p16 expression is not associated with human papillomavirus in urinary bladder squamous cell carcinoma

Adenocarcinomas of the Gynecologic Tract Involving the Urinary Bladder: A Series of 16 Cases Potentially Mimicking Urothelial Malignancy

CONTEXT.—

There is limited literature describing gynecologic adenocarcinomas involving the urinary bladder and potential diagnostic pitfalls.

OBJECTIVE.—

To describe key features distinguishing metastatic (or extension of) gynecologic adenocarcinomas from urothelial carcinomas with glandular differentiation.

DESIGN.—

Retrospective review of surgical pathology cases of gynecologic adenocarcinomas involving the bladder from 2 different institutions, retrieved from surgical pathology archives, was performed. Morphologic features were recorded, along with immunohistochemistry results when available. Electronic medical records were reviewed for clinical and radiographic information.

RESULTS.—

Sixteen cases of gynecologic adenocarcinomas (9 endometrial endometrioid adenocarcinomas, 4 endometrial serous carcinomas, 2 high-grade tubo-ovarian serous carcinomas, and 1 cervical adenosquamous carcinoma) involving the bladder were identified. All included cases had mucosal involvement potentially mimicking primary bladder neoplasms, including 4 cases originally diagnosed as urinary carcinomas. Tumors expressed keratin 7 (12 of 13; 92%), PAX8 (11 of 12; 92%), estrogen receptor (11 of 15; 73%), p16 (8 of 11; 73%), progesterone receptor (8 of 14; 57%), GATA3 (5 of 12; 42%), and p63 (3 of 11; 27%); all tumors were negative for keratin 20 (0 of 12). Features supportive of Müllerian origin included prior history of gynecologic malignancy, lack of morphologic heterogeneity in nonendometrioid tumors, and immunophenotypic coexpression of PAX8 and estrogen receptor with absent GATA3. Potential pitfalls seen in a subset of cases included misleading radiologic and cystoscopic findings, replacement of the overlying urothelial mucosa by tumor mimicking precursor lesions, focal GATA3 and/or p63 positivity, and areas of squamous differentiation in tumors of endometrioid histology.

CONCLUSIONS.—

A combination of clinical history, certain morphologic features, and proper selection of immunohistochemical stains is key for the correct diagnosis of secondary gynecologic adenocarcinomas involving the urinary bladder.

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.

Association of human papillomavirus (HPV), p16, p53 and p63 expression with non-bilharzia-associated squamous cell carcinoma of the bladder and algorithm construction for histopathological grading prediction

OBJECTIVE

To investigate the expression of human papillomavirus (HPV), p16, p53, and p63 in non-schistosomiasis-related squamous cell carcinoma of the bladder and to develop an accurate and automated tool to predict histological classification based on clinicopathological features.

METHODS

Twenty-eight patients with primary bladder pure squamous cell carcinoma who underwent cystectomy or transurethral resection of bladder tumor (TURBT) for bladder cancer between January 2011 and July 2017 were evaluated. Clinical data and follow-up information were obtained from medical records. Formalin-fixed, paraffin-embedded surgical specimens were used for immunohistochemical staining for p16, p53, and p63. Human papillomavirus detection was evaluated by PCR. Statistical analysis was performed, and statistical significance was set at p<0.05. Finally, decision trees were built to classify patients' prognostic features. Leave-one-out cross-validation was used to test the generalizability of the model.

RESULTS

Neither direct HPV detection nor its indirect marker (p16 protein) was identified in most cases. The absence of p16 was correlated with less aggressive histological grading (p=0.040). The positive p16 staining detection found only in pT1 and pT2 cases in our sample suggests a possible role for this tumor suppressor protein in the initial stages of bladder squamous cell carcinoma. The decision trees constructed described the relationship between clinical features, such as hematuria/dysuria, the level of tumor invasion, HPV status, lymphovascular invasion, gender, age, compromised lymph nodes, and tumor degree differentiation, with high classification accuracy.

CONCLUSION

The algorithm classifier approach established decision pathways for semi-automatic tumor histological classification, laying the foundation for tailored semi-automated decision support systems for pathologists.

The association between human papillomavirus and bladder cancer: Evidence from meta-analysis and two-sample mendelian randomization

INTRODUCTION

Bladder cancer (BCa) is the 10th most common type of cancer worldwide, and human papillomavirus (HPV) is the most common sexually transmitted infection. However, the relationship between HPV infection and the risk of BCa is still controversial and inconclusive.

METHODS

This systematic review and meta-analysis were conducted following the PRISMA 2020 reporting guideline. This study searched four bibliographic databases with no language limitation. The databases included PubMed (Medline), EMBASE, Cochrane Library, and Web of Science. Studies evaluating the interaction between HPV infection and the risk of BCa from inception through May 21, 2022, were identified and used in this study. This study estimated the overall and type-specific HPV prevalence and 95% confidence intervals (95% CI) using Random Effects models and Fixed Effects models. In addition, this study also calculated the pooled odds ratio and pooled risk ratio with 95% CI to assess the effect of HPV infection on the risk and prognosis of bladder cancer. Two-sample mendelian randomization (MR) study using genetic variants associated with HPV E7 protein as instrumental variables were also conducted.

RESULTS

This study retrieved 80 articles from the four bibliographic databases. Of the total, 27 were case-control studies, and 53 were cross-sectional studies. The results showed that the prevalence of HPV was 16% (95% CI: 11%-21%) among the BCa patients, most of which were HPV-16 (5.99% [95% CI: 3.03%-9.69%]) and HPV-18 (3.68% [95% CI: 1.72%-6.16%]) subtypes. However, the study found that the prevalence varied by region, detection method, BCa histological type, and sample source. A significantly increased risk of BCa was shown for the positivity of overall HPV (odds ratio [OR], 3.35 [95% CI: 1.75-6.43]), which was also influenced by study region, detection method, histological type, and sample source. In addition, the study found that HPV infection was significantly associated with the progression of BCa (RR, 1.73 [95% CI: 1.39-2.15]). The two-sample MR analysis found that both HPV 16 and 18 E7 protein exposure increased the risk of BCa (HPV 16 E7 protein: IVW OR per unit increase in protein level = 1.0004 [95% CI: 1.0002-1.0006]; p = 0.0011; HPV 18 E7 protein: IVW OR per unit increase in protein level = 1.0003 [95% CI: 1.0001-1.0005]; p = 0.0089).

CONCLUSION

In conclusion, HPV may play a role in bladder carcinogenesis and contribute to a worse prognosis for patients with BCa. Therefore, it is necessary for people, especially men, to get vaccinated for HPV vaccination to prevent bladder cancer.

Prevalence of Human Papilloma Virus Infection in Bladder Cancer: A Systematic Review

The etiology of bladder cancer is known to be associated with behavioral and environmental factors. Moreover, several studies suggested a potential role of HPV infection in the pathogenesis with controversial results. A systematic review was conducted to assess the role of HPV. A total of 46 articles that reported the prevalence of HPV infection in squamous (SCC), urothelial (UC), and transitional cell carcinomas (TCC) were selected. A pooled prevalence of 19% was found, with a significant difference in SCC that was mainly driven by HPV-16. Moreover, infection prevalence in case-control studies showed a higher risk of bladder cancer in HPV-positive cases (OR: 7.84; p-value < 0.00001). The results may suggest an etiologic role of HPV in bladder cancer. HPV vaccine administration in both sexes could be key to prevent the infection caused by high-risk genotypes.

Bladder cancer and human papillomavirus association: a systematic review and meta-analysis

BACKGROUND

The possible association of human papillomavirus (HPV) and bladder cancer has been controversial. Older findings suggest a significant association between the virus and bladder cancer. The aim of this study was to evaluate the data from the last ten years to estimate the prevalence of the virus in bladder cancer patients and to assess the association between the virus and cancer.

METHOD

A search of major databases was conducted to retrieve published English language studies between January 2011 and March 2021. In the present study overall prevalence of the virus in bladder cancer patients was estimated along with the prevalence of subgroups. Also, the possible associations between the prevalence of the virus and bladder cancer and the possible impact of variables in the geographical area and the type of sample were measured by comprehensive meta-analysis software (V2.2, BIOSTAT).

RESULTS

Unlike previous studies, despite the relatively high prevalence of the virus [pooled prevalence: 14.3% (95% CI 8.9-22.2%)] no significant association was found between HPV and bladder cancer (OR 2.077, 95% CI 0.940-4.587). No significant association was found between geographical area (except Asia) and type of sample with bladder cancer.

CONCLUSIONS

Given the significant prevalence, despite the insignificance of the association between virus and cancer, it seems that more studies with case-control design are needed to elucidate this association.

Detection of HPV infection in urothelial carcinoma using RNAscope: Clinicopathological characterization

Background

Human papillomavirus (HPV) is a well‐established mucosotropic carcinogen, but its impact on urothelial neoplasm is unclear. We aimed to clarify the clinical and pathological features of HPV‐related urothelial carcinoma (UC).

Methods

Tissue samples of 228 cases of UC were obtained from the bladder, upper and lower urinary tract, and metastatic sites to construct a tissue microarray. The samples were analyzed for the presence of HPV by a highly sensitive and specific mRNA in situ hybridization (RISH) technique (RNAscope) with a probe that can detect 18 varieties of high‐risk HPV. We also conducted immunohistochemistry (IHC) for a major HPV capsid antibody and DNA‐PCR.

Results

The HPV detection rates varied among the methods; probably due to low HPV copy numbers in UC tissues and the insufficient specificity and sensitivity of the IHC and PCR assays. The RISH method had the highest accuracy and identified HPV infection in 12 (5.2%) of the cases. The histopathological analysis of the HPV‐positive UC showed six cases of usual type UC, five cases of UC with squamous differentiation (UC_SqD), and one case of micropapillary UC. The HPV detection rate was six‐fold higher in the cases of UC_SqD than in the other variants of UC (odds ratio [OR] =8.9, p = 0.002). In addition, HPV infection showed a significant association with tumor grade (OR =9.8, p = 0.03) and stage (OR =4.7, p = 0.03) of UC. Moreover, the metastatic rate was higher in HPV‐positive than in negative UC (OR =3.4).

Conclusion

These data indicate that although the incidence of HPV infection in UC is low, it is significantly associated with squamous differentiation and poor prognosis. Furthermore, our observations show that RNAscope is an ideal method for HPV detection in UC compared with the other standard approaches such as IHC and PCR assays.

Expression and prognostic value of SULT1A2 in bladder cancer

Sulfotransferase Family 1A Member 2 (SULT1A2) is a protein coding gene. Several studies have reported that SULT1A2 may have a chemical carcinogenic effect if expressed as a functional protein. The present study aimed to investigate the expression and potential role of SULT1A2 in bladder cancer (BC). Data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus databases were used to analyze SULT1A2 expression in BC. In addition, reverse transcription-quantitative PCR and western blot analyses were performed to detect SULT1A2 expression in BC cells and tissues. Immunohistochemistry analysis was performed on 100 formalin-fixed, paraffin-embedded BC tissues and corresponding adjacent normal bladder tissues (ANBTs) to verify SULT1A2 expression and determine the clinical significance of SULT1A2 in BC. Gene set enrichment analysis (GSEA) was performed to determine the potential biological processes and internal molecular mechanisms. The results demonstrated that SULT1A2 was highly expressed in BC tissues compared with ANBTs. Furthermore, high SULT1A2 expression was significantly associated with the staging of BC. Analyses of TCGA datasets and BC tissue microarray indicated that high SULT1A2 expression was significantly associated with a favorable overall survival in patients with BC. In addition, GSEA revealed pathways, diseases and biological processes associated with SULT1A2. Taken together, the results of the present study suggest that SULT1A2 acts as an oncogene in BC, and thus may serve as a biomarker for tumor staging and prognosis in patients with BC.

Secondary tumors of the bladder: A survival outcome study

The urinary bladder may be involved by a variety of secondary tumors that originate from other organs. Bladder secondary tumors are rare and may be mistaken as bladder primary tumors because of their overlapping morphologic features. To avoid the diagnostic pitfalls, we analyzed the clinicopathologic features of bladder secondary tumors in a large cohort of patients. Our patient cohort consisted of 45 females and 38 males with a mean age of 58.7 ± 15.4 years (range 10-87 years). The tumors involved the bladder via direct extension from adjacent organs (n = 42) and distant metastasis (n = 41). In females, the majority of secondary tumors originated from the gynecologic tract (n = 25), and other common origins included the colon/rectum (n = 5) and breast (n = 4). In males, the most common origin was the prostate (n = 18), followed by the colon/rectum (n = 4) and kidney (n = 3). 75.9% of the secondary tumors were adenocarcinoma (n = 63), and other common tumor types included sarcoma (n = 6), squamous cell carcinoma (n = 5), melanoma (n = 4), and neuroendocrine carcinoma (n = 3). 67.5% of patients (n = 56) died of the disease with a median overall survival of 23 months from the time of secondary involvement of the bladder. Patients with secondary tumors via direct extension had a median survival time of 20 months, which was not significantly different from that for patients with secondary involvement via distant metastasis (24 months) (p = 0.83). Median survival in cases with prostate primary was 20 months as compared to 23 months for all other tumor types (p = 0.68). The majority of secondary tumors are composed of adenocarcinoma, which highlights the importance of differentiating primary from secondary involvement in bladder adenocarcinoma. Regardless of the origin, bladder secondary tumors are associated with a poor prognosis.

Squamous Cell Carcinoma of the Bladder Is Not Associated With High-risk HPV

OBJECTIVE

To evaluate the clinical features, pathologic features, and prevalence of human papilloma virus (HPV) in squamous cell carcinoma (SCC) of the bladder. SCC of the bladder is known to be associated with conditions that cause chronic inflammation/irritation. The literature is inconsistent regarding the association of HPV with pure SCC of the bladder.

METHODS

A multi-institutional study identified cases of SCC of the bladder. Pure squamous histology and the absence of urothelial carcinoma in situ were required for inclusion. Clinical and pathologic features were collected, and tissues were evaluated for high-risk HPV using p16 immunohistochemistry and in situ hybridization.

RESULTS

We identified 207 cases of SCC of the bladder. Risk factors for bladder cancer included smoking (133/207, 64%) and chronic bladder irritation (83/207, 40%). The majority (155/207, 75%) of patients had > pT2 disease. Mean tumor size was 5.6 ± 3.0 cm and 36/207 (17%) patients had lymph node positive disease. p16 immunohistochemistry was positive in 52/204 (25%) cases but high-risk HPV was identified with in situ hybridization in only 1 (0.5%) case. Tumor size, stage, number of lymph nodes removed, number of positive lymph nodes, lymphovascular invasion, perineural invasion, and positive margins each were associated with cancer-specific mortality when adjusted for demographic factors. A multivariate analysis of variable importance further revealed sex and race as important factors in predicting cancer-specific mortality.

CONCLUSION

SCC of the bladder is an aggressive histologic subtype. Although bladder SCC can express p16, it is not typically associated with high-risk HPV, although rare cases can occur.

Prevalence of high-risk human papillomavirus in primary squamous cell carcinoma of urinary bladder

Studies have demonstrated an etiologic role of high-risk human papillomavirus (HR-HPV) infection for epithelial malignancies, including most cervical carcinomas, anogenital cancers, and carcinomas of the head and neck; however, a causative role of HPV infection for bladder cancer is controversial. The purpose of this study was to investigate the prevalence of HR-HPV in primary bladder carcinoma to determine the association between HPV infection and the squamous cell component of urothelial carcinoma of the bladder. Furthermore, we evaluated the utility of p16 overexpression as a surrogate marker for HPV infection in these cancers and the correlation of this with tumor stage. Our study included 33 cases of squamous cell carcinoma (SCC) of the urinary bladder. Tumors deemed primary from the bladder were selected and either showed predominant (>50 %) or pure squamous differentiation. Immunohistochemical study for p16 and HR-HPV by RNA in situ hybridization (ISH) was performed in all cases. p16 expression was detected in 7 cases (28 %, 7/25) of urothelial carcinoma with squamous differentiation and not detected in any of the 8 cases (0%, 0/8) of pure SCC. Detection of HR-HPV by ISH was negative in all 33 cases (0%, 0/33). There was no association between p16 overexpression and the presence of HPV infection in squamous cell carcinomas of the bladder. p16 should not be used as a surrogate marker for evidence of HPV infection. Our study suggests that HPV infection does not play an etiologic role in the development of bladder cancer and should not be used as a diagnostic adjunct for these cases.

Human papillomavirus and urinary bladder cancer revisited

This review aims to present data on the association between human papillomavirus (HPV) and urinary bladder cancer (BC), especially of the subtype squamous cell carcinoma (SCC). Furthermore, the current data on the relation between p16, HPV, and BC are reviewed. PubMed was searched for 'Humans' [MESH] AND 'Papillomaviridae' [MESH] AND 'Urinary Bladder Neoplasms' [MESH], resulting in 157 potential articles. After profound reviewing, 18 articles were included in this review. Only original articles in English were included. A variable number of HPV genotypes in a small number of cases have been investigated in several studies with various methodology. HPV was present in 0-100% of cases depending on inclusion and exclusion criteria. SCC studies are mostly hampered by low number of cases whereas the few studies with a high number show a slightly higher prevalence of different HPV genotypes compared to pure urothelial carcinoma. Studies on p16 status in HPV positive cases are even more scarcely reported and show conflicting results. Most studies fail to prove clear-cut relevance of HPV in BC irrespectively of histological subtype. Negative p16 staining cannot rule out positive HPV status.

GATA3 Expression in Common Gynecologic Carcinomas: A Potential Pitfall

GATA binding protein 3 (GATA3) immunohistochemistry is primarily used as a marker of breast and urothelial differentiation, particularly in metastatic settings. In the gynecologic tract it also serves a robust marker for mesonephric and trophoblastic tumors. However, expression has also been described in more common malignancies of gynecologic tract including ovarian, endometrial, and cervical carcinomas. Data on the distribution of GATA3 expression in gynecologic malignancies is somewhat limited, particularly across different histologic subtypes of ovarian, endometrial, and cervical carcinomas. To assess the rates of GATA3 expression among common gynecologic cancers of various histologic types, 100 ovarian carcinomas, 64 endometrial carcinomas/atypical hyperplasias, 16 cervical squamous cell carcinomas (SCCs), and 14 endocervical adenocarcinomas were evaluated by immunohistochemistry for GATA3 positivity. Eight percent of endometrial carcinomas expressed GATA3, including 2 serous carcinomas, 1 carcinosarcoma, and 1 case of atypical hyperplasia. Six percent of ovarian carcinomas were GATA3-positive including 2 clear cell carcinomas, 2 mucinous adenocarcinomas, and 2 high-grade serous carcinomas. Thirty-eight percent of cervical SCCs showed weak to moderate staining in up to 50% of tumor cells. All endocervical adenocarcinomas were entirely negative for GATA3. In summary, GATA3 shows focal weak to moderate expression in a subset of endometrial and ovarian carcinomas. In contrast, usual-type endocervical adenocarcinomas are typically negative for GATA3, which can be helpful in differentiating them from mesonephric proliferations or carcinomas. A larger proportion of cervical SCCs express GATA3, therefore caution should be exercised when using this stain in the setting of a lower genitourinary carcinomas.

Updates on the Genomics of Bladder Cancer and Novel Molecular Taxonomy

Urothelial carcinoma (UC) is the most common malignant neoplasm of the bladder that encompasses a wide spectrum of histopathologic features and various molecular alterations and subtypes, responsible for its significant morphologic and genomic heterogeneity. Morphologically, in addition to classic UC (not otherwise specified), many well documented variant histologies are a common finding in invasive UC, and include squamous, glandular, micropapillary, sarcomatoid, small cell/neuroendocrine, clear cell, lymphoepithelioma-like, and plasmacytoid types, among others. This review provides an update on the recent advances in the molecular characterization and novel molecular taxonomy of UC and variant histologies.

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.

Detection of High-Risk Human Papillomavirus in Oral Cavity Squamous Cell Carcinoma Using Multiple Analytes and Their Role in Patient Survival

PURPOSE

Accurate detection of human papillomavirus (HPV) in oral cavity squamous cell carcinoma (OSCC) is essential to understanding the role of HPV in disease prognosis and management of patients. We used different analytes and methods to understand the true prevalence of HPV in a cohort of patients with OSCC with different molecular backgrounds, and we correlated HPV data with patient survival.

METHODS

We integrated data from multiple analytes (HPV DNA, HPV RNA, and p16), assays (immunohistochemistry, polymerase chain reaction [PCR], quantitative PCR [qPCR], and digital PCR), and molecular changes (somatic mutations and DNA methylation) from 153 patients with OSCC to correlate p16 expression, HPV DNA, and HPV RNA with HPV incidence and patient survival.

RESULTS

High prevalence (33% to 58%) of HPV16/18 DNA did not correlate with the presence of transcriptionally active viral genomes (15%) in tumors. Eighteen percent of the tumors were p16 positive and only 6% were both HPV DNA and HPV RNA positive. Most tumors with relatively high copy number HPV DNA and/or HPV RNA, but not with HPV DNA alone (irrespective of copy number), were wild-type for TP53 and CASP8 genes. In our study, p16 protein, HPV DNA, and HPV RNA, either alone or in combination, did not correlate with patient survival. Nine HPV-associated genes stratified the virus-positive from the virus-negative tumor group with high confidence ( P < .008) when HPV DNA copy number and/or HPV RNA were considered to define HPV positivity, and not HPV DNA alone, irrespective of copy number ( P < .2).

CONCLUSION

In OSCC, the presence of both HPV RNA and p16 is rare. HPV DNA alone is not an accurate measure of HPV positivity and therefore may not be informative. HPV DNA, HPV RNA, and p16 do not correlate with patients' outcome.

Molecular Pathologic Subtyping of Urothelial Bladder Carcinoma in Young Patients

Urothelial cancer is a heterogeneous disease with different molecular pathways that produce distinct molecular subtypes with specific characteristics and patient survival outcomes that require different therapeutic methods. Urothelial tumors in young patients appear to have distinct genetic features compared with their counterparts in older patients. Using a Lund subtype-specific immunohistochemistry panel, we performed molecular subtype profiling of an urothelial carcinoma case series (n = 49) in patients younger than 45 years of age. We demonstrate that the urothelial carcinoma in young patients tends to be of molecular urothelial-like A subtype (80%) and is associated with favorable, recurrent-free survival (P = .022). In the urothelial-like cluster, we identified a portion of patients (10%) with high-grade non-muscle-invasive cancers (so-called urothelial-like D type) that showed significantly higher levels of squamous differentiation and p16, E2F3, and ki67 expression in addition to aberrant expression of Ck20 and a trend toward lower recurrent-free survival (P = .057). Segregation of the cohort according to the decade of occurrence revealed that all tumors (n = 8) of patients younger than 30 years were clearly classified as urothelial-like A subtype. Statistically more aggressive molecular subtypes, such as urothelial-like D and basal/squamous-like (6%) subtypes, were identified in patients older than 30 years of age. Genomically unstable (2%) and mesenchymal-like (2%) subtypes were classified in the 40- to 44-year age group only. These data suggest that more aggressive molecular subtypes of bladder carcinoma appear and become more frequent with age. Further investigations are needed to validate this hypothesis.

Immunohistochemical Pitfalls in Genitourinary Pathology: 2018 Update

Immunohistochemistry may be a very useful adjunct to morphologic diagnosis in many areas of surgical pathology, including genitourinary pathology. In this review, we address common diagnostic dilemmas where immunophenotypic analysis may be utilized and we highlight pitfalls specific to each scenario. For prostate, we review the diagnosis of limited prostatic adenocarcinoma and the distinction of high-grade prostatic adenocarcinoma from urothelial carcinoma. We also cover markers of urothelial lineage in the diagnosis of metastatic carcinoma of unknown primary site. In the kidney, distinction of poorly differentiated renal cell carcinoma from urothelial carcinoma and epithelioid angiomyolipoma, adjuncts to the recognition of hereditary renal neoplasia, and the diagnosis of metastatic renal cell carcinoma are discussed. Finally, for testis we address distinction of germ cell tumors from sex cord-stromal tumors, as well as the diagnosis of metastatic germ cell tumors.

P16 Expression in Extramammary Paget's Disease of the Vulva and Scrotum Is Not Human Papillomavirus Related

INTRODUCTION

Extramammary Paget disease (EMPD) of the vulva has been shown to express p16 by immunohistochemistry (IHC), however, p16 expression in the vulva and scrotum has not been extensively studied in relation to human papillomavirus (HPV) within EMPD of both the vulva and scrotum.

DESIGN

Twenty-two cases of EMPD (vulva, 16; scrotum, 6) were found in our laboratory information system. P16 and HPV IHC were performed. Any p16 reactivity less than 10% was considered negative. HPV in situ hybridization for both low- and high-risk HPV was also performed on all cases.

RESULTS

Of the 6 scrotal EMPD, 3 (50%) showed weak to moderate positive reactivity for p16 by IHC. Of the 16 vulvar EMPD, 13 (81%) were positive for p16, with at least moderate (2+) intensity with a mean expression of 33.3% (range = 10% to 80%) and 62% (range = 20% to 95%) in scrotal and vulvar EMPD, respectively. None of the scrotal or vulvar cases showed positive reactivity for HPV either by IHC or in situ hybridization.

CONCLUSION

Both vulvar and scrotal EMPD can express p16 by IHC, more commonly vulvar than scrotal; however, no HPV was detected either by IHC or in situ hybridization. EMPD of vulva and scrotum does not appear to be related to HPV, and p16 expression may be regulated through a different mechanism.

Secondary Malignancies of the Bladder: Avoiding the Diagnostic Pitfall

Although rare, secondary tumors of the bladder can present a diagnostic dilemma to pathologists considering a differential diagnosis of primary bladder cancer. We investigated the clinicopathologic and imaging characteristics of metastatic tumors to the bladder. We retrospectively reviewed the surgical pathology databases from 2 sites from 2013 to 2016, identifying 66 cases of secondary bladder tumors. Clinical, pathologic, and imaging findings were reviewed. Mean age at diagnosis was 63 years (range = 25-87). Females had a significantly higher proportion (44/66, 66.7%) of secondary bladder tumors compared with males (22/66, 33.3%; P = .007). In total, 56/66 (84.8%) patients had a clinical history of an in situ or invasive malignancy in another organ, and 54/66 (81.8%) patients had imaging supporting a metastatic tumor. Only 2/66 (3.0%) patients had a prior history of urothelial carcinoma. In total, 4/66 (6.1%) cases (all females) were originally misdiagnosed as primary bladder malignancies and were corrected after clinicoradiologic correlation. Overall, colorectal origin was most common (15/66, 22.7%), followed by cervical and ovarian primaries (10/66, 15.2% each). Cervical and ovarian origins predominated in the female cohort (10/44, 22.7% each), followed by endometrial (8/44, 18.2%). Colorectal and prostate primaries were the most common among males (10/22, 45.5%, and 7/22, 31.8%, respectively). Secondary bladder tumors can mimic urothelial carcinomas. In our cohort, gynecological, colorectal, and prostatic origins were most common. Clinical history, imaging, and immunohistochemical studies can be useful in avoiding this diagnostic pitfall.

Role of SATB2 in distinguishing the site of origin in glandular lesions of the bladder/urinary tract

The differential diagnosis of glandular lesions of the bladder/urinary tract can be challenging because of significant morphologic and immunohistochemical overlap between primary lesions and metastasis/direct extension from adjacent organs. Special AT-rich sequence-binding protein 2 (SATB2), encoded on chromosome 2q32-33, is a recently described DNA-binding protein involved in osteoblast lineage commitment and expressed in colorectal and appendiceal neoplasms. In this study, we hypothesized that immunohistochemistry for SATB2 may be of value in distinguishing primary adenocarcinoma of the bladder/urinary tract and urothelial carcinoma with glandular differentiation from gastrointestinal and endocervical primaries. Intensity and distribution of SATB2 nuclear labeling were semiquantitatively scored and compared with those of CDX2. The study included 43 primary adenocarcinomas of the bladder/urinary tract, 20 urothelial carcinomas with glandular differentiation, 26 adenocarcinomas of the uterine cervix, and 22 colorectal adenocarcinomas involving the bladder. Positive SATB2 immunostaining was observed in 21 of 43 (49%) primary bladder/urinary tract adenocarcinomas, in 17 of 22 (77%) colorectal adenocarcinomas, and in the glandular component of 4 of 18 (22%) urothelial carcinomas with glandular differentiation. SATB2 was negative in 25 of 26 endocervical adenocarcinomas and showed focal weak immunostaining (1+) in 1 of 26 (4%). The results were not significantly different from those seen with CDX2. We conclude that SATB2 immunohistochemistry is not useful in supporting urothelial versus gastrointestinal or endocervical origin in the differential diagnosis of glandular lesions of the bladder/urinary tract.

Non-invasive papillary urothelial carcinoma of the vagina: molecular analysis of a rare case identifies clonal relationship to non-invasive urothelial carcinoma of the bladder

We present a rare case of non-invasive papillary urothelial carcinoma of the vagina as the initial presentation of a multicentric urothelial carcinoma also involving bladder and renal pelvis and report for the first time in the literature the molecular alterations observed in the vaginal urothelial lesion and the synchronous lesions of the urinary tract. In this case, the non-invasive papillary urothelial carcinoma in the vagina displayed the same genetic alterations in the FGFR3 and PIK3CA genes as those seen in the non-invasive papillary urothelial carcinoma of the bladder contrasting with the wild phenotype observed in the invasive urothelial carcinoma of the renal pelvis. This observation could reinforce the theory of "seeding" of carcinoma cells as a valid and most likely explanation of this multifocality. In addition, we emphasize in this report the importance of recognizing this rare lesion in the female genital tract and its differential diagnosis.

Carcinoma of the Uterine Cervix Involving the Genitourinary Tract: A Potential Diagnostic Dilemma

Uterine cervical carcinoma secondarily involving the genitourinary tract is rarely documented histologically. These tumors present a unique diagnostic challenge as they can appear morphologically similar to urothelial carcinoma as well as primary squamous cell carcinoma and primary adenocarcinoma of the bladder. Genitourinary consult cases at the Johns Hopkins Hospital from 1984 to the present were searched for cases in which the differential diagnosis was primary bladder carcinoma versus secondary involvement by cervical carcinoma. We identified 10 cases that met these criteria and evaluated them by immunohistochemistry for p16 and GATA3 and in situ hybridization for human papillomavirus (HPV). Six cases were received with a gynecologic history. Four cases had been misdiagnosed as urothelial carcinoma, and 1 case was favored to be cystitis cystica et glandularis by the submitting institutions. Morphologically, the majority of cases showed basaloid nests of tumor cells infiltrating muscle bundles, with several having foci that mimicked urothelial carcinoma in situ. Six tumors were found to be diffusely positive with p16, 1 tumor was patchy, 1 was weak, and 2 were negative. GATA3 staining was negative in 6 cases, and 4 showed weak to strong positivity. Eight cases were positive for high-risk HPV (6 were positive for HPV 16, and 1 was positive for HPV 18). In the 2 cases that were negative for HPV by in situ hybridization, characteristic morphologic features of HPV-unrelated type of endocervical adenocarcinoma were present. On the basis of our findings we advocate a multifaceted approach, combining morphologic evaluation with ancillary studies including immunohistochemistry and in situ hybridization in the evaluation of genitourinary specimens for secondary involvement by cervical carcinoma. Furthermore, gynecologic clinical history is absolutely critical and most important to the evaluation and diagnosis of these specimens, as these ancillary studies are not completely sensitive or specific.

Human papilloma virus is not detectable in samples of urothelial bladder cancer in a central European population: a prospective translational study

Background

Previous investigations on the association of human papillomavirus (HPV) and human bladder cancer have led to conflicting results. The aim of this study was to determine if low and high risk HPV play a role in the etiology of superficial low grade and invasive high grade urothelial carcinoma of the bladder.

Methods

We prospectively collected tumor samples of urothelial carcinoma of the bladder from 109 patients treated with transurethral resection or cystectomy, with bladder tissue from transurethral resection of the prostate serving as control. Unfixed, frozen tumor samples were analyzed for the presence of 14 high risk HPV types using real time PCR. Additionally, all specimens were tested for 35 low risk HPV types with a conventional PCR using degenerate primers located in the L1 region. Six frozen samples of cervical carcinoma served as positive controls.

Results

We included 109 cases of bladder cancer with 41 superficial (pTa low grade) tumors, 56 invasive (pT1-T4) high grade tumors and 12 others (pTa high grade + pTis). We have not detected HPV-DNA in any sample (95 % Confidence Interval [CI] 0–3.3 %), superficial tumors (95 % CI 0–6.4 %) or in invasive tumors (95 % CI 0–8.6 %) with correct positive controls.

Conclusions

Using a broad, sensitive assay with prospectively collected specimens of a Central European population we could not detect HPV-DNA in any of the cases. Our results suggest that it is unlikely that HPV infections play a major role in the development of urothelial bladder cancer.

p16INK4A expression is frequently increased in periorbital and ocular squamous lesions

Background

p16 expression is a well established biomarker of cervical dysplasia and carcinoma arising from high risk human papilloma virus infection. Increased p16 expression is also seen in squamous neoplasms arising at other sites, including head, neck, and oropharyngeal tract. Squamous lesions are also frequently encountered at ocular surface and peri-orbital skin sites, but the prevalence of increased p16 expression in these lesions has been poorly studied.

Methods

We retrospectively surveyed 13 ocular surface and 16 orbital squamous lesions biopsied at UC San Diego Healthcare System and VA San Diego Healthcare System for p16 expression by immunohistochemistry. These cases included ocular surface lesions with diagnoses of conjunctival intraepithelial neoplasm (CIN) and squamous cell carcinoma in situ. Peri-orbital eyelid biopsies included lesions with diagnoses of SCCis and invasive squamous cell carcinoma. We performed multivariate logistic regression, followed by student’s T-test or Fisher's exact test to determine if there were statistically significant associations between p16 immunoreactivity and patient age, gender, diagnosis, and ethnicity. Statistical significance was defined as p < 0.05.

Results

We found an unexpectedly large prevalence of strong nuclear and cytoplasmic p16 immunoreactivity in our cases. Almost all of the ocular surface squamous lesions were diffusely positive for p16 expression (12/13). All of the periorbital lesions showed diffuse p16 immunoreactivity (16/16). Altogether, 28/29 lesions tested showed strong and diffuse p16 expression. We found no statistically significant correlation between p16 expression and patient age, gender, ethnicity, or diagnosis. In 6 of the peri-orbital biopsies, we had sufficient tissue to assess high-risk HPV expression by in situ hybridization. Interestingly, all of these cases were negative for HPV, despite strong p16 expression.

Conclusion

Strong p16 expression was observed in virtually all of the ocular surface and peri-orbital squamous neoplasms in our study. The relationship between p16 expression and HPV infection in ocular surface and peri-orbital sites requires further investigation.

Urothelial carcinoma with squamous differentiation--the pathologists׳ perspective

Squamous differentiation is the most common variant histology in urothelial carcinoma and may have effects on clinical outcome. Inconsistencies in reporting variant histologies in urothelial carcinoma are well documented. Immunohistochemical and molecular markers may help identify tumors with squamous differentiation beyond light microscopy.

Chronic inflammation in urothelial bladder cancer

The association between inflammation and cancer has been pointed out in epidemiological and clinical studies, revealing how chronic inflammation may contribute to carcinogenesis in various malignancies. However, the molecular events leading to malignant transformation in a chronically inflamed environment are not fully understood. In urothelial carcinoma of the urinary bladder, inflammation plays a dual role. On the one hand, chronic inflammation is a well-established risk factor for the development of bladder cancer (BC), as seen in Schistosoma haematobium infection. On the other, intravesical therapy by bacillus Calmette-Guérin (BCG), which induces inflammation, offers protection against cancer recurrence. The large variety of pro-inflammatory mediators expressed by BC and immune cells binds to specific receptors which control signalling pathways. These activate transcription of a plethora of downstream factors. This review summarizes recent data regarding inflammation and urothelial carcinoma, with special emphasis on the role the inflammatory response plays in BC recurrence risk and progression.

The Prognostic Impact of Histopathological Variants in Patients with Advanced Urothelial Carcinoma

Purpose

This study investigated the prognostic role of histopathological variants in patients with advanced urothelial carcinoma (UC) who were treated with systemic chemotherapy.

Materials and Methods

We conducted a retrospective analysis of patients with unresectable and/or metastatic UC who underwent systemic chemotherapy between January 1997 and December 2013 in Kaohsiung Chang Gung Memorial Hospital. Histopathological types were categorized as pure UC (PUC) and variants of UC (VUC). The overall survival (OS) and progression-free survival (PFS) were calculated using Kaplan–Meier analyses and Cox proportional regression models.

Results

A total of 206 patients were enrolled; 53 of the patients (25.7%) had histopathological variants. The most common variant was squamous differentiation (68%). Compared with patients with PUC, patients with VUC significantly exhibited upper urinary tract origin (75% vs 52%, P = .008), chronic renal insufficiency (40% vs 23%, P = .03), and carboplatin-based chemotherapy (28% vs 10%, P = .003). According to univariate analysis, the median OS for PUC patients was significantly higher than that for VUC patients (15.9 vs 11.3 months, P = .007). The median PFS for patients who received first-line chemotherapy was 6.1 and 3.8 months for PUC patients and VUC patients, respectively (P = .004). Multivariate analysis revealed that VUC (hazard ratio [HR] 1.67, 95% confidence interval [CI] 1.16–2.40, P = .006), an age ≤ 60 years (HR 0.70, 95% CI 0.49–0.99, P = .045) and presence of visceral metastasis (HR 1.54, 95% CI 1.11–2.13, P = .009) were independent factors facilitating OS prediction.

Conclusions

The presence of histopathological variants indicates poor survival outcomes in patients with metastatic UC. Accordingly, VUC should be integrated into and considered an independent factor in a predictive model of survival.

p16(INK4a) overexpression is not linked to oncogenic human papillomaviruses in patients with high-grade urothelial cancer cells

BACKGROUND

p16(INK4a) Is overexpressed in almost all precancerous and carcinomatous lesions of the uterine cervix, secondary to interference between high-risk human papillomaviruses (hr-HPVs) and the retinoblastoma gene product. Overexpression of p16(INK4a) has also been identified in patients with high-grade urothelial lesions, both cytologically and histologically. However, the etiological role of HPV has not been documented except in inverted papillomas, low-grade bladder tumors, and younger patients. We therefore attempted to verify if HPV DNA was detectable in p16(INK4a) -positive urothelial tumors.

METHODS

A total of 90 urinary cytology samples (33 negative/low-grade cases and 57 high-grade proliferations) were analyzed for p16(INK4a) and HPV DNA. HPV genotyping was performed by polymerase chain reaction using a low-density DNA microarray enabling the detection of 35 HPVs. A reasoned approach combining tissue genotyping and in situ hybridization (ISH) for hr-HPVs was used in patients with urinary HPV.

RESULTS

Low-risk HPV (HPV-84) and hr-HPVs (HPV-16, -31, and -70) were detected. The prevalence of hr-HPVs in the urine was low: 5 of 82 patients (6.1%) and only 4 of 50 patients (8.0%) with high-grade urothelial malignancy. p16(INK4a) overexpression was noted in 49 high-grade samples (85.9%). In patients with p16(INK4a) -positive tumor cells and hr-HPV in the urine, HPV genotyping and ISH for hr-HPVs were negative in matched tissue sections.

CONCLUSIONS

Our study shows a low prevalence of hr-HPVs in the urine of patients with high-grade urothelial malignancy. In those, p16(INK4a) overexpression occurs in the absence of demonstrable HPV DNA in the tissue sections, contrary to what is noted in gynecopathology.

HRAS mutations are frequent in inverted urothelial neoplasms

Inverted urothelial papilloma (IUP) is an uncommon neoplasm of the urinary bladder with distinct morphologic features. Studies regarding the role of human papillomavirus (HPV) in the etiology of IUP have provided conflicting evidence of HPV infection. In addition, little is known regarding the molecular alterations present in IUP or other urothelial neoplasms, which might demonstrate inverted growth pattern like low-grade or high-grade urothelial carcinoma (UCA). Here, we evaluated for the presence of common driving somatic mutations and HPV within a cohort of IUPs, (n = 7) noninvasive low-grade papillary UCAs with inverted growth pattern (n = 5), and noninvasive high-grade papillary UCAs with inverted growth pattern (n = 8). HPV was not detected in any case of IUP or inverted UCA by either in situ hybridization or by polymerase chain reaction. Next-generation sequencing identified recurrent mutations in HRAS (Q61R) in 3 of 5 IUPs, described for the first time in this neoplasm. Additional mutations of Ras pathway members were detected including HRAS, KRAS, and BRAF. The presence of Ras pathway member mutations at a relatively high rate suggests this pathway may contribute to pathogenesis of inverted urothelial neoplasms. In addition, we did not find any evidence supporting a role for HPV in the etiology of IUP.

HPV11 Positive Endometrioid Carcinoma of the Endometrium with Signet-Ring Cells: Diagnostic Criteria and Review of the Literature

The presence of signet-ring cells in an endometrial adenocarcinoma is extremely uncommon and it is always necessary to rule out a metastatic neoplasm. We report a FIGO grade 2 endometrial carcinoma with a signet-ring cell component found in the curettage performed to a 53-year-old woman. The neoplastic proliferation was also found in the endometrium of the radical hysterectomy with bilateral salpingo-oophorectomy and pelvic and para-aortic lymphadenectomy. The uterine neoplasm invaded less than one-half of the myometrium (FIGO stage I B). Alcian blue showed the presence of mucin in the signet-ring cells. The patient was alive and without evidence of recurrence 14 months after surgery. Polymerase chain reaction method from paraffin-embedded tissue revealed the presence of human papilloma virus type 11. We have discussed the differential diagnosis of this kind of neoplasm and we have reviewed the literature on signet-ring cell carcinoma of the endometrium.

Genotyping of high-risk human papillomaviruses in p16/Ki-67-positive urothelial carcinoma cells: even a worm will turn

OBJECTIVE

Co-expression of p16INK4a protein and Ki-67 (p16/Ki-67) is noted in almost all high-grade urothelial lesions. However, the aetiological role or, conversely, the absence of causative effect of high-risk human papillomaviruses (hr-HPVs) has not been documented. The purpose of this study is to evaluate HPV DNA in p16/Ki-67-positive, high-grade urothelial tumour cells.

METHODS

Fifty-seven urine samples collected from 50 patients, including 55 histologically proven high-grade proliferations and two cases with clinical evidence of malignancy, were analysed for p16/Ki-67. Immunolabelling was performed in destained Papanicolaou-stained slides after ThinPrep(®) processing. HPV genotyping was performed by polymerase chain reaction (PCR) using a DNA microarray for 35 HPV types. Confirmation of the presence (or absence) of HPV in tissue samples was verified using a reasoned approach combining PCR and in situ hybridization (ISH) for hr-HPVs.

RESULTS

Co-expression of p16/Ki-67 was noted in 43 of 57 (75.4%) cases. In these, hr-HPVs 16, 31 and 70, and low risk HPV 84, were detected in the urine in four patients (8%). Upregulation of p16INK4a protein was confirmed on bladder biopsy or transurethral resection specimens, but PCR and ISH for hr-HPVs were both negative on the tissue sections.

CONCLUSION

Our results show a low prevalence of HPV infection in the urinary tract of patients with p16/Ki-67-positive urothelial malignancy. The study confirms that the deregulated cell cycle, as demonstrated by p16/Ki-67 dual labelling, is independent of the oncogenic action of hr-HPVs in high-grade urothelial proliferations.

The expression patterns of p53 and p16 and an analysis of a possible role of HPV in primary adenocarcinoma of the urinary bladder

BACKGROUND

Primary adenocarcinoma of the urinary bladder is rare. The molecular and cellular events leading to its pathogenesis are not well delineated. The goal of this study was to investigate p53 and p16 expression, as well as HPV status, in a relatively large series of primary bladder adenocarcinomas.

MATERIALS AND METHODS

Thirty six cases of urinary bladder adenocarcinoma were chosen from participating institutions. The diagnosis and available clinical history were reviewed in each case. Immunostains for p53, p16 and HPV and high-risk and low-risk HPV-ISH were performed on all tumors.

RESULTS

Patients had an average age of 61 years with a male predominance (1.5 ∶ 1 male ∶ female ratio). The average tumor size in cystectomy specimens was 4.3 cm. Of the cases managed by transurethral resection, 40% were pT2 at the time of diagnosis. In cystectomy specimens, 77% were either pT3 or pT4. Strong nuclear p16 expression was seen in 67% of all cases and p53 expression was present in 58% of the cases. Expression of both markers was seen in 33% of cases. Expression of p16 or p53 alone was present in 12 (33%) and 9 (25%) cases, respectively. Neither marker was expressed in only 3 (8%) of the tumors. No significant correlation between clinical variables and any of the markers we studied was identified. No HPV infection was detected in any case.

CONCLUSIONS

Expression of p53 and/or p16 is very common in urinary bladder adenocarcinoma. These findings implicate a high likelihood that alterations in these cell cycle proteins contribute to the pathogenesis of these tumors. Despite frequent immunohistochemical labeling for p16, no evidence of HPV infection was found.

Detection of human papillomavirus infection and p16 immunohistochemistry expression in bladder cancer with squamous differentiation

OBJECTIVES

To determine the potential association between HPV infection and the squamous cell component of urothelial carcinoma (UC) of the bladder and to validate p16 overexpression as a surrogate marker for HPV infection in these cancers among Koreans.

METHODS

We analyzed the presence of HPV infection using an HPV-DNA chip and the expression of p16 using immunohistochemistry in 47 subjects between July 2001 and March 2011. The study group (n = 35) included patients with squamous differentiation of UC of the bladder. The control group (n = 12) included patients with squamous metaplasia of the bladder.

RESULTS

Baseline characteristics of control and study groups were similar. HPV DNA detection rates were approximately 2-fold higher in the study than the control group (17.1% [6/35] versus 8.3% [1/12], respectively), but the difference was not statistically significant. P16 overexpression was detected in 16/35 (45.7%) study group and 1/12 (8.3%) control group samples (p = 0.034). Both HPV-positivity and p16 overexpression were present in 3/35 (8.8%) study group samples, but none of the control group (p = 0.295). In the study group, the percentage of HPV-positive cases who were non-smokers was 2-fold higher than the percentage of HPV-negative cases who were non-smokers (66.7% [4/6] versus 31.0% [9/29], respectively); however, statistical significance was not achieved due to the small sample size.

CONCLUSIONS

HPV infection may be associated with UC of the bladder with squamous differentiation, especially in non-smokers. However, p16 expression does not appear to be a strong surrogate marker for evidence of HPV infection in this type of cancer.

Human papillomavirus is not an etiologic agent of urothelial inverted papillomas

Inverted papilloma of the urinary bladder is rare, accounting for <1% of all bladder neoplasms. Although there is general consensus that inverted papilloma is benign in nature, little is known about its pathogenesis. Some have suggested that human papillomavirus (HPV) plays an etiologic role in the development of this neoplasm. These claims have not been adequately substantiated, and there is controversy as to the role of HPV in other urinary bladder neoplasms as well. To further investigate a possible etiologic role of HPV in urothelial neoplasia, we evaluated 27 inverted papillomas of the urinary bladder for the presence of HPV. Both immunohistochemical and in situ hybridization (ISH) studies for HPV and immunohistochemical analysis for p16, a surrogate marker for HPV infection, were used to assess HPV infection status. In the urinary bladder inverted papillomas of these 27 patients (age range, 35 to 78 y; M:F ratio, 11:1), no HPV was detected by HPV immunohistochemistry or by ISH. Immunoreactivity to p16 was detected in 11/27 (41%) of the cases. Expression of p16 is seen inconsistently within these neoplasms and does not correlate with the presence of HPV antigens or genes by immunohistochemistry or ISH, respectively. Therefore, p16 is not a reliable surrogate marker for HPV infection in urothelial inverted papilloma. Our findings indicate the absence of HPV in urothelial inverted papillomas. HPV testing should not be used as a diagnostic adjunct for inverted papilloma cases.

Overexpression of p16(INK4a) in urothelial carcinoma in situ is a marker for MAPK-mediated epithelial-mesenchymal transition but is not related to human papillomavirus infection

BACKGROUND

The role of human papillomavirus (HPV) in bladder carcinogenesis remains controversial. Overexpression of p16(INK4a), a surrogate marker for infection with oncogenic HPV in other tumours, has been described for urothelial carcinoma in situ (UCIS). Our goal was therefore to evaluate whether overexpression of p16(INK4a) is associated with HPV infection and to identify mechanisms of p16(INK4a) upregulation in UCIS.

MATERIALS AND METHODS

In 60 tissue specimens from a total of 45 patients (UCIS and controls), we performed p16(INK4a) immunohistochemistry followed by detection and subclassification of HPV DNA. In a subset of samples, we tested for gene amplification of p16(INK4a) applying fluorescence in situ hybridization (FISH). RAS/MAPK signalling and epithelial-mesenchymal transition (EMT) was assessed using immunohistochemistry. Finally, we transfected urothelial carcinoma cells with KRAS and examined the expression of p16(INK4a) as well as markers of EMT.

RESULTS

We found overexpression of p16(INK4a) in 92.6% of UCIS and in all cervical intraepithelial neoplasia (CIN) controls. In contrast, we detected high-risk HPV DNA in 80% of CIN, but none in UCIS. There was no gene amplification of p16(INK4a). High levels of phosphorylated kinases and urokinase plasminogen activator (uPA) and loss of membraneous E-cadherin were detected in UCIS. KRAS transfection of urothelial carcinoma cells led to upregulation of p16(INK4a) and uPA accompanied by loss of E-cadherin that could be inhibited by application of the kinase-inhibitor Sorafenib.

CONCLUSIONS

Our results show that overexpression of p16(INK4a) in UCIS is neither associated with HPV infection nor p16(INK4a) gene amplification but is a consequence of enhanced RAS/MAPK signalling that promotes EMT, possibly due to Sorafenib-sensitive paracrine secretion of the EMT activator uPA. These findings might open a novel therapeutic option for localized but aggressive urothelial cancer.

Association of human herpes, papilloma and polyoma virus families with bladder cancer

The aim of the present study was to assess the possible etiologic role of human papillomavirus (HPV), human herpes virus (HHV) and the human polyoma virus families (BKV and JCV) in the tumourigenesis of bladder cancer. Thirty biopsy specimens from patients with different grades and stages of bladder cancer, who underwent transurethral bladder cancer resection, and 30 normal bladder mucosa specimens were analysed using polymerase chain reaction (PCR) for the detection of the above three virus family members. The presence of HPV was determined in all specimens with nested PCR and real-time quantitative PCR. All cancerous specimens, including the control group, were found to be negative both by PCR and real-time qPCR for the presence of HPV DNA, whilst all samples examined by PCR tested negative for the presence of HSV-1,2 Varicella zoster virus and HSV-7 DNA. Cytomegalovirus, HHV-6 and HHV-8 exhibited similar incidence in sample positivity in both cancerous and healthy tissues. EBV showed a higher prevalence in bladder cancer specimens compared to healthy tissue (p = 0.048), whilst BKV and JCV were detected only in tumour samples. The presence of EBV in a significant proportion of bladder tumours indicates the etiological role of this virus in cancer tumourigenesis.