Incidence of penile cancer worldwide: systematic review and meta-analysis

Penile carcinoma: A retrospective analysis of 93 patients at a tertiary care center in Jakarta, Indonesia

OBJECTIVES

Penile carcinoma (PC) is a rare disease with considerable physical and psychological impact. To date, there is no data regarding PC prevalence and characteristics in Indonesia. This study aimed to analyze the characteristics of patients with PC in Indonesia and determine cumulative survival rates and time to disease progression.

METHODS

This was a retrospective study of all patients diagnosed with PC at Cipto Mangunkusumo General Hospital from 1995 to 2014, with a minimum of 1 year follow-up. The outcomes of the study were cumulative survival rates and time-to-disease progression.

RESULTS

Ninety-three subjects were recruited, with a mean age of 49.44 ± 13.62. Inguinal lymph node dissection (ILND) was performed in 49 (53%) patients. The mean survival in the ILND group was better compared to the non-ILND group (80.7 months vs. 67.1 months; p = 0.032). Time-to-progression in the ILND group was significantly longer than in the non-ILND group (71.7 months vs. 54.3 months; p = 0.022). No significant difference in survival between the total and partial penectomy (PP) groups was observed (p = 0.701). Time-to-progression in total penectomy (TP) was significantly longer than in PP (68 months vs. 56.0 months; p = 0.023). In Cox-regression analysis, after adjustment of other variables, history of ILND, higher stage of cancer, and older age were found to affect the survival of patients.

CONCLUSION

ILND in PC led to better survival and reduced disease progression. The type of penectomy is only associated with progression but not survival. TP had a longer time to disease progression compared to PP.

Comparative outcomes of partial versus total penectomy for penile carcinoma: A retrospective cohort study on demographics and postoperative complications

When feasible from an oncologic standpoint, partial penectomy (PP) is often preferred to total penectomy (TP) for penile cancer treatment, for the preservation of functional urinary outcomes. However, to date, there has not been a direct comparison of perioperative outcomes between PP and TP. Comparing treatments for penile cancer has proven difficult due to the rarity of penile cancer in the United States. We aimed to report differences in pre-operative risk factors, intra-operative outcomes, and postoperative outcomes between TP and PP for penile cancer. Using the National Surgical Quality Improvement Program database, we conducted a retrospective cohort review of penile cancer patients enlisted in the database between the years 2006-2016 using the International Classification of Diseases clinical modification 9th revision codes. A total of 260 patients, 67 TP and 193 PP patients, were included. PP patients were less likely to be transferred patients (p = 0.002), diabetic (p = 0.026), and were more likely to have preoperative laboratory values within normal limits. PP patients also had shorter lengths of stay in the hospital (p < 0.001) and operating time (p < 0.001). Significant differences were also found for inpatient stay (p < 0.001), 30-day post-surgery complications (p < 0.001), deep incisional surgical site infection (SSI) (p = 0.017), wound disruption (p = 0.017), intraoperative or postoperative transfusion (p = 0.029), and sepsis (p < 0.005). Finally, PP patients required fewer concurrent surgical procedures (p < 0.001). Demographic differences between PP and TP patients may reflect patients presenting with more advanced oncologic disease. PP is associated with fewer postoperative complications, shorter surgeries, shorter hospital stays, fewer concurrent surgical procedures, and comorbid conditions compared to TP. A gap remains in the reported data pertaining to postoperative sexual function and erectile outcomes for PP at a national level.

P53 Gene as a Promising Biomarker and Potential Target for the Early Diagnosis of Reproductive Cancers

One of the crucial aspects of cancer research is diagnosis with specificity and accuracy. Early cancer detection mostly helps make appropriate decisions regarding treatment and metastasis. The well-studied transcription factor tumor suppressor protein p53 is essential for maintaining genetic integrity. p53 is a key tumor suppressor that recognizes the carcinogenic biological pathways and eradicates them by apoptosis. A wide range of carcinomas, especially gynecological such as ovarian, cervical, and endometrial cancers, frequently undergo TP53 gene mutations. This study evaluates the potential of the p53 gene as a biological marker for the diagnosis of reproductive system neoplasms. Immunohistochemistry of p53 is rapid, easy to accomplish, cost-effective, and preferred by pathologists as a surrogate for the analysis of TP53 mutation. Thus, this review lays a groundwork for future efforts to develop techniques using p53 for the early diagnosis of cancer.

[Lymph node metastatic penile cancer: a challenge in uro-oncology-guideline-conform treatment]

Penile squamous cell carcinoma is a rare, highly aggressive cancer of older men. The metastatic stage has significant therapeutic and prognostic features. Treatment of penile cancer is significantly influenced by the operation, in which an R0 situation must be achieved to ensure a realistic chance of cure. Other local therapeutic procedures such as radiotherapy are often of secondary importance. Neoadjuvant and adjuvant chemotherapy are relevant components of multimodal therapy. Post-therapeutically, patients require lifelong, risk-adapted follow-up care.

Comprehensive genomic profiling of penile squamous cell carcinoma and the impact of human papillomavirus status on immune-checkpoint inhibitor-related biomarkers

BACKGROUND

Advanced penile squamous cell carcinoma (pSCC) is a rare and aggressive malignancy with limited success of immune-checkpoint inhibitors (ICIs). Approximately half of pSCC cases are associated with human papillomavirus (HPV) infection.

METHODS

Evaluation was done retrospectively of the landscape of somatic alterations and ICI-related biomarkers in pSCC by using the Caris Life Sciences data set with the aim to establish signatures for HPV-dependent oncogenesis. The pSCC tumors were analyzed by using next-generation sequencing (NGS) of DNA and RNA. Programmed death ligand 1 (PD-L1) expression was evaluated by immunohistochemistry (IHC). Microsatellite instability (MSI) was tested by fragment analysis, IHC (SP142; ≥1%), and NGS. Tumor mutational burden (TMB)-high was defined as ≥10 mutations/Mb. HPV16/18 status was determined by using whole-exome sequencing (WES) when available. Significance was adjusted for multiple comparisons (q value < .05).

RESULTS

NGS of the overall cohort (N = 108) revealed TP53 (46%), CDKN2A (26%), and PIK3CA (25%) to be the most common mutations. Overall, 51% of tumors were PD-L1+, 10.7% had high TMB, and 1.1% had mismatch repair-deficient (dMMR)/MSI-high status. Twenty-nine patients had their HPV status made available by WES (HPV16/18+, n = 13; HPV16/18-, n = 16). KMT2C mutations (33% vs. 0%) and FGF3 amplifications (30.8% vs. 0%) were specific to HPV16/18+ tumors, whereas CDKN2A mutations (0% vs. 37.5%) were exclusive to HPV16/18- tumors. TMB-high was exclusively found in the HPV16/18+ group (30.8%). The two groups had comparable PD-L1 and dMMR/MSI-H status.

CONCLUSIONS

In a large and comprehensive NGS-based evaluation of somatic alterations in pSCC, HPV16/18+ versus HPV16/18- pSCCs were molecularly distinct tumors. Our finding that TMB-high is exclusive to HPV16/18+ tumors requires confirmation in larger data sets.

PLAIN LANGUAGE SUMMARY

Penile squamous cell carcinoma (pSCC) is a rare and aggressive malignancy in the advanced setting, with poor prognosis and little success with immune-checkpoint inhibitors (ICIs) in an unselected patient approach. Human papillomavirus (HPV) infection is a known risk factor for pSCC; its impact on genomic tumor profiling is less defined. Using next-generation sequencing, we explored the genetic landscape and ICI-related biomarkers of pSCC and HPV-driven oncogenic molecular signatures. Our results indicate that HPV-positive and HPV-negative pSCCs are molecularly distinct tumors. Increased tumor mutational burden is associated with HPV-positive tumors, and could serve as a biomarker for predicting therapeutic response to ICI-based therapies. Our results support the growing literature indicating that HPV status in pSCC can be used to guide patient stratification in ICI-based clinical trials.

Development and validation of a predictive model for penile cancer based on the surveillance, epidemiology, and end results database and multi-center cases

PURPOSE

Penile cancer (PC) is a great impact on the quality of life and psychological status of patients. This study aimed to construct nomograms using data from the Surveillance, Epidemiology, and End Results (SEER) database to predict overall survival (OS) and cancer-specific survival (CSS) in patients with penile cancer (PC).

METHODS

Patients were divided into a training cohort (n = 634) and a validation cohort (n = 272) in a 7:3 ratio. Independent risk factors influencing the prognosis of PC were screened using univariate and multivariate Cox analyses, and models for predicting PC were developed. Data from 203 patients with PC in four tertiary hospitals in Gansu Province from 2012 to 2021 were externally validated.

RESULTS

Univariate analysis and multivariate analysis showed revealed that the OS-related factors were age, grade, T stage, N stage, M stage and tumor size (p < 0.05); the CSS-related factors were age, mode of surgery, T stage, N stage, M stage and tumor size (p < 0.05). The C-indices of the OS and CSS nomograms in the training cohort were 0.743 [95% confidence interval (CI) (0.714-0.772)] and 0.797 (0.762-0.832), respectively. The C-indices of the OS and CSS nomograms in the internal validation cohort were 0.735 (0.686-0.784) and 0.755 (0.688-0.822), respectively, and those in the external validation cohort were 0.801 (0.746-0.856) and 0.863 (0.812-0.914), respectively. Receiver operating characteristic (ROC) curves, calibration curves, and survival curves all demonstrated good predictive performance of the nomograms.

CONCLUSION

The nomograms for PC were developed using the SEER database. The accuracy and clinical usefulness of the model were validated through a combination of internal and external validations.

Regional differences in penile cancer patient characteristics and treatment rates across the United States

INTRODUCTION

We tested for regional-specific differences in patient, tumor and treatment characteristics as well as cancer-specific mortality (CSM) of squamous cell carcinoma of the penis (SCCP) patients, across the Surveillance, Epidemiology, and End Results (SEER) registries.

METHODS

The SEER database (2000-2018) was used to tabulate patient (age at diagnosis, race/ethnicity), tumor (stage, grade, N-stage) and treatment characteristics (proportions of primary tumor surgery, local lymph node surgery, systemic therapy), according to 12 SEER registries. Multinomial regression models, as well as multivariable Cox regression models tested for CSM differences, adjusting for patient, tumor and treatment characteristics.

RESULTS

In 5395 SCCP patients, registry-specific patient counts ranged from 2060 (38 %) to 64 (1 %). Differences across registries existed for race/ethnicity, stage, grade and N-stage. Additionally, in stage I-II SCCP patients, proportions of local tumor destruction (LTD) ranged from 19 % to 39 % and from 33 % to 61 % for partial penectomy. In stage III-IV SCCP patients, proportions of partial penectomy ranged from 40 % to 59 % and from 17 % to 50 % for radical penectomy. Local lymph node surgery ranged from 8 % to 24 % and proportions of systemic therapy ranged from 3 % to 14 %. Significant inter-registry differences remained, after adjustment for treatment proportions. Unadjusted five-year CSM ranged from 19 % to 32 %. In multivariable analyses, one registry exhibited significantly higher CSM (SEER registry 10, Hazard Ratio [HR] 1.48), relative to the largest reference registry (SEER registry 1, n = 2060).

CONCLUSION

Important regional differences including patient, tumor and treatment characteristics exist for SCCP patients across SEER registries. After multivariable adjustment, no differences in CSM were recorded, with the exception of one registry.

Inguinal lymphadenectomy in penile cancer patients: a comparison between open and video endoscopic approach in a multicenter setting

OBJECTIVES

To compare differences of operative outcomes, post-operative complications and survival outcomes between open and laparoscopic cases in a multicenter study.

METHODS

This was a retrospective cohort study performed at three European centers from September 2011 to January 2019. The surgeon decision to perform open inguinal lymphadenectomy (OIL) or video endoscopic inguinal lymphadenectomy (VEIL) was done in each hospital after patient counselling. Inclusion criteria regarded a minimum follow-up of 9 months since the inguinal lymphadenectomy.

RESULTS

A total of 55 patients with proven squamous cell penile cancer underwent inguinal lymphadenectomy. 26 of them underwent OIL, while 29 patients underwent VEIL. For the OIL and VEIL groups, the mean operative time was 2.5 vs. 3.4 h (p=0.129), respectively. Hospital stays were lower in the VEIL group with 4 vs. 8 days in OIL patients (p=0.053) while number of days requiring drains to remain in situ was 3 vs. 6 days (p=0.024). The VEIL group reported a lower incidence of major complications compared to the OIL group (2 vs. 17%, p=0.0067) while minor complications were comparable in both groups. In a median follow-up period of 60 months, the overall survival was 65.5 and 84.6% in OIL and VEIL groups, respectively (p=0.105).

CONCLUSIONS

VEIL is comparable to OIL regarding safety, overall survival and post-operative outcomes.

Prognostic Markers and Trials in Penile Cancer

New tumor biomarkers open the potential for designing personalized therapy for penile squamous cell carcinoma. Despite the initial promising results of some biomarkers, controversy remains due to contradictory studies. Further robust research work is required before incorporating biomarkers in the personalized management of penile cancer. This narrative review aims to highlight some of the most commonly and recently investigated biomarkers of penile cancer and to summarize the ongoing registered clinical trials for the management of penile cancer patients.

Evaluation of Health-Related Quality of Life in Patients Receiving Treatment for Penile Cancer: A Single-Center Cross- Sectional Study

INTRODUCTION

Penile cancer is one of the uncommon types of cancer in men. The treatment could significantly impact a patient's quality of life (QOL), leading to difficulties in fulfilling life functions.

METHODS

This descriptive observational study aimed to describe a situation using a cross-sectional design objectively. The population of this study was all patients with a diagnosis of penile cancer who underwent therapy at the Haji Adam Malik Hospital from September 2020 to September 2021. Quality of life was assessed using EORTC QLQ-C30.

RESULTS

The respondents' mean age and standard deviation were 54.44 and 8.647 years, respectively. The youngest was 38 years, while the oldest age was 64 years. Most respondents had no history of circumcision (55.6%). All respondents had a poor QOL based on the 28 components in the questionnaire. This study showed that erectile function, changes in sexual function, and overall sexual function were correlated with health-related quality of life (HRQoL) post-treatment. In general, lack of sexual activity is the primary factor responsible for decreasing HRQoL in penile cancer patients. It has been reported that 70% of patients experienced a negative impact on sexuality post-treatment.

CONCLUSION

The quality of life in patients receiving treatment for penile cancer at RSUP H. Adam Malik, Medan, was poor. It is associated with a lack of sexual activity.

WHO 2022 classification of penile and scrotal cancers: updates and evolution

Squamous cell carcinoma (SCC) is the most common malignant tumour of the penis. The 2022 WHO classification reinforces the 2016 classification and subclassifies precursor lesions and tumours into human papillomavirus (HPV)-associated and HPV-independent types. HPV-associated penile intraepithelial neoplasia (PeIN) is a precursor lesion of invasive HPV- associated SCC, whereas differentiated PeIN is a precursor lesion of HPV-independent SCC. Block-type positivity of p16 immunohistochemistry is the most practical daily utilised method to separate HPVassociated from HPVindependent penile SCC. If this is not feasible, the term SCC, not otherwise specified (NOS) is appropriate. Certain histologies that were previously classified as "subtypes" are now grouped, and coalesced as "patterns", under the rubric of usual type SCC and verrucous carcinoma (e.g. usual-type SCC includes pseudohyperplastic and acantholytic/pseudoglandular carcinoma, and carcinoma cuniculatum is included as a pattern of verrucous carcinoma). If there is an additional component of the usual type of invasive SCC (formerly termed hybrid histology), the tumour would be a mixed carcinoma (e.g. carcinoma cuniculatum or verrucous carcinoma with usual invasive SCC); in such cases, reporting of the relative percentages in mixed tumours may be useful. The consistent use of uniform nomenclature and reporting of percentages will inform the refinement of future reporting classification schemes and guidelines/recommendations. The classification of scrotal tumours is provided for the first time in the fifth edition of the WHO Blue book, and it follows the schema of penile cancer classification for both precursor lesions and the common SCC of the scrotum. Basal cell carcinoma of the scrotum may have a variable clinical course and finds a separate mention.

Incidence, mortality and survival trends of penile cancer in Lithuania 1998-2017

Background and objectives

The aim of this study was to analyse trends in penile cancer incidence, mortality, and relative survival in Lithuania during the period of 1998-2017.

Materials and methods

The study was based on all cases of penile cancer reported to the Lithuanian Cancer Registry between 1998 and 2017. Age-specific rates standardized rates were calculated, using the direct method (World standard population). The Joinpoint regression model was used to provide estimated average annual percentage change (AAPC). One-year and five-year relative survival estimates were calculated using period analysis. Relative survival was calculated as the ratio of the observed survival of cancer patients and the expected survival of the underlying general population.

Results

During the study period, the age-standardized incidence rate of penile cancer varied between 0.72 and 1.64 per 100 000, with AAPC 0.9% (95% CI -0.8-2.7). The mortality rate of penile cancer in Lithuania during this period varied from 0.18 to 0.69 per 100 000, with AAPC of -2.6% (95% CI -5.3-0.3). Relative one-year survival of patients, diagnosed with penile cancer improved over the time from 75.84% in period 1998-2001 to 89.33% in period 2014-2017. Relative five-year survival rate of patients, diagnosed with penile cancer changed from 55.44% in period 1998-2001 to 72.90% in period 2014-2017.

Conclusions

The incidence rates of penile cancer showed an increasing trend, while mortality rates were decreasing in Lithuania during 1998-2017. One-year and five-year relative survival increased, however, it does not reach the highest scores of Northern European countries.

HPV infection and 5mC/5hmC epigenetic markers in penile squamous cell carcinoma: new insights into prognostics

BACKGROUND

Penile cancer is one of the most aggressive male tumors. Although it is preventable, the main etiologic causes are lifestyle behaviors and viral infection, such as human papillomavirus (HPV). Long-term epigenetic changes due to environmental factors change cell fate and promote carcinogenesis, being an important marker of prognosis. We evaluated epidemiological aspects of penile squamous cell carcinoma (SCC) and the prevalence of HPV infection using high-risk HPV (hrHPV) and p16^INK4A expression of 224 participants. Global DNA methylation was evaluated through 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC).

RESULTS

The incidence of HPV was 53.2% for hrHPV and 22.32% for p16^INK4a. hrHPV was not related to systemic or lymph node metastasis and locoregional recurrence, nor influenced the survival rate. P16^INK4a seems to be a protective factor for death, which does not affect metastasis or tumor recurrence. Lymph node and systemic metastases and locoregional recurrence increase the risk of death. An increased 5mC mark was observed in penile SCC regardless of HPV infection. However, there is a reduction of the 5hmC mark for p16^INK4a + (P = 0.024). Increased 5mC/5hmC ratio (> 1) was observed in 94.2% of penile SCC, irrespective of HPV infection. Despite the increase in 5mC, it seems not to affect the survival rate (HR = 1.06; 95% CI 0.33-3.38).

CONCLUSIONS

P16^INK4a seems to be a good prognosis marker for penile SCC and the increase in 5mC, an epigenetic mark of genomic stability, may support tumor progression leading to poor prognosis.

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.

A single-center comparison of our initial experiences in treating penile and urethral cancer with video-endoscopic inguinal lymphadenectomy (VEIL) and later experiences in melanoma cases

Background

Video-endoscopic inguinal lymphadenectomy (VEIL) is a minimally invasive approach that is increasingly indicated in oncological settings, with mounting evidence for its long-term oncological safety.

Objectives

To present our single-center experience of treating penile and urethral cancer with VEIL, as well as its more recent application in melanoma patients.

Methods

We prospectively recorded our experiences with VEIL from September 2010 to July 2018, registering the patient primary indication, surgical details, complications, and follow-up.

Results

Twenty-nine patients were operated in one (24) or both (5) groins; 18 had penile cancer, 1 had urethral cancer, and 10 had melanoma. A mean 8.62 ± 4.45 lymph nodes were removed using VEIL and of these, an average of 1.00 ± 2.87 were metastatic; 16 patients developed lymphocele and 10 presented some degree of lymphedema; there were no skin or other major complications. The median follow-up was 19.35 months; there were 3 penile cancer patient recurrences in the VEIL-operated side. None of the melanoma patients presented a lymphatic inguinal recurrence.

Conclusions

VEIL is a minimally invasive technique which appears to be oncologically safe showing fewer complications than open surgery. However, complications such as lymphorrhea, lymphocele, or lymphedema were not diminished by using VEIL.

Clinical and Novel Biomarkers in Penile Carcinoma: A Prospective Review

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

Prognostic utility of SOX2, STAT3, and CD44high/CD24low expression in penile cancer

PURPOSE

Penile cancer has a high incidence in developing countries. The standard treatment is removal of the primary tumor and, when necessary, inguinal lymphadenectomy. Currently, the most important prognostic factor is lymph node disease, however, the available staging methods are inaccurate, and the high morbidity rate of lymphadenectomy has stimulated the study of predictive biomarkers of lymph node metastasis for selecting the patients who need lymphadenectomy. SOX2, STAT3 and CD44^high/CD24^low were chosen because they have provided good predictive results in other squamous cell carcinoma (SCC), although there are no studies for penile cancer. Thus, the expression of SOX2, STAT3, CD24+, and CD44+ in the penile cancer tumor microenvironment was investigated for correlation with tumor behavior in SCC.

METHODS

This observational, prospective, translational study included 34 men and investigated the expression of SOX2, STAT3, CD24+, and CD44+ in tumor tissue by flow cytometry.

RESULTS

The median age of the 38 evaluated patients with penile cancer was 61 (37-80) years. Most patients presented a tumor located on the glans penis (82.3%), with the usual histological type (79.4%) and 61.7% of patients presented stage pT2. No metastasis was found in 85.3% of patients. The expression of SOX2, STAT3 and CD44^high/CD24^low in the microenvironment of penile SCC treated with lymphadenectomy was significantly associated with aggressive tumor behavior (p < 0.05). STAT3 expression shows discrepant points when evaluated in context of angiolymphatic vascular invasion.

CONCLUSION

SOX2, STAT3 and CD44^high/CD24^low in penile SCC can be indicators of prognosis, allowing for selection of more aggressive treatment when necessary.

Leiomyosarcoma of the Penis: A Case Report and Re-Appraisal

BACKGROUND

Penile leiomyosarcoma arises from smooth muscles, which can be from dartos fascia, erector pili in the skin covering the shaft, or from tunica media of the superficial vessels and cavernosa. We describe presentation, treatment options, and recurrence pattern of this rare malignancy.

CASE PRESENTATION

We present a case of penile leiomyosarcoma in a 70-year-old patient who presented to the urology clinic with 1-year history of a slowly enlarging penile mass associated with phimosis.

CONCLUSIONS

Prognosis of penile LMS is difficult to ascertain because reported cases are rare. Penile leiomyosarcoma can be classified as superficial or deep based on tumor relation to tunica albuginea. Deep tumors (> 3 cm), high-grade lesions, and tumors with involvement of corpora cavernosa, tend to spread locally and metastasize to distant areas and require more radical surgery with or without postoperative radiation therapy. In contrast, superficial lesions can be treated with local excision only.

Radioisotope-Guided Sentinel Lymph Node Biopsy in Penile Cancer: A Long-Term Follow-Up Study

Lymph node (LN) management is critical for survival in patients with penile cancer. However, radical inguinal lymphadenectomy carries a high risk of postoperative complications such as lymphedema, lymphocele, wound infection, and skin necrosis. The European Association of Urology guidelines therefore recommend invasive LN staging by modified inguinal lymphadenectomy or dynamic sentinel node biopsy (DSNB) in clinically node-negative patients (cN0) with intermediate- and high-risk tumors (≥ T1G2). However, the timing of DSNB (simultaneous vs. subsequent to partial or total penile resection) is controversial and the low incidence of penile cancer means that data on the long-term outcomes of DSNB are limited. The present study aimed to analyze the reliability and morbidity of DSNB in patients with penile cancer during long-term follow-up. This retrospective study included 41 patients (76 groins) who underwent radioisotope-guided DSNB simultaneously or secondarily after penile surgery from June 2004 to November 2018. In total, 193 sentinel LNs (SLNs) and 39 non-SLNs were removed. The median number of dissected LNs was 2.5 (interquartile range 2–4). Histopathological analysis showed that five of the 76 groins (6.6%) contained metastases. None of the non-SLNs were tumor-positive. In accordance with the guidelines, all inguinal regions with positive SLNs underwent secondary radical inguinal lymphadenectomy, which revealed three additional metastases in one groin. Regional LN recurrence was detected in three patients (four groins) during a median follow-up of 70 months, including two patients in whom DSNB had been performed secondarily after repetitive penile tumor resections. DSNB-related complications occurred in 15.8% of groins. Most complications were mild (Clavien–Dindo grade I; 50%) or moderate (II; 25%), and invasive intervention was only required in 3.9% of groins (IIIa: n = 1; IIIb: n = 2). In summary, this study suggests that the current radioisotope-guided DSNB procedure may reduce the complication rate of inguinal lymphadenectomy in patients with cN0 penile cancer. However, DSNB and penile surgery should be performed simultaneously to minimize the false-negative rate. Recent advances, such as new tracers and imaging techniques, may help to reduce the false-negative rate of DSNB further.

Analysis of quality information provided by "Dr. YouTubeTM" on Phimosis

The objective of the current study was to evaluate the quality of the information provided in YouTube^TM videos on phimosis. The term “phimosis” was searched on YouTube^TM, and the Patient Education Materials Assessment Tool (PEMAT) for Audio/Visual Materials (Understandability and Actionability sections, good-quality score of minimum 70%) and misinformation scale (rated from 1 to 5) were used to assess video quality. Quality assessment was investigated over time. Of all, 60 were eligible for analysis. Healthcare providers were the authors of 75.0% of the videos, and 73.3% of the videos were patient-targeted. The median Understandability score was 42.9% (interquartile range [IQR]:34.5–58.9) and ranged from 28.6 to 42.9% (2013–2020). The median Actionability score was 50.0% (IQR:25.0–56.2) and ranged from 25.0 to 50.0% (2013–2020). The median misinformation score was 2.8/5 (IQR:1.6–3.6), and although the score fluctuated over time, the median score was 2.6 both in 2013 and in 2020. According to our results, although an increase of PEMAT over time was observed, the overall quality of the information uploaded on YouTube^TM is low. Therefore, at present, YouTube^TM cannot be recommended as a reliable source of information on phimosis. Video producers should upload higher-quality videos to help physicians and patients in the decision-making process.

Minimal invasive approaches in lymph node management of carcinoma of penis: A review

INTRODUCTION

Inguinal lymph node dissection (ILND) is an integral part in the management of carcinoma penis. The concerns about the postoperative morbidity associated with open ILND led to modification in the template of dissection and adoption of minimally invasive techniques such as video endoscopic inguinal lymphadenectomy (VEIL) and robotic-assisted VEIL (R-VEIL). In this review, we aim to describe the techniques, case selection, perioperative outcomes, and oncological outcomes of VEIL and R-VEIL and to compare it with open ILND.

METHODS

Databases of PubMed, Embase, and Google Scholar were searched to identify the articles for VEIL and R-VEIL. Using PRISMA guidelines, literature search yielded 3783 articles, of which 32 full-text articles relevant to the topic were selected and reviewed, after consensus from authors.

RESULTS

After the first description of VEIL, various modifications in port placements and approaches were described. Several studies have shown, VEIL and R VEIL are safe and feasible in both node-negative and node-positive Ca penis patients. Compared to open ILND, VEIL had fewer wound infections and skin necrosis, minimal blood loss, shorter mean hospital stays, and reduced duration of drain kept. There is no difference in mean lymph node yield and recurrence rates between open ILND, VEIL, R-VEIL.

CONCLUSION

VEIL and R-VEIL are safe and have comparable oncological outcomes with open ILND.

Association of human papillomavirus in penile cancer: A single-center analysis

Introduction

Human papillomavirus (HPV) is a known risk factor of penile cancer (PeCa). However, studies evaluating its true association are limited. In this study, we aimed to estimate HPV prevalence and its true association with PeCa in terms of molecular biological activities.

Materials and Methods

This single-institutional prospective observational study was conducted between June 2016 and August 2019. We included 40 men with PeCa as a study group and 20 age-matched uncircumcised men who underwent circumcision for phimosis as a control group. Both the groups underwent deoxyribonucleic acid isolation for HPV subtyping followed by evaluation of relative E6/E7 messenger ribonucleic acid (mRNA) expression profile and relative telomerase activity in tissue samples. HPV-16 and -18 were categorized as high-risk, whereas HPV-6 and -11 were categorized as low-risk subtypes.

Results

The mean (±standard deviation) age of PeCa was 51 ± 15.9 years. The majority of patients had stage II disease, and the most common procedure done was partial penectomy. The overall prevalence of HPV in PeCa was 42.5% (n = 17) as compared to 20% (n = 4) in controls. Among the subtypes, the most common subtype was HPV-16 noted in 33.3% (8/24) of cases, followed by HPV-18 in 29.2% (7/24) of cases. PeCa tissues had a significantly higher relative E7 mRNA expression for HPV-18 than the control group (P = 0.016). The mean relative telomerase activity was significantly higher in the PeCa tissues than the control group (138.66 vs. 14.46, P < 0.001). A significantly higher relative telomerase activity was noted in the PeCa tissues positive for high-risk HPV subtypes than controls (141.90 vs. 14.46, P = 0.0008), but not between high-risk HPV-positive and HPV-negative PeCa cases (141.90 vs. 137.03, P = 0.79). High-risk subtypes were not associated with tumor stage (P = 0.76) or lymph node metastasis (P = 0.816).

Conclusions

HPV was associated in 42.5% of PeCa cases based on our experience from a single institution. PeCa tissues had a higher relative E7 mRNA expression for HPV-18 and relative telomerase activity as compared to controls suggesting their potential role as surrogate markers of virus-induced tumorigenesis.

Pathogenesis of Penile Squamous Cell Carcinoma: Molecular Update and Systematic Review

Penile squamous cell carcinoma (PSCC) is a rare but aggressive neoplasm with dual pathogenesis (human papillomavirus (HPV)-associated and HPV-independent). The development of targeted treatment is hindered by poor knowledge of the molecular landscape of PSCC. We performed a thorough review of genetic alterations of PSCC focused on somatic mutations and/or copy number alterations. A total of seven articles have been identified which, overall, include 268 PSCC. However, the series are heterogeneous regarding methodologies employed for DNA sequencing and HPV detection together with HPV prevalence, and include, in general, a limited number of cases, which results in markedly different findings. Reported top-ranked mutations involve TP53, CDKN2A, FAT1, NOTCH-1 and PIK3CA. Numerical alterations involve gains in MYC and EGFR, as well as amplifications in HPV integration loci. A few genes including TP53, CDKN2A, PIK3CA and CCND1 harbor both somatic mutations and copy number alterations. Notch, RTK-RAS and Hippo pathways are frequently deregulated. Nevertheless, the relevance of the identified alterations, their role in signaling pathways or their association with HPV status remain elusive. Combined targeting of different pathways might represent a valid therapeutic approach in PSCC. This work calls for large-scale sequencing studies with robust HPV testing to improve the genomic understanding of PSCC.

Low level of interobserver concordance in assessing histological subtype and tumor grade in patients with penile cancer may impair patient care

Differentiation between penile squamous cell carcinoma patients who can benefit from limited organ-sparing surgery and those at significant risk of lymph node metastasis is based on histopathological prognostic factors including histological grade and tumor histological subtype. We examined levels of interobserver and intraobserver agreement in assessment of histological subtype and grade in 207 patients with penile squamous cell carcinoma. The cases were assessed by seven pathologists from three hospitals located in Sweden and Italy. There was poor to moderate concordance in assessing both histological subtype and grade, with Fleiss kappas of 0.25 (range: 0.02-0.48) and 0.23 (range: 0.07-0.55), respectively. When choosing HPV-associated and non-HPV-associated subtypes, interobserver concordance ranged from poor to good, with a Fleiss kappa value of 0.36 (range: 0.02-0.79). A re-review of the slides by two of the pathologists showed very good intraobserver concordance in assessing histological grade and subtype, with Cohen's kappa values of 0.94 and 0.91 for grade and 0.95 and 0.84 for subtype. Low interobserver concordance could lead to undertreatment and overtreatment of many patients with penile cancer, and brings into question the utility of tumor histological subtype and tumor grade in determining patient treatment in pT1 tumors.

Rahim MA, Sidek Ahmad ZNB. Impact of Social Distancing on COVID-19 and Other Related Infectious Disease Transmission: A Systematic Review

Background   Similar to other coronaviruses, COVID-19 is transmitted mainly by droplets and is highly transmissible through close proximity or physical contact with an infected person. Countries across the globe have implemented public health control measures to prevent onwards transmission and reduce burden on health care settings. Social or physical distancing was found to be one of appropriate measure based on previous experience with epidemic and pandemic contagious diseases. This study aims to review the latest evidence of the impact of social or physical distancing implemented during COVID-19 pandemic towards COVID-19 and other related infectious disease transmission.   Methodology   The study uses PRISMA review protocol and formulation of research question was based on PICO. The selected databases include Ovid MEDLINE and Scopus. Thorough identification, screening and eligibility process were done, revealed selected 8 articles. The articles then ranked in quality through MMAT.   Results   A total of eight papers included in this analysis. Five studies (USA, Canada, South Korea and the United Kingdom) showed physical distancing had resulted in a reduction in Covid-19 transmission. In comparison, three other studies (Australia, South Korea and Finland) showed a similar decline on other infectious diseases (Human Immunodeficiency Virus (HIV), other sexually transmitted infections (STI), Influenza, Respiratory Syncytial Virus (RSV) and Vaccine-Preventive Disease (VPD). The degree of the distancing policy implemented differ between strict and lenient, with both result in effectiveness in reducing transmission of infectious disease.   Conclusion   Physical or social distancing may come in the form of extreme or lenient measure in effectively containing contagious disease like COVID-19, however the stricter the measure will give more proportionate impact towards the economy, education, mental health issues, morbidity and mortality of non-COVID-19 diseases. Since we need this measure to ensure the reduction of infectious diseases transmission in order to help flattening the curve which allow much needed time for healthcare system to prepare adequately to response, ‘Precision physical distancing” can be implemented which will have more benefit towards the survival of the community as a whole.

The Burden of Penile Cancer in Bali Compared to Other Provinces in Indonesia

Objective: In Indonesia, 45% of the total penile cancer cases are concentrated in Bali province, where penile cancer is ranked as the most common cancer during 2013. However, the incidences of penile cancer in Bali and other provinces in Indonesia are still unknown. The purpose of this study is to determine the age-standardized incidence rate (ASR), age-specific incidence rate (AR), and crude rate incidence (CRI) of penile cancer in Bali and other provinces in Indonesia. Methods: The data were obtained from 11 provinces in Indonesia over a period of 10 years (2004-2013). The samples were 1032 new cases of penile cancer collected manually from the registry. ASR, AR, and CRI were calculated based on the number of new penile cancer cases per 100,000 men in a given province. Indonesian population standard was used to calculate the age-standardized incidence rate. Result: There were variations on ASR, AR, and CRI for penile cancer in Indonesia. We found that the average CRI in Indonesia is 0.1 per 100,000 men. The incidence is found to be higher in Bali compared to other provinces. The average ASR in Bali is 2.1 per 100,000 men, CRI is 2.5 per 100,000 men, and the peak of AR being 12.9 per 100,000 men in the age group of 55-64 years old. The incidence of penile cancer is found to increase with age. In Bali, the peak incidence is in the 6th and 7th decades of life. The ASR and CRI of penile cancer in other provinces were less than 1 per 100,000 males. Conclusion:  The highest incidence of penile cancer is found in the Bali province compared to other provinces in Indonesia. This problem requires more serious attention and further research to identify the risk factors.  

The use of preoperative neutrophil-lymphocyte ratio and lymphocyte-monocyte ratio in predicting survival and groin node involvement of patients with squamous cell carcinoma of penis

Introduction:

The association between inflammation and malignancies is being recognized. In this study, we assessed the use of preoperative neutrophil–lymphocyte ratio (NLR) and lymphocyte–monocyte ratio (LMR) in predicting cancer-specific survival (CSS) and inguinal node involvement in patients with carcinoma penis.

Methods:

Sixty-nine patients operated for squamous cell carcinoma penis with inguinal node dissection between 2012 and 2020 were identified. We recorded the type of surgery (partial/total penectomy), T stage, grade, lymphovascular invasion (LVI), perineural invasion (PNI), pathological status of inguinal nodes and nodal stage (pN1–3), extranodal extension (ENE), and CSS. The hemogram performed within 2 weeks of surgery was used for calculating NLR and LMR.

Results:

Partial penectomy was the most common surgery (65.22%) and pT2 was the most common stage (53.62%). Grade 2 was seen in 66.67%, LVI in 34.78%, PNI in 37.68%, 52.17% had inguinal node involvement with pN3 being the most common (36.23%), and 36.23% had ENE. Kaplan–Meier analysis revealed that NLR of >3 and the LMR ≤3 indicated an inferior CSS (P = 0.05 and 0.04, respectively). T stage, inguinal node involvement, LVI, pN stage, and ENE were also associated with inferior CSS (P < 0.05). On multivariate analysis, T stage was significantly associated with CSS (P = 0.02). The NLR >3 and LMR ≤3 were also significantly associated with the presence of pathological inguinal node involvement (P = 0.001 and 0.026).

Conclusion:

NLR and LMR may help in predicting CSS and inguinal node involvement in patients of carcinoma penis.

Indigenous Groin Board Immobilization Reduces Planning Target Volume Margins in Groin Radiotherapy

Purpose:

To quantify the relative motion of pelvic and groin lymph nodes (PLN and GLN) and define indicative margins for image-guided radiotherapy based on bony anatomy for the frog-leg position (FLP) and groin immobilization board (GIB).

Materials and Methods:

Twenty patients with planning computed tomography (CT) scan and on treatment cone beam CTs (median = 8) for groin and pelvic radiotherapy were included in the study. Of these nine were treated with FLP and eleven with GIB. The PLN and GLN regions on the left and right were outlined in each scan. Systematic and random uncertainties were determined along with correlations between the motions of these regions. The clinical target volume to planning target volume (PTV) margins required to take motion into account was calculated for each immobilization.

Results:

The mean shifts for PLN and GLN were lesser but not statistically lower using GIB over FLP. There was significant concordance in the vertical, longitudinal and lateral motion of the pelvis and right groin (P = 0.015, 0.09 and 0.049, respectively), pelvis and left groin (P = 0.001, 0.048, and 0.006, respectively) and between left and right groin (P = 0.013, 0.01 and 0.07, respectively) for FLP and not GIB. The PTV margins required by Van Herk and Stroom's formula were reduced from 11 mm and 9 mm to 6 mm and 5 mm for pelvis; 12 mm and 11 mm to 7 mm and 6 mm for groin, respectively, using FLP over GIB.

Conclusions:

GIB brings concordance in shifts between pelvis and groin and between bilateral groins, thereby reducing the required PTV margins.

Real World Data of Penile Cancer Treatment at a High-Volume Center in South America: Insights and Survival Trends

OBJECTIVE

To report survival trends and oncological outcomes of penile cancer surgically treated patients, at a high-volume center, treating more than 25 patients each year, in a high incidence country.

METHODS

Clinical charts of all patients that underwent surgical management for penile cancer were reviewed. The primary end points were cancer specific survival (CSS), progression-free survival, and local recurrence free survival. Kaplan-Meier plots were used for survival analyses. Multivariate analysis was performed using cox proportional hazard age-adjusted models to determine the effect of pN, pT, lymphovascular invasion for CSS.

RESULTS

A total of 209 patients were identified, with a median follow up of 96 months (IQR 49-133). Organ-sparing surgerywas performed in 72.7%, 56.9% underwent dynamic sentinel lymph node biopsy, 110 patients underwent inguinal lymph node dissection, and 45 (21.5%) pelvic lymph node dissection. A total of 75 (35.8%) of patients relapsed, median time to relapse of 12 months (IQR 6-25). Overall estimates of CSS showed an 8-year CSS of 68.9%. Eight-year CSS was 90.5% for N0, and 32.8% in pN3 (P <.001). The Cox proportional hazard model showed that pN1-3, pT2-4, lymphovascular invasion and positive dynamic sentinel lymph node biopsy were the variables associated with worse 8-year CSS.

CONCLUSION

To the best of our knowledge, we report one of the largest cohorts on the survival outcomes of penile cancer surgical treatment, in a single institution, over a long period of time, were most patients are referred with high-risk, locally advanced or nodal disease.

Correlation Between the Evolution of Somatic Alterations During Lymphatic Metastasis and Clinical Outcome in Penile Squamous Cell Carcinoma

Penile squamous cell carcinoma (PSCC) is a rare malignancy with poor survival after standard treatment. Although genomic alterations of PSCC have been characterized in several latest studies, the association between the formation of somatic landscape and regional lymph node metastasis (LNM), an important predictor for patient survival, has not been comprehensively investigated. Here, we collected formalin-fixed paraffin-embedded tumor tissue and matched normal samples of 32 PSCC patients, including 14 LNM patients and 18 clinically node-negative patients, to implement a whole-exome sequencing. Comparison of genomic features among different lymph node status subgroups was conducted after genomic profiling and its effects on patient survival were explored. Top-ranked recurrent gene mutants in our PSCC cohort were TP53 (13/32), NOTCH1 (12/32), CDKN2A (11/32), TTN (9/32) and FAT1 (8/32), mainly identified in the Notch, Hippo, cell cycle, TP53, RTK-RAS and PI3K pathways. While CDKN2A was confirmed to be the driver gene in all PSCC patients, certain gene mutants were significantly enriched in LNM involved patients, including TP53 (9/14 vs. 4/18, p = 0.029) and GBF1 (4/14 vs. 0/18, p = 0.028). Overall survival stratification of PSCC patients were found to be significantly correlated with mutations of three genes, including PIK3CA (Hazard ratio [HR] = 4.15, p = 0.029), CHD7 (HR = 4.82, p = 0.032) and LAMC3 (HR = 15.9, p < 0.001). PIK3CA and LAMC3 held a higher prevalence in patients with LNM compared to those without LNM (PIK3CA: 3/14 vs. 1/18, LAMC3: 2/14 vs. 1/18). Our finding demonstrated that genomic divergence exists across PSCC patients with different lymph node statuses, and it may be correlated with their survival outcome. It helps delineate somatic evolution during tumor progression and perfect potential therapeutic intervention in this disease.

Case Report: Two Cases of Chemotherapy Refractory Metastatic Penile Squamous Cell Carcinoma With Extreme Durable Response to Pembrolizumab

Background

Penile squamous cell carcinoma (PSCC) is a rare malignancy, and those patients with metastatic disease have limited treatment options. Treatment is largely comprised of platinum-based chemotherapy; however, patients progressing after initial chemotherapy have a median overall survival (OS) of less than 6 months. Based on a high percentage of PD-L1 expression in patients with PSCC, and its biological similarities to other squamous cell carcinomas, we present two patient cases treated with pembrolizumab with extraordinary durable treatment response far beyond treatment with standard therapy.

Main Body

The first patient is a 64 year old male with PSCC who was treated with neoadjuvant chemotherapy, partial penectomy, and adjuvant radiation prior to developing metastatic disease. He had a high TMB (14 mutations/Mb) and was started on pembrolizumab with a complete response, which has been maintained for 38 months. The second patient is an 85 year old male with PSCC who was treated with partial penectomy and adjuvant chemotherapy and radiation prior to developing metastatic disease. He had positive PD-L1 expression CPS 130) and was started on pembrolizumab with a partial response, which has been maintained for 18 months after starting treatment.

Conclusions

These two cases of extreme durable response with pembrolizumab (with molecular data including TMB and PD-L1 status) represent a significant clinical benefit in this patient population. With limited treatment options that result in a median OS of less than 6 months, along with the toxicity profile of chemotherapy which may not be tolerated in elderly patients with comorbidities, this survival benefit with pembrolizumab, along with advances in tumor sequencing and clinical trials shows that there is a potentially significant benefit with novel therapies in this patient population.

Penile cancer: a Brazilian consensus statement for low- and middle-income countries

Purpose

Penile cancer is highly prevalent in low- and middle-income countries, with significant morbidity and mortality rates. The first Brazilian consensus provides support to improve penile cancer patients’ outcomes, based on expert’s opinion and evidence from medical literature.

Methods

Fifty-one Brazilian experts (clinical oncologists, radiation oncologists, urologists, and pathologists) assembled and voted 104 multiple-choice questions, confronted the results with the literature, and ranked the levels of evidence.

Results

Healthcare professionals need to deliver more effective communication about the risk factors for penile cancer. Staging and follow-up of patients include physical examination, computed tomography, and magnetic resonance imaging. Close monitoring is crucial, because most recurrences occur in the first 2–5 years. Lymph-node involvement is the most important predictive factor for survival, and management depends on the location (inguinal or pelvic) and the number of lymph nodes involved. Conservative treatment may be helpful in selected patients without compromising oncological outcomes; however, surgery yields the lowest rate of local recurrence.

Conclusion

This consensus provides an essential decision-making orientation regarding this challenging disease.

Electronic supplementary material

The online version of this article (10.1007/s00432-020-03417-1) contains supplementary material, which is available to authorized users.

Presence of HPV with overexpression of p16INK4a protein and EBV infection in penile cancer-A series of cases from Brazil Amazon

BACKGROUND

In Brazil, penile cancer (PC) is not uncommon. The highest incidence of PC is in the North and Northeast of the country. In addition to phimosis, the Human Papillomavirus (HPV) and Epstein-Baar Virus (EBV) infections are also related as risk factors for PC. The overexpression of p16INK4a is a surrogate sensitive marker of HPV infection in PC.

OBJECTIVES

To correlate p16INK4a overexpression and HPV infection status with EBV infection in a series of PC patients from the Amazon region.

METHODS

Tumor tissues from 47 PC cases were analyzed for the presence of HPV and EBV DNA by PCR. All PC patients were diagnosed between 2013 and 2018 at a public reference cancer center hospital in Manaus, Amazonas-Brazil. HPV was genotyped using E7 HPV16/HPV18 type-specific real-time PCR and the PapilloCheck® HPV-Screening assay. p16INK4a expression was evaluated by immunohistochemistry using the automated Ventana® BenchMark Ultra.

RESULTS

The mean age of patients at the time of diagnosis was 57.4 years ±SD 17.8 ranging from 20 to 90 years old. Most of the patients (64%) came from rural areas of the Amazonas State. Thirty patients had phimosis (64%). Among the patients with phimosis, 43% (13/30) underwent circumcision, three during childhood and 10 in adulthood. 60% of the patients were smokers or ex-smokers. HPV infection was observed in 45% (21/47) of cases. HPV16 was detected in 13 patients (61%). Other HPV types detected were HPV 6, 11, 42, 51, 53, 68 and 44/55. EBV infection was observed in 30% (14/47) of the patients with PC. Co-infection with HPV and EBV was observed in 28% (6/21) cases. p16INK4a was only investigated in 26 samples. The p16INK4a overexpression was observed exclusively in HPV 16 positive cases and four HPV negative cases. In the survival analysis, the follow-up time was 35.4 months/patient. The mortality rate during the follow up time was 38%.

CONCLUSIONS

p16INK4a positivity presented a high correlation to HPV 16 DNA detection, reinforcing its use as a surrogate marker for HPV-driven cancers. Infection with EBV was quite frequent and its role in epithelial penile oncogenesis needs to be demonstrated.

Substitution of Human Papillomavirus Type 16 L2 Neutralizing Epitopes Into L1 Surface Loops: The Effect on Virus-Like Particle Assembly and Immunogenicity

Cervical cancer caused by infection with human papillomaviruses (HPVs) is the fourth most common cancer in women globally, with the burden mainly in developing countries due to limited healthcare resources. Current vaccines based on virus-like particles (VLPs) assembled from recombinant expression of the immunodominant L1 protein are highly effective in the prevention of cervical infection; however, these vaccines are expensive and type-specific. Therefore, there is a need for more broadly protective and affordable vaccines. The HPV-16 L2 peptide sequences 108-120, 65-81, 56-81, and 17-36 are highly conserved across several HPV types and have been shown to elicit cross-neutralizing antibodies. To increase L2 immunogenicity, L1:L2 chimeric VLPs (cVLP) vaccine candidates were developed. The four L2 peptides mentioned above were substituted into the DE loop of HPV-16 L1 at position 131 (SAC) or in the C-terminal region at position 431 (SAE) to generate HPV-16-derived L1:L2 chimeras. All eight chimeras were transiently expressed in Nicotiana benthamiana via Agrobacterium tumefaciens-mediated DNA transfer. SAC chimeras predominantly assembled into higher order structures (T = 1 and T = 7 VLPs), whereas SAE chimeras assembled into capsomeres or formed aggregates. Four SAC and one SAE chimeras were used in vaccination studies in mice, and their ability to generate cross-neutralizing antibodies was analyzed in HPV pseudovirion-based neutralization assays. Of the seven heterologous HPVs tested, cross-neutralization with antisera specific to chimeras was observed for HPV-11 (SAE 65-18), HPV-18 (SAC 108-120, SAC 65-81, SAC 56-81, SAE 65-81), and HPV-58 (SAC 108-120). Interestingly, only anti-SAE 65-81 antiserum showed neutralization of homologous HPV-16, suggesting that the position of the L2 epitope display is critical for maintaining L1-specific neutralizing epitopes.