Human papilloma virus status of penile squamous cell carcinoma is associated with differences in tumour-infiltrating T lymphocytes

Development and validation of HPV-associated and HPV-independent penile squamous cell carcinoma prognostic nomogram

OBJECTIVE

The aim of this study was to introduce HPV-associated and HPV-independent histologic classifications to analyze prognostic factors and develop a prognostic nomogram for patients with penile squamous cell carcinoma (PSCC).

METHODS

Data of 1502 PSCC patients between 2010 and 2020 were accessed from the SEER database, and the patients were randomly divided into a training set and a validation set. Independent risk factors for PSCC patients prognosis were analyzed by using univariate and multivariate COX proportional hazards regression, and was used for the construction of the nomogram, and the predictive performance of the model was evaluated by C-index, calibration curve and ROC curve. Kaplan-Meier analysis was applied to explore the impact of HPV-related factors on patient survival, while propensity score matching (PSM) and inverse probability treatment weighting (IPTW) techniques were used to balance other confounding factors like individual clinical and pathological factors, and to evaluate the differences in overall survival (OS) and cause-specific survival (CSS) between subgroups.

RESULT

The results indicated that histologic type, Grade classification, T/M stage, surgical methods and chemotherapy were independent risk factors affecting OS and CSS in PSCC patients. In addition, age and marital status were significantly associated with OS, while lymph node metastasis was an independent prognostic factor for CSS, the validation results of the model showed that the nomogram had a superior predictive performance compared with the American Joint Committee on Cancer staging system. In addition, subgroup analyses prior to and after IPTW and PSM adjustments showed that HPV-associated group had better OS and CSS than HPV-independent group.

CONCLUSION

Our study developed and validated a nomogram using a novel histologic classification and achieved satisfactory results, which can better help clinicians to predict the prognosis of penile squamous cell carcinoma patients.

High tumour mutational burden is associated with strong PD-L1 expression, HPV negativity, and worse survival in penile squamous cell carcinoma: an analysis of 165 cases

Penile squamous cell carcinoma (pSCC) is a rare tumour with a variable prognosis. More prognostic markers linked to mutational signatures and the tumour immune microenvironment are needed. A cohort made up of 165 invasive pSCC was retrospectively analysed using formalin-fixed, paraffin-embedded tumour tissue, focusing on tumour mutational burden (TMB), programmed death ligand 1 (PD-L1) expression, microsatellite instability (MSI), the number of tumour infiltrating lymphocytes (TILs) expressing cytotoxic T-lymphocyte-associated protein 4 (CTLA4), HPV status determined by p16 immunohistochemistry, and several traditional histopathological variables. High TMB (>10 mut/Mb) was associated with high PD-L1 expression (TPS 50-100%), and HPV-negative status. High PD-L1 expression was linked to HPV negativity, a high number of intratumoural CTLA4+ cells, and brisk lymphocytic infiltrate. High TMB was a significant predictor of shorter overall survival (OS) in both univariate and multivariate analysis when using a median cut-off value of 4.3 mut/Mb, but not when using an arbitrary cut-off of 10 mut/Mb. Low CTLA4+ cell infiltration at the tumour invasion front was a marker of shorter OS and cancer-specific survival in both univariate and multivariate analysis. PD-L1 expression had no significant impact on prognosis. Only two cases were MSI high. The results support the hypothesis of two aetiological pathways in pSCC cancerogenesis: (1) SCC linked to HPV infection characterised by low TMB, less common PD-L1 expression, and a lower number of TILs; and (2) SCC linked to chronic inflammation leading to a high number of acquired mutations (high TMB), HPV negativity, increased neoantigen production (i.e., PD-L1), and high immune cell infiltration.

Characterization of T cell receptor repertoire in penile cancer

Tumor-infiltrating lymphocytes (TILs) play a key role in regulating the host immune response and shaping tumor microenvironment. It has been previously shown that T cell infiltration in penile tumors was associated with clinical outcomes. However, few studies have reported the T cell receptor (TCR) repertoire in patients with penile cancer. In the present study, we evaluated the TCR repertoires in tumor and adjacent normal tissues from 22 patients with penile squamous cell carcinoma (PSCC). Analysis of the T cell receptor beta-variable (TRBV) and joining (TRBJ) genes usage and analysis of complementarity determining region 3 (CDR3) length distribution did not show significant differences between tumor and matched normal tissues. Moreover, analysis of the median Jaccard index indicated a limited overlap of TCR repertoire between these groups. Compared with normal tissues, a significantly lower diversity and higher clonality of TCR repertoire was observed in tumor samples, which was associated with clinical characteristics. Further analysis of transcriptional profiles demonstrated that tumor samples with high clonality showed increased expression of genes associated with CD8 + T cells. In addition, we analyzed the TCR repertoire of CD4 + T cells and CD8 + T cells isolated from tumor tissues. We identified that expanded clonotypes were predominantly in the CD8 + T cell compartment, which presented with an exhausted phenotype. Overall, we comprehensively compared TCR repertoire between penile tumor and normal tissues and demonstrated the presence of distinct T cell immune microenvironments in patients with PSCC.

Human Papillomavirus Infection in Penile Cancer: Multidimensional Mechanisms and Vaccine Strategies

Penile cancer (PC) is a rare male malignant tumor, with early lymph node metastasis and poor prognosis. Human papillomavirus (HPV) plays a key role in the carcinogenesis of PC. This review aims to summarize the association between HPV infection and PC in terms of virus-host genome integration patterns (the disrupted regions in the HPV and PC genome), genetic alterations, and epigenetic regulation (methylation and microRNA modification) occurring in HPV and PC DNA, as well as tumor immune microenvironment reprogramming. In addition, the potential of HPV vaccination strategies for PC prevention and treatment is discussed. Understanding of the HPV-related multidimensional mechanisms and the application of HPV vaccines will promote rational and novel management of PC.

Therapeutic Approaches to Penile Cancer: Standards of Care and Recent Developments

Penile cancer is a rare malignancy, most commonly diagnosed in older men, associated with poor outcomes, dramatic decline in quality of life and sexual function. Squamous cell carcinoma is the most common histopathology of penile cancer, accounting for 95% of all cases. Localized, early-stage penile cancer can be effectively managed through penile-sparing techniques in many cases, though advanced stages of penile cancer carry a poor prognosis. Current innovative treatments are exploring the role of targeted therapy, HPV-directed therapy, immune checkpoint inhibitors and adoptive T-cell therapies in treatment and prevention of relapse of penile cancer. Clinical trials are investigating the potential of targeted therapies and immune checkpoint inhibitors in advanced penile cancer. This review examines the current management of penile cancer and highlights future directions in research and treatment.

Inflammation in Urological Malignancies: The Silent Killer

Several studies have investigated the role of inflammation in promoting tumorigenesis and cancer progression. Neoplastic as well as surrounding stromal and inflammatory cells engage in well-orchestrated reciprocal interactions to establish an inflammatory tumor microenvironment. The tumor-associated inflammatory tissue is highly plastic, capable of continuously modifying its phenotypic and functional characteristics. Accumulating evidence suggests that chronic inflammation plays a critical role in the development of urological cancers. Here, we review the origins of inflammation in urothelial, prostatic, renal, testicular, and penile cancers, focusing on the mechanisms that drive tumor initiation, growth, progression, and metastasis. We also discuss how tumor-associated inflammatory tissue may be a diagnostic marker of clinically significant tumor progression risk and the target for future anti-cancer therapies.

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.

An update on treatment of penile cancer

Penile cancer is a rare malignancy, particularly in industrialized nations. In the United States, rates are approximately less than 1 per 100,000 men per year with just over 2000 new cases per year. However, there is significantly increased prevalence in developing nations, with limited treatment expertise and reduced access to care, further driving an unmet clinical need. The most noteworthy risk factor for penile cancer is the association with human papillomavirus infection, which may be present in up to 50% of all penile carcinomas. In addition to local primary tumor approaches, multimodality treatment strategies are vital to patients with clinical regional nodal disease, locally advanced disease. Presence and degree of lymph node involvement remains the most important prognostic factor and patients may benefit from multiple treatment strategies. Interim analysis data from the first randomized clinical trial is expected to yield results in mid/late 2024–early 2025. These treatment approaches include neoadjuvant chemotherapy, adjuvant therapy, including chemotherapy and radiation. Systemic therapy for distant recurrent or metastatic disease is primarily a platinum-based chemotherapy, however with poor overall response. As poor outcomes remain high, particularly in indigent populations, there remains an unmet need for these patients, particularly for high level randomized trials and novel therapeutics. In this review, we will highlight treatment updates for penile cancer. In addition to standard of care, we will review novel lines of therapies including immunotherapies and targeted therapies as well as sequencing approaches.

Simultaneous and Spatially-Resolved Analysis of T-Lymphocytes, Macrophages and PD-L1 Immune Checkpoint in Rare Cancers

Penile, vulvar and anal neoplasms show an incidence lower than 0.5% of the population per year and therefore can be considered as rare cancers but with a dramatic impact on quality of life and survival. This work describes the experience of a Chilean cancer center using multiplexed immunofluorescence to study a case series of four penile cancers, two anal cancers and one vulvar cancer and simultaneous detection of CD8, CD68, PD-L1, Cytokeratin and Ki-67 in FFPE samples. Fluorescent image analyses were performed using open sources for automated tissue segmentation and cell phenotyping. Our results showed an objective and reliable counting of objects with a single or combined labeling or within a specific tissue compartment. The variability was below 10%, and the correlation between analytical events was 0.92-0.97. Critical cell phenotypes, such as TILs, PD-L1+ or proliferative tumor cells were detected in a supervised and unsupervised manner with a limit of detection of less than 1% of relative abundance. Finally, the observed diversity and abundance of the different cell phenotypes within the tumor microenvironment for the three studied tumor types confirmed that our methodology is useful and robust to be applicable for many other solid tumors.

Tumor-associated immune cell infiltrate density in penile squamous cell carcinomas

Penile squamous cell carcinomas are rare tumor entities throughout Europe. Early lymphonodal spread urges for aggressive therapeutic approaches in advanced tumor stages. Therefore, understanding tumor biology and its microenvironment and correlation with known survival data is of substantial interest in order to establish treatment strategies adapted to the individual patient. Fifty-five therapy naïve squamous cell carcinomas, age range between 41 and 85 years with known clinicopathological data, were investigated with the use of tissue microarrays (TMA) regarding the tumor-associated immune cell infiltrate density (ICID). Slides were stained with antibodies against CD3, CD8 and CD20. An image analysis software was applied for evaluation. Data were correlated with clinicopathological characteristics and overall survival. There was a significant increase of ICID in squamous cell carcinomas of the penis in relation to tumor adjacent physiological tissue. Higher CD3-positive ICID was significantly associated with lower tumor stage in our cohort. The ICID was not associated with overall survival. Our data sharpens the view on tumor-associated immune cell infiltrate in penile squamous cell carcinomas with an unbiased digital and automated cell count. Further investigations on the immune cell infiltrate and its prognostic and possible therapeutic impact are needed.

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.

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.

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.

Penile cancer

Penile squamous cell carcinoma (PSCC) is a rare cancer with orphan disease designation and a prevalence of 0.1-1 per 100,000 men in high-income countries, but it constitutes up to 10% of malignancies in men in some African, Asian and South American regions. Risk factors for PSCC include the absence of childhood circumcision, phimosis, chronic inflammation, poor penile hygiene, smoking, immunosuppression and infection with human papillomavirus (HPV). Several different subtypes of HPV-related and non-HPV-related penile cancers have been described, which also have different prognostic profiles. Localized disease can be effectively managed by topical therapy, surgery or radiotherapy. As PSCC is characterized by early lymphatic spread and imaging is inadequate for the detection of micrometastatic disease, correct and upfront surgical staging of the inguinal lymph nodes is crucial in disease management. Advanced stages of disease require multimodal management. Optimal sequencing of treatments and patient selection are still being investigated. Cisplatin-based chemotherapy regimens are the mainstay of systemic therapy for advanced PSCC, but they have poor and non-durable responses and high rates of toxic effects, indicating a need for the development of more effective and less toxic therapeutic options. Localized and advanced penile cancers and their treatment have profound physical and psychosexual effects on the quality of life of patients and survivors by altering sexual and urinary function and causing lymphoedema.

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.

Immunophenotypes Based on the Tumor Immune Microenvironment Allow for Unsupervised Penile Cancer Patient Stratification

The tumor immune microenvironment (TIME) plays an important role in penile squamous cell carcinoma (peSCC) pathogenesis. Here, the immunophenotype of the TIME in peSCC was determined by integrating the expression patterns of immune checkpoints (programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1), cytotoxic T lymphocyte antigen 4 (CTLA-4), and Siglec-15) and the components of tumor-infiltrating lymphocytes, including CD8⁺ or Granzyme B⁺ T cells, FOXP3⁺ regulatory T cells, and CD68⁺ or CD206⁺ macrophages, in 178 patients. A high density of Granzyme B, FOXP3, CD68, CD206, PD-1, and CTLA-4 was associated with better disease-specific survival (DSS). The patients with diffuse PD-L1 tumor cell expression had worse prognoses than those with marginal or negative PD-L1 expression. Four immunophenotypes were identified by unsupervised clustering analysis, based on certain immune markers, which were associated with DSS and lymph node metastasis (LNM) in peSCC. There was no significant relationship between the immunophenotypes and high-risk human papillomavirus (hrHPV) infection. However, the hrHPV–positive peSCC exhibited a higher density of stromal Granzyme B and intratumoral PD-1 than the hrHPV–negative tumors (p = 0.049 and 0.002, respectively). In conclusion, the immunophenotypes of peSCC were of great value in predicting LNM and prognosis, and may provide support for clinical stratification management and immunotherapy intervention.

Human Papillomavirus, MicroRNA and their Role in Cervical Cancer Progression, Diagnosis and Treatment Response: A Comprehensive Review

Human Papillomavirus (HPV) is sexually transmitted and linked with vaginal, vulvar and cervix cancers in females, penile cancer in male, while anal and oropharyngeal cancer in both genders. Cervical cancer is ranked as third most identified cancer among females globally and is the fourth leading reason of cancer related mortality. The main aim of current study is to highlight the key role of miRNA in cervical cancer development, progression and their therapeutic responses. Current study entailed more than 50 PubMed cited articles related to miRNA role in cervical cancer. Studies have elucidated the role of miRNAs regulation in gene expression at post-transcriptional and translational level by targeting significant genes and therefore involved in cervical cancer. miRNAs control several cellular pathways involved in development of pre-malignant to metastatic stage and proliferation to malignancy. Current review elucidated and elaborated the key role of miRNA their application, treatment and therapeutic responses in cervical cancer.

Management of clinically node-negative groin in patients with penile cancer

Malignant penile neoplasms are commonly squamous etiology, with the inguinal nodes being the first echelon of spread. The disease spreads to the pelvic lymph nodes only after metastases to the groin nodes, and this is the most important prognostic factor in penile carcinoma. While treatment of penile carcinoma with proven metastases to the inguinal lymph nodes mandates ilioinguinal lymph node dissection, the treatment of patients with impalpable nodes is more controversial. Overtreatment leads to excessive treatment-related morbidity in these patients, while a wait-and-see policy runs the risk of patients presenting with inguinal and distant metastases, which would have been curable at presentation. Unfortunately, no single imaging modality has been proved to be convincingly superior in the staging, and hence, management of the clinically negative groin has been subject to debate. While some high volume centers have promoted the use of dynamic sentinel lymph node biopsy, others advocate the use of the modified inguinal lymph node template to stage the groin adequately. Newer techniques such as video endoscopic inguinal lymph node dissection have been introduced as an alternative to the original radical inguinal lymphadenectomy to reduce morbidity.

Morphology, p16, HPV, and outcomes in squamous cell carcinoma of the penis: a multi-institutional study

Our objective was to evaluate the pathologic features and clinical outcomes in cases of invasive penile squamous cell carcinoma (SCC) and the association with p16 immunohistochemistry (IHC) and human papilloma virus (HPV) in situ hybridization (ISH). A retrospective multi-institutional database search was conducted for invasive SCC of the penis diagnosed between 2007 and 2018 that had undergone surgical resection. Pathologic features, p16 IHC, and HPV ISH were investigated with clinical outcomes. A total of 102 patients were included in the study. The average age was 63 ± 13.3 years. Based on histology, 46% of tumors displayed an HPV-related subtype, whereas p16 was positive in 52% of all cases. Tumor histology correlated well with p16 positivity (P < .001), and p16 IHC accurately predicted the presence of HPV in 25/26 (96%) cases. On multivariate analysis, perineural invasion was associated with local disease recurrence (P = .02), whereas lymphovascular invasion was associated with progression to metastatic disease (P = .002) and increased overall mortality (P = .02). Urethral involvement was also associated with increased overall mortality (P = .02). In addition, HPV-related tumors based on histologic features correlated with lower rates of metastatic disease (P = .007). HPV is a common cause of penile SCC and can be diagnosed by tumor histology and confirmed by overexpression of p16 on IHC. The presence of lymphovascular invasion, perineural invasion, and urethral involvement are poor prognostic indicators, whereas HPV-related tumors based on histology may have lower risk for metastatic disease.

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 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.

Contemporary management of patients with penile cancer and lymph node metastasis

Penile cancer is a rare disease that causes considerable physical and psychological patient morbidity, especially at advanced stages. Patients with low-stage nodal metastasis can achieve durable survival with surgery alone, but those with extensive locoregional metastasis have overall low survival. Contemporary management strategies for lymph node involvement in penile cancer aim to minimize the morbidity associated with traditional radical inguinal lymphadenectomy through appropriate risk stratification while optimizing oncological outcomes. Modified (or superficial) inguinal lymph node dissection and dynamic sentinel lymph node biopsy are diagnostic modalities that have been recommended in patients with high-risk primary penile tumours and nonpalpable inguinal lymph nodes. In addition, advances in minimally invasive and robot-assisted lymphadenectomy techniques are being investigated in patients with penile cancer and might further decrease lymphadenectomy-related adverse effects. The management of patients with advanced disease has evolved to include multimodal treatment with systemic chemotherapy before surgical intervention and can include adjuvant chemotherapy after pelvic lymphadenectomy. The role of radiotherapy in the neoadjuvant or adjuvant setting remains largely unclear, owing to a lack of high-level evidence of possible benefits. New targeted therapies have shown efficacy in squamous cell carcinomas of other sites and might also prove effective in patients with penile cancer.

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.