Human Papilloma Virus (HPV) status may impact treatment outcomes in patients with pre-cancerous penile lesions (an eUROGEN Study)

Retrospective clinical and molecular characterisation of patients with penile intraepithelial neoplasia

OBJECTIVES

To provide the first comprehensive molecular characterisation of penile intraepithelial neoplasia (PeIN) and to define the molecular alterations and clinical parameters associated with recurrence in order to enhance our ability to manage this disease.

PATIENTS AND METHODS

We conducted a retrospective audit of records and an analysis of archived formalin-fixed paraffin-embedded (FFPE) tissue from a single-centre population-based consecutive sample, to characterise the genetic landscape of 28 PeIN patients through DNA copy number analysis, RNA expression analysis, and gene set enrichment analysis (GSEA). The primary and secondary study outcomes were alterations in the genetic landscape of recurring vs non-recurring PeIN and clinical risk factors for recurrence.

RESULTS

In patients with PeIN recurrence, we identified seven significantly overexpressed genes (e.g., MYC, SCN8A and PSTK). Importantly, in the DNA analysis, the MYC locus was amplified (8q24.12-8q24.22 gain), the RNA analysis showed overexpression of MYC, and the MYC pathways (GSEA) were enriched compared to patients without PeIN recurrence. Limitations of the study include treatment heterogeneity and FFPE specimens challenging for RNA quality.

CONCLUSION

We identified seven overexpressed genes in patients with PeIN recurrence. Some of these transcripts were previously reported to be involved in invasive penile cancer. These findings provide molecular evidence, that PeIN is a precursor lesion with a correlation to invasive penile cancer, and could potentially lead to new topical treatment strategies for PeIN and low-risk penile cancer.

Risk of invasive penile cancer after treatment of penile intraepithelial neoplasia

OBJECTIVES

To examine the risk of progression and time to progression from penile intraepithelial neoplasia (PeIN) to invasive penile cancer in patients treated for PeIN with either surgery, laser ablation or topical treatment, and to examine recurrence risk after treatment of PeIN.

PATIENTS AND METHODS

Data on patients diagnosed with PeIN (n = 1122) between 2000 and 2020 were extracted from the Swedish National Penile Cancer Registry (NPECR). Progression was defined as a second registration of invasive penile cancer in this registry. Additionally, patient charts from the three largest cities in Sweden (Stockholm, Gothenburg and Malmö) were analysed with regard to both progression of PeIN to invasive cancer and recurrence risk after treatment.

RESULTS

The NPECR included 1122 patients with PeIN, of whom 23 were re-registered as having invasive penile cancer. In the 927 PeIN patients for whom data on treatment were available, re-registration of invasive cancer was seen in 13 patients after surgery, six after laser ablation, and one after topical treatment. The progression-free probabilities at 24 months in these treatment groups were 99.3% (95% confidence interval [CI] 0.987; 0.999), 100% (95% CI 1.000; 1.000) and 98.8% (95% CI 0.965; 1.000), respectively (log-rank test P = 0.192). In the Stockholm, Gothenburg and Malmö cohort, 253 patients with PeIN were followed and 14 developed invasive penile cancer. Of the 247 PeIN cases with data on treatment, four progressed after surgery, eight after laser ablation, and one after topical treatment. The progression-free probabilities at 24 months in these treatment groups were 98.2% (95% CI 0.956; 1.000), 86.2% (95% CI 0.744; 0.997) and 100% (95% CI 1.000; 1.000), respectively (log-rank test P < 0.001).

CONCLUSION

We found that PeIN has a low risk of progressing into invasive penile cancer regardless of treatment modality. However, laser ablation therapy is not recommended due to a higher risk of progression after such treatment compared to surgical and topical treatment. We recommend individualised follow-up protocols of PeIN based on treatment and lesion location.

Multicenter Evaluation of Morbidity and Predictors of Response to Imiquimod Treatment for Penile Intraepithelial Neoplasia

Introduction and objective

Imiquimod (IQ) is an immunomodulator used in the management of penile intraepithelial neoplasia (PeIN) lesions. However, IQ treatment may be associated with bothersome side effects (SEs). To date, studies reporting on this morbidity and evaluating predictors of response to IQ are scarce and included small cohorts. The primary objective of our study was to assess the response to IQ treatment, associated SEs, and potential predictors of response in the largest reported cohort to date.

Methods

We conducted a collaborative retrospective study involving patients diagnosed with PeIN and treated with IQ between 2010 and 2022 in two high-volume centers in the Netherlands and Belgium. Eligible patients had a confirmed diagnosis of PeIN and a minimum of 6-mo follow-up. Response to IQ was categorized as a complete response (CR), partial response, or no response. Descriptive statistics were generated and statistical tests included the Mann-Whitney U test for age and Fisher's exact test for categorical variables.

Key findings and limitations

The study included a total of 44 patients, with a median age of 65.4 yr (interquartile range 56-72). Of these patients, 28 (64%) achieved a CR, while 14 (32%) had a partial response and two (4.5%) had no response. In the CR subgroup, the 3-yr recurrence rate was 25%. No significant correlation was found between response status and age, human papillomavirus status, history of penile cancer, or circumcision before treatment. Among the patients, 50% reported SEs, mainly local pain, irritation, and bleeding, and 12% discontinued treatment because of SEs. There was no significant correlation between CR and the incidence or type of SE.

Conclusions and clinical implications

Despite the high overall response rate to IQ, a significant number of patients experienced local recurrence within 3 yr, and approximately half of the patients reported SEs. Our results did not identify any clinical or pathological factors or local SEs predictive of the therapeutic response to IQ. Prospective studies are needed to help in predicting which patients are likely to respond to IQ so that those who will not benefit can be spared the SEs associated with this treatment.

Patient summary

Our study looked at responses to imiquimod (IQ), an immune-based treatment in cream format, for precancerous lesions on the penis, called penile intraepithelial neoplasia. More than 95% of patients had a complete or partial response to IQ, but 50% reported side effects, and 25% of the group with a complete response had recurrence within 3 years. More research is needed to help in selecting patients who will benefit the most from IQ treatment.

Penile intraepithelial neoplasia incidence, clinical classification, microenvironment and implications for imiquimod treatment

OBJECTIVES

To provide an outline of the existing data on penile intraepithelial neoplasia (PeIN), as well as a narrative review on imiquimod (IQ; a toll-like receptor 7 agonist) treatment and immune microenvironment markers that may predict response to treatment.

METHODS

A narrative review of the literature from 2000 to the present was conducted on PubMed, and we describe the most relevant data and cross references.

RESULTS

The incidence of PeIN is increasing. Local therapy with IQ may offer an easy applicable treatment with complete response rates of up to 63% but can be associated with considerable side-effects. There is no conclusive data on the optimal treatment schedule for PeIN, but evaluation of treatment results for other human papillomavirus-related pre-malignancies suggest three times a week for a duration up to 16 weeks. There are no published studies concerning the PeIN immune microenvironment. However, findings from the few studies on penile cancer and pre-cancerous vulvar and cervical lesions imply that specific immune cell subpopulations can serve as future predictors for successful immunomodulation treatments such as IQ.

CONCLUSIONS

Overall, limited data are available on IQ treatment for PeIN and no published data exists on the PeIN immune microenvironment. Further translational studies are warranted to gain more understanding on the pathophysiology of PeIN and potential predictors of progression and of response to topical treatments.

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.

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.

European Association of Urology-American Society of Clinical Oncology Collaborative Guideline on Penile Cancer: 2023 Update

CONTEXT

Penile cancer is a rare disease but has a significant impact on quality of life. Its incidence is increasing, so it is important to include new and relevant evidence in clinical practice guidelines.

OBJECTIVE

To provide a collaborative guideline that offers worldwide physician and patient guidance for the management of penile cancer.

EVIDENCE ACQUISITION

Comprehensive literature searches were performed for each section topic. In addition, three systematic reviews were conducted. Levels of evidence were assessed, and a strength rating for each recommendation was assigned according to the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) methodology.

EVIDENCE SYNTHESIS

Penile cancer is a rare disease but its global incidence is increasing. Human papillomavirus (HPV) is the main risk factor for penile cancer and pathology should include an assessment of HPV status. The main aim of primary tumour treatment is complete tumour eradication, which has to be balanced against optimal organ preservation without compromising oncological control. Early detection and treatment of lymph node (LN) metastasis is the main determinant of survival. Surgical LN staging with sentinel node biopsy is recommended for patients with a high-risk (≥pT1b) tumour with cN0 status. While (inguinal) LN dissection remains the standard for node-positive disease, multimodal treatment is needed in patients with advanced disease. Owing to a lack of controlled trials and large series, the levels of evidence and grades of recommendation are low in comparison to those for more common diseases.

CONCLUSIONS

This collaborative penile cancer guideline provides updated information on the diagnosis and treatment of penile cancer for use in clinical practice. Organ-preserving surgery should be offered for treatment of the primary tumour when feasible. Adequate and timely LN management remains a challenge, especially in advanced disease stages. Referral to centres of expertise is recommended.

PATIENT SUMMARY

Penile cancer is a rare disease that significantly impacts quality of life. While the disease can be cured in most cases without lymph node involvement, management of advanced disease remains challenging. Many unmet needs and unanswered questions remain, underlining the importance of research collaborations and centralisation of penile cancer services.

HPV-negative Penile Intraepithelial Neoplasia (PeIN) With Basaloid Features

Most human papillomavirus (HPV)-independent penile squamous cell carcinomas (PSCCs) originate from an intraepithelial precursor called differentiated penile intraepithelial neoplasia, characterized by atypia limited to the basal layer with marked superficial maturation. Previous studies in vulvar cancer, which has a similar dual etiopathogenesis, have shown that about one fifth of HPV-independent precursors are morphologically indistinguishable from high-grade squamous intraepithelial lesions (HSILs), the precursor of HPV-asssociated carcinomas. However, such lesions have not been described in PSCC. From 2000 to 2021, 55 surgical specimens of PSCC were identified. In all cases, thorough morphologic evaluation, HPV DNA detection, and p16, p53, and Ki-67 immunohistochemical (IHC) staining was performed. HPV-independent status was assigned based on both negative results for p16 IHC and HPV DNA. Thirty-six of the 55 PSCC (65%) were HPV-independent. An intraepithelial precursor was identified in 26/36 cases (72%). Five of them (19%) had basaloid features, morphologically indistinguishable from HPV-associated HSIL. The median age of the 5 patients was 74 years (range: 67 to 83 y). All 5 cases were p16 and DNA HPV-negative. Immunohistochemically, 3 cases showed an abnormal p53 pattern, and 2 showed wild-type p53 staining. The associated invasive carcinoma was basaloid in 4 cases and the usual (keratinizing) type in 1. In conclusion, a small proportion of HPV-independent PSCC may arise on adjacent intraepithelial lesions morphologically identical to HPV-associated HSIL. This unusual histologic pattern has not been previously characterized in detail in PSCC. p16 IHC is a valuable tool to identify these lesions and differentiate them from HPV-associated HSIL.

Surgical technique and outcomes following coronal-sparing glans resurfacing for benign and malignant penile lesions

The aim of this study is to describe the outcomes for a modified glans-resurfacing technique for benign and malignant penile conditions in which the uninvolved glans corona is preserved in order to maintain glans erogenous sensation. A total of 13 patients underwent coronal-sparing glans resurfacing (CSGR), with follow-up every 3 months for ≥2 years. Positive surgical margin and local recurrence (LR) rates were evaluated. Surgical complications and cosmetic outcomes were also recorded. Patients were asked to complete the International Index of Erectile Function-5 (IIEF-5) questionnaire starting 12 months after the surgery. The median (interquartile range [IQR]) age and follow-up periods were 63 (53-68) years and 29 (14-38) months, respectively. Eight patients were diagnosed with primary penile squamous cell carcinoma (SCC), three had refractory lichen sclerosus, and two had penile intraepithelial neoplasia (PeIN). No surgical complications were recorded. All patients had a complete graft take and reported satisfactory cosmetic results with preserved erogenous sensation. Two cancer patients developed LR which was managed with further penile preserving surgery. The median (IQR) postoperative IIEF-5 value was 20 (17-23). This modified coronal-sparing technique was suitable for glans lesions that spare the coronal ridge and coronal sulcus. Preservation of the coronal ridge helps maintain sexual function and provides excellent cosmetic outcomes.

Treatment Options and Outcomes for Men with Penile Intraepithelial Neoplasia: A Systematic Review

Penile intraepithelial neoplasia (PeIN) is a rare skin condition with potential to progress to invasive penile cancer. We performed a systematic review of treatment options and outcomes for PeIN. Topical agents showed response and recurrence rates of 40-100% and 20% for imiquimod, and 48-74% and 11% for 5-fluorouracil, respectively. Discontinuation of topical agents because of side effects was observed in 12% of cases. Response rates for laser therapies were 52-100%, with recurrence in 7-48% of cases and a change in penile sensitivity in 50%. Circumcision cleared preputial PeIN. Rates of recurrence after surgical treatment of glans PeIN were 25% for wide local excision, 4% for Mohs surgery, 5% for total glans resurfacing, and 10% for glansectomy. There are limited data on factors predictive of treatment response and on sequencing of treatment options. PATIENT SUMMARY: Several treatment options are available for men with precancerous lesions of the foreskin or glans. Close follow-up is necessary as lesions can recur or progress to invasive penile cancer.

[Penile carcinoma: Practical issues, from the biopsy to surgery]

The management of a penile carcinoma is complex, a collaboration between radiologist, pathologist and urologist is necessary to obtain a correct staging. In this review we try to demonstrate step by step how to achieve a complete pathology report, how to manage the patient (imaging, biopsy, fresh frozen section and surgery).

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.

Experimental Models for Studying HPV-Positive and HPV-Negative Penile Cancer: New Tools for An Old Disease

Simple Summary

Penile cancer is an uncommon and understudied malignancy that is most commonly diagnosed in developing countries. Therapeutic advances have been slow, in part due to the lack of in vitro and in vivo models for testing new drugs before performing clinical trials. Recently, this difficulty has been partly overcome and multiple new pre-clinical models were reported. These important developments will help develop new therapies for penile cancer patients. The present review summarizes and discusses the available data concerning the pre-clinical models of penile cancer and their uses. Comparisons are drawn between different models, allowing researchers to choose the most adequate setting for their experiments. The remaining gaps in this array of penile cancer models are also discussed, in particular the lack of models for studying metastatic disease and cell lines representing tumors associated with human papillomavirus.

Abstract

Penile cancer is an uncommon malignancy that occurs most frequently in developing countries. Two pathways for penile carcinogenesis are currently recognized: one driven by human papillomavirus (HPV) infection and another HPV-independent route, associated with chronic inflammation. Progress on the clinical management of this disease has been slow, partly due to the lack of preclinical models for translational research. However, exciting recent developments are changing this landscape, with new in vitro and in vivo models becoming available. These include mouse models for HPV⁺ and HPV⁻ penile cancer and multiple cell lines representing HPV⁻ lesions. The present review addresses these new advances, summarizing available models, comparing their characteristics and potential uses and discussing areas that require further improvement. Recent breakthroughs achieved using these models are also discussed, particularly those developments pertaining to HPV-driven cancer. Two key aspects that still require improvement are the establishment of cell lines that can represent HPV⁺ penile carcinomas and the development of mouse models to study metastatic disease. Overall, the growing array of in vitro and in vivo models for penile cancer provides new and useful tools for researchers in the field and is expected to accelerate pre-clinical research on this disease.