.—

A variety of glandular and clear cell lesions may be seen in the urinary bladder and/or urethra, ranging from benign to malignant primary and secondary tumors. Lesions with no malignant potential include reactive processes, such as nephrogenic metaplasia, and may show similar morphologic features as an infiltrative neoplasm, particularly in small biopsies. Similarly, ectopic tissues of Müllerian origin may be seen in the lower urinary tract, and their distinction from a true glandular neoplasm is essential to avoid overtreatment. A wide variety of primary and secondary malignant tumors exist with varying degrees of glandular and clear cell features. Therefore, surgical pathologists must be aware of the full scope of possible lesions to avoid misdiagnosis.

OBJECTIVE.—

To provide a practical framework for approaching the diagnosis of clear cell and glandular lesions of the urinary bladder/urethra and prostate, highlighting the strengths and limitations of various diagnostic features and ancillary tests.

DATA SOURCES.—

A review of the current literature was performed to obtain data regarding up-to-date diagnostic features and ancillary studies.

CONCLUSIONS.—

In summary, distinct morphologic and immunohistochemical features and clinical and radiologic correlation are essential to establish an accurate diagnosis when such cases with glandular and clear features are encountered in the lower urinary tract.

The Application and Pitfalls of Immunohistochemical Markers in Challenging Diagnosis of Genitourinary Pathology

CONTEXT.—

The morphologic features of different entities in genitourinary pathology overlap, presenting a diagnostic challenge, especially when diagnostic materials are limited. Immunohistochemical markers are valuable when morphologic features alone are insufficient for definitive diagnosis. The World Health Organization classification of urinary and male genital tumors has been updated for 2022. An updated review of immunohistochemical markers for newly classified genitourinary neoplasms and their differential diagnosis is needed.

OBJECTIVE.—

To review immunohistochemical markers used in the diagnosis of genitourinary lesions in the kidney, bladder, prostate, and testis. We particularly emphasized difficult differential diagnosis and pitfalls in immunohistochemistry application and interpretation. New markers and new entities in the 2022 World Health Organization classifications of genitourinary tumors are reviewed. Recommended staining panels for commonly encountered difficult differential diagnoses and potential pitfalls are discussed.

DATA SOURCES.—

Review of current literature and our own experience.

CONCLUSIONS.—

Immunohistochemistry is a valuable tool in the diagnosis of problematic lesions of the genitourinary tract. However, the immunostains must be carefully interpreted in the context of morphologic findings with a thorough knowledge of pitfalls and limitations.

Primary Clear Cell Carcinoma of the Pancreas: A Systematic Review

Over the years, the world has witnessed many advances in diagnosing and treating multiple types of cancers. These breakthroughs have revolutionized the understanding of the molecular drive behind these neoplasms, leading to tangible therapeutic evolution and promising prognostic implications. However, pancreatic cancer remains a highly lethal disease. With recent discoveries, modern medicine has been able to delineate histopathologic subtypes of pancreatic cancer in hopes of improved diagnosis and treatment to improve survival. A once vague entity, clear cell adenocarcinoma of the pancreas, in particular, has been better characterized on a histopathological and molecular level over the past two decades. With novel technological support, this disease has become less inconspicuous, and more researchers have reported its occurrence. Its diagnosis relies heavily on a mix of histological and immunohistochemical clues such as a clear cell cytoplasm and positivity for cytokeratins and other markers. However, new molecular markers, such as hepatocyte nuclear factor 1 beta, have been associated with this entity and may aid in further diagnostic and therapeutic strategies. This review article aims to portray how the identification and description of clear cell adenocarcinoma of the pancreas have evolved over the past few decades and how this may impact future treatment strategies.

Hepatocyte nuclear factor 1 beta: A perspective in cancer

Hepatocyte nuclear factor 1 beta (HNF1 β/B) exists as a homeobox transcription factor having a vital role in the embryonic development of organs mainly liver, kidney and pancreas. Initially described as a gene causing maturity‐onset diabetes of the young (MODY), HNF1β expression deregulation and single nucleotide polymorphisms in HNF1β have now been associated with several tumours including endometrial, prostate, ovarian, hepatocellular, renal and colorectal cancers. Its function has been studied either as homodimer or heterodimer with HNF1α. In this review, the role of HNF1B in different cancers will be discussed along with the role of its splice variants, and its emerging role as a potential biomarker in cancer.

Facing treatment of non-urothelial bladder cancers in the immunotherapy era

Non-urothelial Bladder Cancer (BC) and variants of urothelial carcinoma account for up to 25 % of all BCs. Given their heterogeneity, these entities are not well represented in clinical trials and treatment remains challenging. Checkpoint inhibitor therapy has shown a role in the treatment of urothelial BC. By contrast, robust evidence regarding its use in other histological types is lacking. We aimed to provide a comprehensive update of non-urothelial and variant urothelial BC, exploring the evidence for immune checkpoint inhibitor therapy. A detailed analysis of the literature was conducted regarding epidemiology, aetiology, diagnosis, prognosis, treatment and outcomes of these patients in the immunotherapy era. A growing body of evidence suggests that immune checkpoint inhibition might have a role to play in non-urothelial BC, similarly to what happened with urothelial carcinomas.

The applicability and utility of immunohistochemical biomarkers in bladder pathology

Urinary bladder specimens are frequently encountered in the daily practice of surgical pathologists. The spectrum of pathologic entities encountered in bladder specimens is extraordinarily broad, and in some instances, immunohistochemical stains are used to help characterize challenging bladder lesions. Cost-effective biomarker selection tailored to the differential diagnosis facilitates an accurate diagnosis. This comprehensive review is prepared as a reference guide for the use of immunohistochemistry to categorize primary and secondary bladder neoplasms and to evaluate metastatic cancers for possible bladder origin.

Dataset for the reporting of carcinoma of the bladder-cystectomy, cystoprostatectomy and diverticulectomy specimens: recommendations from the International Collaboration on Cancer Reporting (ICCR)

The International Collaboration on Cancer Reporting (ICCR) is a not for profit organisation whose goal is to produce standardised internationally agreed and evidence-based datasets for pathology reporting. With input from pathologists worldwide, the datasets are intended to be uniform and structured. They include all items necessary for an objective and accurate pathology report which enables clinicians to apply the best treatment for the patient. This dataset has had input from a multidisciplinary ICCR expert panel. The rationale for some items being required and others recommended is explained, based on the latest literature. The dataset incorporates data from the World Health Organization (WHO) 2016, and also from the latest (8th edition) TNM staging system of the American Joint Committee on Cancer (AJCC). Fifteen required elements and eight recommended items are described. This dataset provides all the details for a precise and valuable pathology report required for patient management and prognostication. This dataset is intended for worldwide use, and should facilitate the collection of standardised comparable data on bladder carcinoma at an international level.

Clear cell urothelial carcinoma of the urinary bladder - a rare pathological entity. A case report and a systematic review of the literature

The most common histological type of urinary bladder cancer is urothelial carcinoma (UC). In contrast, the clear cell variant of urothelial carcinoma (CCUC) is quite a rare neoplasm. In this study, we report a case of an 81-year-old male, presenting with gross hematuria and acute urinary retention, which was subsequently diagnosed with CCUC at our pathology department. Furthermore, we provide a short systematic review of the literature (PubMed, Scopus, and Science Citation Index) for this rare histopathological entity and a brief discussion about its morphological and immunohistochemical (IHC) characteristics.

Non-urothelial carcinomas of the bladder

Non-urothelial carcinomas involving the bladder are uncommon and often diagnostically challenging. These carcinomas may show squamous, adenocarcinomatous or neuroendocrine features, with immunohistochemical stains aiding the diagnosis in only a subset of cases. The clinical history in non-urothelial bladder carcinomas is important, given that the differential diagnosis often includes secondary involvement of the bladder by direct extension or metastasis from carcinomas at other sites. This paper will review non-urothelial carcinomas in each of these three morphological categories, emphasising recent changes in diagnostic grouping and challenges in the histopathological diagnosis. Review of bladder cancers with squamous morphology will include discussion of conventional squamous cell carcinoma and verrucous carcinoma and their distinction from urothelial carcinoma with extensive squamous differentiation. Bladder carcinomas with adenocarcinomatous change will include primary bladder adenocarcinoma, urachal adenocarcinoma and tumours of Müllerian type. Finally, neuroendocrine neoplasms of the bladder, including well-differentiated neuroendocrine tumour and neuroendocrine carcinomas, will be discussed. Associated surface findings, risk factors and prognostic features will be described.

A review on hepatocyte nuclear factor-1beta and tumor

Hepatocyte nuclear factor-1beta (HNF1β) was initially identified as a liver-specific transcription factor. It is a homeobox transcription factor that functions as a homodimer or heterodimer with HNF1α. HNF1β plays an important role in organogenesis during embryonic stage, especially of the liver, kidney, and pancreas. Mutations in the HNF1β gene cause maturity-onset diabetes of the young type 5 (MODY5), renal cysts, genital malformations, and pancreas atrophy. Recently, it has been shown that the expression of HNF1β is associated with cancer risk in several tumors, including hepatocellular carcinoma, pancreatic carcinoma, renal cancer, ovarian cancer, endometrial cancer, and prostate cancer. HNF1β also regulates the expression of genes associated with stem/progenitor cells, which indicates that HNF1β may play an important role in stem cell regulation. In this review, we discuss some of the current developments about HNF1β and tumor, the relationship between HNF1β and stem/progenitor cells, and the potential pathogenesis of HNF1β in various tumors.

Overexpression Of Hepatocyte Nuclear Factor-1beta Predicting Poor Prognosis Is Associated With Biliary Phenotype In Patients With Hepatocellular Carcinoma

Hepatocyte nuclear factor-1beta (HNF-1B) is involved in the hepatobiliary specification of hepatoblasts to cholangiocytes during liver development, and is strongly expressed throughout adult biliary epithelium. The aim of this study was to examine the expression of HNF-1B in different pathologic subtypes of primary liver cancer, including hepatocellular carcinoma (HCC) and cholangiocarcinoma (ICC), and the relationship between HNF-1B expression, clinicopathological features and prognosis. We retrospectively investigated 2 cohorts of patients, including 183 HCCs and 69 ICCs. The expression of HNF-1B was examined by immunohistochemistry. We found that HNF-1B expression was associated with pathological subtype of primary tumor, and HNF-1B expression in HCC tissue may be associated with the change of phenotype on recurrence. The HNF-1B expression was positively correlated with biliary/HPC (hepatic progenitor cell) markers expression. Further, multivariable analysis showed that HNF-1B expression was an independent prognostic factor for both overall survival and disease-free survival of HCC patients. However, no correlation between HNF-1B expression and survival was found in ICC patients. In summary, HCC with high HNF-1B expression displayed biliary phenotype and tended to show poorer prognosis. HNF-1B-positive malignant cells could be bipotential cells and give rise to both hepatocytic and cholangiocytic lineages during tumorigenesis.

Immunohistochemistry in undifferentiated neoplasm/tumor of uncertain origin

CONTEXT

Immunohistochemistry has become an indispensable ancillary study in the identification and classification of undifferentiated neoplasms/tumors of uncertain origin. The diagnostic accuracy has significantly improved because of the continuous discoveries of tissue-specific biomarkers and the development of effective immunohistochemical panels.

OBJECTIVES

To identify and classify undifferentiated neoplasms/tumors of uncertain origin by immunohistochemistry.

DATA SOURCES

Literature review and authors' research data and personal practice experience were used.

CONCLUSIONS

To better guide therapeutic decisions and predict prognostic outcomes, it is crucial to differentiate the specific lineage of an undifferentiated neoplasm. Application of appropriate immunohistochemical panels enables the accurate classification of most undifferentiated neoplasms. Knowing the utilities and pitfalls of each tissue-specific biomarker is essential for avoiding potential diagnostic errors because an absolutely tissue-specific biomarker is exceptionally rare. We review frequently used tissue-specific biomarkers, provide effective panels, and recommend diagnostic algorithms as a standard approach to undifferentiated neoplasms.

Clear cell urothelial carcinoma of the urinary bladder: a case report and review of the literature

Introduction

The occurrence of clear cell tumors in the bladder is not uncommon. Clear cell dysplasia is well-described and characterized by focal replacement of transitional mucosa by cells with abundant clear cytoplasm, nuclear enlargement, and a granular chromatin pattern. Clear cells can also be seen in clear cell adenocarcinoma, which is rare, comprising 0.5% to 2.0% of the reported bladder carcinomas. Other clear cell tumors found in the bladder to be considered in the differential diagnosis are tumors of Müllerian origin and metastatic lesions, such as renal cell carcinoma, clear cell sarcoma, and malignant melanoma. Clear cell urothelial carcinoma is exceedingly rare, with only nine clinical cases described in the literature.

Case presentation

We report the case of a 75-year-old Caucasian man who presented with intermittent hematuria, in whom a bladder tumor was identified. A final histopathology examination of a cystoprostatectomy specimen revealed a pT3b, G3 urothelial carcinoma of clear cell type (>90% clear cells) and a prostatic adenocarcinoma of Gleason grade 3+3 (score=6). The bladder tumor consisted of sheets of malignant cells with severe nuclear atypia and abundant clear cytoplasm; no glandular or tubular structures were identified. Tumor cells were periodic acid-Schiff positive and negative after diastase treatment; additional mucicarmine and oil red O stains were negative. Immunohistochemical stains showed the tumor cells positive for cytokeratin 7 (CK7), p63 (>80% nuclei), p53 (about 30% nuclei), vimentin, E-cadherin, cluster of differentiation (CD10), and Ki-67 (>70% nuclei). Stains for cell adhesion molecule 5.2 (CAM 5.2), CD117, cytokeratin 20 (CK20), human melanoma black 45 (HMB-45), paired box protein (PAX 8), placental alkaline phosphatase (PLAP), prostate specific antigen (PSA), renal cell carcinoma (RCC), cancer antigen 25 (CA25), leukocyte common antigen (LC), S-100 protein, and uroplakin III were all negative.

Conclusions

The tumor marker profile was consistent with clear cell type carcinoma of urothelial origin. Within the differential diagnoses, we ruled out other possible tumor types such as urothelial carcinoma with focal clear cell differentiation, clear cell adenocarcinoma, Müllerian tumors, and metastatic disease.

Primary urethral clear-cell adenocarcinoma: comprehensive analysis by surgical pathology, cytopathology, and next-generation sequencing

Primary clear-cell adenocarcinoma of the urethra, a rare tumor that histomorphologically resembles clear-cell carcinoma of the female genital tract, occurs predominantly in women and is associated with a relatively poor prognosis. The histogenesis of this rare urethral neoplasm has not been completely resolved, but it is thought to arise from either müllerian rests or metaplastic urothelium. Herein, we present comprehensive surgical pathological and cytopathological findings from a patient with primary urethral clear-cell adenocarcinoma and describe next-generation sequencing results for this patient's unique tumor-the first such reported characterization of molecular aberrations in urethral clear-cell adenocarcinoma at the transcriptomic and genomic levels. Transcriptome analysis revealed novel gene fusion candidates, including ANKRD28-FNDC3B. Whole-exome analysis demonstrated focal copy number loss at the SMAD4 and ARID2 loci and 38 somatic mutations, including a truncating mutation in ATM and a novel nonsynonymous mutation in ALK.

Clear cell adenocarcinoma of the renal pelvis in a male patient

Carcinoma of the renal pelvis is an uncommon renal neoplasm. Clear cell adenocarcinoma in the urinary tract is rare and has a histomorphology resembling that of the female genital tract. We herein present a case of clear cell adenocarcinoma of the renal pelvis, which is the first example in a male patient to our knowledge. A 54-year-old man presented with right flank pain. The tumor was associated with renal stones and hydronephrosis and invaded into the peripelvic fat tissue with regional lymph node metastasis. The patient died of metastatic disease six months postoperatively. Histologically, the tumor showed complex papillary architecture lined with clear and hobnail cells. Clear cell adenocarcinoma of the renal pelvis may pose a diagnostic challenge on histological grounds, particularly in the distinction from renal cell carcinoma. The immunohistochemical stains could help confirm the diagnosis. Due to its rarity, an effective treatment regimen remains to be determined.

Hepatocyte nuclear factor-1β is not a specific marker of clear cell carcinoma in serous effusions

BACKGROUND

The transcription factor hepatocyte nuclear factor-1β (HNF1β) has been reported to be a specific clear cell carcinoma marker, but its role in the diagnosis of serous effusions is largely unexplored. The objective of this study was to assess the diagnostic role of 2 commercial antibodies against HNF1β in effusion specimens.

METHODS

Effusions (n = 101), consisting of 43 ovarian adenocarcinomas (26 serous, 14 clear cell, 3 endometrioid), 37 nonovarian adenocarcinomas, 10 malignant mesotheliomas, 2 nonepithelial cancers, and 9 reactive specimens, were immunostained using antibodies from Santa Cruz Biotechnology Inc (Santa Cruz, Calif) and Atlas Antibodies AB (Stockholm, Sweden).

RESULTS

Use of the Santa Cruz antibody was associated with cytoplasmic or background staining in some specimens, whereas distinct staining with minimal background was observed using the Atlas antibody. The Santa Cruz antibody performed better in differentiating clear cell carcinoma from serous ovarian carcinoma and breast carcinoma, whereas staining was consistently negative in benign and malignant mesotheliomas using both antibodies. Distinct nuclear expression of HNF1β was observed in lung and gastrointestinal carcinomas, most often using the Atlas antibody.

CONCLUSIONS

The HNF1β antibody from Atlas performed better than its counterpart from Santa Cruz in terms of staining quality, but was less specific for clear cell carcinoma. Although HNF1β may be of diagnostic value in differentiating clear cell from serous carcinoma in cases with proven genital origin, the role of this marker is questionable in the differential diagnosis between the former tumors and adenocarcinomas of other origin, particularly in the setting of metastasis from an unknown primary tumor.

Histology and immunohistochemistry of clear cell adenocarcinoma of the urethra: histogenesis and diagnostic problems

Clear cell adenocarcinoma (CCAC) of the urethra is a rare neoplasm, morphologically identical to its homologue arising in the female genital tract. The histogenesis of this neoplasm is uncertain. We present clinical, histopathologic, and immunohistochemical findings of four CCAC of the urethra and discuss the histogenesis and difficulties in diagnosis and differential diagnosis. CCAC of the urethra occurred in females (4/4). Two neoplasms were identified in urethral diverticulum; one of the two cases, in close proximity to a nephrogenic adenoma. CCAC exhibited tubulocystic, papillary, and diffuse/solid growth patterns. The neoplastic cells were cuboidal or columnar with eosinophilic or clear cytoplasm, and nuclear pleomorphism of at least moderate degree. Hobnail features and tumor necrosis were also observed. CCAC expressed p53 (4/4), AMACR (3/4), vimentin (3/4), PAX8 (2/4), CK7 (2/4), cytokeratin 34betaE12 (2/4), RCC (1/4), and CK20 (1/4) and were negative for PSA, WT1, ER, CA 125, uroplakin III, p16, and p63. The immunohistochemical profile supports a possible renal tubular cell differentiation/mesonephric origin for some urethral CCAC. Nephrogenic adenoma and metastatic clear cell carcinoma are the most important differential diagnostic considerations. Multicenter studies on more cases may improve our understanding of this malignancy.

Optimizing molecular-targeted therapies in ovarian cancer: the renewed surge of interest in ovarian cancer biomarkers and cell signaling pathways

The hallmarks of ovarian cancer encompass the development of resistance, disease recurrence and poor prognosis. Ovarian cancer cells express gene signatures which pose significant challenges for cancer drug development, therapeutics, prevention and management. Despite enhancements in contemporary tumor debulking surgery, tentative combination regimens and abdominal radiation which can achieve beneficial response rates, the majority of ovarian cancer patients not only experience adverse effects, but also eventually relapse. Therefore, additional therapeutic possibilities need to be explored to minimize adverse events and prolong progression-free and overall response rates in ovarian cancer patients. Currently, a revival in cancer drug discovery is devoted to identifying diagnostic and prognostic ovarian cancer biomarkers. However, the sensitivity and reliability of such biomarkers may be complicated by mutations in the BRCA1 or BRCA2 genes, diverse genetic risk factors, unidentified initiation and progression elements, molecular tumor heterogeneity and disease staging. There is thus a dire need to expand existing ovarian cancer therapies with broad-spectrum and individualized molecular targeted approaches. The aim of this review is to profile recent developments in our understanding of the interrelationships among selected ovarian tumor biomarkers, heterogeneous expression signatures and related molecular signal transduction pathways, and their translation into more efficacious targeted treatment rationales.