Incidence trends and survival outcomes of penile squamous cell carcinoma: evidence from the Surveillance, Epidemiology and End Results population-based data

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.

A Clinical Nomogram for Predicting Overall Survival in Patients With T1/T2 Penile Squamous Cell Carcinoma

BACKGROUND

To evaluate the overall survival (OS) and construct a nomogram to predict the OS of patients with penile squamous cell carcinoma (PSCC).

METHODS

This retrospective study analyzed data of patients with PSCC from the First Affiliated Hospital of Soochow University between 2012 and 2022. R software was used to explore factors influencing OS in PSCC. Kaplan-Meier method and log-rank test were employed for OS estimation. Univariate and multivariate Cox proportional hazards regression analyses were performed to identify these factors. A nomogram was created to identify the independent prognostic factors. The model was evaluated by concordance index, receiver operating characteristic (ROC) curves, and calibration plots.

RESULTS

A total of 159 patients with T1/T2 PSCC were included in the analysis. Patients with T2/N2 stage, older age, larger tumor size, high preoperative systemic immune-inflammation index (SII), and poor preoperative nutrition had a higher incidence of poor OS. Age, T/N stage, tumor size, and SII were identified as independent prognostic indicators. A prognostic nomogram was formulated, and its predictive accuracy for estimating OS in PSCC patients was validated through ROC curves and calibration plots.

CONCLUSION

The nomograms, based on age, T/N stage, tumor size, and high preoperative SII, provide a valuable tool for predicting 1-, 2-, and 3-year OS in patients with T1/T2 PSCC without distant metastases.

A population-based analysis of the epidemiology of penile cancer in Newfoundland and Labrador

INTRODUCTION

Penile cancers are a rare subset of carcinomas accounting for <1% of all diagnosed malignancies. There have been recent reports of increasing incidence globally; however, there is limited Canadian literature pertaining to these neoplasms. The province of Newfoundland and Labrador (NL ) represents an important entity to study, possessing the highest national incidence of cancer, along with a plethora of relevant risk factors for penile cancer.

METHODS

A retrospective chart analysis of all patients with a diagnosis of penile cancer in NL between the years of 2006 and 2018 was conducted. The main outcomes included overall incidence, proportion with metastatic disease, tumor demographics, and overall survival (OS ). Incidence among the male population was calculated using Statistics Canada annual reports.

RESULTS

An identified 81 cases satisfied the inclusion criteria, with a median age at diagnosis of 65 (interquartile range 20) years. Crude incidence of penile cancer ranged from 1.20-4.27/100 000 males in 2007 and 2010, respectively, while the average age-standardized incidence was 2.34/100 000 males across the study timeframe. Metastatic disease was noted in 17 (21.0%) patients, with a five-year OS of 74% for all penile malignancies, decreasing to 66% in those with invasive squamous cell carcinoma.

CONCLUSIONS

The incidence of penile cancer in our population was higher than reported Western jurisdictions and showed frequent rates of metastatic spread. These observations are likely multifactorial, resultant of chronic inflammation paired with high rates of modifiable risk factors and diagnostic delays. An evident need for greater examination and improved reporting of these malignancies in the province was identified.

Penile Cancers Attributed to Human Papillomavirus Are Associated with Improved Survival for Node-positive Patients. Findings from a Norwegian Cohort Study Spanning 50 Years

BACKGROUND

Human papillomavirus (HPV) infection is a risk factor for the development of penile squamous cell carcinoma (PSCC). It remains inconclusive whether HPV-related PSCC has a different prognosis from non-HPV-related PSCC.

OBJECTIVE

To investigate the relationship between HPV status and survival as well as temporal changes in the proportion of HPV-related PSCC.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective cohort of 277 patients treated in Norway between 1973 and 2022 was investigated for HPV DNA in tumor tissue. Clinicopathological variables and disease course were registered.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Kaplan-Meier curves and Cox regression were used to investigate the determinants of cancer-specific survival (CSS). The chi-square test for trend in proportions enabled investigation of temporal changes in the HPV-related proportion of PSCC patients treated in Western Norway (n = 211).

RESULTS AND LIMITATIONS

HPV DNA was detected in tumor tissue from 131 (47%) patients. Stratified by HPV status, 5-yr CSS did not differ between groups (p = 0.37). When investigating only node-positive patients, however, presence of HPV DNA was an independent predictor of better survival in multivariable Cox regression after adjustment for age, nodal stage, and adjuvant therapy (hazard ratio 0.54, 95% confidence interval: [0.30-0.99], p = 0.04). In cases from Western Norway, an increasing proportion of HPV-related cases over time was found (p = 0.01). The main limitation is the retrospective study design.

CONCLUSIONS

HPV DNA in tumor tissue was associated with significantly better CSS for node-positive patients. The proportion of HPV DNA-positive PSCC has increased significantly in Western Norway over the past 50 yr.

PATIENT SUMMARY

We investigated the impact of human papillomavirus (HPV) on the survival of penile cancer patients treated over a 50-yr period in Norway. We found that for patients with lymph node metastasis, survival was better for HPV-related cases. We also found that the proportion of cases due to HPV has increased in Western Norway.

Racial differences in survival for early stage (T1) penile cancer: Analysis from the SEER database

BACKGROUND

Penile cancer accounts for less than 1% of male cancers in the United States. Localized disease, particularly T1 tumors are potentially curable with local therapy. We present the racial differences in survival outcomes for T1, penile cancer from the SEER database.

METHODS

From 2004 to 2016 all men with T1, N0, M0 penile cancer in the SEER-18 database were included. Kaplan-Meier analysis and multivariable Cox-Regression analysis were conducted to investigate prognostic variables for cancer specific survival (CSS).

RESULTS

A total of 4,406 men were identified with penile cancer; 1,941 men had T1 disease. The Kaplan-Meier (KM) analysis showed those with primary site surgery had better 5-year CSS compared to those without primary site surgery (P <.0001) and a significant difference in CSS based on race (P= 0.0078). On multivariable analysis, Hispanic individuals had worse CSS (HR 1.92; P = 0.0057) compared to the White men. Black men were also found to have a poor CSS however this was not statistically significant (HR 1.53, P = 0.118). Men with penile cancer who had either penectomy (HR 0.45; P = 0.006) or penile preservation surgery (HR 0.25; P< 0.001) had improved CSS.

CONCLUSION

Racial disparities in CSS exist among men with in early-stage penile cancer. KM analysis showed significant differences in CSS by race and in those receiving primary site surgery. On multivariable analysis, the CSS is worse in Hispanic compared to White men. There is a trend towards worse CSS in Black men however this was not statistically significant.

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.

Penile squamous cell carcinoma exclusive to the shaft, with a proposal for a novel staging system

Penile squamous cell carcinomas (SCC) originating in the shaft are rare. pT1/pT2 categories in the American Joint Committee on Cancer (AJCC) staging manual (8th edition) are poorly defined for SCCs arising in the dorsal shaft as anatomic structures differ between the glans and dorsal shaft (corpus spongiosum vs dartos/Buck's fascia, respectively). We reviewed six penile SCC cases exclusive to the shaft, an unusual presentation, identified amongst 120 patients treated with penectomy. We propose a novel pT staging system for dorsal shaft tumors tailored to its anatomic landmarks, where tumors extending to Buck's fascia are considered pT2 instead of pT1. The mean age at penectomy, average duration of follow-up, and mean depth of invasion were 64 years, 45 months, and 9.8 mm, respectively. Four cases were moderately differentiated, HPV-negative SCCs of the usual type and two cases were HPV-positive basaloid and warty-basaloid carcinomas. Three cases had nodal or distant metastasis at the time of penectomy, and histologic assessment in these cases showed invasion into the Buck's fascia or deeper. According to the current AJCC system, only one of these three cases would be staged as ≥ pT2. In contrast, all three metastatic tumors would be staged as ≥ pT2 in the proposed model. At last follow-up, one patient died of disease-related complications. Based on this limited series, the proposed staging model appears to suggest better patient stratification for pT1/pT2 stages. This model incorporates Buck's fascia, which has been postulated as a pathway of tumor infiltration. Additional studies are needed to validate this model.

The relationship of human papillomavirus positivity with tumor characteristics in an Irish penile cancer population

INTRODUCTION

Penile cancer is a rare malignancy, with a European-wide annual incidence rate of 1/100 000 males. Approximately one-third of cases are attributable to human papillomavirus (HPV) infection. p16^INK4a is a recognized surrogate marker for HPV infection in penile cancer. University Hospital Waterford (UHW) is the national referral center for penile cancer in Ireland. We report the prevalence of HPV infection and histological characteristics of an Irish penile cancer cohort using p16^INK4a as a surrogate marker.

METHODS

Patients who attended UHW for penile cancer surgery between June 2015 and November 2020 were entered into a prospectively maintained database. Clinical, histopathological, and outcome data were collected.

RESULTS

Over the study period, 70 patients with a histological diagnosis of penile squamous cell carcinoma had staining for p16^INK4a, of whom 64% were positive. p16^INK4a-positive patients were significantly younger at diagnosis, with a mean age of 61±15 years compared to 68±12 (p <0.05). Of note, 97% of tumors with high-risk histology were p16^INK4a-positive (p<0.001). p16^INK4a positivity was more prevalent among higher-grade tumors (p<0.02). Interestingly, p16^INK4a status was not associated with recurrence-free or overall survival.

CONCLUSIONS

Our data is representative of the Irish landscape in penile cancer over the last five years. Using p16^INK4a staining, we demonstrate a high rate of HPV prevalence in penile cancer cases in our patient cohort, which is associated with prognostically worse tumor subtypes. This would suggest that HPV vaccination of adolescent boys is a useful public health intervention in preventing penile cancer in the Irish male population.

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.

Emerging Therapies in Penile Cancer

Advances in the treatment of rare tumors like penile cancer were always hampered by the lack of deep comprehension of the molecular biology and genomic and epigenomic alterations involved in carcinogenesis and tumor progression, as well as by the difficulty in recruitment of patients for prospective clinical trials. Despite the high rates of cure in early localized penile cancers with surgery or other local procedures, locally advanced and metastatic tumors require systemic treatment, with chemotherapy being the current standard, but with high toxicity and no proven real impact on survival. Recent important findings of frequent genomic alterations and mutation signatures in penile cancer have motivated several trials in new modalities of systemic treatments, especially immunotherapy. This review aims to present the most recent advances and the prospect of new modalities of systemic therapies with ongoing studies in penile cancer.

Trends in Incidence, Mortality, and Survival of Penile Cancer in the United States: A Population-Based Study

Purpose

The aim of this study is to investigate the trends in incidence and mortality, and explore any change in survival of penile cancer in the United States.

Methods

We obtained data from the Surveillance, Epidemiology, and End Results (SEER) database (2000–2018) utilizing the SEER Stat software. The joinpoint regression was used to analyze the secular trend of incidence and incidence-based mortality (IBM) stratified by age, race, and summary stage. The 5-year relative survival rate was also calculated.

Result

The age-adjusted rates of penile cancer patients were 0.38 (0.37–0.39) and 0.21 (0.2–0.21) for overall incidence and IBM, respectively. The 5-year relative survival rates were 67.7%, 66.99%, and 65.67% for the calendar periods of 2000–2004, 2005–2009, and 2010–2014, respectively. No significant changes in incidence by era were observed from 2000 to 2018 [annual percentage change (APC) = 0.5%, p = 0.064]. The IBM rate of penile cancer showed an initial significant increase from 2000 to 2002 (APC = 78.6%, 95% CI, −1.7–224.6) followed by a deceleration rate of 4.6% (95% CI, 3.9–5.3) during 2002 to 2018. No significant improvement in 5-year relative survival was observed. The trends by age, race, and summary stage in incidence and IBM were significantly different.

Conclusion

This study, using population-level data from the SEER database, showed an increasing trend in IBM and no significant improvement in the 5-year relative survival rate. Meanwhile, the incidence of penile cancer exhibited a relatively stable trend during the study period. These results might be due to the lack of significant progress in the treatment and management of penile cancer patients in the United States in recent decades. More efforts, like increasing awareness among the general population and doctors, and centralized management, might be needed in the future to improve the survival of this rare disease.

Inguinal lymph node density as a powerful predictor of cancer specific survival in patients with node-positive penile cancer

INTRODUCTION

Penile cancer (PC) is an aggressive malignancy in which the most important prognostic factor for cancer specific survival (CSS) is the involvement of regional lymph nodes (LNs). Lymph node density (LND) could become a superior prognostic tool for CSS, by accounting for both extent of dissection and nodal disease burden. We aim to validate LND as a prognostic factor for CSS in a contemporary series of patients with PC treated and followed at a single high-volume center, treating more than 25 PC patients per year, over a 13-year period.

METHODS

Clinical charts of all patients with PC who underwent surgical treatment between 2007 and 2020 were reviewed. Clinicopathological data was collected and analyzed retrospectively. We only included patients with ≥ 8 LNs removed in a unilateral ILND or ≥16 LNs when a bilateral approach was used. We attempted to find an optimal threshold for LND, capable of maximizing effect difference in terms of CSS and RFS between dichotomized groups. To determine this threshold, we used the chi-squared and the Mann-Whitney tests, and it was required to fulfill the proportional hazards assumption. We assessed different thresholds previously reported in the literature. In our study the optimal threshold for LND was determined to be ≤ 20% Descriptive statistics were used to summarize patient characteristics, CSS and RFS were graphically represented by Kaplan-Meier estimates. Harrell's C index for CSS and RFS were calculated for LND and pN stage, to determine which variable has a superior predictive capacity RESULTS: We identified 110 patients with PC who underwent ILND at our institution, of these, 87 were node-positive and were included in the final analysis. Overall estimates of CSS showed a 3-year CSS of 43% (95% CI: 32-54), the estimated 3-year CSS for the patients with a LND ≤ 20% was 69% (95% CI: 50-82) and 26% (95% CI: 14-39) in the group with a LND >20% (Log-rank P = 0.001). The estimated 3-year RFS for the patients with LND ≤ 20% was 61% (95% CI: 42-76) and 30% (95% CI: 16-44) in the group with a LND >20% (Log-rank P = 0.009). The results of univariate analysis indicate that in patients with a LND >20% the risk for cancer specific mortality was increased (HR 2.68; 95% CI: 1.45-4.98, P =  0.002) compared with LND ≤ 20%. In the and Cox multivariate analysis after Adjusting for age and pN stage the association increased (HR 2.73; 95%, CI 1.38-5.40, P = 0.004). Harrell´s C index for CSS was 0.63 for LND vs. 0.54 for pN stage, suggesting a 9% higher concordance for LND and CSS.

CONCLUSIONS

Lymph node density stands as a promising tool for risk-stratifying patients with node-positive PC after ILND. In this retrospective study, LND was a significant predictor of CSS and RFS when using a LND >20% threshold, and also showed a superior predictive ability than pN stage. These results support the use of the LND parameter in clinical practice with a final goal to improve risk stratification, and individualized adjuvant treatment decision-making to patients with high-risk of cancer specific mortality.