Defining the Tumor Microenvironment of Penile Cancer by Means of the Cancer Immunogram

Smoking and presence of human papillomavirus correlates with lymphocyte density in the stroma of penile squamous cell carcinoma

Background

Penile squamous cell carcinoma (PSCC) is the most common malignancy of the penis. Considering the increase in incidence of PSCC in many countries, there is a need for better and effective therapies for these patients. The tumor microenvironment may offer insights into a better understanding of the tumor, which may inform on predictive and prognostic targets. In this study, we investigated immune cell infiltration into the stroma of PSCC, and how it may be affected by multiple factors including smoking, HIV infection, and/or HPV infection.

Methods

We carried out a prospective analytical cross-sectional study at the University Teaching Hospital in Lusaka, Zambia. Consenting patients with confirmed PSCC, attending the Urology Clinic and scheduled for partial or total penectomy were enrolled into the study. HIV testing by serology, HPV detection and genotyping on fresh tumors by real time PCR, hematoxylin and eosin (H&E) staining and immunohistochemistry staining for CD3+ and CD8+ cells on formalin-fixed paraffin-embedded tissue, and flow cytometry for immunophenotyping circulating immune cells were done.

Results

We enrolled 33 participants into the study. The participants had a mean age of 56 years, the majority (84.8%) were HIV positive, high-risk HPV was detected in 63.6% of the tumors, and 57.6% were positive for both HIV and high-risk HPV. HPV-positive PSCC tumors had a significantly lower proportion of infiltrating lymphocytes in the stroma on H&E staining than HPV-negative tumors [18% vs 53%; p=0.025]. Smokers had a significantly lower number of infiltrating CD8+ cells in the stroma than non-smokers [68 vs 99; p=0.035]. No difference in the density of stromal lymphocytes between HPV/HIV co-infected and non-co-infected individuals was observed. There was a statistically significant positive correlation in number of CD3+ (⍴=0.38; p=0.027) and CD8+ (⍴=0.40; p=0.02) cells in the stroma and intra-tumor. Factors including histological stage, tumor grade, HPV status, and HIV status seem to influence the correlation in number of stroma and intra-tumoral immune cells.

Conclusion

Smoking and presence of hrHPV is associated with a lower density of infiltrating lymphocytes in the stroma of PSCC. There is a positive correlation in the number of CD3+ and CD8+ cells between the stroma and intra-tumoral compartment of PSCC.

Role of PD-1/PD-L1 signaling axis in oncogenesis and its targeting by bioactive natural compounds for cancer immunotherapy

Cancer is a global health problem and one of the leading causes of mortality. Immune checkpoint inhibitors have revolutionized the field of oncology, emerging as a powerful treatment strategy. A key pathway that has garnered considerable attention is programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1). The interaction between PD-L1 expressed on tumor cells and PD-1 reduces the innate immune response and thus compromises the capability of the body's immune system. Furthermore, it controls the phenotype and functionality of innate and adaptive immune components. A range of monoclonal antibodies, including avelumab, atezolizumab, camrelizumab, dostarlimab, durvalumab, sinitilimab, toripalimab, and zimberelimab, have been developed for targeting the interaction between PD-1 and PD-L1. These agents can induce a broad spectrum of autoimmune-like complications that may affect any organ system. Recent studies have focused on the effect of various natural compounds that inhibit immune checkpoints. This could contribute to the existing arsenal of anticancer drugs. Several bioactive natural agents have been shown to affect the PD-1/PD-L1 signaling axis, promoting tumor cell apoptosis, influencing cell proliferation, and eventually leading to tumor cell death and inhibiting cancer progression. However, there is a substantial knowledge gap regarding the role of different natural compounds targeting PD-1 in the context of cancer. Hence, this review aims to provide a common connection between PD-1/PD-L1 blockade and the anticancer effects of distinct natural molecules. Moreover, the primary focus will be on the underlying mechanism of action as well as the clinical efficacy of bioactive molecules. Current challenges along with the scope of future research directions targeting PD-1/PD-L1 interactions through natural substances are also discussed.

LncRNA sequencing reveals an essential role for the lncRNA-mediated ceRNA network in penile squamous cell carcinoma

Penile squamous cell carcinoma (PSCC) is becoming increasingly common and posing a severe threat to men's health, particularly in developing countries. The function of long non-coding RNAs (lncRNAs) in PSCC progression remains mysterious. Therefore, we explored the significance of lncRNAs in the competing endogenous RNA (ceRNA) network in PSCC tumor progression. The 5 healthy and 6 tumor tissue samples were subjected to lncRNA sequencing. Using miRcode, LncBase, miRTarBase, miRWalk, and TargetScan, we constructed a ceRNA network of differentially expressed lncRNAs, miRNAs, and mRNAs. Our analysis resulted in a ceRNA network consisting of 4 lncRNAs, 18 miRNAs, and 38 mRNAs, whose upstream regulators, the lncRNAs MIR205HG, MIAT, HCP5, and PVT1, were all elevated in PSCC. Immunohistochemical staining confirmed that cell proliferation-related genes TFAP2C, MKI67, and TP63, positively regulated by 4 lncRNAs, were considerably overexpressed in tumor tissues. Immune analysis revealed a significant upregulation in macrophage and exhausted T cell infiltration in PSCC. Our study identified a lncRNA-miRNA-mRNA ceRNA network for PSCC, revealing possible molecular mechanisms involved in the regulation of PSCC progression by key lncRNAs and their connections to the immunosuppressive tumor microenvironment. The ceRNA network provides a novel perspective for elucidating the pathogenesis of PSCC.

What is the relationship between penile cancer and the microbiome? A scoping review

INTRODUCTION

The microbiota is defined as the microorganisms in a particular environment. Conversely, the term microbiome is less firmly defined and is used to reference the habitat.

OBJECTIVE

To identify the association between the microbiome and the penile cancer EVIDENCE ACQUISITION: We performed this scoping review according to the recommendations of the Joanna Briggs Institute. We found five articles that fulfilled the inclusion criteria. We focused on oncogenesis and factors that alter the penile microbiome. We were not limited to language or setting. We searched MEDLINE (Ovid), Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and LILACS from inception to the present day.

EVIDENCE SYNTHESIS

We found nine studies describing multiple factors that could disturb the microbiome, such as sexual behavior, anatomic alterations including circumcision, and inflammatory factors: lichen sclerosus, poor genital hygiene, compromised immune system, smoking, and HPV infection.

CONCLUSION

Overall, knowledge of the composition of the penile microbiota and its role in penile cancer oncogenesis is minimal.

PATIENT SUMMARY

Future studies should focus on the relationship between the microbiome and penile cancer to broaden this field of knowledge.

Immune-based Therapies for Penile Cancer

This article reviews penile squamous cell carcinoma (PSCC), a rare genitourinary cancer that has been increasing in prevalence. It discusses emerging therapies, focusing on immunotherapy, vaccine therapy, and cell-based treatments, especially in the context of human papillomavirus-related PSCC. Factors influencing these therapies are discussed. These include the immune microenvironment, programmed cell death ligand-1 expression, and tumor immune cell infiltration. This article also highlights immune checkpoint inhibitors and related clinical trials. This review supports the use of personalized medicine in treating PSCC. It stresses the need for collaborative studies and data sharing to create specific treatment plans and achieve better outcomes.

Advances in molecular basis of response to immunotherapy for penile cancer: better screening of responders

Penile cancer is a rare malignant tumor of the male urinary system. The treatment benefit of standard first-line chemotherapy is not ideal for patients with locally advanced or metastatic lymph nodes. Immunotherapy has brought new treatment strategies and opportunities for patients with penile cancer. At present, clinical studies on immunotherapy for penile cancer have been reported, and the results show that it is effective but not conclusive. With the development of immunotherapy and the progress of molecular research technology, we can better screen the immunotherapy response population and explore new combination treatment regimens to evaluate the best combination regimen and obtain the optimal treatment options, which is also an important research direction for the immunotherapy of penile cancer in the future.

Cemiplimab as First Line Therapy in Advanced Penile Squamous Cell Carcinoma: A Real-World Experience

In the treatment of cancer, immune checkpoint inhibitors (ICIs) have demonstrated significantly greater effectiveness compared to conventional cytotoxic or platinum-based chemotherapies. To assess the efficacy of ICI's in penile squamous cell carcinoma (pSCC) we performed a retrospective observational study. We reviewed electronic medical records of patients with penile squamous cell carcinoma (SCC), diagnosed between January 2020 and February 2023. Nine patients were screened, of whom three were ineligible for chemotherapy and received immunotherapy, cemiplimab, in a first-line setting. Each of the three immunotherapy-treated patients achieved almost a complete response (CR) after only a few cycles of therapy. The first patient had cerebral arteritis during treatment and received a high-dose steroid treatment with resolution of the symptoms of arteritis. After tapering down the steroids dose, the patient continued cemiplimab without further toxicity. The other two patients did not have any toxic side effects of the treatment. To the best of our knowledge, this is the first real world report of near CR with cemiplimab as a first-line treatment in penile SCC.

Atezolizumab With or Without Radiotherapy for Advanced Squamous Cell Carcinoma of the Penis (The PERICLES Study): A Phase II Trial

PURPOSE

Patients with advanced penile squamous cell carcinoma have a poor prognosis (21% 2-year overall survival [OS] from diagnosis). We assessed the activity of atezolizumab (anti-PD-L1) in patients with advanced penile cancer, with or without radiotherapy (RT).

PATIENTS AND METHODS

A single-center, nonrandomized phase II study with two treatment arms was conducted in 32 patients with histologically confirmed advanced penile cancer. All patients received atezolizumab (1,200 mg) once every 3 weeks. Twenty patients, who were expected to benefit from RT for locoregional disease control, received additional irradiation. The primary end point was 1-year progression-free survival (PFS) for the complete cohort and was reached if the actual 1-year PFS was at least 35%. Secondary end points included OS, objective response rate (ORR), and tolerability. Exploratory biomarker analyses were conducted in pretreatment specimens.

RESULTS

Median follow-up was 29.1 months (IQR, 18.1-33.5). Grade 3-4 adverse events related to atezolizumab or RT were observed in 3/32 (9.4%) and 13/20 (65%) patients, respectively. One-year PFS was 12.5% (95% CI, 5.0 to 31.3), which did not meet the study's primary end point. Median OS was 11.3 months (95% CI, 5.5 to 18.7). In the objective response-evaluable population (n = 30; 93.8%), the ORR was 16.7% (95% CI, 6 to 35), including 2 (6.7%) complete responders and 3 (10%) partial responders. Improved PFS was observed in patients with high-risk human papillomavirus (hrHPV)-positive tumors (P = .003) and those with high infiltration of intratumoral CD3+CD8+ T cells (P = .037).

CONCLUSION

Although the primary end point of 1-year PFS was not met, durable antitumor activity to atezolizumab was observed in a subset of patients. Biomarkers, such as hrHPV and intratumoral CD3+CD8+ T-cell infiltration, may help to better select responders.

First-line programmed death receptor-1 (PD-1) inhibitor and epidermal growth factor receptor (EGFR) blockade, combined with platinum-based chemotherapy, for stage IV penile cancer

OBJECTIVES

To evaluate the anti-tumour activity and safety of anti-programmed death receptor-1 (PD-1) antibody plus epidermal growth factor receptor blockade combined with platinum-based chemotherapy (PEP) as first-line therapy for stage IV penile squamous cell carcinoma (PSCC).

PATIENTS AND METHODS

We conducted a retrospective review of 17 patients with stage IV PSCC undergoing first-line PEP at Sun Yat-sen University Cancer Center between January 2018 and September 2021. Clinical responses were assessed using the Response Evaluation Criteria in Solid Tumours (RECIST) version 1.1. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Adverse events (AEs) were graded according to Common Terminology Criteria for Adverse Events version 5.0.

RESULTS

Of 17 patients who received first-line PEP, 13 were observed to have partial responses. Twelve patients subsequently received consolidated surgery. Nine of these achieved pN0 status, of whom six with locally advanced PSCC achieved pathological complete response. The median (range) follow-up time was 24.87 (3.63-29.40) months. Median PFS and median OS were not reached, with 2-year PFS and OS rates being 68.4% (95% confidence interval [CI] 48.7-96.1) and 62.9% (95% CI 41.6-95), respectively. Eight patients experienced Grade 3 or 4 treatment-related AEs. No Grade 5 AEs or death associated with treatment was observed.

CONCLUSIONS

Anti-PD-1 antibody plus epidermal growth factor receptor blockade and platinum-based chemotherapy showed promising anti-tumour activity, acceptable toxicity, and satisfying long-term survival for stage IV PSCC. Larger clinical trials are needed to validate our findings.

PD-L1 is associated with the prognosis of penile cancer: A systematic review and meta-analysis

BACKGROUND

Previous studies have explored the role of PD-L1 in the survival outcomes of penile cancer patients with controversies existed. Thus, the meta-analysis was conducted to report and review the association between PD-L1 and survival in penile cancer patients.

METHODS

PubMed, Cochrane Library, EMBASE, and Web of Science were all searched, screened, and reviewed by June 1, 2022. Hazard ratio (HR) was used to evaluate the relationship between PD-L1 and survival outcome, and odds ratio (OR) was for tumor features.

RESULTS

Nine retrospective studies (1,003 patients) were incorporated. The prevalence of PD-L1 in patients with penile cancer was 51.4% (95% CI = 42.1%-60.8%, I 2 = 88.5%). Higher PD-L1 on tumor cells was related to shorter cancer-specific survival (CSS) in patients (HR = 1.578, 95% CI = 1.227-2.029, I 2 = 23.3%), but had no associations with overall survival (OS) (HR = 1.123, 95% CI = 0.511-2.465, I 2 = 0.0%). Subgroup analysis indicated that higher PD-L1 was related to shorter CSS in Caucasus (HR = 1.827, 95% CI = 1.355-2.465, I 2 = 0.0%) only. Furthermore, PD-L1 had associations with tumor stage (pT1 vs. pT2-4, OR = 0.480, 95% CI = 0.346-0.667, P = 0.001) and tumor grade (Well and moderate vs. Poor, OR = 0.377, 95% CI = 0.264-0.538, P < 0.001). PD-L1 positivity was also related to lymph node (LN) status (pN0/NX vs. pN1-3, OR = 0.541, 95% CI = 0.385-0.759, P = 0.001) and HPV status (Positive vs. Negative, OR = 0.510, 95% CI = 0.322-0.810, P = 0.003). A trend toward statistical significance between PD-L1 and histological types was also observed (Usual SCC vs. Others, OR = 1.754, 95% CI = 0.984-3.124, P = 0.070).

CONCLUSIONS

PD-L1 over-expression was related to worse survival outcomes and several clinicopathological features of penile cancer. PD-L1 expression can be applied to select appropriate treatment strategies for penile malignancies.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=343041, identifier CRD42022343041.

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.

Immunotherapy in Genitourinary Malignancy: Evolution in Revolution or Revolution in Evolution

Immunotherapy, the 5th pillar of cancer care after surgery, radiotherapy, cytotoxic chemotherapy, and precision therapy (molecular targeted therapy), is revolutionizing the standard of care in certain patients with genitourinary malignancies. As modest clinical benefits of IL-2 for metastatic renal cell carcinoma and Bacillus Calmette-Guerin therapy for early-stage bladder cancers in the past years, immune checkpoint inhibitors therapies demonstrate meaningful survival benefit and durable clinical response in renal cell carcinoma, urothelial carcinoma, and some prostate cancer. Despite best efforts, the benefits are limited to a minority of unselected patients due to the complexities of biomarker development. Now come the next hurdles: figuring out which patients best respond to immune checkpoint inhibitors and which patients won't respond to immune checkpoint inhibitors? How best to approach immune checkpoint inhibitors therapies to extend/maximize the treatment response as long as possible? How to overcome therapeutic resistance by specific concurrent immunomodulators or targeted therapy or chemotherapy? The role of immune checkpoint inhibitors in combination or sequencing with chemotherapy or other targeted therapies or other immunomodulating therapeutics in the early disease, neoadjuvant, adjuvant, and metastatic setting is actively under exploration. Ideal strategy for cancer care is to provide not just more time, but more quality time: there remain unmet needs for novel therapies that exploit molecular or genetic pathways to extend survival without compromising health-related quality of life for patients with advanced genitourinary malignancies. Further research is needed to discover new therapeutic strategies, and validate efficacy and effectiveness in real-world settings.

Efficacy and Biomarker Exploration of Sintilimab Combined With Chemotherapy in the Treatment of Advanced Penile Squamous Cell Carcinoma-A Report of Two Cases

Penile squamous cell carcinoma is a rare malignant tumor of the male reproductive system. We report two cases of advanced penile squamous cell carcinoma with persistent partial response/complete response after sintilimab combined with chemotherapy and analyze the relevant tumor biomarkers.

BIRC5 regulates inflammatory tumor microenvironment-induced aggravation of penile cancer development in vitro and in vivo

Background

Baculoviral IAP repeat containing 5 (BIRC5) is overexpressed and plays as a key regulator in the progression of various human carcinomas. The inflammatory tumor microenvironment (ITM) is closely associated with the development of cancers. However, the role of BIRC5 in penile cancer (PC) and the ITM-induced abnormal progression of PC is still obscure.

Methods

In this study, serum and tissues of patients with PC were recruited to evaluate the expression profile of BIRC5. We used PC cell lines (Penl1 and Penl2) and constructed a PC xenograft mice model to explore the effects of the silencing of BIRC5 on proliferation, migration, invasion and tumor growth, as well as survival of mice. Besides, interferon (IFN)-γ was utilized to mimic the ITM of PC cells.

Results

Our results showed that BIRC5 was dramatically upregulated in the serum and tissues of PC patients, as well as PC cell lines. Knockdown of BIRC5 inhibited the proliferation, migration and invasion of PC cells. Meanwhile, it suppressed PC xenograft tumor growth and improved mice survival. Moreover, IFN-γ significantly aggravated PC progression both in vivo and in vitro while the silencing of BIRC5 reversed these unfavorable effects.

Conclusions

Taken together, our data revealed that BIRC5 silencing inhibited aggravation of PC cell processes and tumor development induced by ITM. This suggested that BIRC5 may function as a diagnosis and therapy target of PC in the future.

The peri- and intratumoral immune cell infiltrate and PD-L1 status in invasive squamous cell carcinomas of the penis

INTRODUCTION

Penile carcinomas are rare tumors throughout Europe. Therefore, little attention is drawn to this disease. That makes it important to study tumor-associated key metrics and relate these to known data on penile neoplasias.

MATERIALS AND METHODS

A cohort of 60 well-defined penile invasive carcinomas with known human papillomavirus (HPV) infection status was investigated. Data on tumor type, grading and staging were recorded. Additionally, data on the peri- and intratumoral immune cell infiltrate in a semiquanititave manner applying an HE stain were assessed.

RESULTS

Our study showed a significant correlation of immune cell infiltrate and pT stage with overall survival. Therefore, in a subset of tumors, PD-L1 staining was applied. For tumor proportion score (TPS), 26 of 30 samples (87%) were scored >0%. For the immune cell score (IC), 28 of 30 samples (93%) were defined as >0% and for CPS, 29 of 30 samples (97%) scored >0. PD-L1 expression was not associated with overall survival.

CONCLUSION

PD-L1 is expressed in penile carcinomas, providing a rationale for targeted therapy with checkpoint inhibitors. We were able to show that immune reaction appears to be prognostically relevant. These data enhance the need for further studies on the immune cell infiltrate in penile neoplasias and show that PD-L1 expression is existent in our cohort, which may be a potential target for checkpoint inhibitor therapy.

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.

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.

The Immune Microenvironment in Penile Cancer and Rationale for Immunotherapy

Penile cancer is an extremely rare malignancy that accounts for approximately 1% of cancer deaths in the United States every year. While primary penile cancer can be managed surgically, advanced and metastatic forms of the disease require more aggressive management plans with systemic chemotherapy and/or radiotherapy. Despite the meaningful response to systemic treatments, the 2-year progression-free survival and disease-specific survival have shown disappointing results. Therefore, there is a crucial need for alternative treatment options with more favorable outcomes and a lower toxicity profile. There are currently extensive studies of tumor molecular biology and clinical trials with targeted molecular therapies, such as PD-1, PD-L1, and CTLA-4. In this review, we will describe the penile cancer microenvironment, and summarize the rationale for immunotherapy in penile cancer patients.

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.

Recurrent Metastatic Penile Cancer Patient with Positive PD-L1 Expression Obtained Significant Benefit from Immunotherapy: A Case Report and Literature Review

Background

Penile squamous cell carcinoma (PSCC) bears poor prognosis due to its rarity and limited treatment options, especially after failure of standard treatments. Effective therapeutic options were desperately needed.

Case Presentation

We report a recurrent metastatic PSCC patient with positive programmed death ligand 1 (PD-L1) expression (≥10%) and tumor mutation burden (TMB) of 8.87 (Muts/Mb) who obtained significant response to immunotherapy, with progression-free survival (PFS) exceeding 10 months.

Conclusion

This is the first case presenting remarkable response to immunotherapy in a Chinese PSCC patient. The remarkable response might be associated with PD-L1 expression, indicating that PD-L1 expression could be a promising biomarker for immunotherapy in PSCC. TMB ranking may also contribute to patient selection. However, large clinical trials are needed to validate these notions.