Differentiated precursor lesions and low-grade variants of squamous cell carcinomas are frequent findings in foreskins of patients from a region of high penile cancer incidence

Pathology of Squamous Cell Carcinoma of the Penis: Back to Square One

The landscape of squamous cell carcinoma of the penis (SCC-P) has undergone a significant transformation since the new World Health Organization classification of genitourinary cancers and recent European Association of Urology/American Association of Clinical Oncology guidelines. These changes emphasize the necessity to categorize SCC-P into 2 groups based on its association with human papillomavirus (HPV) infection. This shift has major implications, considering that prior knowledge was derived from a mix of both groups. Given the distinct prognosis, treatment options, and staging systems observed for HPV-associated tumors in other body areas, the question now arises: will similar patterns emerge for SCC-P?

Malignant Neoplasms of the Penis with Radiologic and Pathologic Correlation

Penile malignancy is the third most common male-specific genitourinary malignancy, with squamous cell carcinoma representing the most common histologic type. Squamous cell carcinoma is an epithelial malignancy, frequently developing from the mucosal surfaces of the foreskin, glans, and coronal sulcus and manifesting as a distal infiltrative or ulcerated mass. This typically occurs in men from the 6th to 8th decades of life, and risk factors include human papillomavirus, phimosis, presence of foreskin and poor hygiene, chronic inflammatory conditions such as lichen sclerosus, trauma, and smoking. Primary urethral malignancies including urothelial carcinoma and adenocarcinoma can occur but may lack this distal predilection. Sarcoma, melanoma, leukemia or lymphoma, and metastatic disease are less common sources of penile malignancy. Because of the sensitive nature of penile malignancies, there may be delays in seeking care and in subsequent diagnosis. Recently, the staging guidelines for penile cancer have been updated concurrently with a shift toward more penile-preserving therapies, which have led to a larger role of imaging in diagnosis, staging, and treatment planning for penile malignancies. A variety of imaging modalities may play a role in the identification and staging of penile malignancy, including an increased use of MRI for local staging of tumors, CT and PET/CT for identification of nodal and distant disease, and US for image-guided biopsy. The authors discuss an imaging approach to a spectrum of penile malignancies, with an emphasis on radiologic and pathologic correlation and how knowledge of normal tissue types and anatomic structures can aid in the diagnosis and staging of these tumors. ^©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Non-human papillomavirus penile squamous cell carcinoma with unusual coral-like polymorphic lesion

Penile cancer is a rare malignancy of the male genital system. Approximately 98% of penile cancer corresponds to squamous cell carcinoma (SCC), with further morphological and molecular classification into human papillomavirus (HPV) dependent and non-HPV SCC. Compared to HPV-induced SCC, non-HPV SCC appeared to have a worse prognosis. Here, we present a case of an uncircumcised male with an unusual coral-like polymorphic lesion, and confirmed histopathology of well-differentiated non-HPV penile SCC with rapid growth progression.

Penile intraepithelial neoplasia: Distribution of subtypes, HPV genotypes and p16INK4a in 84 international cases

There are few pathologic or molecular studies of penile precancerous lesions, and the majority refers to lesions associated with invasive carcinomas. Penile Intraepithelial Neoplasia (PeIN) is classified in two morphologically and distinctive molecular groups, non-HPV and HPV-related with special subtypes. The primary purpose of this international series was to classify PeIN morphologically, detect HPV genotypes and determine their distribution according to PeIN subtypes. A secondary aim was to evaluate the p16^INK4a immunostaining as a possible HPV surrogate for high-risk HPV infection in penile precancerous lesions. Samples consisted of 84 PeIN cases, part of a retrospective cross-sectional analysis of 1095 penile carcinomas designed to estimate the HPV DNA prevalence in penile cancers using PCR and p16^INK4a immunostaining. Penile Intraepithelial Neoplasia (PeIN) was classified in HPV-related (basaloid, warty-basaloid, warty, hybrid, and mixed subtypes) and non-HPV-related (differentiated), the former being the most frequent. PeIN subtypes were differentiated (non-HPV-related) and basaloid, warty-basaloid, warty, hybrid and mixed (HPV-related). Basaloid PeIN was the most commonly diagnosed subtype, and HPV16 was the most frequent HPV genotype detected. Warty-basaloid and warty PeIN showed a more heterogeneous genotypic composition. Most HPV genotypes were high-risk but low-risk HPV genotypes were also present in a few cases (4%). A single HPV genotype was detected in 82% of HPV positive cases. In contrast, multiple genotypes were detected in the remaining 18% of cases. The findings in this study support the paradigm that penile in situ neoplasia, like its invasive counterparts, is HPV dependent or independent and has distinctive morphological subtypes readily identified in routine practice. Considering that HPV16 is clearly the predominant type, and that the three available vaccines have HPV16, all of them will be suitable for vaccination programs; the price of the vaccines will be probably the main determinant to choose the vaccine.

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.

Dermoscopy of genital diseases: a review

The male and female external genital regions are anatomical areas in which various types of skin disorders may occur. Although most of these conditions can be diagnosed by means of clinical examination and an accurate medical history, in most cases further investigations with time-consuming and/or invasive procedures are needed in order to reach the correct diagnosis. Dermoscopy, as a modern non-invasive tool, is able to better diagnose pigmented and non-pigmented skin tumours along with various inflammatory and infectious skin and appendage disorders. The aim of this paper was to provide a review of the use of dermoscopy in genital disorders based on published data and to include personal experience gained from real life, focusing on any possible gender difference and whether disease mucosal/semimucosal dermoscopy features may differ from those observed on the skin. In conclusion, genital dermoscopy should always be considered during clinical inspection in order to enhance the diagnosis or to rule out those conditions that may look similar but that show a different dermoscopy pattern, thus narrowing down the differential diagnoses and avoiding unnecessary invasive investigations.

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.

Comparison of Human Papillomavirus Genotypes in Penile Intraepithelial Neoplasia and Associated Lesions: LCM-PCR Study of 87 Lesions in 8 Patients

Penile intraepithelial neoplasia (PeIN) is currently classified in human papillomavirus (HPV)- and non-HPV-related subtypes with variable HPV genotypes. PeINs are frequently associated with other intraepithelial lesions in the same specimen. The aim of this study was to detect and compare HPV genotypes in PeINs and associated lesions using high-precision laser capture microdissection-polymerase chain reaction and p16^INK4a immunostaining. We evaluated resected penile specimens from 8 patients and identified 33 PeINs and 54 associated lesions. The most common subtype was warty PeIN, followed by warty-basaloid and basaloid PeIN. Associated lesions were classical condylomas (17 cases), atypical classical condylomas (2 cases), flat condylomas (9 cases), atypical flat condylomas (6 cases), flat lesions with mild atypia (12 cases), and squamous hyperplasia (8 cases). After a comparison, identical HPV genotypes were found in PeIN and associated lesions in the majority of the patients (7 of 8 patients). HPV16 was the most common genotype present in both PeIN and corresponding associated lesion (50% of the patients). Nonspecific flat lesions with mild atypia, classical condylomas, and atypical condylomas were the type of associated lesions most commonly related to HPV16. Other high-risk HPV genotypes present in PeIN and associated nonspecific flat lesion with mild atypia were HPV35 and HPV39. In this study of HPV in the microenvironment of penile precancerous lesions, we identified identical high-risk HPV genotypes in PeIN and classical, flat, or atypical condylomas and, specially, in nonspecific flat lesions with mild atypia. It is possible that some of these lesions represent hitherto unrecognized precancerous lesions.

Differentiated-Type Intraepithelial Neoplasia-Like Lesion Associated with Squamous Cell Carcinoma of the Anus: A Case Report with Molecular Profile

Differentiated-type Intraepithelial Neoplasia (DIN) is defined as HPV-negative squamous intraepithelial proliferation with abnormal keratinocyte differentiation and basal cell atypia, originally described in the vulva, with following descriptions in the oral cavity. DIN occurring in the anus is quite rare, and to the best of our knowledge, only one publication reported it. In this report, we describe the clinicopathological features of this entity on anal margin, associated with invasive squamous cell carcinoma. In addition, using the next generation sequencing (NGS) technique, we have demonstrated TP53 mutation in the invasive component but not in the associated DIN-like lesion, where p53 immunohistochemical expression was restricted to basal layers.

Continuous Spatial Sequences of Lichen Sclerosus, Penile Intraepithelial Neoplasia, and Invasive Carcinomas: A Study of 109 Cases

Lichen sclerosus (LSc) with penile cancer is found in about two thirds of specimens. It has been hypothesized that LSc represents a precancerous condition. To qualify as such, in addition to cytological atypia and similarity with the invasive tumor, a spatial correlation between LSc and neoplastic lesions needs to be demonstrated. The purpose of this study was to evaluate such a spatial relationship. Circumcision (28 cases) and penectomy (81 cases) specimens were evaluated. All cases had LSc, penile intraepithelial neoplasia (PeIN), and/or invasive squamous cell carcinomas. We examined LSc in relation to invasive carcinoma, PeIN, and normal epithelia. Invasive squamous cell carcinomas, classified according to the World Health Organization criteria as non–human papillomavirus (HPV)-related and HPV-related PeIN, were present in 100 cases. Non-HPV-related (differentiated) PeIN was the most common subtype associated with LSc (89%). There were 5 spatial patterns identified: (1) LSc adjacent to PeIN (23%), (2) LSc adjacent and comprising PeIN (42%), (3) LSc next to and within invasive carcinomas (8%), (4) LSc throughout the sequence PeIN-invasive carcinoma (24%), and (5) LSc was separate (with normal tissue between the lesions) from PeIN and/or invasive carcinomas in a minority of cases (3%). LSc within the cancer was not previously described. In this series, we found 35 cases with LSc within invasive carcinomas. The striking continuous spatial relationship among LSc, PeIN, and/or invasive carcinoma as shown in this study may be a necessary (but not sufficient) condition for the hypothesis postulating LSc as a penile precancerous lesion.

Dermoscopy of Inflammatory Genital Diseases: Practical Insights

Diagnosis of genital inflammatory disorders may be difficult for several reasons, such as their similar appearance, possible misdiagnosis with infectious and malignant conditions, and peculiar anatomic conditions that may lead to modification of clinical features. Dermoscopy could be included as a part of the clinical inspection of genital diseases to support diagnosis, as well as to ideally avoid unnecessary invasive investigation. Practical guidance for the use of dermoscopy in the assessment of the main inflammatory genital diseases is provided, namely for lichen sclerosus, lichen planus, psoriasis, lichen simplex chronicus, and plasma cell mucositis.

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.

Mixed papillary-sarcomatoid carcinoma of the penis: report of an aggressive subtype

Several different histological subtypes of penile carcinoma had been described in the last decades, many with different biological behavior and prognosis. The association of two histological subtypes (mixed tumors) can be observed in one third of the cases. The most common association is of warty and basaloid tumors, two HPV-related carcinomas. Here, we described a mixed papillary-sarcomatoid carcinoma, never reported before. Although it is a clinical aspect of a low-grade verruciform tumor, its prognosis showed it to be very aggressive due to the sarcomatoid component hidden above the papillary component. The two components showed opposite cadherin/vimentin expression pointed to epithelial-mesenchymal transition between them.

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.

Cutaneous Squamous Cell Carcinoma: Review of the Eighth Edition of the American Joint Committee on Cancer Staging Guidelines, Prognostic Factors, and Histopathologic Variants

Cutaneous squamous cell carcinoma is the second most common form of nonmelanoma skin cancer after basal cell carcinoma and accounts for the majority of nonmelanoma skin cancer-related deaths. In 2017, the American Joint Committee on Cancer revised the staging guidelines of cutaneous squamous cell carcinoma to reflect recent evidence concerning high-risk clinicopathologic features. This update reviews the literature on prognostic features and staging, including the eighth edition of the American Joint Committee on Cancer Staging Manual. A wide range of histopathologic variants of cutaneous squamous cell carcinoma exists, several of which are associated with aggressive behavior. A review of cutaneous squamous cell carcinoma variants, emphasizing diagnostic pitfalls, immuhistochemical findings and prognostic significance, is included. Of note, the eighth edition of the American Joint Committee on Cancer Staging Manual refers to squamous cell carcinoma of the head and neck only.

Pathophysiological basis of human papillomavirus in penile cancer: Key to prevention and delivery of more effective therapies

Answer questions and earn CME/CNE Squamous cell carcinoma (SCC) of the penis is a rare malignancy in the United States, with a significantly higher incidence-up to 20 to 30 times greater-in areas of Africa and South America. This can be explained in part by the significantly greater prevalence of sexually transmitted diseases among high-risk males often having unprotected sex with multiple sexual partners. Human papillomavirus (HPV) has been implicated as the infectious pathway by which several these penile neoplasms originate from precursor lesions. In this regard, a fundamental understanding of HPV in penile carcinogenesis can have meaningful implications in understanding 1) the diagnosis of HPV-related precursor penile lesions, 2) targeting HPV-specific molecular pathways, and 3) cancer prevention. Using vaccination programs not only may improve patient outcomes but also may minimize the need for highly aggressive and often debilitating surgical resection. CA Cancer J Clin 2016;66:481-495. © 2016 American Cancer Society.

Review of in situ and invasive penile squamous cell carcinoma and associated non-neoplastic dermatological conditions

Penile carcinoma is a rare genitourinary malignancy in North America and Europe with highest rates recorded in South America, Africa and Asia. Recent classifications have refined the terminology used in classifying intraepithelial/in situ lesions and additionally newer entities have been recognised in the invasive category. While increasing recognition of a bimodal pathway of penile carcinogenesis has facilitated understanding and classification of these tumours, handling and subtyping of penile malignancies presents a challenge to the reporting pathologist, in part due to their rarity. This article reviews the terminology and classification of in situ and invasive carcinomas and their relationship to human papilloma virus status. In addition, associated non-neoplastic dermatological conditions of relevance and appropriate ancillary investigations will be addressed.

Does the width of the surgical margin of safety or premalignant dermatoses at the negative surgical margin affect outcome in surgically treated penile cancer?

AIMS

To evaluate the prognostic impact of the width of negative surgical margins (NSM) and associated and preinvasive lesions at the NSM in patients with penile squamous cell cancer (PSC).

METHODS

Enrolling 87 patients with NSM who underwent surgery for PSC, the archived margin slides and entirely wax-embedded surgical margins were retrieved from the pathology files. After step sections were cut, margins were stained with antibodies against CK5/6, p16, p53 and Ki-67 and subjected to in situ hybridisation for high-risk human papillomavirus (HPV). All NSM were histologically examined for squamous hyperplasia (SH), lichen sclerosus (LS) and subtypes of penile intraepithelial neoplasia (PeIN). Then, histological findings were correlated with cancer-specific mortality (CSM, median follow-up 34 months; IQR 6-70).

RESULTS

All NSM were negative for high-risk HPV and exhibited SH (p16 and p53 negative, Ki-67 variably positive), LS (p16 negative, variable p53 and Ki-67 positivity) and differentiated PeIN (dPeIN; p16 negative, Ki-67 positive, variable p53 positivity) in 28 (32%), 30 (34%) and 22 (25%) cases, respectively, whereas PeIN subtypes other then dPeIN did not occur. Pathological tumour stage was the only independent predictive parameter with respect to CSM in the multivariable analysis (p=0.001).

CONCLUSIONS

SH, LS and dPeIN are frequent histological findings at the NSM of surgically treated PSC. However, neither the width of the NSM nor dPeIN, LS or SH at the NSM influences prognostic outcome.

Differential gene hypermethylation in genital lichen sclerosus and cancer: a comparative study

AIMS

Lichen sclerosus (LS) is a chronic inflammatory disease of the genital skin of unknown aetiology. The role of LS in penile squamous cell carcinogenesis is not well characterized. HPV has been implicated in both, as have epigenetic changes. The presence of HPV and hypermethylation of the MGMT, p16, RASSF1, RASSF2, TSLC1 and TSP1 genes were studied in penile LS; MGMT, RASSF2 and TSLC1 hypermethylation in penile cancer and TSLC1 hypermethylation in vulvar LS and cancer extends previous results reported by our group.

METHODS AND RESULTS

Thirty-seven HPV genotypes and hypermethylation were evaluated by PCR/reverse-line-blot and methylation-specific PCR respectively, in 27 preputial LS, 24 penile SCC, 30 vulvar SCC, 21 vulvar LS and 22 normal skin cases. HPV66 was present in 3.7% of penile LS cases, and p16 and RASSF2 hypermethylation were more frequent in penile cancer than in penile LS. p16, RASSF1, RASSF2 and TSP1 hypermethylation were similar in penile and vulvar LS.

CONCLUSIONS

Gene hypermethylation is a common event in penile LS, and occurs approximately as frequently as in vulvar LS. Certain genes can be hypermethylated as an early or late event in LS or cancer, respectively. This suggests a possible sequential role for these alterations in the transition from benign to malignant lesions.

Differentiated dysplasia is a frequent precursor or associated lesion in invasive squamous cell carcinoma of the oral cavity and pharynx

The source of precursor lesions of squamous cell carcinoma (SCC) of the oral cavity and pharynx, their classification, and grading are controversial. In contrast, vulvar and penile cancer precursor lesions are known to be related to human papillomavirus or chronic inflammation and can be described using the vulvar intraepithelial neoplasia (VIN) classification system (VIN 1-3) or as differentiated vulvar intraepithelial neoplasia (dVIN), respectively. Oral and pharyngeal SCC precursor lesions are more etiologically diverse, and the spectrum of lesions may thus be wider. No international consensus exists regarding the histological types of precursor lesions or the significance of individual types. We therefore reviewed resection specimens and preceding biopsies of 155 patients with SCC of the oral cavity and pharynx (excluding tonsils) and identified five basic patterns of SCC-associated or precursor lesions: (1) pleomorphic (22/155), (2) basaloid (5/155), (3) differentiated (63/155), (4) mixed (42/155), and (5) verrucous (12/155). Keratinization was a common but variable feature in differentiated, mixed, and verrucous dysplasia. In 11/155 patients, no precursor lesion could be identified. Progression of isolated differentiated dysplasia (ranging from months to years) was documented in 13/155 (8 %) of patients. Our data suggest that full-thickness epithelial dysplasia of pleomorphic or basaloid type is present in <20 % of oral and pharyngeal SCC, and differentiated dysplasia is a frequent precursor or associated in situ lesion. Failure to recognize differentiated dysplasia results in the underdiagnosis of many patients at risk for invasive carcinoma. These results indicate a need to refine criteria to distinguish differentiated dysplasia from morphologically related lichenoid lesions.

Genital lichen sclerosus/balanitis xerotica obliterans in men with penile carcinoma: a critical analysis

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: The European Association of Urology guidelines identify lichen sclerosus (LS) as a strong risk factor for penile squamous cell carcinoma (pSCC). However, this statement is based on the findings of case-control studies (Level of Evidence 2a) and a direct causal relationship between LS/balanitis xerotica obliterans (BXO) and pSCC remains to be established. Firm guidelines with respect to the appropriate follow-up policy for LS/BXO are lacking, whereas the impact of synchronous LS/BXO on the prognosis of pSCC remains to be determined. The presence of histologically-confirmed synchronous LS/BXO in patients diagnosed with pSCC is relatively high, although it is not associated with an increased risk of adverse histopathological features. LS/BXO can develop in extragenital skin grafts used for reconstruction after organ-sparing surgery for pSCC.

OBJECTIVES

To determine the rate of lichen sclerosus/balanitis xerotica obliterans (LS/BXO) in patients with penile squamous cell carcinoma (pSCC) and establish whether the presence of LS/BXO is associated with adverse histopathological features of pSCC. To report the phenomenon of LS involving non-genital skin grafts in patients who underwent organ-sparing surgery and split-skin graft (SSG) reconstruction

PATIENTS AND METHODS

Between January 2002 and January 2010, 223 men underwent surgical treatment for pSCC. A group of 52 patients with histologically-confirmed synchronous LS was identified (group A; overall rate of LS/BXO = 23.3%) and compared with a group of patients without synchronous LS (group B; n = 171; 76.7%). A subgroup of patients who underwent surgical excision and SSG reconstruction was also identified The histology reports of graft biopsies obtained during follow-up were reviewed and the rate of LS involving the graft was also recorded.

RESULTS

Mean (range) age at diagnosis was 60.9 (34-81) years and 60.7 (28-89) years for groups A and B, respectively (P = 0.958). The mean (range) duration of follow-up was 38.3 (4-92) months for group A and 45.5 (4-107) months for group B (P = 0.162) No statistically significant differences were noted between groups A and B in terms of tumour grade (P = 0.091), stage (P = 0.697), presence of lymphovascular invasion (P = 0.333), histological subtype (P = 0.107), associated carcinoma in situ (P = 0.246) or nodal status at initial diagnosis (P = 0.555). In the subgroup of 188 patients who underwent SSG reconstruction, 41 (21.8%) patients had histologically-confirmed synchronous LS; in this subgroup, 26 (13.8%) patients underwent graft biopsy during follow-up. Genital LS involving the graft was identified in seven specimens, although none of these seven cases had associated recurrent pSCC.

CONCLUSIONS

The presence of histologically-confirmed synchronous LS in patients with pSCC is relatively high but is not associated with increased rates of adverse histopathological features, including carcinoma in situ. LS can develop in extragenital skin grafts, although its association with the long-term risk for recurrent pSCC is not apparent in the present study.

Male genital premalignant dermatoses

The spectrum of conditions affecting the penile skin is varied and ranges from simple, benign dermatoses to premalignant and malignant conditions. Recently, improved understanding of the aetiology and natural history of these conditions has shaped new treatment paradigms and a functional knowledge of dermatology, urology and genitourinary medicine is required to successfully diagnose and treat these men. In this article, we explore the common precancerous states that can lead to penile carcinoma and review the recent advances with regards to the molecular basis for these dermatoses and the treatments that may be most effective for these men.

Advances in the pathology of penile carcinomas

The incidence of penile cancer varies from country to country, with the highest figures reported for countries in Africa, South America, and Asia and lowest in the United States and Europe. Causes of this variation are not clear, but they are thought to be related to human papillomavirus infection, smoking, lack of circumcision, chronic inflammation, and poor genital hygiene. Most penile tumors are squamous cell carcinomas, and a variegated spectrum of distinct morphologies is currently recognized. Each one of these subtypes has distinctive pathologic and clinical features. About half of penile carcinomas are usual squamous cell carcinomas, and the rest corresponds to verrucous, warty, basaloid, warty-basaloid, papillary, pseudohyperplastic, pseudoglandular, adenosquamous, sarcomatoid, and cuniculatum carcinomas. Previous studies have found a consistent association of tumor cell morphology and human papillomavirus presence in penile carcinomas. Those tumors composed of small- to intermediate-sized, basaloid ("blue") cells are often human papillomavirus positive, whereas human papillomavirus prevalence is lower in tumors showing large, keratinizing, maturing eosinophilic ("pink") cells. Human papillomavirus-related tumors affect younger patients, whereas human papillomavirus-unrelated tumors are seen in older patients with phimosis, lichen sclerosus, or squamous hyperplasia. This morphologic distinctiveness is also observed in penile intraepithelial neoplasia. The specific aim of this review is to provide a detailed discussion on the macroscopic and microscopic features of all major subtypes of penile cancer. We also discuss the role of pathologic features in the prognosis of penile cancer, the characteristics of penile precursor lesions, and the use of immunohistochemistry for the diagnosis of invasive and precursor lesions.