Two major pathways of penile carcinogenesis: HPV-induced penile cancers overexpress p16ink4a, HPV-negative cancers associated with dermatoses express p53, but lack p16ink4a overexpression

High-risk human papilloma virus status & outcomes for penile squamous cell carcinoma: A single institution experience

OBJECTIVES

There is a paucity of data on North American cohorts of patients with penile squamous cell carcinoma (pSCC). Herein, we aimed to assess the sensitivity of various modalities to identify human papillomavirus (HPV) status, determine the prevalence of high-risk HPV-positivity, and evaluate the prognostic impact of relevant clinicopathologic variables.

METHODS

Patients with pSCC (n = 121) consecutively treated with partial/total penectomy (2000-2022) at a single institution were included. HPV status (based on immunohistochemistry [IHC], in situ hybridization [ISH], and panviral metagenomic sequencing [PMS]), histologic features, and outcomes were reviewed. Outcome events included death due to disease and progression.

RESULTS

The majority of patients were white (105/121, 86.8%). Thirty-seven (30.6%) were high-risk HPV-positive, and morphologic evaluation had a sensitivity of 97.3% (95% confidence interval [CI], 86.2-99.5) for predicting high-risk HPV status compared to IHC/ISH/PMS. Disease progression was more common among high-risk HPV-negative compared to high-risk HPV-positive patients (HR 2.74, CI 1.12-8.23, P = 0.03). Moreover, among high-risk HPV-negative patients, those with moderate-poorly differentiated tumors had increased disease-specific mortality (32.6%, CI 17.1-48.1) compared to those with well-differentiated tumors (0%). Among high-risk HPV-positive patients, those with basaloid morphology had lower disease-specific mortality (0% vs 14.4%, CI 0.0-33.1).

CONCLUSIONS

We demonstrate high-risk HPV-positivity in approximately one-third of patients with pSCC. Morphologic evaluation alone had a high sensitivity in correctly determining HPV status. Our results suggest that high-risk HPV status and morphologic features (differentiation in high-risk HPV-negative, and basaloid subtype in high-risk HPV-positive pSCC) may have prognostic value.

Insights into the management of penile squamous cell carcinoma: from conventional approaches to emerging novel therapies

INTRODUCTION

Penile squamous cell carcinoma (PSCC), a rare genitourinary cancer, is associated with poor outcomes due to limited treatment effectiveness, especially in advanced stages.

AREAS COVERED

While chemotherapy and/or surgery remain the standard of care, emerging therapies like immunotherapy, targeted therapy, and human papillomavirus (HPV) directed therapies show promise. Key to advancing treatment is understanding the immune microenvironment to gain insights into tumor resistance mechanisms and potential therapeutic targets. The scarcity of data on PSCC is a major obstacle in advancing research for this rare cancer.

EXPERT OPINION

Future research should prioritize collaborative efforts across various research centers and countries. Enhancing data sharing and pooling resources can lead to a more comprehensive understanding of PSCC, ultimately supporting the development of precision medicine strategies tailored to this specific cancer type. This collaborative approach is essential for making significant strides in PSCC treatment and care.

Association between HPV infection and penile cancer and penile intraepithelial neoplasia: A retrospective observational study

BACKGROUND

Penile cancer is rising in most European countries. Several risk factors have been identified, namely human papillomavirus (HPV) infection. However, the exact role of HPV in penile cancer carcinogenesis is still unknown. Clarifying the contribution of HPV in penile cancer is crucial as it may improve prevention and treatment strategies.

OBJECTIVE

To describe the characteristics of patients with penile cancer and penile intraepithelial neoplasia (PeIN), evaluate the prevalence of HPV-DNA in tumour tissue and identify differences between patients with and without HPV-DNA.

METHODS

A retrospective observational study including patients with histological diagnosis of penile squamous cell carcinoma (SCC) or PeIN between 2012 and 2021 in a university hospital was carried out. HPV analysis was performed using Anyplex™ II HPV28 Detection that detects and identifies 28 HPV types. (sensitivity of 95.9%).

RESULTS

A total of 25 patients were included. Most of the tumours identified were invasive SCC (n = 11) and SCC in situ (PeIN 3) (n = 8). PeIN1/2 was found in the remaining six patients. HPV-DNA was tested in all tissue specimens and was detected in 18 of them. High risk HPV DNA was identified in all positive HPV samples, except one. HPV types included in the nonavalent HPV vaccine were identified in 16 of the 18 samples positive for HPV-DNA. Stratifying patients according to HPV-DNA detection, we found that patients with HPV-DNA were younger (57.5 years vs. 70 years, p = 0.047), less likely to have phimosis (5.8% vs. 42.9%, p = 0.022) and more likely to have PeIN lesions than invasive SCC (85.7% vs. 27.8%, p = 0.025).

CONCLUSION

This study shows a prevalence of HPV-DNA in penile SCC and premalignant lesions of 45.5% and 92.9%, respectively. Identifying HPV involvement in SCC and PeIN pathology has the potential to guide treatment and enhance follow-up strategies.

The Spectrum of HPV-independent Penile Intraepithelial Neoplasia: A Proposal for Subclassification

Compared with vulva, precursor lesions of human papillomavirus (HPV)-independent invasive squamous cell carcinoma (SCC) of the penis are insufficiently characterized. We analyzed the histologic and immunohistochemical characteristics of 70 peritumoral precursor lesions and correlated them with the histology and mutational profile of the adjacent HPV-negative invasive penile SCC. Atypical basal keratinocyte proliferation with variously elongated epithelial rete with premature squamatiziation, but regular superficial cornification, termed differentiated penile intraepithelial neoplasia (d-PeIN), were identified adjacent to 42/70 (60%) SCC (36/42 keratinizing ( P <0.001); 3 papillary, and 1 each verrucous, clear cell, sarcomatoid SCC). d-PeIN were associated with chronic inflammatory dermatoses (32/42; P <0.001), p53 overexpression (26/42; P <0.001), and hotspot mutations in TP53 (32/42; P <0.001), CDKN2A (26/42; P <0.001) or both (21/42; P =0.003) in the adjacent SCC. Cytoplasmic p16 ink4a overexpression in 5/42 d-PeIN correlated with CDKN2A missense mutations in the adjacent SCC. In all, 21/70 (30%) cornified verrucous or glycogenated verruciform precursors with minimal atypia and wild-type p53 (18/21; P <0.001) occurred adjacent to verrucous or papillary SCC (17/21; P <0.001) and keratinizing (4/21) SCC, which harbored mutations in HRAS and/or PIK3CA (12/21; P <0.004). Undifferentiated p16 ink4a -negative full-thickness precursors were identified in 7/70 (10%) SCC. Four histologically different HPV-independent penile precursor lesions can be assigned to 2 major genetic/biological pathways with characteristic highly differentiated precursors requiring different clinical management decisions. These include d-PeIN in chronic inflammatory dermatoses, with p53 overexpression and TP53/CDKN2A mutations, and the p53 wild-type verrucous and verruciform precursors unassociated with dermatoses, but with mutations in oncogenes PIK3CA and HRAS .

Different Mutational Landscapes in Human Papillomavirus-Induced and Human Papillomavirus-Independent Invasive Penile Squamous Cell Cancers

Penile squamous cell carcinomas (SCC) are rare cancers that arise after transforming human papillomavirus (HPV) infections or independent of HPV in the background of chronic dermatoses. Limited knowledge about genetic alterations driving penile carcinogenesis comes from studies of mainly small cohorts of typically mixed etiology. In this comparative genetic study of HPV-induced and HPV-independent invasive penile SCC of 156 patients from a single institution in a low-incidence country, hotspots of 50 cancer-relevant genes were analyzed with targeted next-generation sequencing. Seventy-nine of 156 SCC were classified as HPV induced, and 77 of 156 SCC arose independent of HPV. Only 28 (35%) of 79 HPV-induced penile SCC, but 69 (90%) of 77 HPV-independent SCC carried somatic gene mutations. PIK3CA, FGFR3, and FBXW7 mutations occurred in both groups in similar numbers as seen in other human cancers. In contrast, mutations in TP53 (44/77; 57%), CDKN2A (35/77; 45%), and HRAS (13/77; 17%) genes occurred with one exception of a HIV positive patient exclusively in HPV-independent SCC with a frequent co-occurrence of TP53 and CDKN2A mutations (28/77; 42%). Mutations in multiple genes occurred in 9 (11%) of 79 HPV-induced SCC versus 47 (62%) of 77 HPV-independent SCC (χ2; P < .001). More than one mutation per gene (multi hits) was characteristic for HPV-independent SCC in 14 (18%) of 77 compared with only 3 (4%) of 79 HPV-induced SCC (χ2; P < .001). The total number of mutations in HPV-induced penile SCC (47 mutations) was significantly lower than that in HPV-independent SCC (143 mutations; Welsh test; P < .001). The presence of somatic driver gene mutations did not correlate with the age of patients, histology, or tumor stage of the primary SCC in either etiologic group, suggesting that acquisition of driver gene mutations is an early event after invasion. This large cohort analysis identified characteristic differences in mutational landscapes for the 2 etiologies. While genetic mutations in tumor suppressor genes drive HPV-independent penile carcinogenesis, oncogenic action of E6 and E7 substitute for mutations in HPV-induced SCC. A subgroup of patients with advanced SCC may be candidates for targeted therapy and clinical trials, although the majority of advanced penile SCC remain a therapeutic challenge.

Lichen sclerosus: The 2023 update

Lichen sclerosus (LS) is an underdiagnosed inflammatory mucocutaneous condition affecting the anogenital areas. Postmenopausal women are predominantly affected and, to a lesser extent, men, prepubertal children, and adolescents. The etiology of LS is still unknown. Hormonal status, frequent trauma and autoimmune diseases are well-known associations for LS, yet infections do not seem to be clear risk factors. LS pathogenesis involves factors such as a genetic predisposition and an immune-mediated Th1-specific IFNγ-induced phenotype. Furthermore, there is a distinct expression of tissue remodeling associated genes as well as microRNAs. Oxidative stress with lipid and DNA peroxidation provides an enabling microenvironment to autoimmunity and carcinogenesis. Circulating IgG autoantibodies against the extracellular matrix protein 1 and hemidesmosome may contribute to the progression of LS or simply represent an epiphenomenon. The typical clinical picture includes chronic whitish atrophic patches along with itching and soreness in the vulvar, perianal and penile regions. In addition to genital scarring, and sexual and urinary dysfunction, LS may also lead to squamous cell carcinoma. Disseminated extragenital LS and oral LS are also reported. The diagnosis is usually clinical; however, a skin biopsy should be performed in case of an unclear clinical picture, treatment failure or suspicion of a neoplasm. The gold-standard therapy is the long-term application of ultrapotent or potent topical corticosteroids and, alternatively, topical calcineurin inhibitors such as pimecrolimus or tacrolimus. Collectively, LS is a common dermatological disease with a so far incompletely understood pathogenesis and only limited treatment options. To foster translational research in LS, we provide here an update on its clinical features, pathogenesis, diagnosis and (emerging) treatment options.

Increased prevalence of human papillomavirus in fresh tissue from penile cancers compared to non-malignant penile samples: a case-control study

BACKGROUND

HPV has been detected in approximately 50% of invasive penile cancers but with a large span between 24 and 89%, most likely due to different types of tumors and various methods for HPV analysis. Most studies of HPV in penile cancer have been performed using paraffin-embedded tissue, argued to be at risk for contaminated HPV analysis. Viral activity of HPV, by the use of HPV mRNA expression is well studied in cervical cancer, but seldom studied in penile cancer. The aim was to determine prevalence of HPV types in fresh tissue of penile cancers compared to non-malignant age-matched penile controls. Additional aims were to analyze the viral expression and copy numbers of HPV16-positive tumors and 10 mm adjacent to the tumor.

METHODS

Fresh tissue from penile cancer cases was biopsied inside the tumor and 10 mm outside the tumor. Controls were males circumcised for non-malignant reasons, biopsied at surgery. PCR and Luminex assays were used for identification of HPV types. HPV16-positive samples were investigated for copy numbers and expression of HPV16-mRNA.

RESULTS

Among tumors (n = 135) and age-matched controls (n = 105), HPV was detected in 38.5% (52/135) and 11.4% (12/105), respectively (p < 0.001), adjusted odds ratio 12.8 (95% confidence interval 4.9-33.6). High-risk HPV types were found in 35.6% (48/135) of tumors and 4.8% (5/105) of controls (p < 0.001). Among tumors and controls, HPV16 was present in 27.4% (37/135) and 1% (1/105), respectively (p < 0.001). Among HPV16-positive penile cancers, mean HPV16 viral copy/cell was 74.4 (range 0.00003-725.4) in the tumor and 1.6 (range 0.001-14.4) 10 mm adjacent from the tumor. HPV16-mRNA analysis of the tumors and 10 mm adjacent from the tumors demonstrated viral activity in 86.5% (32/37) and 21.7% (5/23), respectively.

CONCLUSIONS

The prevalence of HPV was significantly higher in penile cancer (38.5%) than among age-matched non-malignant penile samples (11.4%). HPV16 predominates (27.4%) in penile tumors. HPV16 expression was more common in penile cancer than in adjacent healthy tissue, strongly suggesting an etiological role for HPV16 in the development of penile cancer.

Clinical significance of p16INK4a and p53 and their involvement in penile cancer development. A literature review

"Background: Human papillomavirus (HPV) E6 and E7 oncoproteins are vital for developing HPV induced penile carcinoma. The viral oncoproteins play a central role in oncogenesis by interacting with several cellular regulatory proteins, such as p16INK4a and p53. Many studies suggest that these proteins showed clinical utility in predicting nodal disease, cancer specific survival, overall survival and even tumor grade. Understanding the molecular mechanism involved in the carcinogenesis of penile cancer could offer biomarkers for disease progression, treatment response and potential targeted therapies; (2) Methods: This paper is a prospective study on a group of 100 patients who underwent prostate surgery during 2013 and 2014 in the Urology Clinic of “Carol Davila” Central Military Emergency University Hospital Bucharest. They were tested for HPV by PCR and IHC (p16) methods; (3) Results: 11 cases (22%) of HPV were found in the cluster of patients tested. PCR and P16 were the HPV diagnostic tests used. In order to determine the consistency of the 2 tests, the Cohen’s kappa coefficient was used at a p level < 0.05. The PCR method had a sensitivity of 81.8% and a specificity of 94.9%. The P16 method had a sensitivity of 63.6% and a specificity of 89.7%."

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.

National trends and survival outcomes of penile squamous cell carcinoma based on human papillomavirus status

Background

There are no series evaluating penile squamous cell carcinoma (pSCC) based on human papillomavirus (HPV) infection. Herein, we present national registry data on clinical and survival outcomes for pSCC based on HPV status.

Methods

We performed a retrospective review of 1224 pSCC patients with known HPV staining from the National Cancer Database. Patients with cM1 disease, those who did not receive treatment, or had missing follow‐up data were excluded. Logistic regression identified factors associated with locally aggressive disease. Univariable, multivariable, and inverse probability of treatment weighting (IPTW)‐Cox proportional hazard modeling were used to assess hazard ratios (HR) associated with overall survival (OS).

Results

After exclusion criteria, we identified 825 cases of which 321 (38.9%) were HPV positive. The HPV‐positivity rate did not significantly change by year. HPV‐positive patients were younger, had lower Charlson‐Deyo performance score, and resided in areas with both lower median household income and lower school education completion. HPV‐positive tumors presented with lower American Joint Committee on Cancer clinical T‐stage (cT), poorer differentiation, lower rates of lymphovascular invasion (LVI), but more node‐positive disease (cN+). For those who underwent lymph node surgery, there were no differences in final pathologic stage, upstaging, or presence of extranodal extension. Only tumor differentiation, LVI, and performance score were independent predictors for locally aggressive disease. HPV status was not a predictor of OS (IPTW‐HR:0.89, p = 0.13).

Conclusions

In the largest series evaluating pSCC based on HPV status, HPV‐positive tumors were associated with lower cT stages, less LVI, but more cN + disease. More studies on prognostic factors are needed, and time may still be immature to use HPV information for risk stratification.

p53 and p16ink4a As Predictive and Prognostic Biomarkers for Nodal metastasis and Survival in A Contemporary Cohort of Penile Squamous Cell Carcinoma

BACKGROUND

Human papilloma virus (HPV) infection is implicated in a proportion of invasive squamous cell carcinoma of the penis (PC). A subset of PC involves dysregulation of the p53 pathway. HPV in situ hybridization (ISH) and p16^ink4a positivity are surrogate markers for HPV infection, and p53 immunohistochemistry (IHC) denotes abnormality in the p53 pathway. There remains an ambiguity with regard to the contribution of both the pathways in the prognosis of PC. We sought to analyze the clinicopathologic characteristics of a cohort of Indian PC patients with respect to p16 ^ink4a and p53 expression.

PATIENTS AND METHODS

A cohort of 123 PC patients was studied for p16^ink4aand p53IHC and HPVISH. The results of these biomarkers were correlated with various clinicopathologic parameters.

RESULTS

p16^ink4a and HPV ISH were positive in 47% and 53% of the tumors, respectively. The proportion of warty, basaloid, or mixed warty-basaloid tumor subtypes showed significant p16^ink4apositivity (P < .0001) compared to other subtypes. Twenty-eight patients were dual negative (p53- /p16^ink4a-), 32 were dual positive (p53+/p16^ink4a+), 38 were p53+/p16^ink4a-, and 25 were p53-/p16^ink4a +. In patients where p16^ink4a was negative, a p53-positive phenotype had a higher propensity for lymph node metastases (OR, 5.42; 95% CI, 1.75-16.80; P = .003). Similarly, p53 positivity dictates nodal involvement in the p16^ink4a-positive subset of tumors (OR, 5.00; 95% CI, 1.23-20.17; P = .024). On multivariate analyses, pathologic subtypes (warty, warty-basaloid, and basaloid) (P < .0001), p16^ink4aexpression (P < .0001), and absence of nodal metastasis (P < .0001) were significant predictors of improved overall (OS) and cancer specific survival (CSS). In Kaplan-Meier analysis, the OS was significantly longer in patients with p16^ink4a + tumors (P < .0001), as was the CSS (P < .0001). Patients with dual positive tumors had a significantly higher OS (P < .001) and CSS (P = .012), in the entire cohort. In the node positive patients, dual positivity was associated with significantly higher OS (P < .0001); however, the median CSS for p53+/p16^ink4a+tumors were not significantly different compared to p53- /p16^ink4a- tumors (P = .064), although there was a trend towards improved CSS.

CONCLUSIONS

There is a strong concordance between p16^ink4aIHC and HPV ISH results. p16^ink4a status is an independent predictor of survival (OS and CSS) in our cohort of PCs. p53 is a predictor of nodal metastasis irrespective of p16 status. Dual positive tumors have a significantly better outcome in comparison to dual negative tumors.

Recent Advances in the Management of Penile Cancer: A Contemporary Review of the Literature

Penile cancer is a rare condition, which mostly affects men in their sixth decade of life. The most common histology is squamous cell carcinoma (SCC), with about half of the cases linked to human papilloma virus (HPV) infection. The lack of awareness and significant social and psychological stigma associated with penile cancer often leads to delays in presentation, diagnosis and management. Timely multidisciplinary care at experienced centers is therefore critical for improving outcomes. For patients with advanced disease, treatment options are limited and prognosis remains poor. Large international efforts are underway to further define the optimal standards of care. Targeted therapies and immune checkpoint inhibitors could potentially play a role in advanced disease and are under evaluation in clinical trials. In this review, we discuss the current management of penile cancer and future directions.

Diagnosis and management of cutaneous and anogenital lichen sclerosus: recommendations from the Italian Society of Dermatology (SIDeMaST)

Lichen sclerosus (LS) is a disabling chronic inflammatory disease of skin and genital mucous membrane causing itch, pain, dysuria and restriction of micturition, and significant sexual dysfunction and dyspareunia both in women and men. If left untreated, LS is associated with a high degree of sclerosis and scarring, as well as with an elevated risk of cancer in the genital area. Although a central role of autoimmunity is suggested, the pathogenesis of LS is still not clearly understood and the disease remains difficult to treat. The goals of treatment of LS are to alleviate symptoms and discomfort, prevent anatomical changes and prevent malignant transformation. This guideline has been developed by an Italian group of experts. It summarizes evidence-based and expert- based recommendations. The highest level of evidence favors the use of topical high potency corticosteroids; second and third lines' treatments include topical calcineurin inhibitors and topical retinoids, respectively. Surgical treatment has become the treatment of choice in male genital LS with persistent phimosis not responsive to medical treatment. The aim of this paper is to offer evidencebased and easily applicable recommendations for the management of LS.

Penile Cancer-Derived Cells Molecularly Characterized as Models to Guide Targeted Therapies

Penile cancer (PeCa) is a common disease in poor and developing countries, showing high morbidity rates. Despite the recent progress in understanding the molecular events involved in PeCa, the lack of well-characterized in vitro models precludes new advances in anticancer drug development. Here we describe the establishment of five human primary penile cancer-derived cell cultures, including two epithelial and three cancer-associated fibroblast (CAF) cells. Using high-throughput genomic approaches, we found that the epithelial PeCa derived- cells recapitulate the molecular alterations of their primary tumors and present the same deregulated signaling pathways. The differentially expressed genes and proteins identified are components of key oncogenic pathways, including EGFR and PI3K/AKT/mTOR. We showed that epithelial PeCa derived cells presented a good response to cisplatin, a common therapeutic approach used in PeCa patients. The growth of a PeCa-derived cell overexpressing EGFR was inhibited by EGFR inhibitors (cetuximab, gefitinib, and erlotinib). We also identified CAF signature markers in three PeCa-derived cells with fibroblast-like morphology, indicating that those cells are suitable models for PeCa microenvironment studies. We thus demonstrate the utility of PeCa cell models to dissect mechanisms that promote penile carcinogenesis, which are useful models to evaluate therapeutic approaches for the disease.

The Biomarker Potential of Caveolin-1 in Penile Cancer

Various types of human cancers were characterized by an altered expression of epithelial or stromal caveolin-1 (CAV1). However, the clinical significance of CAV1 expression in penile cancer remains largely unknown. Here the expression patterns of CAV1 were analyzed in a retrospective cohort (n=43) of penile squamous cell carcinomas (SCC). Upon penile cancer progression, significantly increased CAV1-levels were determined within the malignant epithelium, whereas within the tumor stroma, namely the fibroblastic tumor compartment harboring activated and/or cancer associated fibroblasts, CAV1 levels significantly decline. Concerning the clinicopathological significance of CAV1 expression in penile cancer as well as respective epithelial-stromal CAV1 distributions, high expression within the tumor cells as well as low expression of CAV1 within the stromal compartment were correlated with decreased overall survival of penile cancer patients. Herein, CAV1 expressions and distributions at advanced penile cancer stages were independent of the immunohistochemically proven tumor protein p53 status. In contrast, less differentiated p16-positive tumor epithelia (indicative for human papilloma virus infection) were characterized by significantly decreased CAV1 levels. Conclusively, we provide further and new evidence that the characteristic shift in stromal‐epithelial CAV1 being functionally relevant to tumor progression even occurs in penile SCC.

miRNA Expression Characterizes Histological Subtypes and Metastasis in Penile Squamous Cell Carcinoma

Although microRNAs are described as promising biomarkers in many tumor types, little is known about their role in PSCC. Thus, we attempted to identify miRNAs involved in tumor development and metastasis in distinct histological subtypes considering the impact of HPV infection. In a first step, microarray analyses were performed on RNA from formalin-fixed, paraffin-embedded tumor (22), and normal (8) tissue samples. Microarray data were validated for selected miRNAs by qRT-PCR on an enlarged cohort, including 27 tumor and 18 normal tissues. We found 876 significantly differentially expressed miRNAs (p ≤ 0.01) between HPV-positive and HPV-negative tumor samples by microarray analysis. Although no significant differences were detected between normal and tumor tissue in the whole cohort, specific expression patterns occurred in distinct histological subtypes, such as HPV-negative usual PSCC (95 differentially expressed miRNAs, p ≤ 0.05) and HPV-positive basaloid/warty subtypes (247 differentially expressed miRNAs, p ≤ 0.05). Selected miRNAs were confirmed by qRT-PCR. Furthermore, microarray data revealed 118 miRNAs (p ≤ 0.01) that were significantly differentially expressed in metastatic versus non-metastatic usual PSCC. The lower expression levels for miR-137 and miR-328-3p in metastatic usual PSCC were validated by qRT-PCR. The results of this study confirmed that specific miRNAs could serve as potential diagnostic and prognostic markers in single PSCC subtypes and are associated with HPV-dependent pathways.

TERT promoter mutations in penile squamous cell carcinoma: high frequency in non-HPV-related type and association with favorable clinicopathologic features

Purpose

Penile carcinoma is a rare malignant neoplasm with a largely unknown molecular pathogenesis. Telomerase reverse transcriptase promoter (TERT-p) mutations have been detected in several types of human malignancies. The aim of this study was to investigate the presence of TERT-p mutations in penile squamous cell carcinomas (SCCs) and their associations with clinicopathologic features.

Methods

In this retrospective study, Sanger sequencing was performed to detect TERT-p mutations in formalin-fixed paraffin-embedded tissue samples from 37 patients with penile SCC, 16 patients with cutaneous SCC, and 4 patients with non-neoplastic penile/skin tissue. The expression of p16^INK4a and Ki-67 was investigated via immunohistochemistry. Associations of TERT-p mutation with clinicopathological factors, immunohistochemical results, and clinical outcome were statistically analyzed.

Results

Recurrent TERT-p mutations were identified in 18 out of 37 (48.6%) penile SCCs, including all 3 carcinoma in situ cases. TERT-p mutations were significantly more frequent in non-human papilloma virus (HPV)-related penile SCC types than in non-HPV-related penile SCC based on both histologic classification and p16^INK4a immunoreactivity. Furthermore, TERT-p mutation was associated with a low histologic grade, low mitotic count, absence of necrosis, low Ki-67/MIB-1 labeling index, and absence of lymph node or distant metastasis.

Conclusion

Our study shows TERT-p mutations are the most frequent somatic mutations in penile SCC. In addition, TERT-p mutations are far more frequent in non-HPV-related penile SCC than in HPV-related penile SCC, indicating TERT-p mutations may have a role in tumorigenesis distinct from HPV-related penile SCC.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00432-021-03514-9.

The Immune Microenvironment in Penile Cancer and Rationale for Immunotherapy

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

Importance of HPV in Chinese Penile Cancer: A Contemporary Multicenter Study

Objective: To investigate the HPV DNA prevalence and genotype distribution among penile cancer in China. To identify association between HPV prevalence, different histological subtypes, tumor stage, tumor grade, demographics, comorbidity, and phimosis incidence trend. Standardized HPV DNA detection and p16^INK4a expression were used in a multi-center series of 340 penile squamous cell carcinomas diagnosed from 2006 to 2017.

Materials and Methods: HPV DNA detection and genotyping were examined by a validated kit for 23 different HPV subtypes (PCR-RDB HPV test). The cases with positive HPV DNA were additional tested for p16^INK4a expression to confirm the HPV infection.

Results: Using the PCR-RDB HPV test, overall HPV prevalence was 48.8% (166/340) and that of p16^INK4a expression was 45.6%. In this studied population, HPV16 was the most frequent HPV type detected in HPV-positive cancers (76.5%). HPV18 was the second most common type in penile cancers (15.1%). After pathology review, 307 cases were confirmed as invasive penile cancer, and the other 33 were non-invasive caners. The histologic subtypes of warty, basaloid, clear cell papillary, adenosquamaous and pseudohyperplastic were showed high HPV DNA prevalence. Among invasive cancers, no statistically significant differences in prevalence were observed by tumor grade, tumor stage or lymphnode stage at diagnosis. HPV positive penile cancer incidence significantly increase and the phimosis incidence significantly decrease from 2006 to 2017.

Conclusions: About a half of penile cancers were related to HPV infection. Our findings highlight the phimosis related penile cancers have been declining, the HPV related in the development of penile cancer and a fully aware of regional differences in HPV genotype distribution are tasks for penile cancer control and prevention.

Future directions in advanced penile cancer - mechanisms of carcinogenesis and a search for targeted therapy

Penile squamous cell carcinoma (SCC) is a rare and aggressive urological malignancy. Advanced penile SCC requires multimodal management, including surgery and systemic therapy. Given its rarity, there have been few substantial advances in our understanding of the molecular and genomic drivers of penile SCC, especially for patients with relapsed or advanced disease. In this review, we discuss the molecular and genomic landscape of penile SCC, clinical trials in progress and implications for novel therapeutic targets. Future work should focus on preclinical models to provide a platform for investigation and validation of new molecular pathways for testing of therapeutics.

Early esophageal squamous cell carcinoma in a western series is not associated with active HPV infection

Few data are available concerning human papillomavirus (HPV) in early esophageal squamous cell carcinoma (ESCC) in Western population. Our study intended to determine the prevalence of HPV infection and the histological characteristics in such early tumors. A monocentric and retrospective study was conducted including 86 patients with early ESCC treated by endoscopic resection or esophagectomy, from 2012 to 2018. Histopathological prognostic criteria were evaluated. Immunohistochemistry for p16 and p53 and an HPV mRNA in situ hybridization were performed. The tumors were composed of 25 (29%) in situ carcinomas, 21 (24%) intramucosal carcinomas, and 40 (47%) submucosal carcinomas, of which 34 had a deep infiltration (> 200 μm). Emboli, present in 12 cases, were associated with deep infiltration. P16-positive ESCC accounted for 21% of the patients. It was not correlated with active HPV infection as no cases were found to be positive in RISH analysis for RNA detection of this virus. However, there was a correlation between p16 expression and alcohol or tobacco consumption. The only histopathological criterion correlated with p16 positivity was marked inflammatory infiltrate. Local or distant neoplastic recurrence occurred in 25% of patients. Overall survival was 95.8% and local or metastatic recurrence-free survival was 75%. There was a correlation between positive resection margins and tumor recurrence. In contrast to oropharynx carcinoma, our study showed that ESCC were not associated with an active HPV infection, highlighting the negligible role of this virus in early ESCC carcinogenesis in the Western world.

The relationship between human papillomavirus and penile cancer over the past decade: a systematic review and meta-analysis

Human papillomavirus (HPV) infection appears to play an important role in the development of penile cancer (PeCa), but their relationship remains unclear. Therefore, we performed a systematic review and meta-analysis to elucidate their relationship. We systematically searched Embase, PubMed, Cochrane Library, and Web of Science for case-control studies and cross-sectional studies using polymerase chain reaction (PCR) technology on formalin-fixed paraffin-embedded (FFPE) or paraffin-embedded (PE) PeCa tissues to detect HPV (published between January 1, 2007, and December 29, 2017; no language restrictions). Twenty-two studies were identified, and 1664 cases were available for analysis. The combined HPV infectious risk of PeCa is 51.0% (95% confidence interval [CI]: 43.0%–60.0%). The three most common subtypes of HPV were HPV16 (28.5%), HPV18 (2.3%), and HPV6 (2.3%). The virus was relevantly associated with basaloid (85.5%, 95% CI: 77.2%–93.8%) and warty (50.0%, 95% CI: 35.2%–64.8%) carcinomas. The invasiveness of PeCa was not associated with HPV (χ² = 0.181, df = 1, P < 0.671). HPV infection in PeCa tended to be moderately differentiated (54.4%, 95% CI: 47.7%–61.1%). This study found that almost half of PeCa patients are associated with HPV. The most commonly associated genotype is HPV16, but several other genotypes were also detected. In addition to types 6 and 11, other single low-risk HPV infections have been found to contribute to PeCa to a lesser degree. HPV-positive tumors tend to exhibit warty and/or basaloid features, corresponding to a moderate histological grade. The role of HPV in PeCa should be revisited to provide evidence for the development of PeCa in the presence of HPV infection.

Topographical Evaluation of Penile Lichen Sclerosus Reveals a Lymphocytic Depleted Variant, Preferentially Associated With Neoplasia: A Report of 200 Cases

Since the seminal study of Hart and Helwig in 1975, there are few detailed pathological studies of lichen sclerosus (LS). The aims of this study were to provide a detailed histopathological description of penile LS, as well as to explore its relationship with penile intraepithelial neoplasia (PeIN) or invasive carcinoma. We evaluated 200 patients and designed a topographical approach for the histological evaluation focusing in alterations of the following anatomical layers: squamous epithelium, lamina propria, dartos, and corpus spongiosum. We documented the quantity and topographical location of stromal lymphocytes. The prevalent lesions found were epithelial hyperplasia, atrophy, PeIN, basal cell vacuolization, lamina propria sclerosis, and variable patterns of lymphocytic infiltration. Various unique patterns of stromal sclerosis were described: perivascular, globular, linear, and solid fibrosis/hyalinization; any of them were found to be diagnostic for LS. The variation in the topography and density of lymphocytes was determinant for the identification of LS morphological variants: lichenoid, band-like, lymphocytic depleted, and mixed. A major finding was the identification of the variant designated as lymphocytic depleted LS, which we considered as the morphological prototype of LS associated with penile neoplasia. The detailed description of this complex lesion presented in this study may help pathologists in practice to identify and better define LS. The identification of the special variants suggests a role of the stromal lymphocytes in the process of carcinogenesis. Confirmation of the observations with more studies is necessary to determine the significance of these findings.

Intrinsic radiosensitivity, genomic-based radiation dose and patterns of failure of penile cancer in response to adjuvant radiation therapy

Purpose

Optimal postoperative radiation therapy (PORT) dose is unclear in penile squamous cell carcinoma (PeSCC). Herein, we characterized the radiosensitivity index (RSI) and genomic-adjusted radiation dose (GARD) profiles in a cohort of patients with PeSCC, and assessed the application of GARD to personalize PORT.

Methods

A total of 25 PeSCC samples were identified for transcriptomic profiling. The RSI score and GARD were derived for each sample. A cohort of 34 patients was reviewed for clinical correlation.

Results

The median RSI for PeSCC was 0.482 (range 0.215-0.682). The majority (n = 21; 84%) of cases were classified as radioresistant. PeSCC GARD ranged from 9.56 to 38.39 (median 18.25), suggesting variable therapeutic effects from PORT. We further determined the optimal GARD-based RT doses to improve locoregional control. We found that therapeutic benefit was only achieved in 52% of PeSCC lesions with PORT of 50 Gy, in contrast to 84% benefit from GARD-modeled PORT of 66 Gy. In the clinical cohort, the majority of patients presented with pathological N2 or N3 disease (n = 31; 91%) and was treated with adjuvant concurrent platinum-based chemoradiotherapy (CRT, n = 30; 88%). Fourteen of the 34 patients (41%) had locoregional recurrence (LRR), of which half had LRR within six months of completion of PORT.

Conclusions

The majority of PeSCC are intrinsically radioresistant with a low GARD-based therapeutic effect from PORT dose of 50 Gy, consistent with the observed high rate of LRR in the clinical cohort. A GARD-based strategy will allow personalizing PORT dose prescription to individual tumor biology and improve outcomes.

Practical Molecular Testing in a Clinical Genitourinary Service

CONTEXT.—

Molecular testing is increasingly playing a key role in the diagnosis, prognosis, and treatment of neoplasms of the genitourinary system.

OBJECTIVE.—

To provide a general overview of the clinically relevant molecular tests available for neoplasms of the genitourinary tract.

DATA SOURCES.—

Relevant medical literature indexed on PubMed.

CONCLUSIONS.—

Understanding of the molecular oncology of genitourinary neoplasms is rapidly advancing, and the pathologist must be aware of the practical implications of molecular testing. While many genomic abnormalities are not yet clinically relevant, there is an increasing library of ancillary tests that may guide diagnosis, prognosis, and/or treatment of many neoplasms. Recurrent genomic abnormalities have been identified in many types of renal cell carcinoma, and some types of renal cell carcinoma are specifically defined by the molecular abnormality. Two major routes of developing urothelial carcinoma have been molecularly described. Recurrent translocations involving ETS family genes are found in approximately half of prostate cancer cases. Testicular germ cell tumors typically harbor i(12p). Penile neoplasms are often high-risk human papillomavirus-driven cancers. Nonetheless, even as genitourinary neoplasms are increasingly better understood at the molecular level, further research with eventual clinical validation is needed for optimal diagnosis, prognosis, and treatment of aggressive malignancies in the genitourinary tract.

Organ-Sparing Surgery for a Giant Verrucous Carcinoma of the Penile Shaft: A Case Report and Review of the Literature

Verrucous Carcinoma is a rare but well-differentiated variant of penile squamous cell carcinoma. Its clinical presentation is usually that of an exophytic cauliflower-like lesion with a broad-based growth pattern. We herein report the case of a 61-year-old man who presented with a giant verrucous carcinoma occupying the dorsal surface of the penile shaft. The patient underwent penile-sparing surgery, achieving both disease control and organ preservation. We discuss relevant issues, including clinical features, diagnosis, surgical management, and prognosis and we review the rather sparse literature regarding this rare lesion.

Squamous Carcinoma of the Neovagina after Male-to-Female Reconstruction Surgery: A Case Report and Review of the Literature

Squamous cell carcinoma (SCC) of the neovagina after genital reconstruction surgery is a rare occurrence with only very few cases published up to the present. We report a case of a 43-year-old transgender woman who developed neovaginal SCC 23 years after vaginoplasty. The patient tested positive for high-risk human papillomavirus (HPV). At the time of diagnosis, radiological investigations revealed already existing lymph node and osseous metastases. The treatment consisted of various cycles of chemotherapy and radiation therapy. Unfortunately, the formation of additional metastases, including cerebral, pulmonary, and hepatic metastases, could not be prevented. After comparing the literature on the topic, we conclude that neovaginal carcinoma often appears years and decades after genital reconstruction surgery. We therefore recommend the continuation of regular clinical follow-up for transgender women after postoperative follow-up is completed. With this approach, potential lesions may be detected at an earlier stage and a better outcome may be achieved. Follow-up should include neovaginal examination and cytological smear testing. At a later age, we recommend additional regular prostate-specific antigen (PSA) testing and digital rectal examination (DRE). Moreover, transgender women are advised to take part in mammography screening starting at the age of 50, especially when additional risk factors are present.

Aberrant CEACAM19 expression is associated with metastatic phenotype in penile cancer

Objective

A greater knowledge of the mechanisms of the pathogenesis of penile cancers may assist in the development of more tailored targeted therapy. Herein, we aimed to evaluate the expression of CEACAM19 in penile cancer and to explore its regulatory mechanisms.

Material and methods

This retrospective study enrolled 64 penile cancer patients who underwent penectomy between 2011 and 2015. CEACAM19 expression in tissues was detected by immunohistochemistry, which was analyzed in association with clinicopathological parameters. Kaplan–Meier analysis was performed to evaluate the relationship between CEACAM19 expression and prognosis of patients with penile cancer. Cell Counting Kit-8 assay and clonogenic assay were used to evaluate the cell viability and tumorigenic potential of penile cancer cell line, respectively; wound healing assay and transwell invasion assay were conducted to evaluate the effect of CEACAM19 depletion on cell migration and invasion in penile cancer cells; CEACAM19 protein expression was analyzed by Western blotting. Culture supranatant matrix metalloproteinase 2/9 (MMP2/9) was detected by ELISA.

Results

CEACAM19 was differentially expressed in non-cancerous and penile cancer tissues. Over-expression of CEACAM19 was significantly associated with nodal and distant metastasis, and predicted unfavorable cancer-specific survival in penile cancer. Depletion of CEACAM19 expression suppressed cell proliferation, reduced colony formation, and attenuated cell migration and invasion in Penl1 cells. Furthermore, knockdown of CEACAM19 expression attenuated the levels of p-Smad2/3 and reduced secretion of MMP2/9 in Penl1 cells. The effects of CEACAM19 might result from its function in regulating the Smad2/3 activation, as inhibition on Smad2/3 activation suppressed cell migration and invasion and reduced MMP2/9 secretion in Penl1 cells.

Conclusion

Over-expression of CEACAM19 might serve as a potential prognostic biomarker for clinical management of penile cancer. Strategies targeting CEACAM19-regulated signaling pathways may have a therapeutic benefit in penile cancer.

Prevalence of human papillomavirus DNA and p16INK4a in penile cancer and penile intraepithelial neoplasia: a systematic review and meta-analysis

BACKGROUND

Although previous meta-analyses have examined human papillomavirus (HPV) DNA prevalence in penile cancer, none, to our knowledge, have assessed pooled HPV DNA prevalence in penile intraepithelial neoplasia or p16^INK4a percent positivity in penile cancer and penile intraepithelial neoplasia. Therefore, we aimed to examine the prevalence of HPV DNA and p16^INK4a positivity in penile cancer and penile intraepithelial neoplasia worldwide.

METHODS

In this systematic review and meta-analysis, we searched PubMed, Embase, and the Cochrane Library until July 24, 2017, for English-language articles published from Jan 1, 1986, onwards reporting the prevalence of HPV DNA and p16^INK4a positivity, either alone or in combination, in at least five cases of penile cancer or penile intraepithelial neoplasia. Only studies that used PCR or hybrid capture for the detection of HPV DNA and immunohistochemical staining or methylation for the detection of p16^INK4a were included. Data were extracted and subsequently crosschecked, and inconsistencies were discussed to reach consensus. Using random-effects models, we estimated the pooled prevalence and 95% CI of HPV DNA and p16^INK4a positivity in penile cancer and penile intraepithelial neoplasia, stratifying by histological subtype and HPV DNA or p16^INK4a detection method. Type-specific prevalence of HPV6, HPV11, HPV16, HPV18, HPV31, HPV33, and HPV45 in penile cancer was estimated.

FINDINGS

Our searches identified 1836 non-duplicate records, of which 73 relevant papers (71 studies) were found to be eligible. The pooled HPV DNA prevalence in penile cancer (52 studies; n=4199) was 50·8% (95% CI 44·8-56·7; I²=92·6%, p_{heterogeneity}<0·0001). A high pooled HPV DNA prevalence was seen in basaloid squamous cell carcinomas (84·0%, 95% CI 71·0-93·6; I²=48·0%, p_{heterogeneity}=0·0197) and in warty-basaloid carcinoma (75·7%, 70·1-81·0; I²=0%, p_{heterogeneity}=0·52). The predominant oncogenic HPV type in penile cancer was HPV16 (68·3%, 95% CI 58·9-77·1), followed by HPV6 (8·1%, 4·0-13·7) and HPV18 (6·9%, 2·9-12·4). The pooled HPV DNA prevalence in penile intraepithelial neoplasia (19 studies; n=445) was 79·8% (95% CI 69·3-88·6; I²=83·2%, p_{heterogeneity}<0·0001). The pooled p16^INK4a percent positivity in penile cancer (24 studies; n=2295) was 41·6% (95% CI 36·2-47·0; I²=80·6%, p_{heterogeneity}<0·0001), with a high pooled p16^INK4a percent positivity in HPV-related squamous cell carcinoma (85·8%, 95% CI 72·1-95·4; I²=56·4%, p_{heterogeneity}=0·0011) as compared with non-HPV-related squamous cell carcinoma (17·1%, 7·9-29·1; I²=78·3%, p_{heterogeneity}<0·0001). Moreover, among HPV-positive cases of penile cancer, the p16^INK4a percent positivity was 79·6% (95% CI 65·7-90·7; I²=89·9%, p_{heterogeneity}<0·0001), compared with 18·5% (9·6-29·6; I²=89·3%, p_{heterogeneity}<0·0001) in HPV-negative penile cancers. The pooled p16^INK4a percent positivity in penile intraepithelial neoplasia (six studies; n=167) was 49·5% (95% CI 18·6-80·7).

INTERPRETATION

A large proportion of penile cancers and penile intraepithelial neoplasias are associated with infection with HPV DNA (predominantly HPV16), emphasising the possible benefits of HPV vaccination in men and boys.

FUNDING

None.

A Rare Variant of Penile Squamous Cell Carcinoma in a Man with Paraplegia

Verrucous carcinoma (VC) is a rare variant of squamous cell carcinoma (SCC). It is described as a low grade, slow growing, locally infiltrative neoplasm that accounts for 3%-8% of penile SCCs. Here we report a case of destructive VC of the glans penis in a paraplegic man resulting in a hypospadias from the tip of the glans to the corona. Histology demonstrated exophytic squamous epithelial proliferation with characteristic round, pushing borders. In situ hybridization was positive for both low-risk and high-risk strains of human papillomavirus.

Increased expression of p16 in both oral and genital lichen planus

Background

Lichen Planus, LP, is an inflammatory disease of possible autoimmune origin affecting mainly oral and genital mucosa and skin. According to the WHO oral LP is considered a potentially malignant disorders. The p16 tumour suppressor protein can act as an inhibitor of cyclin dependent kinases 4 and 6 and thus down regulate cell cycle progression. Since the discovery of p16 several studies have evaluated its expression in various forms of human cancers. The aim of this study was to evaluate and compare the expression of p16 in oral and genital LP and corresponding healthy mucosa.

Material and Methods

A total of 76 cases of oral LP (OLP), 34 cases of genital LP (GLP), 12 cases of healthy oral and 9 cases of healthy genital mucosa were analysed by the use of immunohistochemistry.

Results

Data showed p16 to be highly expressed in both oral and genital LP, higher than in oral (p=0.000), and genital controls (p=0.002).

Conclusions

Results suggest that the over-expression of p16 seen in LP play a part in the histopathology of the disease.

Key words:p16, inflammation, oral, genital, lichen planus, malignant risk.

Human papillomavirus (HPV) genotype distribution in penile carcinoma: Association with clinic pathological factors

Background

Penile carcinoma (PC) is a rare, highly mutilating disease, common in developing countries. The evolution of penile cancer includes at least two independent carcinogenic pathways, related or unrelated to HPV infection.

Objectives

To estimate the prevalence, identify HPV genotypes, and correlate with clinicopathological data on penile cancer.

Methods

A retrospective cohort study involving 183 patients with PC undergoing treatment in a referral hospital in Goiânia, Goiás, in Midwestern Brazil, from 2003 to 2015. Samples containing paraffin embedded tumor fragments were subjected to detection and genotyping by INNO-LiPA HPV. The clinicopathological variables were subjected to analysis with respect to HPV positivity and used prevalence ratio (PR), adjusted prevalence ratio (PRa) and 95% confidence interval (CI) as statistical measures.

Results

The prevalence of HPV DNA in PC was 30.6% (95% CI: 24.4 to 37.6), high-risk HPV 24.9% (95% CI: 18.9 to 31.3), and 62.5% were HPV 16. There was a statistical association between the endpoints HPV infection and HPV high risk, and the variable tumor grade II-III (p = 0.025) (p = 0.040), respectively. There was no statistical difference in disease specific survival at 10 years between the HPV positive and negative patients (p = 0.143), and high and low risk HPV (p = 0.325).

Conclusions

The prevalence of HPV infection was 30.6%, and 80.3% of the genotypes were identified as preventable by anti-HPV quadrivalent or nonavalent vaccine. HPV infections and high-risk HPV were not associated with penile carcinoma prognosis in this study.

PIK3CA copy number aberration and activation of the PI3K-AKT-mTOR pathway in varied disease states of penile cancer

BACKGROUND

Therapeutic targeting of the PI3K-AKT-mTOR pathway may benefit patients with advanced penile squamous cell carcinoma (PSCC).

OBJECTIVES

To determine the prevalence of PIK3CA copy number gain and correlate this with the activity status of PI3K-AKT-mTOR pathway in pre-malignant penile intraepithelial neoplasia (PeIN) and invasive PSCC.

MATERIALS AND METHODS

Archival tissue blocks were obtained from 58 PeIN and 244 primary PSCC patients treated at St George's Hospital. PIK3CA copy number status (CNS) was assessed by fluorescence in-situ hybridisation. High-risk HPV DNA was detected with INNO-LiPA assay. p16INK4A, p-AKT and p-mTOR protein expression were assessed using immunohistochemistry (IHC).

RESULTS

Increased prevalence of PIK3CA copy number gain was seen in PSCC in comparison to PeIN (84/199 (42%) vs. 10/58 (17%); p = 0.0009). Analysis of the p-AKT and p-mTOR revealed a tendency to a more common expression of cytoplasmic p-AKT (p = 0.1318), nuclear p-AKT (p<0.0001) and cytoplasmic mTOR (p = 0.0006) in PeIN than PSCC. A significant association between p-AKT cytoplasmic immunoexpression and PIK3CA CNS (p = 0.0404) was found in PeIN.

CONCLUSION

Overall, PIK3CA copy number gain correlated with activation of the PI3K-AKT-mTOR pathway in PeIN and activation of this pathway is primarily involved in early penile carcinogenesis. Based on these results therapeutic targeting of this pathway in advanced PSCC is unlikely to produce significant clinical benefit. Future studies will need to focus on alternative therapeutic targets.

The Prognostic Value of Immune Factors in the Tumor Microenvironment of Penile Squamous Cell Carcinoma

The host's immune system plays a pivotal role in many tumor types, including squamous cell carcinomas (SCCs). We aim to identify immunological prognosticators for lymph node metastases (LNM) and disease-specific survival (DSS) in penile SCC. For this retrospective observational cohort study, penile SCC patients (n = 213) treated in the Netherlands Cancer Institute, were selected if sufficient formalin-fixed, paraffin-embedded tumor material was available. Analysis included previously described high-risk human papilloma virus (hrHPV) status, immunohistochemical scores for classical and non-classical human leukocyte antigen (HLA) class I, programmed death ligand-1 (PD-L1) expression, and novel data on tumor-infiltrating macrophages and cytotoxic an regulatory T-cells. Clinicopathological characteristics and extended follow-up were also included. Regression analyses investigated relationships of the immune parameters with LNM and DSS. In the total cohort, diffuse PD-L1 tumor-cell expression, CD163+ macrophage infiltration, non-classical HLA class I upregulation, and low stromal CD8+ T-cell infiltration were all associated with LNM. In the multivariable model, only tumor PD-L1 expression remained a significant predictor for LNM (odds ratio (OR) 2.8, p = 0.05). hrHPV negativity and diffuse PD-L1 tumor-cell expression were significantly associated with poor DSS and remained so upon correction for clinical parameters [hazard ratio (HR) 9.7, p < 0.01 and HR 2.8, p = 0.03]. The only immune factor with different expression in HPV+ and HPV- tumors was PD-L1, with higher PD-L1 expression in the latter (p = 0.03). In the HPV- cohort (n = 158), LNM were associated with diffuse PD-L1 tumor-cell expression, high intratumoral CD163+ macrophage infiltration, and low number of stromal CD8+ T-cells. The first two parameters were also linked to DSS. In the multivariable regression model, diffuse PD-L1 expression remained significantly unfavorable for DSS (HR 5.0, p < 0.01). These results emphasize the complexity of the tumor microenvironment in penile cancer and point toward several possible immunotherapy targets. Here described immune factors can aid risk-stratification and should be evaluated in clinical immunotherapy studies to ultimately lead to patient tailored treatment.

HPV-independent Differentiated Vulvar Intraepithelial Neoplasia (dVIN) is Associated With an Aggressive Clinical Course

Differentiated vulvar intrapeithelial neoplasia (dVIN) is an human papillomavirus (HPV)-independent precursor of squamous cell carcinoma (SCC), and the aim of this study was to better characterize its natural history. Cases of dVIN were identified from the pathology archives. Outcomes of patients with dVIN only, without associated invasive SCC, were compared with a cohort of patients with high-grade squamous intraepithelial lesion [HSIL(VIN3)]. Eighteen patients diagnosed with dVIN with adjacent invasive SCC (SCC/dVIN) and 7 patients with dVIN only, without invasive carcinoma, were identified. Mean age in both cohorts was 75 yr. All lesions but 1 were unifocal. In 35% of SCC/dVIN cases the surgical resection margins were positive for SCC, with 75% and 60% having margins positive for dVIN in the SCC/dVIN and dVIN-only cohorts, respectively. In total, 23/25 women with dVIN only or dVIN/SCC, for whom there was follow-up information, experienced either progression to or recurrence of invasive SCC, respectively, at a median of 1.1 yr, including all but 1 case of dVIN only, where the median time of progression to invasive SCC was 1.9 yr. A total of 22/25 women died of disease with a median overall survival of 3.4 yr. The outcome (i.e. progression to invasive carcinoma) of patients with dVIN only was significantly worse than that of a comparison group of 18 patients with HSIL(VIN3) (progression-free survival log-rank, P<0.001; disease-specific survival, P=0.04; overall survival, P=0.01). Six of 7 patients with dVIN only developed invasive carcinoma on follow-up, compared with 0 of 18 patients with HSIL(VIN3). The diagnosis of dVIN indicates the presence of a high-risk human papillomavirus-negative precursor of invasive SCC. These patients are likely to progress to invasive carcinoma over a relatively short period, at which point their prognosis is guarded.

Photodynamic therapy with topical photosensitizers in mucosal and semimucosal areas: Review from a dermatologic perspective

Photodynamic Therapy is a procedure based on the interaction between a Photosensitizer, a light source with a specific wavelength and oxygen. The aim of this review is to provide a brief and updated analysis of scientific reports on the use of PDT with topical PS in the management of oncological, infectious, and inflammatory disorders involving mucosal and semimucosal areas, with a specific focus on diseases of dermatologic interest.

The relationship between HPV status and chemoradiotherapy in the locoregional control of penile cancer

BACKGROUND

Penile cancer (PeCa) is a rare, aggressive malignancy often associated with the human papillomavirus (HPV). The practice of a personalized risk-adapted approach is not yet established. This study is to assess the relationship between HPV tumor status and chemoradiotherapy (CRT) in PeCa locoregional control (LRC).

METHODS

We retrospectively identified patients with HPV status who were diagnosed with squamous cell carcinoma of the penis and treated with surgical resection between 1999 and 2016. The relationship between tumor/treatment characteristics and LRC were analyzed with univariate and multivariate Cox proportional hazard regression analysis (UVA and MVA, respectively). Time-to-event outcomes were estimated with Kaplan-Meier curves and compared via log-rank tests.

RESULTS

Fifty-one patients were identified. The median follow-up was 36.6 months. Patients were primarily HPV-negative (HPV-) (n = 28, 55%), and pathologic node positive (pN+) (55%). The 2 year LRC rate was 54%. pN+ patients had a significantly lower 2 year LRC (37 vs. 81%, p = 0.002). In the subgroup analysis of pN+ patients (n = 28), there was a LRC benefit associated with the addition of CRT (HR 0.19; 95% CI 0.05-0.70, p = 0.012) and HPV-positive (HPV+) disease (HR 0.18; 95% CI 0.039-0.80, p = 0.024) using MVA. HPV+ patients treated with CRT had improved 2 year LRC compared to HPV- patients (83 vs. 38%, p = 0.038).

CONCLUSIONS

Adjuvant CRT and HPV+ disease independently predicted for improved LRC in pN+ PeCa. In HPV+ PeCa, the LRC benefit was primarily observed in patients treated with adjuvant CRT. Prospective investigation of HPV+ and CRT is required to further delineate their roles in optimizing PeCa treatment.

Lichen Sclerosus-Presentation, Diagnosis and Management

BACKGROUND

Lichen sclerosus is a chronic inflammatory skin disease. It is thought to be underdiagnosed and undertreated. If it is not treated, lichen sclerosus is associated with a greater degree of scarring and an elevated risk of cancer in the genital area.

METHODS

This review is based on pertinent articles published up to October 2015 that were retrieved by a selective search in PubMed, Embase, and the Cochrane Library and on the European S3 guideline for lichen sclerosus.

RESULTS

Lichen sclerosus is mainly found in the anogenital area but can also be generalized. Extragenital involvement is reportedly present in 6% to 20% of patients. Neighboring mucous membranes, such as the vaginal or oral mucosa, are not typically affected. The disease is more common in women than in men, and occurs more often in adults than in children. About 10% of patients have other family members with the same condition. Anogenital lichen sclerosus often causes itching and pain. Functional impairment due to fissures and scars can arise over the course of the condition. The treatment of first choice is the local application of high-potency corticosteroids as early as possible (1/A). For boys and men in whom the condition does not remit after steroid treatment, circumcision is indicated (3/D).

CONCLUSION

Anogenital itching and clinical features such as erythema, white skin changes (such as hyperkeratosis and sclerosis), and fissures should arouse suspicion of lichen sclerosus. The diagnosis should be confirmed with a skin biopsy, and early, thorough treatment should be initiated. In this way, a mutilating disease course can be averted, and the risk of cancer can be lessened.

Insight into novel biomarkers in penile cancer: Redefining the present and future treatment paradigm?

INTRODUCTION

Biomarkers are increasingly used in the diagnosis and management of various malignancies. Selected biomarkers may also play a role in management of certain cases of penile carcinoma. In this article, we provide an overview of the clinical role of such markers in the management of penile cancer.

METHOD

This is a nonsystematic review of relevant literature assessing biomarkers in penile carcinoma.

RESULTS

Evidence of infections with human papillomavirus and its surrogate markers may have important prognostic value in patients with localized or metastatic penile cancer. Squamous cell carcinoma antigen, p53, C-reactive protein, Ki-67, proliferating cell nuclear antigen, cyclin D1, as well as other markers have been studied with various degree of evidence in support of clinical utility in penile cancer.

CONCLUSIONS

No single marker may have all the answers, and future research should focus on genomic analysis of individual penile tumors, attempting to identify specific targets for treatment.

p16 Immunostaining Allows for Accurate Subclassification of Vulvar Squamous Cell Carcinoma Into HPV-Associated and HPV-Independent Cases

The aim of this study was to compare morphologic assessment and p16 immunohistochemistry (IHC) in the determination of human papilloma virus (HPV) status in vulvar squamous cell carcinoma (VSCC). A total of 201 invasive VSCC cases were classified as "HPV-associated" when warty/basaloid VSCC or high-grade squamous intraepithelial lesion (vulvar intraepithelial neoplasia 2/3) was observed, or "HPV-independent" in the presence of well-differentiated keratinizing invasive SCC or differentiated vulvar intraepithelial neoplasia. For p16 IHC, strong nuclear and cytoplasmic staining of all cells in at least the lowermost third of the epithelium was scored as positive. All cases with discrepant HPV predictions by hematoxylin and eosin morphology versus p16 IHC were further analyzed by polymerase chain reaction for HPV DNA. On the basis of hematoxylin and eosin morphologic assessment, 50/201 tumors showed features suggestive of HPV-associated, and 47 of those showed p16 immunoreactivity (94% concordance). Of the 146 cases considered HPV-independent based on hematoxylin and eosin, 115 (79%) showed negative p16 immunostaining. Thus 83% (162/196) concordance between morphologic assessment and p16 IHC was observed, overall. In 34 cases, where morphologic assessment and p16 IHC did not agree, HPV polymerase chain reaction agreed with p16 IHC in 32/34 (94%). The sensitivity and specificity of p16 IHC in classification of VSCC as HPV-independent or HPV-associated was 100% and 98.4%, respectively. Morphologic assessment and p16 IHC are concordant in classifying VSCC as HPV-independent or HPV-associated in a majority of cases (83%). Most of the discrepant cases are p16-positive well-differentiated keratinizing VSCC, and HPV polymerase chain reaction supports classification of a large majority of these (94%) as HPV-associated. p16 IHC is validated as an accurate surrogate marker for determination of HPV status in VSCC.

Advances in Understanding of Penile Carcinogenesis: The Search for Actionable Targets

Penile cancer (PeCa) is a rare malignancy with potentially devastating effects. Squamous cell carcinoma is the most common variant with distinct precancerous lesions before development into invasive disease. Involvement of the inguinal lymph nodes is the most important prognostic factor in PeCa, and once disease is present outside the groin, prognosis is poor. Metastatic PeCa is challenging to treat and often requires multidisciplinary approaches in management. Due to its rarity, molecular understanding of the disease continues to be limited with most studies based on small, single center series. Thus far, it appears PeCa has diverse mechanisms of carcinogenesis affecting similar molecular pathways. In this review, we evaluate the current landscape of the molecular carcinogenesis of PeCa and explore ongoing research on potential actionable targets of therapy. The emergence of anti-epidermal growth factor receptor (EGFR) and other immunotherapeutic strategies may improve outcomes for PeCa patients.

HPV-negative penile squamous cell carcinoma: disruptive mutations in the TP53 gene are common

The majority of penile squamous cell carcinomas is caused by transforming human papilloma virus (HPV) infection. The etiology of HPV-negative cancers is unclear, but TP53 mutations have been implicated. Archival tissues of 108 invasive squamous cell carcinoma from a single pathology institution in a low-incidence area were analyzed for HPV-DNA and p16^ink4a overexpression and for TP53 mutations by ion torrent next-generation sequencing. Library preparation failed in 32/108 squamous cell carcinomas. Institutional review board approval was obtained. Thirty of 76 squamous cell carcinomas (43%; average 63 years) were HPV-negative with 8/33 squamous cell carcinomas being TP53 wild-type (24%; average 63 years). Twenty-five of 33 squamous cell carcinomas (76%; average 65 years) showed 32 different somatic TP53 mutations (23 missense mutations in exons 5-8, 6 nonsense, 1 frameshift and 2 splice-site mutations). Several hotspot mutations were detected multiple times (R175H, R248, R282, and R273). Eighteen of 19 squamous cell carcinomas with TP53 expression in immunohistochemistry had TP53 mutations. Fifty percent of TP53-negative squamous cell carcinomas showed mostly truncating loss-of-function TP53 mutations. Patients without mutations had longer survival (5 years: 86% vs 61%; 10 years: 60% vs 22%), but valid clinically relevant conclusions cannot be drawn due to different tumor stages and heterogeneous treatment of the cases presented in this study. Somatic TP53 mutations are a common feature in HPV-negative penile squamous cell carcinomas and offer an explanation for HPV-independent penile carcinogenesis. About half of HPV-negative penile cancers are driven by oncogenic activation of TP53, while a quarter is induced by loss of TP53 tumor suppressor function. Detection of TP53 mutations should be carried out by sequencing, as immunohistochemical TP53 staining could not identify all squamous cell carcinomas with TP53 mutations.