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

The Prognostic Value of Human Papillomavirus Status in Penile Cancer: Outcomes From a Norwegian Cohort Study

INTRODUCTION

Penile squamous cell carcinoma (PSCC) can develop from human papillomavirus (HPV) infection. This study investigates if the prognostic value of the TNM stage groups or the components tumor stage (pT), grade of differentiation (Grade), lymphovascular invasion (LVI), and nodular stage (pN) depend on HPV status. Also, whether the value of tumor parameters (pT, Grade, and LVI) for predicting node-positive disease depends on HPV status was investigated.

PATIENTS AND METHODS

Stored tumor tissue from 226 patients treated for PSCC in Western Norway between 1973 and 2023 was investigated for HPV DNA. Histopathological variables were reevaluated according to the current TNM classification. Disease course was registered from hospital records. Inclusion of an interaction term between HPV and TNM stage groups in Cox regression enabled analysis of whether cancer-specific survival (CSS) of the stage groups depended on HPV status. This was also done separately for pT, Grade, LVI, and pN. Logistic regression with interaction terms between HPV and the tumor parameters were used to investigate if their predictive value depended on HPV status.

RESULTS

HPV DNA was detected in 43% of the tumors. Stratified by HPV status, there was no significant interaction term in the Cox regression between HPV status and TNM stage groups (P = .74). Similar results were found for pT (P = .94), Grade (P = .08), LVI (P = .91) and pN (P = .77). Moreover, there were no significant interaction terms in the logistic regression between HPV status and the tumor parameters pT, Grade, and LVI (all P > .2).

CONCLUSIONS

This study found that prognosis of the TNM stage groups and the components pT, Grade, LVI, and pN were not modified by HPV in PSCC. The value of pT, Grade, and LVI for predicting lymph node-positive disease was not affected by HPV status.

The impact of the tumor microenvironment on the survival of penile cancer patients

PeCa is a rare entity with rising incidence rates due to increased infections with human papillomaviruses (HPV). The distinct subtypes of PeCa with an individual pathogenesis demand biomarkers for a precise patient risk assessment regarding disease progression and therapeutic susceptibility. We recently identified promising candidates associated with an HPV-instructed tumor microenvironment (TME) using HPV-positive PeCa cell lines and tissue microarrays (TMA). The capacity of HPV + p63 + PeCa cells to release neutrophil-attracting CXCL-8 provided a molecular link explaining the infiltration of CD15 + myeloid cells in PeCa specimens. The candidate biomarkers HPV, p63, CD15, DKK1, and CD147 linked a tumor-promoting TME with a higher TNM classification reflecting more aggressive and metastasizing cancers. Based on immune-reactive scores (IRS) from TMA staining for these biomarkers, we calculated correlations and conducted association analyses to assess the degree of relationship between all biomarkers. We then conducted Kaplan-Meier survival estimates and Cox regression analyses to delineate the impact on PeCa patient survival. There is a notable predictive potential regarding the survival of patients with biomarker profiles beyond the potency of the individual biomarker. From all candidate biomarkers and biomarker profiles, the combination of CD147 and infiltrating CD15 + cells linked to an active HPV-driven transformation displayed cancer-immune dynamics with dismal prognosis for patients. After deciphering relevant interdependencies, the HPV + CD147 + CD15 + status was the most potent profile predicting metastasis-free survival of PeCa patients. The results of this report underscore the need for analysis of the TME and the development of multi-parameter composite scores that reflect fundamental cancer-immune relationships to tailor therapeutic interventions based on actual cancer immune dynamics.

HPV and Penile Cancer: Epidemiology, Risk Factors, and Clinical Insights

Penile cancer (PC) is a rare malignancy predominantly of squamous cell origin. Approximately 40% of penile tumors are associated with human papillomavirus (HPV) infection. Diagnosing PC remains challenging due to its rarity and variety of clinical presentations. Furthermore, the impact of HPV on the tumor immune microenvironment complicates clinical management, although recent advancements in immune checkpoint inhibitors (ICIs) have shown some efficacy in treating HPV-associated PC. Ongoing research efforts aim to develop oncologic treatments that target HPV-induced cellular modifications. Additionally, novel therapeutic vaccines and adoptive T-cell therapies targeting HPV oncoproteins represent emerging treatment modalities. Our review highlights the complex interplay between HPV and penile carcinogenesis, emphasizing its epidemiology, etiology, clinicopathological characteristics, and potential therapeutic implications.

Single-cell Atlas of Penile Cancer Reveals TP53 Mutations as a Driver of an Aggressive Phenotype, Irrespective of Human Papillomavirus Status, and Provides Clues for Treatment Personalization

BACKGROUND AND OBJECTIVE

TP53 loss-of-function (TP53LOF) mutations might be a driver of poor prognosis and chemoresistance in both human papillomavirus (HPV)-independent (HPV-) and HPV-associated (HPV+) penile squamous cell carcinoma (PSCC). Here, we aim to describe transcriptomic differences in the PSCC microenvironment stratified by TP53LOF and HPV status.

METHODS

We used single-cell RNA sequencing (scRNA-seq) and T-cell receptor sequencing to obtain a comprehensive atlas of the cellular architecture of PSCC. TP53LOF and HPV status were determined by targeted next-generation sequencing and sequencing HPV-DNA reads. Six HPV+ TP53 wild type (WT), six HPV- TP53WT, and four TP53LOF PSCC samples and six controls were included. Immunohistochemistry and hematoxylin-eosin confirmed the morphological context of the observed signatures. Prognostic differences between patient groups were validated in 541 PSCC patients using Kaplan-Meier survival estimates.

KEY FINDINGS AND LIMITATIONS

Patients with aberrant p53 staining fare much worse than patients with either HPV- or HPV+ tumors and WT p53 expression. Using scRNA-seq, we revealed 65 cell subtypes within 83 682 cells. TP53LOF tumors exhibit a partial epithelial-to-mesenchymal transition, immune-excluded, angiogenic, and morphologically invasive environment, underlying their aggressive phenotype. HPV- TP53WT tumors show stemness and immune exhaustion. HPV+ TP53WT tumors mirror normal epithelial maturation with upregulation of antibody-drug-conjugate targets and activation of innate immunity. Inherent to the scRNA-seq analysis, low sample size is a limitation and validation of signatures in large PSCC cohorts is needed.

CONCLUSIONS AND CLINICAL IMPLICATIONS

This first scRNA-seq atlas offers unprecedented in-depth insights into PSCC biology underlying prognostic differences based on TP53 and HPV status. Our findings provide clues for testing novel biomarker-driven therapies in PSCC.

PATIENT SUMMARY

Here, we analyzed tissues of penile cancer at the level of individual cells, which helps us understand why patients who harbor a deactivating mutation in the TP53 gene do much worse than patients lacking such a mutation. Such an analysis may help us tailor future therapies based on TP53 gene mutations and human papillomavirus status of these tumors.

High-risk human papilloma virus status & outcomes for penile squamous cell carcinoma: A single institution experience

OBJECTIVES

There is a paucity of data on North American cohorts of patients with penile squamous cell carcinoma (pSCC). Herein, we aimed to assess the sensitivity of various modalities to identify human papillomavirus (HPV) status, determine the prevalence of high-risk HPV-positivity, and evaluate the prognostic impact of relevant clinicopathologic variables.

METHODS

Patients with pSCC (n = 121) consecutively treated with partial/total penectomy (2000-2022) at a single institution were included. HPV status (based on immunohistochemistry [IHC], in situ hybridization [ISH], and panviral metagenomic sequencing [PMS]), histologic features, and outcomes were reviewed. Outcome events included death due to disease and progression.

RESULTS

The majority of patients were white (105/121, 86.8%). Thirty-seven (30.6%) were high-risk HPV-positive, and morphologic evaluation had a sensitivity of 97.3% (95% confidence interval [CI], 86.2-99.5) for predicting high-risk HPV status compared to IHC/ISH/PMS. Disease progression was more common among high-risk HPV-negative compared to high-risk HPV-positive patients (HR 2.74, CI 1.12-8.23, P = 0.03). Moreover, among high-risk HPV-negative patients, those with moderate-poorly differentiated tumors had increased disease-specific mortality (32.6%, CI 17.1-48.1) compared to those with well-differentiated tumors (0%). Among high-risk HPV-positive patients, those with basaloid morphology had lower disease-specific mortality (0% vs 14.4%, CI 0.0-33.1).

CONCLUSIONS

We demonstrate high-risk HPV-positivity in approximately one-third of patients with pSCC. Morphologic evaluation alone had a high sensitivity in correctly determining HPV status. Our results suggest that high-risk HPV status and morphologic features (differentiation in high-risk HPV-negative, and basaloid subtype in high-risk HPV-positive pSCC) may have prognostic value.

Human papillomavirus infection affects treatment outcomes and the immune microenvironment in patients with advanced penile squamous cell carcinoma receiving programmed cell death protein 1 inhibitor-based combination therapy

BACKGROUND

Penile squamous cell carcinoma (PSCC) is a human papillomavirus (HPV)-associated malignancy. Immunotherapy is emerging as a potential treatment for advanced PSCC. In this study, the authors analyzed the association of HPV status with outcomes and the immune microenvironment in patients with advanced PSCC undergoing programmed cell death protein 1 (PD1) inhibitor-based combination therapy (PCT).

METHODS

HPV status was assessed using quantitative polymerase chain reaction in 87 patients with advanced PSCC treated with PCT. Objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS) in the HPV+ and HPV- groups were compared. Additionally, bulk RNA sequencing was performed to investigate the potential impact of HPV on the immune microenvironment in advanced PSCC.

RESULTS

Among patients receiving first-line PCT, ORR (91.7% vs. 64.6%, p = .014) and DCR (100.0% vs. 79.2%, p = .025) in the HPV+ group were higher compared to the HPV- group. Kaplan-Meier curves demonstrated that the HPV+ group exhibited superior PFS (p = .005) and OS (p = .004) for patients in the first-line setting. However, these advantages of HPV infection were not observed in multi-line PCT (p > .050). HPV status remained an independent prognostic factor for predicting better ORR (p = .024), PFS (p = .002), and OS (p = .020) in the multivariate analyses. Landmark analyses showed that the HPV-induced superiority of PFS occurred at an early stage (within 3 months) and OS occurred at a relatively late stage (within 9 months). Bioinformatic analyses identified potential immune-activated genes (GLDC, CYP4F12, etc.) and pathways (RAGE, PI3K/AKT, etc.), antitumor immune cell subtypes, and lower tumor immune dysfunction and exclusion scores in HPV+ tissues.

CONCLUSIONS

HPV infection may confer treatment efficacy and survival benefits in patients with advanced PSCC receiving first-line PCT because of the possible stimulation of the antitumor immune microenvironment.

PLAIN LANGUAGE SUMMARY

Human papillomavirus (HPV) infection may induce better objective response rate, progression-free survival (PFS), and overall survival (OS) for advanced penile squamous cell carcinoma (PSCC) patients receiving first-line programmed cell death protein 1 inhibitor-based combination therapy (PCT) instead of multi-line PCT. HPV infection-induced PFS advantage occurs at an early stage (within 3 months) whereas OS superiority occurs at a relatively late stage (within 9 months). Antitumor immune microenvironment could be stimulated by HPV infection in advanced PSCC tissues.

Unveiling the Role of Human Papillomavirus in Urogenital Carcinogenesis a Comprehensive Review

Human papillomavirus (HPV), an oncogenic DNA virus, is the most common sexually transmitted virus and significant public health concern globally. Despite the substantial prevalence of HPV infection among men, routine testing remains elusive due to the lack of approved HPV tests and the complexity of detection methods. Various studies have explored the link between HPV and genitourinary cancers, revealing different associations influenced by geographic variation, histological subtype and methodological differences. These findings underscore the importance of further research to elucidate the role of HPV in male urogenital cancers. This comprehensive review delves into the intricate relationship between HPV and male genitourinary cancers, shedding light on the virus's oncogenic mechanisms and its reported prevalence. A deeper understanding of HPV's implications for male health is essential for advancing public health initiatives and reducing the burden of urogenital cancers worldwide.

Research Progress of PD 1/PD L1 Inhibitors in the Treatment of Urological Tumors

Immune checkpoint inhibitors (ICIs) offer significant advantages for the treatment of urologic tumors, enhancing the immune function of anti-tumor T cells by inhibiting PD-1 and PDL1 binding. They have been shown to be well tolerated and remarkably effective in clinical practice, offering hope to many patients who are not well treated with conventional drugs. Clinical trials in recent years have shown that anti-PD-1 and PD-L1 antibodies have good efficacy and safety in the treatment of urologic tumors. These antibodies can be applied to a variety of urologic tumors, such as bladder cancer, renal cell carcinoma, and prostate cancer. They have been approved for the first-line treatment or as an option for follow-up therapy. By blocking the PD-1/PD-L1 signaling pathway, ICIs can release immune functions that are suppressed by tumor cells and enhance T-cell killing, thereby inhibiting tumor growth and metastasis. This therapeutic approach has achieved encouraging efficacy and improved survival for many patients. Although ICIs have shown remarkable results in the treatment of urologic tumors, some problems remain, such as drug resistance and adverse effects in some patients. Therefore, further studies remain important to optimize treatment strategies and improve clinical response in patients. In conclusion, PD-1/PD-L1 signaling pathway blockers have important research advances for the treatment of urologic tumors. Their emergence brings new hope for patients who have poor outcomes with traditional drug therapy and provides new options for immunotherapy of urologic tumors. The purpose of this article is to review the research progress of PD-1 and PD-L1 signaling pathway blockers in urologic tumors in recent years.

Safety and efficacy of immune checkpoint inhibitors in advanced penile cancer: report from the Global Society of Rare Genitourinary Tumors

BACKGROUND

Treatment options for penile squamous cell carcinoma are limited. We sought to investigate clinical outcomes and safety profiles of patients with penile squamous cell carcinoma receiving immune checkpoint inhibitors.

METHODS

This retrospective study included patients with locally advanced or metastatic penile squamous cell carcinoma receiving immune checkpoint inhibitors between 2015 and 2022 across 24 centers in the United States, Europe, and Asia. Overall survival and progression-free survival were estimated using the Kaplan-Meier method. Objective response rates were determined per Response Evaluation Criteria in Solid Tumours 1.1 criteria. Treatment-related adverse events were graded per the Common Terminology Criteria for Adverse Events, version 5.0. Two-sided statistical tests were used for comparisons.

RESULTS

Among 92 patients, 8 (8.7%) were Asian, 6 (6.5%) were Black, and 24 (29%) were Hispanic and/or Latinx. Median (interquartile range) age was 62 (53-70) years. In all, 83 (90%) had metastatic penile squamous cell carcinoma, and 74 (80%) had received at least second-line treatment. Most patients received pembrolizumab monotherapy (n = 26 [28%]), combination nivolumab-ipilimumab with or without multitargeted tyrosine kinase inhibitors (n = 23 [25%]), or nivolumab (n = 16 [17%]) or cemiplimab (n = 15 [16%]) monotherapies. Median overall and progression-free survival were 9.8 months (95% confidence interval = 7.7 to 12.8 months) and 3.2 months (95% confidence interval = 2.5 to 4.2 months), respectively. The objective response rate was 13% (n = 11/85) in the overall cohort and 35% (n = 7/20) in patients with lymph node-only metastases. Visceral metastases, Eastern Cooperative Oncology Group (ECOG) performance status of 1 or higher, and a higher neutrophil/lymphocyte ratio were associated with worse overall survival. Treatment-related adverse events occurred in 27 (29%) patients, and 9.8% (n = 9) of the events were grade 3 or higher.

CONCLUSIONS

Immune checkpoint inhibitors are active in a subset of patients with penile squamous cell carcinoma. Future translational studies are warranted to identify patients more likely to derive clinical benefit from immune checkpoint inhibitors.

Evaluation of Prognostic Parameters to Identify Aggressive Penile Carcinomas

BACKGROUND

Advanced penile carcinoma is characterized by poor prognosis. Most data on prognostic factors are based on small study cohorts, and even meta-analyses are limited in patient numbers. Therefore, there is still a lack of evidence for clinical decisions. In addition, the most recent TNM classification is questionable; in line with previous studies, we found that it has not improved prognosis estimation.

METHODS

We evaluated 297 patients from Germany, Russia, and Portugal. Tissue samples from 233 patients were re-analyzed by two experienced pathologists. HPV status, p16, and histopathological parameters were evaluated for all patients.

RESULTS

Advanced lymph node metastases (N2, N3) were highly significantly associated with reductions in metastasis-free (MFS), cancer-specific (CS), and overall survival (OS) rates (p = <0.001), while lymphovascular invasion was a significant parameter for reduced CS and OS (p = 0.005; p = 0.007). Concerning the primary tumor stage, a significant difference in MFS was found only between pT1b and pT1a (p = 0.017), whereas CS and OS did not significantly differ between T categories. In patients without lymph node metastasis at the time of primary diagnosis, lymphovascular invasion was a significant prognostic parameter for lower MFS (p = 0.032). Histological subtypes differed in prognosis, with the worst outcome in basaloid carcinomas, but without statistical significance. HPV status was not associated with prognosis, either in the total cohort or in the usual type alone.

CONCLUSION

Lymphatic involvement has the highest impact on prognosis in penile cancer, whereas HPV status alone is not suitable as a prognostic parameter. The pT1b stage, which includes grading, as well as lymphovascular and perineural invasion in the T stage, seems questionable; a revision of the TNM classification is therefore required.

[Importance of HPV status and p16 for the prognosis of penile carcinoma]

BACKGROUND

Penile cancer is a rare but often lethal tumour disease, especially in the metastatic stage. Most data on prognostic factors for penile cancer are based on small patient cohorts, and even meta-analyses are mostly limited in terms of patient numbers. There is a lack of sufficient parameters to predict the metastatic risk of these tumours. Furthermore, the role of the HPV status for the prognosis, and, in this regard, of p16INK4a is still unclear.

MATERIAL AND METHODS

In this study, 236 patients from an international multicentre cohort were analysed with regard to histological subtypes, HPV and p16 status, and other clinical parameters. The HPV status was only graded as HPV-positive if HPV was detected by PCR and the p16 status defined by immunochemistry was positive. The statistical analysis was carried out using the Kaplan-Meier method as well as the log-rank test and a univariable and multivariable analysis using the Cox regression model.

RESULTS

A positive HPV status was not a significant parameter for either metastasis-free (MFS), tumour-specific (CSS) or overall survival (OS). p16-positive tumours showed a significantly better MFS (p=0.026), which was also confirmed in the subgroup analysis of HPV-negative tumours (p=0.037) without differences in CSS or OS. In the usual type, there was also a trend towards an improved MFS, but without statistical significance (p=0.070). p16-positive tumours were associated with a highly significantly better MFS (hazard ratio 0.3; p=0.004) in the multivariable Cox regression, while patients with a pT1b tumour stage or advanced lymph node metastasis showed a significantly worse survival. In the multivariable analysis of HPV-negative tumours, p16 status was also confirmed as an independent predictor of MFS (Hazard ratio 0.2; p=0.007).

CONCLUSION

HPV status alone seems to be lacking prognostic relevance. In contrast, p16 status was confirmed as an independent prognostic factor. Thus, the expression of p16INK4a is associated with a significantly better MFS. Especially in HPV-negative tumours, the p16 status should be evaluated with regard to the prognostic value and thus also with a view to the treatment decision.

The Prognostic Role of Human Papillomavirus and p16 Status in Penile Squamous Cell Carcinoma-A Systematic Review

PSCC is a rare cancer, with approximately half of all cases related to HPV. While HPV and p16 IHC testing have proven their prognostic value for oropharyngeal cancer, this is not yet established for PSCC. The current level of evidence exploring the relation between PSCC and HPV is moderate, so we conducted a systematic review following PRISMA guidelines to evaluate the prognostic role of HPV and p16 IHC in PSCC clinical outcomes. We searched the PubMed, Embase, and Cochrane databases and identified 34 relevant studies that met our inclusion criteria. Of these, 33 were retrospective cohort studies, and one was a cross-sectional study. Nine studies reported that HPV-positive and p16-positive PSCC had better overall survival (OS) and disease-free survival (DFS). This study highlights the need for a meta-analysis to determine the role of routine HPV status or p16 staining testing as part of the initial diagnosis and staging of PSCC patients worldwide.

A cross-sectional study of human papillomavirus genotype distribution and integration status in penile cancer among Chinese population

Human papillomavirus (HPV) has been recognized as an important risk factor in penile cancer. This study aimed to investigate the HPV subtypes and integration status in Chinese patients. Samples were collected from 103 penile cancer patients aged 24-90 years between 2013 and 2019. We found that HPV infection rate was 72.8%, with 28.0% integration. The aging patients were more susceptible to HPV (p = 0.009). HPV16 was the most frequent subtype observed (52/75) and exhibited the highest frequency of integration events, with 11 out of 30 single infection cases showing integration positive. The HPV integrations sites in the viral genome were not randomly distributed, the breakpoints were enriched in the E1 gene (p = 0.006) but relatively scarce in L1, E6 and E7. Our research might provide some clues how HPV leads to the progression of penile cancer.

Human papillomavirus in men

OBJECTIVE

To describe the clinical behavior of human papillomavirus in men.

MATERIALS AND METHODS

Current international literature was reviewed to describe the clinical behavior of human papillomavirus in men.

RESULTS

Internationally, the overall prevalence of HPV DNA is 50.8%, HPV considered high risk are 14 types. Prevalence of HPV DNA in invasive penile cancer ranges from 33.1% to 47%. HPV-16 has been the most frequent (68.3%), followed by HPV-6 (8.1%) and HPV-18 (6.9%). Positive HPV is described as an independent prognostic factor for cancer-specific survival.

CONCLUSION

It is not clear why HPV infection has a predilection in specific areas of the genital tract. However, it is important to note that there are factors that increase the risk of HPV infection.

Prognostic Significance of p16 and Its Relationship with Human Papillomavirus Status in Patients with Penile Squamous Cell Carcinoma: Results of 5 Years Follow-Up

Penile Squamous Cell Carcinoma (PSCC) is associated with high-risk human papillomavirus (HR-HPV). The immunohistochemical (IHC) test for p16^INK4a (p16) is highly correlated with HR-HPV expression in other SCCs. To investigate whether the expression of p16 IHC or HR-HPV is associated with survival in PSCC, we conducted a single institution analysis of 143 patients with a diagnosis of PSCC and, available tissue were tested for p16 IHC staining patterns, histological subtype, tumor grade, and lymphovascular invasion (LVI) by an experienced pathologist. HR-HPV status using the Cobas PCR Assay or the RNAScope high-risk HPV in situ hybridization kit were also assessed. Patient characteristics were summarized using descriptive statistics of clinico-pathologic variables. Kaplan-Meier was used to estimate median overall survival (OS), cancer specific survival (CSS) and correlated with HPV, p16, and other study variables. Patients with p16+ tumors had a significantly longer median CSS in comparison to the p16- group (p = 0.004), with respective 5-year CSS probability of 88% (95% CI; 0.84, 1) versus 58% (95% CI; 0.55, 0.76; p = 0.004). HPV status did not predict survival outcomes. Multivariable analysis with respect to OS and CSS, showed that p16+ status was associated with a lower risk of death (HR = 0.36, 95%CI; 0.20-0.67, p = 0.001), and improved CSS (HR = 0.20, 95% CI; 0.07-0.54, p = 0.002) after adjusting for covariates. In conclusion, tumor p16 status via IHC was an easy to perform independent prognostic factor for OS and CSS that correlates with HR-HPV expression.

Immune landscape and immunotherapy for penile cancer

Penile cancer is a rare malignancy and usually refers to penile squamous cell carcinoma (PSCC), which accounts for more than 95% of all penile malignancies. Although organ-sparing surgery is an effective treatment for early-stage PSCC, surgical intervention alone is often not curative for advanced PSCC with metastases to the inguinal and/or pelvic lymph nodes; thus, systemic therapy is required (usually platinum-based chemotherapy and surgery combined). However, chemotherapy for PSCC has proven to be of limited efficacy and is often accompanied by high toxicity, and patients with advanced PSCC usually have poor prognosis. The limited treatment options and poor prognosis indicate the unmet need for advanced PSCC. Immune-based therapies have been approved for a variety of genitourinary and squamous cell carcinomas but are rarely reported in PSCC. To date, several studies have reported high expression of PDL1 in PSCC, supporting the potential application of immune checkpoint inhibitors in PSCC. In addition, human papillomavirus (HPV) infection is highly prevalent in PSCC and plays a key role in the carcinogenesis of HPV-positive PSCC, suggesting that therapeutic HPV vaccine may also be a potential treatment modality. Moreover, adoptive T cell therapy (ATC) has also shown efficacy in treating advanced penile cancer in some early clinical trials. The development of new therapeutics relies on understanding the underlying biological mechanisms and processes of tumor initiation, progression and metastasis. Therefore, based on the interest, we reviewed the tumor immune microenvironment and the emerging immunotherapy for penile cancer.

Updates in the use of radiotherapy in the management of primary and locally-advanced penile cancer

Objective

Penile cancer is a rare malignancy in most developed countries, but may represent a significant oncologic challenge in certain African, Asian, and South American regions. Various treatment approaches have been described in penile cancer, including radiotherapy. This review aimed to provide a synopsis of radiotherapy use in penile cancer management and the associated toxicities. In addition, we aimed to discuss palliative radiation for metastases to the penis and provide a brief overview of how tumor biology may assist with treatment decision-making.

Methods

Peer-reviewed manuscripts related to the treatment of penile cancer with radiotherapy were evaluated by a PubMed search (1960–2021) in order to assess its role in the definitive and adjuvant settings. Selected manuscripts were also evaluated for descriptions of radiation-related toxicity.

Results

Though surgical resection of the primary is an excellent option for tumor control, select patients may be treated with organ-sparing radiotherapy by either external beam radiation or brachytherapy. Data from randomized controlled trials comparing radiotherapy and surgery are lacking, and thus management is frequently determined by institutional practice patterns and available expertise. Similarly, this lack of clinical trial data leads to divergence in opinion regarding lymph node management. This is further complicated in that many cited studies evaluating lymph node radiotherapy used non-modern radiotherapy delivery techniques. Groin toxicity from either surgery or radiotherapy remains a challenging problem and further risk assessment is needed to guide intensification with multi-modal therapy. Intrinsic differences in tumor biology, based on human papillomavirus infection, may help aid future prognostic and predictive models in patient risk stratification or treatment approach.

Conclusion

Penile cancer is a rare disease with limited clinical trial data driving the majority of treatment decisions. As a result, the goal of management is to effectively treat the disease while balancing the importance of quality of life through integrated multidisciplinary discussions. More international collaborations and interrogations of penile cancer biology are needed to better understand this disease and improve patient outcomes.

Clinical and Novel Biomarkers in Penile Carcinoma: A Prospective Review

Penile carcinoma is a rare urological neoplasia in men compared to other more common tumors, such as prostate, kidney, or bladder tumors. However, this neoplasm continues to affect a large number of patients worldwide, with developing countries presenting the highest incidence and mortality rates. Important risk factors such as the human papilloma virus, a factor affecting a large number of patients, have been described; however, few studies have evaluated screening programs in populations at risk for this disease, which severely affects the quality of life of older men. The management of these patients is usually complex, requiring surgical interventions that are not without risk and that have a great impact on the functionality of the male reproductive system. In addition, in cases of disseminated disease or with significant locoregional involvement, patients are evaluated by multidisciplinary oncological committees that can adjust the application of aggressive neoadjuvant or adjuvant chemotherapy on numerous occasions without clear improvement in survival. Chemotherapy regimens are usually aggressive, and unlike in other urological neoplasms, few advances have been made in the use of immunotherapy in these patients. The study of serological and histological biomarkers may help to better understand the underlying pathophysiology of these tumors and select patients who have a higher risk of metastatic progression. Similarly, the analysis of molecular markers will improve the availability of targeted therapies for the management of patients with disseminated disease that would benefit prognosis. Therefore, the purpose of this article is to summarize the main advances that have occurred in the development of serological and histological markers and their therapeutic implications in patients diagnosed with penile carcinoma, explaining the limitations that have been observed and analyzing future perspectives in the management of this disease.

Proteases and HPV-Induced Carcinogenesis

Simple Summary

Human papillomavirus (HPV) infection is a sexually transmitted disease with high prevalence worldwide. Although most HPV infections do not lead to cancer, some HPV types are correlated with the majority of cervical cancers, and with some anogenital and oropharyngeal cancers. Moreover, enzymes known as proteases play an essential role in the pathogenic process in HPV-induced carcinogenesis. This review highlights the role of proteases and recent epidemiological data regarding HPV-dependent carcinogenesis.

Abstract

Persistent infection with Human papillomavirus (HPV) is the main etiologic factor for pre-malignant and malignant cervical lesions. Moreover, HPV is also associated with oropharynx and other anogenital carcinomas. Cancer-causing HPV viruses classified as group 1 carcinogens include 12 HPV types, with HPV 16 and 18 being the most prevalent. High-risk HPVs express two oncoproteins, E6 and E7, the products of which are responsible for the inhibition of p53 and pRB proteins, respectively, in human keratinocytes and cellular immortalization. p53 and pRB are pleiotropic proteins that regulate the activity of several signaling pathways and gene expression. Among the important factors that are augmented in HPV-mediated carcinogenesis, proteases not only control processes involved in cellular carcinogenesis but also control the microenvironment. For instance, genetic polymorphisms of matrix metalloproteinase 1 (MMP-1) are associated with carcinoma invasiveness. Similarly, the serine protease inhibitors hepatocyte growth factor activator inhibitor-1 (HAI-1) and -2 (HAI-2) have been identified as prognostic markers for HPV-dependent cervical carcinomas. This review highlights the most crucial mechanisms involved in HPV-dependent carcinogenesis, and includes a section on the proteolytic cascades that are important for the progression of this disease and their impact on patient health, treatment, and survival.

Immunotherapeutic Approaches for the Treatment of HPV-Associated (Pre-)Cancer of the Cervix, Vulva and Penis

Human papillomavirus (HPV) infection drives tumorigenesis in almost all cervical cancers and a fraction of vulvar and penile cancers. Due to increasing incidence and low vaccination rates, many will still have to face HPV-related morbidity and mortality in the upcoming years. Current treatment options (i.e., surgery and/or chemoradiation) for urogenital (pre-)malignancies can have profound psychosocial and psychosexual effects on patients. Moreover, in the setting of advanced disease, responses to current therapies remain poor and nondurable, highlighting the unmet need for novel therapies that prevent recurrent disease and improve clinical outcome. Immunotherapy can be a useful addition to the current therapeutic strategies in various settings of disease, offering relatively fewer adverse effects and potential improvement in survival. This review discusses immune evasion mechanisms accompanying HPV infection and HPV-related tumorigenesis and summarizes current immunotherapeutic approaches for the treatment of HPV-related (pre-)malignant lesions of the uterine cervix, vulva, and penis.

p53 and p16ink4a As Predictive and Prognostic Biomarkers for Nodal metastasis and Survival in A Contemporary Cohort of Penile Squamous Cell Carcinoma

BACKGROUND

Human papilloma virus (HPV) infection is implicated in a proportion of invasive squamous cell carcinoma of the penis (PC). A subset of PC involves dysregulation of the p53 pathway. HPV in situ hybridization (ISH) and p16^ink4a positivity are surrogate markers for HPV infection, and p53 immunohistochemistry (IHC) denotes abnormality in the p53 pathway. There remains an ambiguity with regard to the contribution of both the pathways in the prognosis of PC. We sought to analyze the clinicopathologic characteristics of a cohort of Indian PC patients with respect to p16 ^ink4a and p53 expression.

PATIENTS AND METHODS

A cohort of 123 PC patients was studied for p16^ink4aand p53IHC and HPVISH. The results of these biomarkers were correlated with various clinicopathologic parameters.

RESULTS

p16^ink4a and HPV ISH were positive in 47% and 53% of the tumors, respectively. The proportion of warty, basaloid, or mixed warty-basaloid tumor subtypes showed significant p16^ink4apositivity (P < .0001) compared to other subtypes. Twenty-eight patients were dual negative (p53- /p16^ink4a-), 32 were dual positive (p53+/p16^ink4a+), 38 were p53+/p16^ink4a-, and 25 were p53-/p16^ink4a +. In patients where p16^ink4a was negative, a p53-positive phenotype had a higher propensity for lymph node metastases (OR, 5.42; 95% CI, 1.75-16.80; P = .003). Similarly, p53 positivity dictates nodal involvement in the p16^ink4a-positive subset of tumors (OR, 5.00; 95% CI, 1.23-20.17; P = .024). On multivariate analyses, pathologic subtypes (warty, warty-basaloid, and basaloid) (P < .0001), p16^ink4aexpression (P < .0001), and absence of nodal metastasis (P < .0001) were significant predictors of improved overall (OS) and cancer specific survival (CSS). In Kaplan-Meier analysis, the OS was significantly longer in patients with p16^ink4a + tumors (P < .0001), as was the CSS (P < .0001). Patients with dual positive tumors had a significantly higher OS (P < .001) and CSS (P = .012), in the entire cohort. In the node positive patients, dual positivity was associated with significantly higher OS (P < .0001); however, the median CSS for p53+/p16^ink4a+tumors were not significantly different compared to p53- /p16^ink4a- tumors (P = .064), although there was a trend towards improved CSS.

CONCLUSIONS

There is a strong concordance between p16^ink4aIHC and HPV ISH results. p16^ink4a status is an independent predictor of survival (OS and CSS) in our cohort of PCs. p53 is a predictor of nodal metastasis irrespective of p16 status. Dual positive tumors have a significantly better outcome in comparison to dual negative tumors.

Distinct Patterns of Myeloid Cell Infiltration in Patients With hrHPV-Positive and hrHPV-Negative Penile Squamous Cell Carcinoma: The Importance of Assessing Myeloid Cell Densities Within the Spatial Context of the Tumor

Comprehensive analysis of tumor infiltrating myeloid cells in the tumor microenvironment of penile squamous cell carcinoma (PSCC) is lacking. In this retrospective study, for the first time, PSCC resection specimens (N = 103) were annotated into the following compartments: intratumoral tumor (IT Tumor), intratumoral stroma (IT Stroma), peritumoral tumor (PT Tumor) and peritumoral stroma (PT Stroma) compartments. We then quantified CD14+, CD68+ and CD163+ myeloid cells within these compartments using an image analysis software and assessed their association with various clinical parameters, including high-risk human papillomavirus (hrHPV) status. In the total cohort, hrHPV status, grade of differentiation, age and tumor size were associated with myeloid cell densities. hrHPV⁺ tumors had higher infiltration rates of CD14+, CD68+ and CD163+ myeloid cells in the IT tumor compartment (p < 0.001, for all) compared to hrHPV^- tumors. Furthermore, when examining the association between compartment-specific infiltration and differentiation grade, increased myeloid cell densities in the IT tumor compartment were associated with a more advanced histological grade (p < 0.001, for all). This association remained significant when the hrHPV^- cohort (N = 60) was analyzed (CD14+ p = 0.001; CD68+ p < 0.001; CD163+ p = 0.004). Subgroup analysis in the hrHPV⁺ group (N = 43) showed that high infiltration rates of CD68+ and CD163+ cells in the PT tumor compartment were associated with lymph node (LN) metastasis (p = 0.031 and p = 0.026, respectively). Regarding the association between myeloid cell densities and disease-specific survival, the risk of death was found to decrease slightly as the number of myeloid cells in the IT tumor compartment increased (CD14+ p = 0.04; CD68+ p = 0.05; CD163+ p = 0.02). However, after adjusting for hrHPV, no independent association between myeloid densities and disease-specific survival were found. Altogether, these findings demonstrate the importance of assessing myeloid cell densities within the spatial context of the tumor. Further studies are needed to unravel the specific phenotype of myeloid cells residing in the different compartments, their effect on clinical parameters and the impact of hrHPV on the recruitment of myeloid cell populations in PSCC.

High-dose-rate brachytherapy with surface applicator in penile cancer

PURPOSE

An alternative to surgery for penile cancer is radiation therapy which is administered with external beam techniques and/or brachytherapy (BT) either interstitial or using a surface applicator. Here we report our experience in penile cancer patients treated with high-dose-rate (HDR)-BT with the surface technique, analyzing dosimetric parameters and clinical outcomes.

METHODS AND MATERIALS

Between June 2016 and December 2019, 7 patients with squamous cell carcinoma of the penis received HDR-BT by means of customized applicators that were constructed using a 3D printer or thermoplastic mask. The total dose was 57 Gy in 19 fractions.

RESULTS

Median clinical target volume percentage receiving 95%, 125%, and 150% of the prescribed dose were 93.1% (range 92.2-98.5), 12% (range 7.4-32.2), and 0.24% (range 0-10.8), respectively. Median urethral volumes receiving 90% and 115% of the prescribed dose were 40.2% (range 21.0-83.8) and 0% (range 0-1), respectively. All patients achieved complete remission. No patient developed G3 or G4 acute or late toxicities. No patient experienced urethral stenosis.

CONCLUSIONS

Surface HDR-BT in penile cancer is feasible and is associated with a high tolerance profile and good outcomes.

Prevalence of Human Papillomavirus (HPV) DNA among Men with Oropharyngeal and Anogenital Cancers: A Systematic Review and Meta-Analysis

OBJECTIVE

The term ''Human Papillomavirus'' or ''HPV'' has become synonymous with uterine cervical cancer leading to feminisation of all the preventive measures, especially immunisation. Taking into consideration the rising number of HPV associated cancers among men in many developed countries and the risk of transmission to women, male HPV infection is a serious concern. A systematic review and meta-analysis of literature was performed to determine the global prevalence of HPV among men with oropharyngeal and anogenital cancers.

METHODS

A systematic review and meta-analysis of literature was performed searching electronic databases for published articles in English between January 1984- April 2020 based on standard systematic review guidelines. The meta-analysis component was modified appropriately for the synthesis of prevalence study results. National Institutes of Health checklist for observational, cohort and cross-sectional studies was used to assess the quality of the studies selected after the abstract and content review. The meta-analysis was performed in STATA version 13.0 (College Station, Texas 77,845 USA) and the forest plots were constructed using metan package in STATA.

RESULTS

Through the electronic search of databases, 3486 original articles were screened for eligibility. Fifty-eight articles were systematically reviewed and 42 articles were qualified for meta-analysis including 4,250 men with oropharyngeal, penile and prostate cancers. The pooled prevalence of HPV DNA in oropharyngeal cancers was 45% (95%CI 24.0%-66.0%). Meanwhile the pooled prevalence rates of 48% (CI 40.0%- 57.0%) and 19% (CI 10.0%-29.0%) were observed in penile and prostate cancers respectively. Even though, articles regarding HPV prevalence in anal cancers were systematically reviewed, none of the studies were qualified for meta-analysis.

CONCLUSION

Higher pooled prevalence of HPV DNA was observed among men with oropharyngeal and penile cancers. Multicentric molecular studies investigating the prevalence of HPV in prostate cancers have to be planned in future.

The Biomarker Potential of Caveolin-1 in Penile Cancer

Various types of human cancers were characterized by an altered expression of epithelial or stromal caveolin-1 (CAV1). However, the clinical significance of CAV1 expression in penile cancer remains largely unknown. Here the expression patterns of CAV1 were analyzed in a retrospective cohort (n=43) of penile squamous cell carcinomas (SCC). Upon penile cancer progression, significantly increased CAV1-levels were determined within the malignant epithelium, whereas within the tumor stroma, namely the fibroblastic tumor compartment harboring activated and/or cancer associated fibroblasts, CAV1 levels significantly decline. Concerning the clinicopathological significance of CAV1 expression in penile cancer as well as respective epithelial-stromal CAV1 distributions, high expression within the tumor cells as well as low expression of CAV1 within the stromal compartment were correlated with decreased overall survival of penile cancer patients. Herein, CAV1 expressions and distributions at advanced penile cancer stages were independent of the immunohistochemically proven tumor protein p53 status. In contrast, less differentiated p16-positive tumor epithelia (indicative for human papilloma virus infection) were characterized by significantly decreased CAV1 levels. Conclusively, we provide further and new evidence that the characteristic shift in stromal‐epithelial CAV1 being functionally relevant to tumor progression even occurs in penile SCC.

miRNA Expression Characterizes Histological Subtypes and Metastasis in Penile Squamous Cell Carcinoma

Although microRNAs are described as promising biomarkers in many tumor types, little is known about their role in PSCC. Thus, we attempted to identify miRNAs involved in tumor development and metastasis in distinct histological subtypes considering the impact of HPV infection. In a first step, microarray analyses were performed on RNA from formalin-fixed, paraffin-embedded tumor (22), and normal (8) tissue samples. Microarray data were validated for selected miRNAs by qRT-PCR on an enlarged cohort, including 27 tumor and 18 normal tissues. We found 876 significantly differentially expressed miRNAs (p ≤ 0.01) between HPV-positive and HPV-negative tumor samples by microarray analysis. Although no significant differences were detected between normal and tumor tissue in the whole cohort, specific expression patterns occurred in distinct histological subtypes, such as HPV-negative usual PSCC (95 differentially expressed miRNAs, p ≤ 0.05) and HPV-positive basaloid/warty subtypes (247 differentially expressed miRNAs, p ≤ 0.05). Selected miRNAs were confirmed by qRT-PCR. Furthermore, microarray data revealed 118 miRNAs (p ≤ 0.01) that were significantly differentially expressed in metastatic versus non-metastatic usual PSCC. The lower expression levels for miR-137 and miR-328-3p in metastatic usual PSCC were validated by qRT-PCR. The results of this study confirmed that specific miRNAs could serve as potential diagnostic and prognostic markers in single PSCC subtypes and are associated with HPV-dependent pathways.

An overview of the diagnoses and treatments for penile cancer

Penile cancer is a rare malignancy and, as a consequence, it is managed in just a few specialist centres across the UK. This article aims to provide health professionals with an introduction and update on the epidemiology and aetiology of penile cancer, as well as the techniques used to diagnose penile cancer and the current treatment options. The article highlgihts the importance of early diagnosis and the role that the clinical nurse specialist in plays supporting those diagnosed with the penile cancer and their families.

The HPV and p63 Status in Penile Cancer Are Linked with the Infiltration and Therapeutic Availability of Neutrophils

Squamous penile cancer displays a rare human papillomavirus (HPV)-associated tumor entity. Investigations on the molecular pathogenesis of HPV-driven penile cancer are impaired by the rareness of clinical specimens and, in particular, are missing relevant cell culture models. Here, we identified in HPV-positive penile cancer cell lines that HPV16 oncoproteins control TP63 expression by modulating critical regulators, while integration into the TP63 open reading frame facilitates oncogene expression. The resulting feed-forward loop leads to elevated p63 levels that in turn enhance the release of the neutrophil-recruiting chemokine CXCL8. Remarkably, elevated CXCL8 amounts lead to the increased surface exposition of the Fc receptor of human IgA antibodies, FcαRI, on neutrophils and correlated with a higher susceptibility to antibody-dependent neutrophil-mediated cytotoxicity (ADCC) using an EGFR-specific IgA2 antibody. IHC staining of tissue microarrays proved that elevated expression of p63 together with neutrophil infiltration were significantly more frequent in HPV-positive penile cancer displaying a higher tumor grade. In summary, we identified a promising marker profile of patients with penile cancer at higher risk for worse prognosis. However, these patients may benefit from immunotherapeutic approaches efficiently engaging neutrophils for tumor cell killing.

Improving five-year survival prediction via multitask learning across HPV-related cancers

Oncology is a highly siloed field of research in which sub-disciplinary specialization has limited the amount of information shared between researchers of distinct cancer types. This can be attributed to legitimate differences in the physiology and carcinogenesis of cancers affecting distinct anatomical sites. However, underlying processes that are shared across seemingly disparate cancers probably affect prognosis. The objective of the current study is to investigate whether multitask learning improves 5-year survival cancer patient survival prediction by leveraging information across anatomically distinct HPV related cancers. Data were obtained from the Surveillance, Epidemiology, and End Results (SEER) program database. The study cohort consisted of 29,768 primary cancer cases diagnosed in the United States between 2004 and 2015. Ten different cancer diagnoses were selected, all with a known association with HPV risk. In the analysis, the cancer diagnoses were categorized into three distinct topography groups of varying specificity. The most specific topography grouping consisted of 10 original cancer diagnoses differentiated by the first two digits of the ICD-O-3 topography code. The second topography grouping consisted of cancer diagnoses categorized into six distinct organ groups. Finally, the third topography grouping consisted of just two groups, head-neck cancers and ano-genital cancers. The tasks were to predict 5-year survival for patients within the different topography groups using 14 predictive features which were selected among descriptive variables available in the SEER database. The information from the predictive features was shared between tasks in three different ways, resulting in three distinct predictive models: 1) Information was not shared between patients assigned to different tasks (single task learning); 2) Information was shared between all patients, regardless of task (pooled model); 3) Only relevant information was shared between patients grouped to different tasks (multitask learning). Prediction performance was evaluated with Brier scores. All three models were evaluated against one another on each of the three distinct topography-defined tasks. The results showed that multitask classifiers achieved relative improvement for the majority of the scenarios studied compared to single task learning and pooled baseline methods. In this study, we have demonstrated that sharing information among anatomically distinct cancer types can lead to improved predictive survival models.

Penile cancer: potential target for immunotherapy?

PURPOSE

Penile cancer (PeCa) is a rare malignancy with a poor prognosis in advanced disease. There is still a limited understanding of the biological mediators that are important in the prognosis and therapy of the disease. This review aims to provide a summary of the immune micro-environment, molecular oncogenesis and the role of HPV in the disease applying to the potential of the use of immunotherapy.

METHODS

Narrative, non-systematic review based on publications retrieved by PubMed and EMBASE search.

RESULTS

The molecular mechanisms underlying penile carcinogenesis are complex, and human papillomavirus (HPV) infection is a well-characterized driver of penile cancer. Up to 50% of the penile carcinomas are HPV related. There is potential to improve prevention, treatment and follow-up strategies pertaining to the role of HPV in penile cancer. Immune response modifiers such as toll-like receptor agonists are being used in a topical fashion for penile intraepithelial neoplasia while immune checkpoint inhibitors are currently under clinical investigation for its application in penile cancer.

CONCLUSIONS

The knowledge of prognosis-relevant biological pathways in penile cancer is expanding. HPV plays an important role in the carcinogenesis. This can lead to the identification of therapeutic targets which could significantly influence the prognosis of advanced penile cancer. Clinical trials are being conducted to pave the way for immune-modifying treatment modalities.

Equine Penile Squamous Cell Carcinomas as a Model for Human Disease: A Preliminary Investigation on Tumor Immune Microenvironment

Penile squamous cell carcinomas (SCCs) are common tumors in older horses, with poor prognosis mostly due to local invasion and recurrence. These tumors are thought to be mainly caused by Equus caballus papillomavirus type 2 (EcPV-2). The aim of this study is to characterize the tumor immune environment (TIME) in equine penile tumors. Equine penile epithelial tumors (17 epSCCs; 2 carcinomas in situ, CIS; 1 papilloma, P) were retrospectively selected; immune infiltrate was assessed by histology and immunohistochemistry; RT-qPCR tested the expression of selected chemokines and EcPV-2 DNA and RNA. The results confirmed EcPV-2-L1 DNA in 18/20 (90%) samples. L1 expression was instead retrieved in 13/20 cases (65%). The samples showed an increased infiltration of CD3⁺lymphocytes, macrophages (MAC387; IBA1), plasma cells (MUM1), and FoxP3⁺lymphocytes in the intra/peritumoral stroma when compared to extratumoral tissues (p < 0.05). Only MAC387⁺neutrophils were increased in EcPV-2^high viral load samples (p < 0.05). IL12/p35 was differentially expressed in EcPV^high and EcPV^low groups (p = 0.007). A significant decrease of IFNG and IL2 expression was highlighted in TGFB1-positive samples (p < 0.05). IBA1 and CD20 were intratumorally increased in cases where IL-10 was expressed (p < 0.005). EpSCCs may represent a good spontaneous model for the human counterpart. Further prospective studies are needed in order to confirm these preliminary results.

PD1/PD-L1 Axis in Uro-oncology

The immune system is important to control tumor development and progression in humans. However, tumor cells and cells of the tumor microenvironment can induce immune escape mechanisms including activation of immune checkpoints such as PD-1/PD-L1. Based on this knowledge, new immune therapies, including PD-1 and PD-L1 inhibition, have been developed and are already recommended as a standard treatment in metastatic bladder and kidney cancer patients. In addition to its role as a therapeutic target, PD-L1 seems to be a prognostic parameter although data are controversial. Only little is known about signaling pathways inducing PD-L1 expression in tumor cells on one hand and about its functional role for tumor cells itself. However, the understanding of the complex biological function of PD-L1 will improve therapeutic options in urological malignancies. This review is giving an overview of the current knowledge concerning the PD-1/PD-L1 axis in urological tumors including bladder, kidney, prostate, testicular and penile cancer.

Risk factors and molecular characterization of penile cancer: impact on prognosis and potential targets for systemic therapy

PURPOSE OF REVIEW

To provide a comprehensive summary of risk factors, molecular machinery as well as potential therapeutic targets with a particular focus on literature published in the last 2 years on prognosis and treatment of penile cancer (PeCa).

RECENT FINDINGS

E2F, LAMC2, MAML2, ID1 and IGFBP2 proteins were demonstrated to play a critical role for aggressive tumor behavior and might predict poor survival in PeCa. PD-L1 axis was confirmed as a promising pathway to serve as a therapeutic target. A number of genetic alterations were illuminated. In clinical testing, pan-HER tyrosine kinase inhibitor dacomitinib provided promising results in chemo-naïve and EGFR monoantibody nimotuzumab in chemotherapy-failed PeCa patients.

SUMMARY

Knowledge of prognosis-relevant altered molecular pathways in PeCa is expanding paving the way for identification of potential therapeutic targets. Multicenter clinical trials in the setting of centralized PeCa care are warranted to foster effective marker-based individualized treatment strategies.

Importance of HPV in Chinese Penile Cancer: A Contemporary Multicenter Study

Objective: To investigate the HPV DNA prevalence and genotype distribution among penile cancer in China. To identify association between HPV prevalence, different histological subtypes, tumor stage, tumor grade, demographics, comorbidity, and phimosis incidence trend. Standardized HPV DNA detection and p16^INK4a expression were used in a multi-center series of 340 penile squamous cell carcinomas diagnosed from 2006 to 2017.

Materials and Methods: HPV DNA detection and genotyping were examined by a validated kit for 23 different HPV subtypes (PCR-RDB HPV test). The cases with positive HPV DNA were additional tested for p16^INK4a expression to confirm the HPV infection.

Results: Using the PCR-RDB HPV test, overall HPV prevalence was 48.8% (166/340) and that of p16^INK4a expression was 45.6%. In this studied population, HPV16 was the most frequent HPV type detected in HPV-positive cancers (76.5%). HPV18 was the second most common type in penile cancers (15.1%). After pathology review, 307 cases were confirmed as invasive penile cancer, and the other 33 were non-invasive caners. The histologic subtypes of warty, basaloid, clear cell papillary, adenosquamaous and pseudohyperplastic were showed high HPV DNA prevalence. Among invasive cancers, no statistically significant differences in prevalence were observed by tumor grade, tumor stage or lymphnode stage at diagnosis. HPV positive penile cancer incidence significantly increase and the phimosis incidence significantly decrease from 2006 to 2017.

Conclusions: About a half of penile cancers were related to HPV infection. Our findings highlight the phimosis related penile cancers have been declining, the HPV related in the development of penile cancer and a fully aware of regional differences in HPV genotype distribution are tasks for penile cancer control and prevention.

Current management and future perspectives of penile cancer: An updated review

Penile cancer (PeCa) is a rare disease worldwide, accounting for less than one percent of all malignancies in men. It usually presents as a painless ulcer or lump on the head of the penis. Squamous cell carcinoma represents the most common histological subtype of PeCa, with pathogenesis intimately linked to chronic Human Papilloma Virus (HPV) infection. Surgery is the cornerstone for the treatment of primary PeCa with potential mutilating outcome depending on the nodal extension of the disease. However, in case of extensive lymph node involvement, multidisciplinary treatment including perioperative chemotherapy and inclusion in clinical trial should be considered. To date, advanced or metastatic disease still have poor prognosis and are a therapeutic challenge with limited options, highlighting the need of new treatments and further investigations. Growing efforts to identify molecular alterations, understand the role of HPV and characterize immune contexture have expanded over the past years, providing further perspectives in prognostication, predictive biomarkers and therapeutic intervention. In this review, we provide an updated overview of current management of PeCa focusing on perioperative strategy. We discuss about new insights of the biology of PeCa and comment future directions in the field.

Prevalence of human papillomavirus and implication on survival in Chinese penile cancer

We assessed the prevalence of HPV DNA in a large series of Chinese penile cancer and examine its association with the histological subtype, p16^INK4a expression, and prognosis. We pathologically categorized 226 invasive penile squamous cell carcinomas and assessed HPV genotyping by real-time PCR and p16^INK4a immunohistochemistry. The results were correlated with histopathological and clinical parameters and disease-specific survival (DSS). HPV DNA was detected in 32.7% (74/226) of penile cancer cases. The most frequent genotype was HPV 16 (64/74, 86.5%), followed by HPV 18 (6/74, 8.1%). Fifty-nine (26.1%) cases were positive for the p16^INK4a expression, and p16^INK4a expression had a sensitivity of 56.8% (95% CI, 45.2-68.3%) and a specificity of 88.8% (95% CI, 83.8-93.9%) for defining HPV status. HPV DNA (P = 0.019), p16^INK4a (P = 0.038), age (P = 0.018), grade of differentiation (P = 0.001), lymph nodes (P < 0.001), T stage (P < 0.001), M stage (P < 0.001), and lymphovascular invasion (LVI, P = 0.001) were prognostic factors for DSS. HPV-positivity (HR 0.334; 95% CI, 0.158-0.705, P = 0.004) was still a significant prognostic factor for DSS in the multivariate Cox regression model. HPV DNA was observed in one third of Chinese penile carcinoma cases. The p16INK4a expression can indicate high-risk human papillomavirus (HR-HPV). HPV-positive penile tumors confer a survival benefit over HPV-negative tumors.

The relationship between human papillomavirus and penile cancer over the past decade: a systematic review and meta-analysis

Human papillomavirus (HPV) infection appears to play an important role in the development of penile cancer (PeCa), but their relationship remains unclear. Therefore, we performed a systematic review and meta-analysis to elucidate their relationship. We systematically searched Embase, PubMed, Cochrane Library, and Web of Science for case-control studies and cross-sectional studies using polymerase chain reaction (PCR) technology on formalin-fixed paraffin-embedded (FFPE) or paraffin-embedded (PE) PeCa tissues to detect HPV (published between January 1, 2007, and December 29, 2017; no language restrictions). Twenty-two studies were identified, and 1664 cases were available for analysis. The combined HPV infectious risk of PeCa is 51.0% (95% confidence interval [CI]: 43.0%–60.0%). The three most common subtypes of HPV were HPV16 (28.5%), HPV18 (2.3%), and HPV6 (2.3%). The virus was relevantly associated with basaloid (85.5%, 95% CI: 77.2%–93.8%) and warty (50.0%, 95% CI: 35.2%–64.8%) carcinomas. The invasiveness of PeCa was not associated with HPV (χ² = 0.181, df = 1, P < 0.671). HPV infection in PeCa tended to be moderately differentiated (54.4%, 95% CI: 47.7%–61.1%). This study found that almost half of PeCa patients are associated with HPV. The most commonly associated genotype is HPV16, but several other genotypes were also detected. In addition to types 6 and 11, other single low-risk HPV infections have been found to contribute to PeCa to a lesser degree. HPV-positive tumors tend to exhibit warty and/or basaloid features, corresponding to a moderate histological grade. The role of HPV in PeCa should be revisited to provide evidence for the development of PeCa in the presence of HPV infection.

Penile carcinoma and HPV infection (Review)

Penile carcinoma is a relatively frequent health issue in the developing countries such as Africa, Asia and South America, usually affecting men aged between 50 and 70 years. It is a highly treatable disease in its early stages, but has serious physical and psychological consequences. Usually, penile carcinoma is located in the penile glans, in approximately half the cases, with the most frequent histological type being squamous cell carcinoma with its microscopic subtypes. A large number of risk factors have been reported for this disease, having a multifactorial etiology, HPV infection being one of the most important factors involved in its appearance. Out of the HPV DNA positive genital cancers HPV-16 is the most frequently found type in men, followed by HPV-18. The evolution of penile cancer includes two independent carcinogenic pathways, related or unrelated to HPV infection. There is limited data available in literature regarding HPV-related neoplasia, as well as on the efficacy of vaccination in men, with studies still ongoing.

Clear cell carcinoma of the penis

Level of evidence: 5

A Review of Viral-Related Malignancies and the Associated Imaging Findings

OBJECTIVE. Imaging plays an important role in the diagnosis and staging of malignancies. Many common lymphoproliferative and other solid tumor malignancies can be viral-related. CONCLUSION. This review discusses the imaging findings that can be associated with common viral-induced malignancies. Knowledge of these imaging presentations can help narrow the differential diagnosis to reach a specific diagnosis through a precise workup and proper management.

The International Penile Advanced Cancer Trial (InPACT): Rationale and Current Status

The historic international penile cancer trial InPACT is now open and accruing patients in the UK and USA. The trial is geared to answer important questions for patients with evidence of inguinal lymph node disease at presentation. This clinical trial update provides an overview of the study and progress to date.