Vulvar Acanthosis With Altered Differentiation

Differentiated Vulvar Intraepithelial Neoplasia: A Brief Review of Clinicopathologic Features

Differentiated-type vulvar intraepithelial neoplasia (dVIN) is a non–human papilloma virus (HPV)-related precursor lesion to vulvar squamous carcinoma. The terminology has only become recognized clinically and histopathologically in recent years despite being described more than 50 years ago. As opposed to the HPV-related VIN (uVIN), dVIN has different features of histomorphology, risk of progression, and molecular pathogenesis. Notably, dVIN commonly develops in a background of chronic inflammatory dermatoses such as lichen sclerosis and lichen simplex chronicus. The recognition of dVIN remains a challenge owing to lack of accurate and reproducible diagnostic criteria. Morphologically, basal layer atypia, dyskeratosis, and elongation and anastomosis of the rete ridges are regarded as very useful diagnostic features. Ancillary tests can be very helpful to establish a definitive diagnosis in some ambiguous cases. In contrast to uVIN, dVIN is more likely to progress to vulvar squamous carcinoma in a shorter period. The goal of this review is to elaborate on the clinicopathologic characteristics and underline the key histologic features that best facilitate the diagnosis of dVIN.

Classic and Hypertrophic Vulvar Lichen Planus

OBJECTIVES

Three types of lichen planus (LP) occur on the vulva: erosive, classic, and hypertrophic. The latter 2 occur on keratinized skin and little is known about their clinicopathologic appearance.

MATERIALS AND METHODS

Vulvar biopsies of keratinized skin reported as LP or "lichenoid" between 2011 and 2017 were reviewed. Inclusion required age of older than 18 years, a lichenoid tissue reaction, and insufficient abnormal dermal collagen to diagnose lichen sclerosus. Clinical and histopathologic data were collected and cases were categorized as hypertrophic, classic, or nonspecific lichenoid dermatosis. Descriptive statistics were performed and groups were compared with the Fisher exact test.

RESULTS

Sixty-three cases met criteria for inclusion. Twenty-nine (46%) cases were categorized as hypertrophic LP, 21 (33%) as classic LP, and 13 (21%) as nonspecific lichenoid dermatosis. There were no significant differences in age, primary symptom, biopsy location, or duration of disease between the 3 groups. When compared with classic and nonspecific disease, hypertrophic LP was less likely to have comorbid dermatoses and more likely to be red, diffuse, have scale crust, and contain plasma cells in the infiltrate. Nonspecific disease had similar clinical features to classic LP but was less likely than the other 2 categories to have a dense lymphocytic infiltrate and exocytosis.

CONCLUSIONS

Vulvar LP on keratinized skin has a diversity of appearances and presents a clinicopathologic challenge. Further research is required to understand the natural history of hypertrophic LP and the underlying diagnosis of nonspecific lichenoid cases.

Is Vulvovaginal Lichen Planus Associated With Squamous Cell Carcinoma?

Objective

The aim of the study was to assess for the presence of vulvar lichen planus (LP) in association with human papillomavirus (HPV)–independent squamous cell carcinoma (SCC).

Materials and Methods

We performed a clinicohistopathologic review of consecutive vulvectomies and wide local excisions for HPV-independent vulvar or vaginal SCC from 2007 to 2017. Data collected included site of SCC, adjacent precursor lesions and dermatoses, dermatologic treatment, and outcome.

Results

There were 43 cases of primary HPV-independent vulvar SCC treated by excision, but no vaginal cancers. Eighteen women (42%) had a preoperative diagnosis of lichen sclerosus (LS); none had a diagnosis of LP. Topical corticosteroids were prescribed in 19 (44%) of 43, with 4 women placed on maintenance therapy. Tumors arose from the labia minora, labia majora, and periclitoris, but not from vestibule or perianus. On histopathological review, LS was present in 41 (95%) of 43 specimens, 1 had a nonspecific lichenoid reaction, and 1 had lichen simplex; both of the latter had subsequent biopsies showing LS. Lichen planus was not seen in association with SCC. Differentiated vulvar intraepithelial neoplasia (dVIN) was present in 38 (88%) of 43 specimens, whereas 1 had acanthosis with altered differentiation and 4 (9%) had no precursor lesion. Differentiated vulvar intraepithelial neoplasia had standard, basaloid, and hypertrophic morphology, superficially resembling erosive LP in 9 (24%) of 38 and hypertrophic LP in 6 (16%) of 38.

Conclusions

Lichen planus was not seen in association with HPV-independent vulvar SCC, whereas LS was underrecognized and inadequately treated in this group. Pathologists should be aware that dVIN may superficially resemble erosive or hypertrophic LP.

Verruciform and Condyloma-like Squamous Proliferations in the Anogenital Region

CONTEXT.—

Histologic distinction between condyloma acuminatum and various benign and malignant condyloma-like lesions in the anogenital area poses a common diagnostic challenge to pathologists across subspecialties.

OBJECTIVE.—

To review the overlapping and distinguishing features of condyloma acuminatum and its mimics, and to clarify confusing terminology and diagnostic criteria for problematic entities.

DATA SOURCES.—

A review of the literature on condyloma acuminatum (ordinary and giant types), verrucous carcinoma, warty/warty-basaloid high-grade squamous intraepithelial lesion and squamous cell carcinoma, papillary squamous cell carcinoma, bowenoid papulosis, verruca vulgaris, epidermolytic acanthoma, and verruciform xanthoma was performed.

CONCLUSIONS.—

Correct diagnosis of condyloma acuminatum and condyloma-like lesions has important clinical implication and entails familiarization with their clinical presentations and histopathologic features. Contrary to historical belief, giant condyloma acuminatum and verrucous carcinoma should be considered distinct entities based on different pathogenetic pathways. Ancillary tools available for identifying and genotyping human papillomavirus can aid in diagnosis when histopathologic findings are inconclusive. Recognition of relatively rare entities such as bowenoid papulosis, epidermolytic acanthoma, and verruciform xanthoma would avoid overdiagnosis and unnecessary, overaggressive treatment.

Genomic Characterization of Vulvar (Pre)cancers Identifies Distinct Molecular Subtypes with Prognostic Significance

Purpose: Vulvar cancer (VC) can be subclassified by human papillomavirus (HPV) status. HPV-negative VCs frequently harbor TP53 mutations; however, in-depth analysis of other potential molecular genetic alterations is lacking. We comprehensively assessed somatic mutations in a large series of vulvar (pre)cancers.Experimental Design: We performed targeted next-generation sequencing (17 genes), p53 immunohistochemistry and HPV testing on 36 VC and 82 precursors (sequencing cohort). Subsequently, the prognostic significance of the three subtypes identified in the sequencing cohort was assessed in a series of 236 VC patients (follow-up cohort).Results: Frequent recurrent mutations were identified in HPV-negative vulvar (pre)cancers in TP53 (42% and 68%), NOTCH1 (28% and 41%), and HRAS (20% and 31%). Mutation frequency in HPV-positive vulvar (pre)cancers was significantly lower (P = 0.001). Furthermore, a substantial subset of the HPV-negative precursors (35/60, 58.3%) and VC (10/29, 34.5%) were TP53 wild-type (wt), suggesting a third, not-previously described, molecular subtype. Clinical outcomes in the three different subtypes (HPV⁺, HPV^-/p53wt, HPV^-/p53abn) were evaluated in a follow-up cohort consisting of 236 VC patients. Local recurrence rate was 5.3% for HPV⁺, 16.3% for HPV^-/p53wt and 22.6% for HPV^-/p53abn tumors (P = 0.044). HPV positivity remained an independent prognostic factor for favorable outcome in the multivariable analysis (P = 0.020).Conclusions: HPV^- and HPV⁺ vulvar (pre)cancers display striking differences in somatic mutation patterns. HPV^-/p53wt VC appear to be a distinct clinicopathologic subgroup with frequent NOTCH1 mutations. HPV⁺ VC have a significantly lower local recurrence rate, independent of clinicopathological variables, opening opportunities for reducing overtreatment in VC. Clin Cancer Res; 23(22); 6781-9. ©2017 AACR.

Differentiated exophytic vulvar intraepithelial lesions are genetically distinct from keratinizing squamous cell carcinomas and contain mutations in PIK3CA

Human papillomavirus-negative keratinizing vulvar cancers typically harbor TP53 mutations as do their precursors, differentiated vulvar intraepithelial neoplasia. However, atypical verruciform proliferations are also associated with these malignancies and their pathogenesis is poorly understood. This study compared 11 atypical verruciform lesions, including atypical verruciform hyperplasia, vulvar acanthosis with altered differentiation, and verruciform lichen simplex chronicus, with 14 human papillomavirus-negative keratinizing squamous cell carcinomas. Extracted tissue DNA was subjected to targeted massively parallel sequencing of the exonic regions of 300 genes. Eight (73%) and six (55%) of eleven atypical verruciform lesions contained mutations in PIK3CA and ARID2, respectively. No TP53 mutations were identified. Eleven (79%) and five (36%) of fourteen keratinizing squamous cell carcinomas tested contained TP53 and CDKN2A mutations, respectively. Keratinizing squamous cell carcinomas displayed the majority of copy number variations with some variations (7p gain and 8p loss) shared by some cases in both groups. One patient developed atypical verruciform lesions with PIK3CA mutations followed by a keratinizing carcinoma with mutations in both PIK3CA and TP53. This study, for the first time segregates atypical verruciform lesions by virtue of a unique genotype (PIK3CA mutant/TP53 wild type) illustrating an example of progression to a TP53-mutated keratinizing carcinoma. The findings indicate that although PIK3CA mutations are found in <10% of vulvar squamous cell carcinomas, they may be specific for a particular pathway involving atypical verruciform lesions, which could function as either a direct precursor or a risk factor for vulvar squamous cell carcinoma. Given the presence of a molecular signature, we propose the term 'differentiated exophytic vulvar intraepithelial lesion' for this group. Whether they function as direct precursors to a less common form of squamous cell carcinoma will require further study, but carcinomas associated with these lesions might warrant testing for PIK3CA mutations to address this question.

Squamous precursor lesions of the vulva: current classification and diagnostic challenges

Growing evidence has established two major types of vulvar intraepithelial neoplasia (VIN), which correspond to two distinct oncogenic pathways to vulvar squamous cell carcinoma (VSCC). While the incidence of VSCC has remained relatively stable over the last three decades, the incidence of VIN has increased. VIN of usual type (uVIN) is human papillomavirus (HPV)-driven, affects younger women and is a multicentric disease. In contrast, VIN of differentiated type (dVIN) occurs in post-menopausal women and develops independent of HPV infection. dVIN often arises in a background of lichen sclerosus and chronic inflammatory dermatoses. Although isolated dVIN is significantly less common than uVIN, dVIN bears a greater risk for malignant transformation to VSCC and progresses over a shorter time interval. On histological examination, uVIN displays conspicuous architectural and cytological abnormalities, while the morphological features that characterise dVIN are much more subtle and raise a wide differential diagnosis. On the molecular level, dVIN is characterised by a higher number of somatic mutations, particularly in TP53. Here we review the classification, epidemiology, clinical features, histomorphology, ancillary markers and molecular genetics of both types of VIN, and discuss the morphological challenges faced by pathologists in interpreting these 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.

Comprehensive analysis of human papillomavirus prevalence and the potential role of low-risk types in verrucous carcinoma

The role of human papillomavirus (HPV) infections in the development of verrucous carcinoma, a well-differentiated variant of squamous cell carcinoma with difficult differential diagnosis, is controversial in the literature. In this study, we analysed verrucous carcinoma from different origins for the presence and activity of a broad spectrum of HPV types, and carefully reviewed the histopathological features. A random series of 27 formalin-fixed, paraffin-embedded specimens of verrucous carcinoma was taken, representing the head and neck region (n=6), anogenital area (n=16) and extragenital skin region (n=5). After review of the histological slides, all samples were subjected to different polymerase chain reaction-based HPV detection techniques, together detecting a total of 83 HPV types, including both mucosal and cutaneous types. Histological revision was carefully performed. Lesions with keratinised papillae, blunt stromal invaginations and minimal cytological atypia were considered verrucous carcinoma. Condylomatous lesions with viral changes were defined as giant condyloma. Verrucous lesions that did not meet those criteria were classified as verrucous hyperplasia. Tumours with stromal infiltration were considered as invasive squamous cell carcinoma. Histological revision revealed that 13 out of 27 cases were verrucous carcinoma (one showing a double infection with HPV 35 and 45), 5 invasive squamous cell carcinomas, 5 verrucous hyperplasia (one with a double infection with HPV 4 and 8), 1 pseudoepitheliomatous hyperplasia and 3 giant condylomas. All three giant condylomas were low-risk HPV positive (HPV 6 and 11) and showed active mRNA transcription. None of the HPV-positive samples tested positive for diffuse p16(INK4A) staining. In conclusion, our results do not support a causal role of HPV in the development of verrucous carcinoma. Testing for LR-HPV, particularly HPV 6 and 11, may help in the differential diagnosis of lesions suspicious of verrucous carcinoma as those testing positive for LR-HPV most likely represent giant condylomas.

Pathology of Vulvar Neoplasms

Carcinoma of the vulva is an uncommon malignant neoplasm (approximately one-fifth as frequent as cervical cancer) and represents 4% of all genital cancers in women. Approximately two-thirds of cases occur in women older than 60 years, and squamous cell carcinoma is the most common histologic type. Several different subtypes of squamous cell carcinoma have been described in the vulva; however, in terms of etiology, pathogenesis, and histologic features, most carcinomas belong to one of two categories: keratinizing squamous cell carcinomas associated with chronic inflammatory skin disorders, and basaloid or warty carcinomas related to infection with high oncogenic risk human papillomaviruses. Glandular neoplasms of the vulva arise from the vulvar apocrine sweat glands (papillary hidradenoma and Paget disease) or the Bartholin gland and their cause is not known.

Giant condyloma versus verrucous carcinoma: a case report

Giant condyloma acuminatum is a large, slow-growing, exophytic, cauliflower-like tumor of the external genitalia. It is a histologically benign lesion, largely associated with human papillomavirus infection but with a high recurrence rate. The main differential diagnosis includes verrucous carcinoma. Differentiation between these 2 types of tumors is important with respect to treatment and prognosis. We present a case report of a 26-year-old woman with giant condyloma acuminata of the vulva and discuss the histological features and treatment modalities of this condition.

Genital verrucous carcinoma is associated with lichen sclerosus: a retrospective study and review of the literature

BACKGROUND

The association of lichen sclerosus (LS) with genital squamous cell carcinoma is well recognized. However, the relationship between LS and verrucous carcinoma remains unclear.

OBJECTIVE

To evaluate the associations of genital and perianal verrucous carcinomas with LS.

METHODS

We conducted a retrospective study on patients with a genital or perianal verrucous carcinoma and reviewed their histopathology specimens and clinical notes. We also conducted a literature review.

RESULTS

We identified a total of 13 patients (including 6 women and 7 men) with a genital or perianal verrucous carcinoma. All 5 women with vulval verrucous carcinoma had coexisting LS (5/5), and 1 man with penile verrucous carcinoma had coexisting LS (1/3). In contrast, no coexisting LS was found in all 5 cases of perianal verrucous carcinoma (0/5). Half of the cases of verrucous carcinoma with coexisting LS had recurrences (3/6), while no recurrences were found in those without coexisting LS (0/7).

CONCLUSIONS

Our study and review of the literature demonstrate that vulval verrucous carcinoma is strongly associated with LS. In contrast, perianal verrucous carcinoma is not associated with LS. When genital verrucous carcinoma is diagnosed, it is important to consider LS as a potential concomitant diagnosis and offer appropriate treatments and close follow-up to detect recurrence of verrucous carcinoma.

Human papillomavirus type-distribution in vulvar and vaginal cancers and their associated precursors

OBJECTIVE

Data on human papillomavirus (HPV) prevalence in vulvar and vaginal cancers are limited. These data are important to predict the potential future effect of prophylactic HPV vaccines. Our aim was to conduct a systematic review of HPV type distribution in vulvar and vaginal invasive carcinomas, vulvar intraepithelial neoplasia (VIN), and vaginal intraepithelial neoplasia.

DATA SOURCES

A MEDLINE search was conducted using the terms vulvar/vaginal cancer, intraepithelial neoplasia, and HPV/human papillomavirus through September 2007 with no specified start date or language restrictions.

METHODS OF STUDY SELECTION

A total of 725 abstracts (564 vulvar, 161 vaginal) were reviewed, of which 67 studies (56 vulvar, 11 vaginal) met the inclusion criteria of using polymerase chain reaction (PCR) or hybrid capture assays for HPV DNA detection and having more than one case with HPV data available.

TABULATION, INTEGRATION AND RESULTS

This review identified 2,790 vulvar (1,379 invasive, 1,340 VIN2/3, 71 VIN1) and 315 vaginal cases (83 invasive, 166 vaginal intraepithelial neoplasia 2/3, 66 vaginal intraepithelial neoplasia 1). Most cases were from North America and Europe (87.2%), with few from Asia (5.5%) and South America (7.3%). Human papillomavirus prevalence in vulvar cancer, VIN2/3, and VIN1 was 40.1%, 80.4%, and 77.5%, respectively. HPV prevalence in vaginal cancer, vaginal intraepithelial neoplasia (VAIN)2/3, and VAIN1 was relatively higher at 65.5%, 92.6%, and 98.5%, respectively. HPV16 was the most common type in vulvar (29.3%) and vaginal (55.4%) cancers, VIN2/3 (71.2%) and VAIN2/3 (65.8%).

CONCLUSION

Human papillomavirus prevalence was higher among vaginal than vulvar cases, and HPV16 accounted for most HPV-positive cases for both cancers. Although the potential effect of HPV vaccines on these gynecologic cancers may not be as high as for cervical cancer due to their more diverse causes, vaccinating young women against HPV16/18 may help to reduce the incidence of HPV-related cases.

Systematic review of human papillomavirus prevalence in invasive penile cancer

OBJECTIVE

Type-specific prevalence data of human papillomavirus (HPV) DNA in penile carcinoma are needed to determine the potential impact of HPV prophylactic vaccines, assuming demonstrated efficacy in men.

METHODS

A review was conducted using search terms including HPV and penile cancer. Studies using polymerase chain reaction (PCR) assays for HPV DNA detection in invasive penile carcinoma were included.

RESULTS

A total of 1,266 squamous cell carcinoma (SCC) cases contributed data from 30 studies. The number of SCC was similar in Europe (28.2%), North America (27.6%), South America (23.9%) and Asia (20.4%). All SCC were histologically confirmed with biopsies for DNA detection. Most commonly used PCR primers were type-specific (35.2%), and combination PCR (18.2%). HPV prevalence was 47.9%, ranging from 22.4% in verrucous SCC to 66.3% for the basaloid/warty subtypes. HPV16 (30.8%), HPV6 (6.7%) and HPV18 (6.6%) were the most prevalent types. HPV16 and/or HPV 18 prevalence was 36.7%.

CONCLUSIONS

HPV DNA was detected in half of SCC, with HPV16 being the most common type. If proven efficacious in men, prophylactic vaccines targeting carcinogenic types HPV16 and 18 could potentially reduce approximately one-third of incident SCC.

Prevalence of mucosal and cutaneous human papillomaviruses in different histologic subtypes of vulvar carcinoma

Two independent pathways of vulvar carcinogenesis have currently been identified, one related to infection with mucosal human papillomaviruses (HPVs) and a second related to chronic inflammatory or autoimmune processes. The goal of the study was to examine a possible role of cutaneous HPVs from the beta genus in vulvar carcinogenesis and to evaluate the distribution of intratypic variants of HPV 16 in HPV 16-positive vulvar cancer. Consecutive cases of vulvar carcinoma were retrieved from the files and included the following histologic subtypes: keratinizing (n=21), basaloid (n=7), warty (n=1), mixed basaloid-warty (n=4), verrucous (n=4), keratoacanthoma (n=1), basal cell carcinoma (n=1). All tumors were microdissected and tested for 25 beta HPV types and 25 mucosal HPV types. Cases identified as positive for HPV 16 were further tested for intratypic variants. All cases were immunostained for p16INK4a. Beta HPVs were not detected in any of the tumor cases. Mucosal HPVs were detected in all but one basaloid/warty carcinomas; of these, nine cases (82%) were positive for HPV 16, including five European subtypes, one African subtype, one North American subtype and two indeterminate subtypes. Two of four verrucous carcinomas were positive for HPV 6. Mucosal HPVs were not detected in keratinizing carcinomas, keratoacanthoma and basal cell carcinoma. All cases of basaloid/warty carcinomas, but none of the remaining tumors, overexpressed p16INK4a protein. Our data do not support a role of beta HPVs in the pathogenesis of vulvar carcinoma. The study reaffirms the role of mucosal HPVs, in particular that of HPV 16, in the pathogenesis of basaloid and warty tumor subtypes. The HPV 16 intratypic variation showed correlation with patients' ethnic background. P16INK4a immunostaining seems to be a sensitive and specific marker of vulvar carcinomas positive for oncogenic mucosal HPVs.

Review of Terminology of Precursors of Vulvar Squamous Cell Carcinoma

The popular term for vulvar squamous cell carcinoma in situ/dysplasia is vulvar intraepithelial neoplasia (VIN). VIN is a histological diagnosis based on loss of squamous epithelial maturation associated with enlarged, hyperchromatic, pleomorphic nuclei and increased, usually atypical mitoses. There are two types of VIN: the usual (not otherwise specified) type, also known as warty-basaloid, and the differentiated type. There are 3 grading systems for warty-basaloid VIN: the traditional 3-grade system of VIN 1-3, a low-grade/high grade Bethesda-like system and the International Society for the Study of Vulvovaginal Disease's proposal for only 1 grade. The ISSVD system eliminates VIN 1 and combines VIN 2 and 3 on the grounds that VIN 1 has not been shown to be a reproducible diagnosis and VIN 2 and 3 are not reliably separated. The evidence supports the ISSVD proposal. Warty basaloid VIN may be sub-typed into warty and basaloid VIN. Sub-typing has clinical relevance but its reproducibility is not proven. Warty-basaloid VIN may regress. Differentiated VIN has been typically diagnosed co-incident with squamous cell carcinoma. With increased frequency of performance of biopsy of hyperplastic lesions, differentiated VIN should be diagnosed more commonly before squamous carcinoma occurs.

Concepts in gynaecological pathology: recent advances and their clinical relevance

This is a review of the surgical pathology of the neoplastic and preneoplastic conditions of the female genital tract as well as the secondary Mullerian system. The review is aimed at discussion of entities and concepts that affect prognosis and patient management.