Human papillomavirus prevalence in invasive penile cancer and association with clinical outcome

Prevalence of human papillomavirus DNA and p16INK4a in penile cancer and penile intraepithelial neoplasia: a systematic review and meta-analysis

BACKGROUND

Although previous meta-analyses have examined human papillomavirus (HPV) DNA prevalence in penile cancer, none, to our knowledge, have assessed pooled HPV DNA prevalence in penile intraepithelial neoplasia or p16^INK4a percent positivity in penile cancer and penile intraepithelial neoplasia. Therefore, we aimed to examine the prevalence of HPV DNA and p16^INK4a positivity in penile cancer and penile intraepithelial neoplasia worldwide.

METHODS

In this systematic review and meta-analysis, we searched PubMed, Embase, and the Cochrane Library until July 24, 2017, for English-language articles published from Jan 1, 1986, onwards reporting the prevalence of HPV DNA and p16^INK4a positivity, either alone or in combination, in at least five cases of penile cancer or penile intraepithelial neoplasia. Only studies that used PCR or hybrid capture for the detection of HPV DNA and immunohistochemical staining or methylation for the detection of p16^INK4a were included. Data were extracted and subsequently crosschecked, and inconsistencies were discussed to reach consensus. Using random-effects models, we estimated the pooled prevalence and 95% CI of HPV DNA and p16^INK4a positivity in penile cancer and penile intraepithelial neoplasia, stratifying by histological subtype and HPV DNA or p16^INK4a detection method. Type-specific prevalence of HPV6, HPV11, HPV16, HPV18, HPV31, HPV33, and HPV45 in penile cancer was estimated.

FINDINGS

Our searches identified 1836 non-duplicate records, of which 73 relevant papers (71 studies) were found to be eligible. The pooled HPV DNA prevalence in penile cancer (52 studies; n=4199) was 50·8% (95% CI 44·8-56·7; I²=92·6%, p_{heterogeneity}<0·0001). A high pooled HPV DNA prevalence was seen in basaloid squamous cell carcinomas (84·0%, 95% CI 71·0-93·6; I²=48·0%, p_{heterogeneity}=0·0197) and in warty-basaloid carcinoma (75·7%, 70·1-81·0; I²=0%, p_{heterogeneity}=0·52). The predominant oncogenic HPV type in penile cancer was HPV16 (68·3%, 95% CI 58·9-77·1), followed by HPV6 (8·1%, 4·0-13·7) and HPV18 (6·9%, 2·9-12·4). The pooled HPV DNA prevalence in penile intraepithelial neoplasia (19 studies; n=445) was 79·8% (95% CI 69·3-88·6; I²=83·2%, p_{heterogeneity}<0·0001). The pooled p16^INK4a percent positivity in penile cancer (24 studies; n=2295) was 41·6% (95% CI 36·2-47·0; I²=80·6%, p_{heterogeneity}<0·0001), with a high pooled p16^INK4a percent positivity in HPV-related squamous cell carcinoma (85·8%, 95% CI 72·1-95·4; I²=56·4%, p_{heterogeneity}=0·0011) as compared with non-HPV-related squamous cell carcinoma (17·1%, 7·9-29·1; I²=78·3%, p_{heterogeneity}<0·0001). Moreover, among HPV-positive cases of penile cancer, the p16^INK4a percent positivity was 79·6% (95% CI 65·7-90·7; I²=89·9%, p_{heterogeneity}<0·0001), compared with 18·5% (9·6-29·6; I²=89·3%, p_{heterogeneity}<0·0001) in HPV-negative penile cancers. The pooled p16^INK4a percent positivity in penile intraepithelial neoplasia (six studies; n=167) was 49·5% (95% CI 18·6-80·7).

INTERPRETATION

A large proportion of penile cancers and penile intraepithelial neoplasias are associated with infection with HPV DNA (predominantly HPV16), emphasising the possible benefits of HPV vaccination in men and boys.

FUNDING

None.

The Prognostic Value of PIK3CA Copy Number Gain in Penile Cancer

OBJECTIVE

To determine whether phosphatidylinositol-4,5-bisphosphate 3- kinase, catalytic subunit alpha (PIK3CA) copy number gain in penile cancer has prognostic value and association with histopathological parameters, human papillomavirus (HPV), and clinical outcome.

METHODS

PIK3CA copy number status was assessed with fluorescence in situ hybridization in tissue microarrays generated from archival paraffin embedded blocks of 199 patients with primary penile squamous cell carcinoma (PSCC). HPV DNA was detected with INNO-LiPA assay. Follow-up data were available for 174 patients. PIK3CA copy number status was correlated with histopathological parameters, high-risk HPV, cancer-specific survival and time to recurrence.

RESULTS

PIK3CA copy number gain was found in 84/199 (42%) of penile cancer cases. PIK3CA copy number gain was associated with tumor subtype, grade, and stage (P = .0028, P < .0001, and P = .0397, respectively), but not with lymph node status (P = .2902). PIK3CA copy number gain showed a tendency to associate with cancer-specific survival (HR = 1.76, 95% CI; 0.94-3.3; P = .0753). In multivariate analysis, PIK3CA copy number gain was found to have no prognostic value for cancer-specific survival (P = .677). Only lymph node metastasis, high tumor grade and stage were found to be independent prognostic factors for cancer-specific survival.

CONCLUSION

PIK3CA copy number gain could be used as a marker of high-risk disease as it correlates with more aggressive PSCC histological subtypes and higher tumor grade and stage. However, it shows no significant association with lymph node metastasis or prognostic value for cancer-specific survival in PSCC.

Human papillomavirus (HPV) genotype distribution in penile carcinoma: Association with clinic pathological factors

Background

Penile carcinoma (PC) is a rare, highly mutilating disease, common in developing countries. The evolution of penile cancer includes at least two independent carcinogenic pathways, related or unrelated to HPV infection.

Objectives

To estimate the prevalence, identify HPV genotypes, and correlate with clinicopathological data on penile cancer.

Methods

A retrospective cohort study involving 183 patients with PC undergoing treatment in a referral hospital in Goiânia, Goiás, in Midwestern Brazil, from 2003 to 2015. Samples containing paraffin embedded tumor fragments were subjected to detection and genotyping by INNO-LiPA HPV. The clinicopathological variables were subjected to analysis with respect to HPV positivity and used prevalence ratio (PR), adjusted prevalence ratio (PRa) and 95% confidence interval (CI) as statistical measures.

Results

The prevalence of HPV DNA in PC was 30.6% (95% CI: 24.4 to 37.6), high-risk HPV 24.9% (95% CI: 18.9 to 31.3), and 62.5% were HPV 16. There was a statistical association between the endpoints HPV infection and HPV high risk, and the variable tumor grade II-III (p = 0.025) (p = 0.040), respectively. There was no statistical difference in disease specific survival at 10 years between the HPV positive and negative patients (p = 0.143), and high and low risk HPV (p = 0.325).

Conclusions

The prevalence of HPV infection was 30.6%, and 80.3% of the genotypes were identified as preventable by anti-HPV quadrivalent or nonavalent vaccine. HPV infections and high-risk HPV were not associated with penile carcinoma prognosis in this study.

The Prognostic Value of Immune Factors in the Tumor Microenvironment of Penile Squamous Cell Carcinoma

The host's immune system plays a pivotal role in many tumor types, including squamous cell carcinomas (SCCs). We aim to identify immunological prognosticators for lymph node metastases (LNM) and disease-specific survival (DSS) in penile SCC. For this retrospective observational cohort study, penile SCC patients (n = 213) treated in the Netherlands Cancer Institute, were selected if sufficient formalin-fixed, paraffin-embedded tumor material was available. Analysis included previously described high-risk human papilloma virus (hrHPV) status, immunohistochemical scores for classical and non-classical human leukocyte antigen (HLA) class I, programmed death ligand-1 (PD-L1) expression, and novel data on tumor-infiltrating macrophages and cytotoxic an regulatory T-cells. Clinicopathological characteristics and extended follow-up were also included. Regression analyses investigated relationships of the immune parameters with LNM and DSS. In the total cohort, diffuse PD-L1 tumor-cell expression, CD163+ macrophage infiltration, non-classical HLA class I upregulation, and low stromal CD8+ T-cell infiltration were all associated with LNM. In the multivariable model, only tumor PD-L1 expression remained a significant predictor for LNM (odds ratio (OR) 2.8, p = 0.05). hrHPV negativity and diffuse PD-L1 tumor-cell expression were significantly associated with poor DSS and remained so upon correction for clinical parameters [hazard ratio (HR) 9.7, p < 0.01 and HR 2.8, p = 0.03]. The only immune factor with different expression in HPV+ and HPV- tumors was PD-L1, with higher PD-L1 expression in the latter (p = 0.03). In the HPV- cohort (n = 158), LNM were associated with diffuse PD-L1 tumor-cell expression, high intratumoral CD163+ macrophage infiltration, and low number of stromal CD8+ T-cells. The first two parameters were also linked to DSS. In the multivariable regression model, diffuse PD-L1 expression remained significantly unfavorable for DSS (HR 5.0, p < 0.01). These results emphasize the complexity of the tumor microenvironment in penile cancer and point toward several possible immunotherapy targets. Here described immune factors can aid risk-stratification and should be evaluated in clinical immunotherapy studies to ultimately lead to patient tailored treatment.

Current Management Strategy for Penile Cancer and Future Directions

PURPOSE OF REVIEW

The aim of this review is to evaluate the trends in multidisciplinary management of localized penile cancer and systemic therapy for advanced disease in the evolving era of targeted and immune checkpoint therapy.

RECENT FINDINGS

Organ preservation (surgical or incorporating radiation) and reconstructive techniques are important considerations for quality of life in penile cancer survivors. Although local recurrence may be higher with organ preservation, salvage therapy appears successful. Inguinal and pelvic node management requires multidisciplinary care, including chemotherapy; optimal use of radiation has not been fully defined. Advanced in understanding the biology of penile cancer, particularly with regard to epidermal growth factor receptor (EGFR) and HPV status, have led to clinical trials of targeted and immune therapy for patients with refractory disease. Refinements in the management of penile cancer are occurring, though level 1 evidence remains scarce. Referral to specialized centers will facilitate successful completion of clinical trials to advance standard care in this disease.

The high-risk HPV infection and urinary system tumor

HPV is classified into high-risk and low-risk types depending on its probability of leading to tumorigenesis. Many studies have shown that HPV infection, especially the infection caused by the high-risk type, is always related to prostate cancer, bladder cancer, penile cancer, testicular cancer, and other urinary system tumors. However, previous studies differed in sexual openness and racial genetic susceptibility of the study object, sample size, and experimental methods. Hence, the correlation between high-risk HPV infection and urinary system tumors remains controversial. The early open reading frame of the HPV genome is composed of E1–E7, among which E6 and E7 are the key transfer proteins. The combination of these proteins with oncogene and anti-oncogene may be one of the mechanisms leading to tumorigenesis.

Radiotherapy approaches for locally advanced penile cancer: neoadjuvant and adjuvant

PURPOSE OF REVIEW

As penile cancer is an uncommon malignancy in the Western society, randomized trials to address the controversies in management have not previously been undertaken. The incorporation of multidisciplinary approaches in the management of advanced penile carcinoma has largely borrowed evidence from analogous malignancies in the anogenital region. This review is being undertaken in preparation for the international launch of InPACT, the International Penile Advanced Cancer Trial, a collaborative effort from European and North American trialists.

RECENT FINDINGS

The literature supporting the development of this trial is reviewed, along with the trial design, goals, and endpoints. Level one evidence of the benefits of combined chemo-radiotherapy in the management of squamous cell carcinoma of the cervix, oropharynx, vulva, and anal canal has led to the introduction of this approach for advanced penile cancer. InPACT will compare chemo-radiotherapy to the traditional surgical approach, with or without neoadjuvant chemotherapy.

SUMMARY

InPACT will define the roles and optimal sequencing of surgery, chemotherapy, and radiotherapy in advanced penile cancer. In the meantime, this collaborative effort among the major research consortiums of Europe and North America lends credibility to the application of this evidence to the penile site.

Human Papillomavirus Type 16 Integration Analysis by Real-time PCR Assay in Associated Cancers

Human papillomavirus (HPV) is a common viral infection worldwide associated with a variety of cancers. The integration of the HPV genome in these patients causes chromosomal instability and triggers carcinogenesis. The aim of this study was to investigate the HPV-16 genome physical status in four major cancers related to HPV infection. Formalin-fixed paraffin-embedded blocks from our previous projects on head and neck, colorectal, penile, and cervical cancers were collected, and HPV-16–positive specimens were used for further analysis. The DNA extraction copy number of E2 and E7 genes was calculated by qualitative real-time PCR method. Serially diluted standards that were cloned in PUC57 plasmid were used. Standard curve and melting curve analysis was used for quantification. Of the 672 specimens studied, 76 (11.3%) were HPV-16 positive. We found that 35.6% (16/45) were integrated. Statistical analysis showed that there were significant correlations between integration of HPV-16 and cervical cancer end-stage carcinogenesis (P < .0001), episomal form, and ASCUS lesions (P = .045). Significant correlation in penile cancer patients was seen between the episomal form and high-grade cancer stage (P = .037). Integration is a major factor in the carcinogenesis mechanism of HPV and has different prevalence in various cancers with a higher rate in progression except in penile cancer.

The World Health Organisation 2016 classification of penile carcinomas: a review and update from the International Society of Urological Pathology expert-driven recommendations

The International Society of Urological Pathology (ISUP) held an expert-driven penile cancer conference in Boston in March 2015, which focused on the new World Health Organisation (WHO) classification of penile cancer: human papillomavirus (HPV)-related tumours and histological grading. The conference was preceded by an online survey of the ISUP members, and the results were used to initiate discussions. Because of the rarity of penile tumours, this was not a consensus but an expert-driven conference aimed at assisting pathologists who do not see these tumours on a regular basis. After a justification for the novel separation of penile squamous cell carcinomas into HPV-related and non-HPV-related-carcinomas, the histological classification of penile carcinoma was proposed; this system was also accepted subsequently by the WHO for subtyping of penile carcinomas (2016). A description of HPV-related neoplasms, which may be recognised by their histological features, was presented, and p16 was recommended as a surrogate indicator of HPV. A three-tier grading system was recommended for penile squamous carcinomas; this was also adopted by the WHO (2016). Many of the distinctive histological subtypes of squamous cell carcinoma of the penis are associated with distinct grades, based on the squamous cell carcinoma subtype histological features.

Insight into novel biomarkers in penile cancer: Redefining the present and future treatment paradigm?

INTRODUCTION

Biomarkers are increasingly used in the diagnosis and management of various malignancies. Selected biomarkers may also play a role in management of certain cases of penile carcinoma. In this article, we provide an overview of the clinical role of such markers in the management of penile cancer.

METHOD

This is a nonsystematic review of relevant literature assessing biomarkers in penile carcinoma.

RESULTS

Evidence of infections with human papillomavirus and its surrogate markers may have important prognostic value in patients with localized or metastatic penile cancer. Squamous cell carcinoma antigen, p53, C-reactive protein, Ki-67, proliferating cell nuclear antigen, cyclin D1, as well as other markers have been studied with various degree of evidence in support of clinical utility in penile cancer.

CONCLUSIONS

No single marker may have all the answers, and future research should focus on genomic analysis of individual penile tumors, attempting to identify specific targets for treatment.

Contemporary role of radiotherapy in the management of penile cancer

Penile cancer is a rare clinical entity that contributes to significant patient morbidity and mortality. Human papilloma virus (HPV) plays an important role in the carcinogenesis of penile squamous cell carcinoma (SCC), is associated with improved clinical outcomes, and is predictive for response to treatment with chemotherapy and radiotherapy. Historically, treatment consisted of radical surgery with partial or total penectomy. While effective for local control, surgical resection can impart significant physical, psychological and sexual dysfunction for afflicted men. Organ preservation strategies offer significant quality of life advantages over standard surgery and can be utilized without compromising oncological control. As an alternative or adjunct to surgical resection, radiation therapy can be used for organ preservation strategies successfully in up to 70% of patients. A variety of treatment techniques can be employed depending on the location and burden of disease. Limited disease can be amenable to treatment with interstitial brachytherapy, surface mold plesiotherapy or external beam radiotherapy. For locally advanced presentations, or for patients not amenable to surgical resection, excellent clinical outcomes can be achieved using a combination of chemotherapy and radiation therapy. Here, we discuss the management of penile SCC using modern radiation therapy treatment techniques, the expected clinical outcomes for organ preservation, as well as the management of side-effects and toxicities. While large randomized trials are being developed, the management of penile cancer is informed from the management of other of other anogenital malignancies, which we also review.

Relationship between human papillomavirus and penile cancer-implications for prevention and treatment

Penile cancer is a rare disease in the United States, but rates are increasing, causing concern. Several risk factors have been associated with the disease, including human papillomavirus (HPV) infection. Knowledge of HPV pathogenesis has led to the development of a vaccine, which has proven instrumental in reducing the incidence of female HPV-related cancers, but results in men have yet to be elucidated. Fortunately, rates of vaccination are up-trending in both males and females in the past several years. In addition, targeted therapies are the focus of several ongoing research efforts. Some of these therapeutics are currently in use, while several are in trials. With continued patient education and research, both treatment and prevention of HPV-related pre-malignant lesions and penile cancer will likely diminish.

Health and Economic Impact of a Tender-Based, Sex-Neutral Human Papillomavirus 16/18 Vaccination Program in the Netherlands

Background

Uptake of human papillomavirus (HPV) vaccine among girls in the Dutch immunization program has plateaued at around 60%. Vaccinating boys may be an appealing complementary strategy for the prevention of HPV-related diseases, especially since tender negotiations and reduced dosing schemes have driven down the cost of vaccination.

Methods

We expanded a previously published Bayesian synthesis framework to account for all vaccine type-related cancers and herd immunity effects from vaccinating girls and boys. We evaluated the efficiency of vaccinating boys relative to increasing vaccine uptake among girls and assessed the cost-effectiveness of a sex-neutral program.

Results

Vaccinating 40% of boys along with 60% of girls yielded the same gain in life-years (LYs) as increasing the uptake in girls from 60% to 80%. The incremental cost-effectiveness ratio (ICER) of vaccinating boys was €9134/LY (95% credible interval [CrI], €7323/LY-€11231/LY) under 3% discounting. The ceiling vaccination costs at which the ICER remained below the per capita gross domestic product threshold was €240 (95% CrI, €200-€280) per vaccinated boy. If girls' uptake increased to 90%, the ceiling costs decreased to €70 (95% CrI, €40-€100) per vaccinated boy.

Conclusions

Vaccinating boys along with girls is only modestly less efficient than increasing uptake among girls and highly likely to be cost-effective under current vaccine costs and uptake in the Netherlands.

Human Papillomavirus (HPV) Genotypes in Condylomas, Intraepithelial Neoplasia, and Invasive Carcinoma of the Penis Using Laser Capture Microdissection (LCM)-PCR: A Study of 191 Lesions in 43 Patients

Laser capture microdissection-polymerase chain reaction (LCM-PCR) supported by p16 was used for the first time to demonstrate human papillomavirus (HPV) DNA in histologically specific penile lesions, which were as follows: squamous hyperplasia (12 lesions, 10 patients), flat lesions (12 lesions, 5 patients), condylomas (26 lesions, 7 patients), penile intraepithelial neoplasia (PeIN) (115 lesions, 43 patients), and invasive squamous cell carcinomas (26 lesions, 26 patients). HPV was detected by whole-tissue section and LCM-PCR. LCM proved to be more precise than whole-tissue section in assigning individual genotypes to specific lesions. HPV was negative or very infrequent in squamous hyperplasia, differentiated PeIN, and low-grade keratinizing variants of carcinomas. HPV was strongly associated with condylomas, warty/basaloid PeIN, adjacent flat lesions, and warty/basaloid carcinomas. A single HPV genotype was found in each lesion. Some condylomas and flat lesions, especially those with atypia, were preferentially associated with high-risk HPV. Unlike invasive carcinoma, in which few genotypes of HPV were involved, there were 18 HPV genotypes in PeIN, usually HPV 16 in basaloid PeIN but marked HPV heterogeneity in warty PeIN (11 different genotypes). Variable and multiple HPV genotypes were found in multicentric PeIN, whereas unicentric PeIN was usually related to a single genotype. There was a correspondence among HPV genotypes in invasive and associated PeIN. p16 was positive in the majority of HPV-positive lesions except condylomas containing LR-HPV. p16 was usually negative in squamous hyperplasia, differentiated PeIN, and low-grade keratinizing variants of squamous cell carcinomas. In summary, we demonstrated that LCM-PCR was a superior research technique for investigating HPV genotypes in intraepithelial lesions. A significant finding was the heterogeneity of HPV genotypes in PeIN and the differential association of HPV genotypes with subtypes of PeIN. The presence of atypia and high-risk HPV in condylomas and adjacent flat lesions suggests a precursor role, and the correspondence of HPV genotypes in invasive carcinomas and associated PeIN indicates a causal relation. Data presented support the bimodal hypothesis of penile cancer carcinogenesis in HPV-driven and non-HPV-driven carcinomas and justify the current WHO pathologic classification of PeIN in special subtypes.

Integrative miRNA and mRNA analysis in penile carcinomas reveals markers and pathways with potential clinical impact

Penile carcinoma (PeCa) is an important public health issue in poor and developing countries, and has only recently been explored in terms of genetic and epigenetic studies. Integrative data analysis is a powerful method for the identification of molecular drivers involved in cancer development and progression. miRNA and mRNA expression profiles followed by integrative analysis were investigated in 23 PeCa and 12 non-neoplastic penile tissues (NPT). Expression levels of eight miRNAs and 10 mRNAs were evaluated in the same set of samples used for microarray and in a validation set of cases (PeCa = 36; NPT = 27). Eighty-one miRNAs and 2,697 mRNAs were identified as differentially expressed in PeCa. Integrative data analysis revealed 255 mRNAs potentially regulated by 68 miRNAs. Using RT-qPCR, eight miRNAs and nine transcripts were confirmed as altered in PeCa. We identified that MMP1, MMP12 and PPARG and hsa-miR-31-5p, hsa-miR-224-5p, and hsa-miR-223-3p were able to distinguish tumors from NPT with high sensitivity and specificity. Higher MMP1 expression was detected as a better predictor of lymph node metastasis than the clinical-pathological data. In addition, PPARG and EGFR were highlighted as potential pathways for targeted therapy in PeCa. The analysis based on HPV positivity (7 of 23 cases) revealed five miRNA and 13 mRNA differentially expressed. Although in a limited number of cases, HPV positive PeCa presented less aggressive phenotype in comparison with negative cases. Overall, an integrative analysis using mRNA and miRNA profiles revealed markers related with tumor development and progression. Furthermore, MMP1 expression level was a predictive marker for lymph node metastasis in patients with PeCa.

Somatic Host Cell Alterations in HPV Carcinogenesis

High-risk human papilloma virus (HPV) infections cause cancers in different organ sites, most commonly cervical and head and neck cancers. While carcinogenesis is initiated by two viral oncoproteins, E6 and E7, increasing evidence shows the importance of specific somatic events in host cells for malignant transformation. HPV-driven cancers share characteristic somatic changes, including apolipoprotein B mRNA editing catalytic polypeptide-like (APOBEC)-driven mutations and genomic instability leading to copy number variations and large chromosomal rearrangements. HPV-associated cancers have recurrent somatic mutations in phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) and phosphatase and tensin homolog (PTEN), human leukocyte antigen A and B (HLA-A and HLA-B)-A/B, and the transforming growth factor beta (TGFβ) pathway, and rarely have mutations in the tumor protein p53 (TP53) and RB transcriptional corepressor 1 (RB1) tumor suppressor genes. There are some variations by tumor site, such as NOTCH1 mutations which are primarily found in head and neck cancers. Understanding the somatic events following HPV infection and persistence can aid the development of early detection biomarkers, particularly when mutations in precancers are characterized. Somatic mutations may also influence prognosis and treatment decisions.

Clear Cell Carcinoma of the Penis: An HPV-related Variant of Squamous Cell Carcinoma: A Report of 3 Cases

Penile clear cell carcinoma originating in skin adnexal glands has been previously reported. Here, we present 3 morphologically distinctive penile tumors with prominent clear cell features originating not in the penile skin but in the mucosal tissues of the glans surface squamous epithelium. Clinical and pathologic features were evaluated. Immunohistochemical stains were GATA3 and p16. Human papilloma virus (HPV) detection by in situ hybridization was performed in 3 cases, and whole-tissue section-polymerase chain reaction was performed in 1 case. Patients' ages were 52, 88, and 95 years. Tumors were large and involved the glans and coronal sulcus in all cases. Microscopically, nonkeratinizing clear cells predominated. Growth was in solid nests with comedo-like or geographic necrosis. Focal areas of invasive warty or basaloid carcinomas showing in addition warty or basaloid penile intraepithelial neoplasia were present in 2 cases. There was invasion of corpora cavernosa, lymphatic vessels, veins, and perineural spaces in all cases. p16 was positive, and GATA3 stain was negative in the 3 cases. HPV was detected in 3 cases by in situ hybridization and in 1 case by polymerase chain reaction. Differential diagnoses included other HPV-related penile carcinomas, skin adnexal tumors, and metastatic renal cell carcinoma. Features that support primary penile carcinoma were tumor location, concomitant warty and/or basaloid penile intraepithelial neoplasia, and HPV positivity. Clinical groin metastases were present in all cases, pathologically confirmed in 1. Two patients died from tumor dissemination at 9 and 12 months after penectomy. Clear cell carcinoma, another morphologic variant related to HPV, originates in the penile mucosal surface and is probably related to warty carcinomas.

Human Papillomavirus

Individuals with inherited immunodeficiencies, autoimmune disorders, organ or bone marrow transplantation, or infection with human immunodeficiency virus (HIV) are at increased risk of infection with both low-risk and high-risk human papillomavirus (HPV) types. Chronic immunosuppression provides an environment for persistent HPV infection which carries a higher risk of malignant transformation. Screening guidelines have been developed or advocated for processes that have detectable premalignant lesions, such as anal cancer or cervical cancer. For other anatomic locations, such as cutaneous, penile, and oropharyngeal, a biopsy of suspicious lesions is necessary for diagnosis. HPV cannot be cultured from clinical specimens in the laboratory, and diagnosis relies on cytologic, histologic, or molecular methods.

Comparison of the Natural History of Genital HPV Infection among Men by Country: Brazil, Mexico, and the United States

Background: Male genital human papillomavirus (HPV) prevalence and incidence has been reported to vary by geographical location. Our objective was to assess the natural history of genital HPV by country among men with a median of 48 months of follow-up.Methods: Men ages 18-70 years were recruited from United States (n = 1,326), Mexico (n = 1,349), and Brazil (n = 1,410). Genital specimens were collected every 6 months and HPV genotyping identified 37 HPV genotypes. Prevalence of HPV was compared between the three countries using the Fisher exact test. Incidence rates and 95% confidence intervals were calculated. The median time to HPV clearance among men with an incident infection was estimated using the Kaplan-Meier method.Results: The prevalence and incidence of the genital HPV types known to cause disease in males (HPV 16 and 6) was significantly higher among men from Brazil than men from Mexico. Prevalence and incidence of those genital HPV types in the United States varied between being comparable with those of Mexico or Brazil. Although genital HPV16 duration was significantly longer in Brazil (P = 0.04) compared with Mexico and the United States, HPV6 duration was shortest in Brazil (P = 0.03) compared with Mexico and the United States.Conclusions: Men in Brazil and Mexico often have similar, if not higher prevalence of HPV compared with men from the United States.Impact: Currently, there is no routine screening for genital HPV among males and while HPV is common in men, and most naturally clear the infection, a proportion of men do develop HPV-related diseases. Men may benefit from gender-neutral vaccine policies. Cancer Epidemiol Biomarkers Prev; 26(7); 1043-52. ©2017 AACR.

Country-specific HPV-related genital disease among men residing in Brazil, Mexico and The United States: The HIM study

The purpose of this study was to assess whether the incidence of histopathologically confirmed condyloma and penile intraepithelial neoplasia (PeIN) and rates of genital HPV infection progression to these lesions differs by country (Brazil, Mexico and the U.S.). At each visit, lesions were biopsied and were categorized by pathologic diagnoses. The Linear Array genotyping method was used to identify HPV genotypes from genital swabs, while the INNO-LiPA HPV Genotyping Extra method was used for tissue specimens. Age-specific analyses were conducted for lesion incidence by country, with Kaplan-Meier estimation of cumulative incidence. The proportion of HPV infections that progressed to condyloma and PeIN, the median time to lesion development and the incidence rates were estimated by country. When comparing demographic and sexual characteristics across the three countries, sexual orientation (p = 0.008) and lifetime number of female sexual partners (p < 0.0001) were differentially associated with lesion incidence in the three countries. Condyloma incidence in Brazil and the U.S. decreased with age, while incidence remained constant across the lifespan in Mexico. There were no differences by country and age for PeIN incidence. HPV types 6 and 11 were the most common types to progress to condyloma and HPV types 16, 6 and 11 were the most common types to progress to PeIN in all three countries. The continuous risk of condyloma and PeIN across all age groups and countries in this study emphasizes the need to ensure that strong HPV immunity, such as that obtained through vaccination, is maintained across the lifespan of men.

New Developments and Challenges in Rare Genitourinary Tumors: Non-Urothelial Bladder Cancers and Squamous Cell Cancers of the Penis

The diagnosis and treatment of rare genitourinary tumors is inherently challenging. The Rare Diseases Act of 2002 initially defined a rare disorder as one that affects fewer than 200,000 Americans. The lack of widely available clinical guidelines, limited research funding, and inaccessible clinical trials often lead to difficulty with treatment decisions to guide practitioners in rendering effective care for patients with rare genitourinary cancers. This article will discuss basic tenets of diagnosis and treatment as well as recent developments and clinical trials in rare non-urothelial bladder cancers and penile squamous cell cancers.

Pathophysiological basis of human papillomavirus in penile cancer: Key to prevention and delivery of more effective therapies

Answer questions and earn CME/CNE Squamous cell carcinoma (SCC) of the penis is a rare malignancy in the United States, with a significantly higher incidence-up to 20 to 30 times greater-in areas of Africa and South America. This can be explained in part by the significantly greater prevalence of sexually transmitted diseases among high-risk males often having unprotected sex with multiple sexual partners. Human papillomavirus (HPV) has been implicated as the infectious pathway by which several these penile neoplasms originate from precursor lesions. In this regard, a fundamental understanding of HPV in penile carcinogenesis can have meaningful implications in understanding 1) the diagnosis of HPV-related precursor penile lesions, 2) targeting HPV-specific molecular pathways, and 3) cancer prevention. Using vaccination programs not only may improve patient outcomes but also may minimize the need for highly aggressive and often debilitating surgical resection. CA Cancer J Clin 2016;66:481-495. © 2016 American Cancer Society.

Expression of Programmed Death Ligand 1 in Penile Cancer is of Prognostic Value and Associated with HPV Status

PURPOSE

PD-L1 (programmed death ligand 1) inhibits T-cell function and prevents tumor eradication. This is facilitated by PD-L1 positive tumor cells and PD-L1 positive immune cells, and can be prevented by anti-PD-1 (programmed death 1)/PD-L1 immunotherapy. In advanced penile cancer there is a need for new therapeutic strategies. We investigated PD-L1 expression in penile cancers and compared PD-L1 expression with disease specific survival, lymph node metastases at diagnosis and high risk HPV status in a large patient cohort.

MATERIALS AND METHODS

A total of 213 primary tumors were immunohistochemically stained for PD-L1 and scored for tumor (percentage), stroma (binary) and PD-L1 positive tumor infiltrating macrophages. Additionally, PD-L1 positive tumors were scored for expression pattern, that is diffuse or predominantly present at the tumor-stroma margin.

RESULTS

Staining was successful in 200 tumors, of which 75% were high risk HPV negative. Median followup was 62 months. Of 200 tumors 96 (48%) were PD-L1 positive (scored 1% or greater), of which 59 (62%) had a marginal expression pattern and 79 (82%) were high risk HPV negative (p = 0.03). Compared to PD-L1 negative tumors, the PD-L1 expression patterns had different prognostic values in the whole cohort as well as in the high risk HPV negative subgroup. On multivariable analyses a marginal expression pattern was associated with absent lymph node metastases (OR 0.4) while diffuse expression was associated with poor survival (HR 2.58). These results were more prominent in the high risk HPV negative subgroup (OR 0.25, HR 3.92).

CONCLUSIONS

PD-L1 was expressed in 48% of penile carcinomas and mainly in high risk HPV negative tumors. The pattern of expression was a prognostic factor as marginal expression was associated with absent lymph node metastases and diffuse expression was associated with poor survival.

Clinical relevance and implications of HPV-induced neoplasia in different anatomical locations

Human papillomaviruses (HPV) are widespread DNA viruses that can infect epithelial cells of the skin and mucosa. Most HPV infections remain clinically unapparent and clear spontaneously. In few cases, however, HPV infections persist and can cause benign and malignant neoplasms at different anatomic locations. Malignant HPV-induced neoplasms are caused by distinct types of HPV (oncogenic or high-risk (HR) HPV types) and present in the anogenital (anus, penis, uterine cervix, vagina and vulva) and head and neck (particularly oropharynx) region. In the anogenital region defined precancerous stages precede invasive cancer. In the head and neck region there is clear evidence only for the invasive stage of HPV-induced neoplasia. In early infection stages the HPV oncogenes (E6/E7) are under tight control in the basal and parabasal cell layers. In more advanced precancerous stages increased expression of the HPV oncogenes E6 and E7 occurs (transforming infection) that may result in transformation of these cells. The defined carcinogenesis in the anogenital tract enables cancer early detection, particularly at the uterine cervix where cytologic and molecular tests contribute to early diagnosis and treatment at a non-invasive stage. Up to now, the treatment of HPV-related precancerous stages (high-grade intraepithelial neoplasia) and cancer is not specifically targeting molecular characteristics of the virus. This article reviews the current state and new developments in epidemiology, prevention, diagnosis and treatment of HPV-associated neoplasia in various anatomic locations.

Genomic Profiling of Penile Squamous Cell Carcinoma Reveals New Opportunities for Targeted Therapy

Penile squamous cell carcinoma (PeSCCA) is a rare malignancy for which there are limited treatment options due to a poor understanding of the molecular alterations underlying disease development and progression. Therefore, we performed comprehensive, targeted next-generation sequencing to identify relevant somatic genomic alterations in a retrospective cohort of 60 fixed tumor samples from 43 PeSCCA cases (including 14 matched primary/metastasis pairs). We identified a median of two relevant somatic mutations and one high-level copy-number alteration per sample (range, 0-5 and 0-6, respectively). Expression of HPV and p16 was detectable in 12% and 28% of patients, respectively. Furthermore, advanced clinical stage, lack of p16 expression, and MYC and CCND1 amplifications were significantly associated with shorter time to progression or PeSCCA-specific survival. Notably, four cases harbored EGFR amplifications and one demonstrated CDK4 amplification, genes for which approved and investigational targeted therapies are available. Importantly, although paired primary tumors and lymph node metastases were largely homogeneous for relevant somatic mutations, we identified heterogeneous EGFR amplification in primary tumor/lymph node metastases in 4 of 14 cases, despite uniform EGFR protein overexpression. Likewise, activating HRAS mutations occurred in 8 of 43 cases. Taken together, we provide the first comprehensive molecular PeSCCA analysis, which offers new insight into potential precision medicine approaches for this disease, including strategies targeting EGFR.

Clinical Significance of p53 and p16(ink4a) Status in a Contemporary North American Penile Carcinoma Cohort

BACKGROUND

Because of the low incidence of penile carcinoma (PC), the value of p16(ink4a), p53, and human papilloma virus (HPV) infection status in clinical practice remains unclear. Herein, we report our experience with potential clinical utility of these markers in men with PC treated at our institution.

PATIENTS AND METHODS

Tissue microarrays of 57 cases of invasive penile squamous cell carcinomas were immunohistochemically stained for p16 and p53. HPV in situ hybridization (ISH) for high-risk subtypes was also performed. Association between marker status, nodal disease, overall (OS) and cancer-specific survival (CSS) were assessed.

RESULTS

p16 and HPV ISH were positive in 23 (40%) and 24 (42%) of the cohort, respectively. The proportion of warty, basaloid, or mixed warty basaloid tumor subtypes were significantly greater in the p16-positive patients (48% vs. 3%; P < .01). p53 expression was negative in 31 (54%) cases. Only in p16-negative patients, positive p53 status was associated with pN+ disease (odds ratio, 4.4 [95% confidence interval (CI), 1.04-18.6]). In Kaplan-Meier analysis, the unadjusted estimated OS was insignificantly longer in p16-positive patients (median OS, 75 vs. 27 months; P = .27) and median CSS was not reached (P = .16). In a multivariable Cox proportional hazard model, when controlling for pathological nodal status and adjuvant chemotherapy, p16 status was a significant predictor for improved CSS (hazard ratio, 0.36 [95% CI, 0.13-0.99]). The worst CSS was seen in pN+ patients with double negative p16 and p53 expression (8 vs. 34 months; P = .01).

CONCLUSION

In this current cohort, p53 and p16 status showed clinical utility in predicting nodal disease as well as survival.

Genital Human Papillomavirus Infection Progression to External Genital Lesions: The HIM Study

BACKGROUND

Human papillomavirus (HPV) causes two types of external genital lesions (EGLs) in men: genital warts (condyloma) and penile intraepithelial neoplasia (PeIN).

OBJECTIVE

The purpose of this study was to describe genital HPV progression to a histopathologically confirmed HPV-related EGL.

DESIGN, SETTING, AND PARTICIPANTS

A prospective analysis nested within the HPV Infection in Men (HIM) study was conducted among 3033 men. At each visit, visually distinct EGLs were biopsied; the biopsy specimens were subjected to pathologic evaluation and categorized by pathologic diagnoses. Genital swabs and biopsies were used to identify HPV types using the Linear Array genotyping method for swabs and INNO-LiPA for biopsy specimens.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

EGL incidence was determined among 1788 HPV-positive men, and cumulative incidence rates at 6, 12, and 24 mo were estimated. The proportion of HPV infections that progressed to EGL was also calculated, along with median time to EGL development.

RESULTS AND LIMITATIONS

Among 1788 HPV-positive men, 92 developed an incident EGL during follow-up (9 PeIN and 86 condyloma). During the first 12 mo of follow-up, 16% of men with a genital HPV 6 infection developed an HPV 6-positive condyloma, and 22% of genital HPV 11 infections progressed to an HPV 11-positive condyloma. During the first 12 mo of follow-up, 0.5% of men with a genital HPV 16 infection developed an HPV 16-positive PeIN. Although we expected PeIN to be a rare event, the sample size for PeIN (n=10) limited the types of analyses that could be performed.

CONCLUSIONS

Most EGLs develop following infection with HPV 6, 11, or 16, all of which could be prevented with the 4-valent HPV vaccine.

PATIENT SUMMARY

In this study, we looked at genital human papillomavirus (HPV) infections that can cause lesions in men. The HPV that we detected within the lesions could be prevented by a vaccine.

Classic and nonclassic HLA class I expression in penile cancer and relation to HPV status and clinical outcome

PURPOSE

Loss of expression of HLA class I is a mechanism of immune evasion in various cancers that is often associated with a worse patient outcome. We analyzed HLA expression in a large cohort with penile cancer in relation to clinical outcome.

MATERIALS AND METHODS

We used penile cancer tissue blocks from 168 patients who underwent surgical resection between 2000 and 2009 to construct tissue microarrays. Immunohistochemical staining was done with antibodies directed against classic and nonclassic HLA molecules. HLA expression was scored semiquantitatively, divided into 3 expression groups and correlated with clinicopathological variables, including HPV and survival. Survival analysis was performed using the Kaplan-Meier method and Cox proportional hazards models.

RESULTS

Complete and partial loss of total classic HLA class I was observed in 32% and 50% of cases, and up-regulation of HLA-E and G in 16% and 13%, respectively. When corrected for relevant clinical parameters, partial HLA-A loss was significantly associated with decreased survival overall (HR 2.3, 95% CI 1.1-4.6) and in HPV negative patients alone (HR 3.4, 95% CI 1.4-8.4). Abnormal HLA-B/C, E or G expression levels were not associated with survival.

CONCLUSIONS

To our knowledge this is the first study to describe a link between HLA expression and the clinical outcome of penile cancer. HLA down-regulation occurs frequently and partial loss of HLA-A is an independent predictor of poor survival in HPV negative patients. Complete understanding of the mechanisms and relevance of HLA down-regulation and immune evasion in regard to the clinical outcome will contribute to the future design of immunotherapy interventions.