Immunohistochemical Staining for p16 and p53 in Premalignant and Malignant Epithelial Lesions of the Vulva

Correlation of histopathologic findings with clinical predictors of disease recurrence and progression to vulvar carcinoma in patients with differentiated vulvar intraepithelial neoplasia (dVIN)

Objective

To evaluate predictors of recurrence and the risk of progression to carcinoma in patients with dVIN.

Methods

36 self-identified White patients with dVIN from 2011 to 2022 were identified. Demographics, treatment and clinical course were abstracted. Histopathologic features and IHC stains were reviewed by 2 subspecialty pathologists. Standard statistical analyses were applied.

Results

Median cohort age was 70 years (range 39-91). Median follow-up was 29.5 months (range 1-123). All patients were Caucasian. 67% had lichen sclerosus (LS) adjacent to dVIN. 56% of patients had recurrent dVIN a median of 11 months from diagnosis. 14 patients had invasive squamous cell carcinoma of the vulva (SCCV) during the study period: 9 (25%) with synchronous dVIN, 5 (14%) developed SCCV after a median of 21.5 months (range 8-57). Patients treated with surgery were more likely to have recurrent/persistent dVIN (p = 0.04) and synchronous or progression to SCCV (p = 0.02) than patients treated with topical therapy. Excluding 9 women with synchronous SCCV, no initial treatment (observation, topical therapy, surgery) was superior at preventing recurrent/ progressive disease in isolated dVIN. Mutation-type p53 expression was identified in 18 (64%) and aberrant GATA3 staining/expression in 20 (56%) of cases. Aberrant GATA3 expression was associated with a higher frequency of synchronous/progression to SCCV (p < 0.05).

Conclusion

dVIN has an aggressive clinical course in white patients with a high risk of recurrence/persistence and synchronous/progression to SCCV despite treatment. Close surveillance with a low threshold for additional biopsies is warranted. P53 and GATA3 IHC stains may be useful markers of disease outcome.

Alpha, Beta, and Gamma Human Papillomaviruses in Genital Lichen Sclerosus: A Retrospective Cross-Sectional Study

BACKGROUND

Lichen sclerosus (LS) is an inflammatory disease mostly arising at the genital level. It is unclear whether human papillomaviruses (HPVs) have an etiological significance in LS, and data on their prevalence in patients with LS are controversial.

OBJECTIVES

The authors assessed alpha, beta, and gamma HPV prevalence in patients with genital LS. The association of HPV positivity with demographic and clinical factors was also investigated.

METHODS

One hundred thirty-two formalin-fixed, paraffin-embedded LS samples (2016-2020) were retrieved from the archives of a pathology department. Alpha HPVs were genotyped with the INNO-LiPA HPV Genotyping Extra II kit. Beta and gamma HPVs were searched by multiplex Polymerase Chain Reaction. Immunostaining for p16 INK4a was performed on high-risk HPV-positive samples.

RESULTS

Patients had a median age of 61 years, were mostly women ( n = 73, 55.3%), and with an early disease stage ( n = 79, 59.8%). Alpha HPVs were detected in 12/132 cases (9.1%). Among the 5 high-risk HPV-positive cases, only 2 displayed a strong and diffuse p16 INK4a staining. Beta genus was the most prevalent (35/132, 26.5%) and HPV5 was the most frequent beta genotype (25/132, 18.9%). There were 3 gamma HPV-positive cases among those with a valid result (3/131, 2.3%). Multiple infections with genotypes belonging to different genera were infrequent (3/131, 2.3%). No significant differences in the prevalence of the individual genera were observed according to sex and disease stage.

CONCLUSIONS

Of the 3 HPV genera, beta genus showed the highest prevalence. Further research is needed to clarify whether the presence of beta HPVs in genital LS has a clinical significance.

Vulvar squamous cell carcinoma arising on human papillomavirus-independent precursors mimicking high-grade squamous intra-epithelial lesion: a distinct and highly recurrent subtype of vulvar cancer

AIMS

Each category of vulvar squamous cell carcinoma (VSCC), human papillomavirus (HPV)-associated and HPV-independent, arises on a specific intra-epithelial precursor: high-grade squamous intra-epithelial lesions (HSIL) and differentiated vulvar intra-epithelial neoplasia (dVIN), respectively. However, a subset of HPV-independent VSCC arises on an intra-epithelial precursor closely mimicking HSIL. We aimed to explore the clinicopathological features of the HPV-independent tumours with HSIL-like lesions and compare them with HPV-independent VSCC with dVIN and HPV-associated tumours with HSIL.

METHODS AND RESULTS

We retrospectively identified 105 cases of surgically treated VSCC with adjacent intra-epithelial precursors. The cases were classified into three groups based on the HPV status and the adjacent precursor identified: (i) HPV-associated VSCC with HSIL (n = 26), (ii) HPV-independent VSCC with dVIN lesions (n = 54) and (iii) HPV-independent VSCC with HSIL-like lesions (n = 25). We analysed the histological and clinical features including the recurrence-free survival and disease-specific survival in the three groups. Patients with HPV-independent VSCC with HSIL-like lesions and with dVIN were older than patients with HPV-associated VSCC (76 and 77 versus 66 years, respectively, P < 0.001). HPV-independent VSCC with HSIL-like lesions recurred more frequently [hazard ratio (HR) = 3.87; P < 0.001] than HPV-independent VSCC with dVIN (HR = 2.27; P = 0.1) and HPV-associated VSCC (HR = 1). In the multivariate analysis, HPV-independent VSCC with HSIL-like lesions remained significant for recurrence. No differences in disease-specific survival were observed between the three groups.

CONCLUSIONS

Even though VSCC with HSIL-like lesions are not associated with higher mortality, they are more likely to recur and might benefit from more intensive treatment strategies and closer surveillance after treatment.

Molecular Features of Preinvasive and Invasive Vulvar Neoplasms

OBJECTIVES

Neoplasms arising from the vulva are uncommon and comprise various subtypes. Given the recent advancements in the molecular aspects of oncologic pathology and how they have impacted cancer treatment, an understanding of recent innovations in the molecular features of vulvar lesions is important.

MATERIALS AND METHODS

Systematic literature search was performed on PubMed, Google Scholar, and Scopus databases for molecular and genetic characteristics of vulvar neoplasms. Peer-reviewed literature published in English is included.

RESULTS

Squamous cell carcinoma (SCC) and its precursors are the predominant neoplasm at this site. Human papillomavirus (HPV) plays a crucial role in the pathogenesis of some of these lesions. Human papillomavirus-associated SCC follows the carcinogenic pathway driven by viral proteins E6 and E7 while HPV-independent SCC shows a high incidence of mutation of TP53 and CDKN2A genes. Mutations in the genes involving the PI3K-Akt pathway play an important role in the pathogenesis of both types of SCC. Among other vulvar malignancies, melanoma, and vulvar Paget disease (VPD) pose a significant clinical challenge and have unique molecular characteristics. Compared with dermal cutaneous melanoma, vulvar melanoma shows a higher rate of mutation of cKIT and NRAS genes and a lower rate of mutations in BRAF . Less than 20% of VPD shows amplification of ERBB2 and seldom shows mutation in genes involving the PI3K-Akt pathway.

CONCLUSIONS

Several potentially targetable molecular pathways have emerged as they have been shown to be involved in the tumorigenesis of SCC, melanoma, and VPD.

A Comprehensive Discussion in Vaginal Cancer Based on Mechanisms, Treatments, Risk Factors and Prevention

Vaginal cancer is a rare and uncommon disease that is rarely discussed. Although vaginal cancer traditionally occurs in older postmenopausal women, the incidence of high-risk human papillomavirus (HPV)-induced cancers is increasing in younger women. Cervical cancer cells contain high-risk human papillomavirus (HPV) E6 and E7 proteins and inhibiting HPV gene expression leads the cells to stop proliferating and enter senescence. As E6, and E7 protein promoted the carcinogenesis mechanism, and here not only regulate the cellular degradation of P53, and pRb but also enhances the cell proliferation along with E6 protein targets the p53 for breakdown and subsequently promote the apoptotic cell death, and DNA repair inhibition, that is indispensable to the continue the lifecycle of the HPV. As a synchronous or metachronous tumor, vaginal cancer is frequently found in combination with cervical cancer. It is uncertain what causes invasive female vaginal organ cancer. HPV type 16 is the most often isolated HPV type in female vaginal organ cancers. Due to cancer’s rarity, case studies have provided the majority of etiologic findings. Many findings demonstrate that ring pessaries, chronic vaginitis, sexual behavior, birth trauma, obesity, vaginal chemical exposure, and viruses are all risk factors. Because of insufficient understanding and disease findings, we are trying to find the disease’s mechanism with the available data. We also address different risk factors, therapy at various stages, diagnosis, and management of vaginal cancer in this review.

Vulvar Basal Cell Carcinoma: Clinical and Histopathologic Features

Basal cell carcinoma (BCC) is the most frequent skin cancer but <1% of the cases develop in the vulva. Histoprognostic features of vulvar BCCs are not recognized and, consequently, the treatment of the disease is not well codified. To overcome this lack of knowledge, we have performed a retrospective analysis of vulvar BBCs to assess the value of various histological features regarding the disease outcome. In all, 19 patients surgically treated for a vulvar BCC in the Centre Hospitalier Intercommunal de Créteil from March 1, 2000 to September 26, 2019 were retrieved. Clinical and histologic features were reviewed in all cases and analyzed in comparison with disease recurrence and patient's survival. The median age of the patients was 74 (range 54-99) yr. Tumor location on the labium majus was the most frequent (68%). None presented with a medical condition related to BCC. All the patients were treated by surgery alone, except one who benefited from additional radiotherapy. We found a significant association between tumor size and recurrences (P=0.031). Other features associated with disease outcome were tumor thickness, treatment type, and surgical margins. Recurrence was observed for tumors larger than 20 mm with a surgical margin of less than 3 mm. A combination of tumor size, thickness, and surgical margin are histoprognostic factors more significant than tumor subtype.

Vulvar Intraepithelial Neoplasia: A Review of the Disease and Current Management

Importance

Vulvar intraepithelial neoplasia (VIN) represents an increasingly common, yet challenging diagnosis that shares many common risk factors with cervical intraepithelial neoplasia. However, unlike cervical intraepithelial neoplasia, effective screening and treatment strategies are much less defined for patients with VIN.

Objective

The objective of this article is to review the underlying risk factors leading to the development of VIN, identify special populations at risk for VIN, and outline acceptable treatment strategies.

Evidence Acquisition

This literature review was performed primarily using PubMed.

Results

Vulvar intraepithelial neoplasia can be separated into usual VIN (uVIN) and differentiated VIN (dVIN). The more common uVIN is related to underlying human papillomavirus infection, whereas dVIN occurs in the setting of other vulvar inflammatory conditions such as lichen sclerosis. Differentiated VIN carries a higher risk of progression to invasive malignancy. Extramammary Paget disease is a rare intraepithelial adenocarcinoma unrelated to uVIN and dVIN, although management is similar.

Conclusions and Relevance

Vulvar intraepithelial neoplasia is a preinvasive neoplasia of the vulva with few robust strategies for surveillance or management. Careful examination with targeted biopsy is warranted for suspicious lesions, and a combination of surgical and medical management can be tailored for individual patient needs.

Molecular Landscape of Vulvar Squamous Cell Carcinoma

Vulvar squamous cell carcinoma (VSCC) is a rare malignancy with dual pathogenesis, Human papillomavirus (HPV)-associated and HPV-independent, with a poorly explored molecular landscape. We aimed to summarize the findings of the series analyzing molecular hallmarks of this neoplasm. In January 2021, we conducted a comprehensive literature search using Pubmed Medline and Scopus to identify publications focused on genomic profiling of VSCC. Observational studies, including both prospective and retrospective designs, evaluating molecular alterations in VSCC were deemed eligible. A total of 14 studies analyzing 749 VSCC were identified. The study series were heterogeneous in HPV testing and sequencing strategies, included small sets of tumors and cancer genes, and commonly lacked survival analysis. Only one extensive targeted next-generation sequencing-based study comprised a large cohort of 280 VSCC. The mutated genes, their number, and frequencies were highly variable between the series. Overall, TP53 and CDKN2A, followed by PIK3CA, HRAS, and PTEN, were the most frequently studied and mutated genes. Mutations involved in the PI3K/AKT/mTOR pathway, including TP53, HRAS, KRAS, and PIK3CA, have been consistently reported across the studies. However, the role of individual mutations or pathways in the development of VSCC remains unclear. In conclusion, heterogeneity and the small sample size of available molecular series contribute to a limited view of the molecular landscape of VSCC. Large-scale genome- or exome-wide studies with robust HPV testing are necessary to improve the molecular characterization of VSCC.

[Vulvar intraepithelial neoplasias]

Vulvar squamous cell carcinoma arises from precursor lesions: vulvar intraepithelial neoplasias (VIN). Most of them are caused by the human papillomavirus (HPV), and the precursor lesion for this group is VIN usual type/high grade squamous intraepithelial lesion (uVIN/HSIL) of variable clinical presentation and having a light invasive potential. Some VIN are HPV-independent and arise in older women against the background of chronic dermatoses, mostly lichen sclerosus. Their histological diagnosis is more subtle. They have a higher invasive potential. A third precursor, leading to well-differentiated, or even verrucous, carcinomas, is still ill-defined to this day. We detail these lesions' clinics, histology, and biomarkers (immunohistochemical and molecular).

Diagnostic Criteria for Differentiated Vulvar Intraepithelial Neoplasia and Vulvar Aberrant Maturation

OBJECTIVE

The aim of the study was to describe the features required for diagnosis of differentiated vulvar intraepithelial neoplasia (dVIN) and vulvar aberrant maturation (VAM).

MATERIALS AND METHODS

The International Society of the Study of Vulvovaginal Diseases tasked the difficult pathologic diagnoses committee to develop consensus recommendations for clinicopathologic diagnosis of vulvar lichen planus, lichen sclerosus, and dVIN. The dVIN subgroup reviewed the literature and formulated diagnostic criteria that were reviewed by the committee and then approved by the International Society of the Study of Vulvovaginal Diseases membership.

RESULTS

Differentiated vulvar intraepithelial neoplasia is the immediate precursor of human papillomavirus (HPV)-independent vulvar squamous cell carcinoma and shows a spectrum of clinical and microscopic appearances, some overlapping with HPV-related neoplasia. The histopathologic definition of dVIN is basal atypia combined with negative or nonblock-positive p16 and basal overexpressed, aberrant negative, or wild-type p53. The most common pattern of dVIN is keratinizing with acanthosis, aberrant rete ridge pattern, and premature maturation. The morphologic spectrum of keratinizing dVIN includes hypertrophic, atrophic, acantholytic, and subtle forms. A few dVIN cases are nonkeratinizing, with basaloid cells replacing more than 60% of epithelium. Vulvar aberrant maturation is an umbrella term for lesions with aberrant maturation that arise out of lichenoid dermatitis and lack the basal atypia required for dVIN.

CONCLUSIONS

Evaluation of women at risk for dVIN and VAM requires a collaborative approach by clinicians and pathologists experienced in vulvar disorders. Close surveillance of women with lichen sclerosus and use of these recommendations may assist in prevention of HPV-independent squamous cell carcinoma through detection and treatment of dVIN and VAM.

HPV-independent Precursors Mimicking High-grade Squamous Intraepithelial Lesions (HSIL) of the Vulva

Two etiopathogenic types of vulvar squamous cell carcinoma (VSCC) have been described: human papillomavirus (HPV)-associated and HPV-independent. Precursor lesions, frequently identified in the adjacent skin, are also distinct in the 2 types of VSCC: high-grade squamous intraepithelial lesions (HSILs) in HPV-associated VSCC and differentiated vulvar intraepithelial neoplasia (dVIN) or vulvar acanthosis with altered differentiation in HPV-independent VSCC. Although HPV-independent precursors mimicking HSIL have been described in the vulva, their frequency and morphologic spectrum have not been completely characterized. We explored, in a large series of HPV-independent VSSC, the frequency and the histologic features of precursors mimicking HSIL. We included 779 DNA HPV-negative/p16-negative VSCC with at least 1 cm of adjacent skin. We evaluated the histologic and immunohistochemical (p16 and p53) characteristics of the intraepithelial lesions, focusing on precursors mimicking HPV-associated vulvar HSIL. A total of 254 tumors (33%) had adjacent premalignant lesions. Of them, 186 (73%) had dVIN, 22 (9%) had vulvar acanthosis with altered differentiation, and 46 (18%) had lesions that mimicked HSIL. The mean age of the patients with these HSIL-like lesions was 72±15 years. Twenty-six of these HSIL-like lesions had basaloid morphology, 13 warty, and 7 mixed basaloid/warty features. All the HSIL-like precursors were DNA HPV-negative/p16-negative; 74% of them showed p53 abnormal staining and 35% of them had areas of conventional dVIN. In conclusion, about one fifth of the HPV-independent precursors mimic HSIL, showing either basaloid or warty features. Older age and the presence of areas of typical HPV-independent intraepithelial lesions, together with p16 negativity, should raise suspicion of an HPV-independent etiology.

[Update on precursors of vulvar carcinoma]

Vulvar carcinomas represent 4% of all gynaecological cancers with 838 new cases in France in 2018. The precursor lesions of vulvar carcinomas are differentiated vulvar intraepithelial lesion (dVIN) in a context of lichen sclerosus and vulvar high-grade squamous intraepithelial lesion (HSIL) link to human papillomavirus (HPV) infection. Three typical clinical forms of HSIL are described: the Bowenoid papulosis, the Bowen's disease and the confluent VIN. Histopathology cannot differentiate effectively these two types of lesions. P16 and P53 immunostaining are valuable tools to respectively assess HPV infection and divide different types of dVIN. However, P53 immunostaining is still lacking sensibility to detect dVIN. First line therapies are medical treatment excluding the cases with a doubt of invasion. The gold standard treatment for dVIN and vulvar HSIL are respectively topical corticosteroids and imiquimod. Primary prevention for vulvar HSIL and dVIN are respectively HPV vaccination and early treatment of lichen sclerosus. Destructive therapy can be used in case of medical treatment failure such as CO2 laser, cryotherapy, dynamic phototherapy. Surgical indications should be carefully assessed between the risk of recurrence, the spread of the lesions, the aesthetic and functional aspect. Surgical procedures consist in either superficial vulvectomy or radical vulvectomy with or without flap reconstruction. Recurrence rate after surgery is around 20%.

p53 Immunohistochemical Patterns in HPV-Independent Squamous Cell Carcinomas of the Vulva and the Associated Skin Lesions: A Study of 779 Cases

Human papillomavirus (HPV)-independent vulvar squamous cell carcinomas (VSCC) and its precursors frequently harbour TP53 mutations. Recently, six p53 immunohistochemical (IHC) patterns have been defined, which have shown strong correlation with TP53 mutation status. However, few studies have applied this new six-pattern framework and none of them exhaustively compared p53 IHC positivity and patterns between invasive VSCC and adjacent skin lesion. We performed p53 IHC in a series of 779 HPV-independent VSCC with adjacent skin and evaluated the IHC slides following the newly described classification. Some 74.1% invasive VSCC showed abnormal p53 IHC staining. A skin lesion was identified in 450 cases (57.8%), including 254 intraepithelial precursors and 196 inflammatory/reactive lesions. Two hundred and ten of 450 (47%) VSCC with associated skin lesions showed an abnormal p53 IHC stain, with an identical staining pattern between the VSCC and the adjacent skin lesion in 80% of the cases. A total of 144/450 (32%) VSCC showed wild-type p53 IHC both in the invasive VSCC and adjacent skin lesion. Finally, 96/450 (21%) VSCC showed p53 IHC abnormal staining in the invasive VSCC but a wild-type p53 staining in the skin lesion. Most of the discordant cases (70/96; 73%) showed adjacent inflammatory lesions. In conclusion, the p53 IHC staining and pattern are usually identical in the VSCC and the intraepithelial precursor.

Comparison of p53 immunohistochemical staining in differentiated vulvar intraepithelial neoplasia (dVIN) with that in inflammatory dermatoses and benign squamous lesions in the vulva

AIMS

Differentiated vulvar intraepithelial neoplasia (dVIN), the precursor lesion to human papillomavirus-independent vulvar squamous cell carcinoma (VSCC), can be difficult to distinguish from vulvar inflammatory dermatoses. Our goal was to determine if p53 could be a useful biomarker for dVIN, by characterizing p53 percentage, intensity and patterns of staining in dVIN and its histological mimics.

METHODS AND RESULTS

We studied p53 immunohistochemical staining patterns in 16 dVIN cases and 46 vulvar non-neoplastic squamous lesions [12 lichen sclerosus (LS); seven lichen simplex chronicus; three lichen planus (LP); six psoriasis; 13 spongiotic dermatitis (SPO); and five candidiasis]. dVIN cases were adjacent to a p16-negative invasive VSCC in resection specimens. All dVIN cases showed null-type or moderate to strong uniform p53 staining in >70% of basal cells, with moderate to strong continuous parabasal staining extending to two-thirds of the epidermis. This was in contrast to weak or weak to moderate patchy p53 staining in the majority of other lesions. Moderate to strong and increased basal p53 staining (≥70%) was also observed in a subset of LS cases (5/12, 42%), LP cases (1/3, 33%), and SPO cases (36%, 4/11); however, in all categories, this was limited to the basal layer, and any staining in the parabasal layers was patchy.

CONCLUSION

Strong and uniform p53 staining of basal cells, extending into the parabasal layers, and a complete absence of staining (null type) is useful in distinguishing dVIN from other mimics in the vulva. p53 staining of lesser intensity or quantity, particularly basal overexpression only, overlaps with that in vulvar inflammatory lesions.

Vulval squamous cell carcinoma and its precursors

Vulval squamous cell carcinoma (VSCC) can arise through two distinct pathways [human papillomavirus (HPV)-associated and HPV-independent], and these VSCC variants are recognised as different disease entities on the basis of different aetiologies, morphological features, molecular events during oncogenesis, precursor lesions, prognosis, and response to treatment. The precursor of HPV-associated VSCC, variously referred to as high-grade squamous intraepithelial lesion (HSIL) [vulvar intraepithelial neoplasia (VIN) 2/3] or usual-type VIN, is morphologically identical to the more common HSIL (cervical intraepithelial neoplasia 2/3) of the cervix. The precursor lesions of HPV-independent VSCC include differentiated VIN, differentiated exophytic vulvar intraepithelial lesion, and vulvar acanthosis with altered differentiation; these have been under-recognised by pathologists in the past, leading to delays in treatment. This review will discuss the recent advances in diagnostic surgical pathology of VSCC and its precursors, and how these diagnoses can impact on patient management.

Major p53 immunohistochemical patterns in in situ and invasive squamous cell carcinomas of the vulva and correlation with TP53 mutation status

The recent literature has shown that vulvar squamous cell carcinoma (VSCC) can be stratified into two prognostically relevant groups based on human papillomavirus (HPV) status. The prognostic value of p53 for further sub-stratification, particularly in the HPV-independent group, has not been agreed upon. This disagreement is likely due to tremendous variations in p53 immunohistochemical (IHC) interpretation. To address this problem, we sought to compare p53 IHC patterns with TP53 mutation status. We studied 61 VSCC (48 conventional VSCC, 2 VSCC with sarcomatoid features, and 11 verrucous carcinomas) and 42 in situ lesions (30 differentiated vulvar intraepithelial neoplasia [dVIN], 9 differentiated exophytic vulvar intraepithelial lesions [deVIL], and 3 high-grade squamous intraepithelial lesions or usual vulvar intraepithelial neoplasia [HSIL/uVIN]). IHC for p16 and p53, and sequencing of TP53 exons 4-9 were performed. HPV in situ hybridization (ISH) was performed in selected cases. We identified six major p53 IHC patterns, two wild-type patterns: (1) scattered, (2) mid-epithelial expression (with basal sparing), and four mutant patterns: (3) basal overexpression, (4) parabasal/diffuse overexpression, (5) absent, and (6) cytoplasmic expression. These IHC patterns were consistent with TP53 mutation status in 58/61 (95%) VSCC and 39/42 (93%) in situ lesions. Cases that exhibited strong scattered staining and those with a weak basal overexpression pattern could be easily confused. The mid-epithelial pattern was exclusively observed in p16-positive lesions; the basal and parabasal layers that had absent p53 staining, appeared to correlate with the cells that were positive for HPV-ISH. This study describes a pattern-based p53 IHC interpretation framework, which can be utilized as a surrogate marker for TP53 mutational status in both VSCC and vulvar in situ lesions.

CD274 (PD-L1), CDKN2A (p16), TP53, and EGFR immunohistochemical profile in primary, recurrent and metastatic vulvar cancer

Vulvar squamous cell carcinoma can be divided by human papillomaviruses (HPV) status into two distinct clinicopathological and molecular entities. New agents targeting the tumor surface expression of programmed cell death-1/programmed cell death-ligand-1 are becoming a therapeutic option in an increasing number of carcinomas. We evaluate CD274 (PD-L1), CDKN2A (p16), tumor protein p53 (TP53), and epidermal growth factor receptor (EGFR) immunoexpression in primary tumors, recurrences and lymph node metastases and its correlations with prognosis and HPV status. We report 93 cases of vulvar squamous cell carcinoma diagnosed between 2002 and 2016 with the description of their clinicopathological features and prognosis data. Immunohistochemistry for CD274, CDKN2A, TP53, and EGFR was performed on tissue microarrays collecting from primary tumor, recurrences and lymph node metastasis. Kaplan-Meier estimator and multivariable Cox regression analysis controlling for FIGO stage and age were used. Patients who underwent surgery had a superior overall survival (HR = 0.51, 95% CI = 0.26-0.99 p = 0.04). Lymph node metastasis size ≥5 mm was associated with an inferior overall survival (HR = 1.88, 95% CI = 1.22-2.92 p = 0.004). CDKN2A expression was correlated with an inferior rate of recurrent disease (p = 0.02). In high-risk HPV DNA+ vulvar squamous cell carcinomas patients with CDKN2A- carcinomas showed a significantly worse overall survival than women with CDKN2A+ tumors (56% vs.100%, p = 0.003). TP53 expression was associated with an increased rate of recurrent disease (p = 0.0005). CD274 expression was associated with lymph node metastasis (p = 0.04). In 16 patients the CD274, CDKN2A, TP53, and EGFR expression changed between primary tumors, recurrences and lymph node metastases during tumor progression. In conclusion, a significant percentage of vulvar squamous cell carcinoma has a heterogeneous biomarker expression during tumor progression. We highlight the importance of some of these markers to be used as prognostic biomarkers. This data brings new light to future treatment using targeted therapy to EGFR or CD274 to include retesting such biomarkers in recurrence and lymph nodes metastases.

Role of human papillomavirus infection in the etiology of vulvar cancer in Italian women

Background

Vulvar squamous cell carcinoma (VSCC) is a rare malignancy of the female genital tract. We aimed to determine the mucosal high-risk human papillomavirus (HPV)-attributable fraction of VSCCs from Italian women using multiple markers of viral infections.

Methods

VSCCs and 8 metastatic lymph node samples from 107 Italian women were analyzed by a highly type-specific multiplex genotyping assay for the presence of DNA from 119 different HPVs. Tissues were further analyzed for HPV RNA and for upregulation of the cellular protein p16^INK4a.

Results

The rate of mucosal HPV-related tumors defined by viral DNA and RNA positivity was low (7.8%). HPV16 was the most prevalent, followed by 53, 56, and 58. Only five (4.9%) p16^INK4a-positive tumors were also positive for both viral DNA and RNA. One (14.3%) metastatic lymph node sample was positive for all three markers. DNA of cutaneous HPVs was detected in only two VSCCs, i.e. genus beta types 5 and 110.

Conclusion

A small proportion of Italian VSCCs is putatively HPV-related, i.e. positive for both viral DNA and RNA of the same type, thus reinforcing the importance of HPV vaccination. Moreover, this study suggests that a direct role of HPV from genus beta and gamma in vulvar carcinogenesis is unlikely.

Precursor lesions of vulvar squamous cell carcinoma - histology and biomarkers: A systematic review

The precursor lesion of vulvar squamous cell carcinoma (VSCC), namely vulvar intraepithelial neoplasia (VIN), is classified as: human papillomavirus (HPV)-related high grade squamous intraepithelial lesion (HSIL), and HPV-independent differentiated VIN (dVIN). Traditionally, histology and immunohistochemistry (IHC) have been the basis of diagnosis and classification of VIN. HSIL shows conspicuous histological atypia, and positivity on p16-IHC, whereas dVIN shows less obvious histological atypia, and overexpression or null-pattern on p53-IHC. For both types of VIN, other diagnostic immunohistochemical markers have also been evaluated. Molecular characterization of VIN has been attempted in few recent studies, and novel genotypic subtypes of HPV-independent VSCC and VIN have been identified. This systematic review appraises the VSCC precursors identified so far, focusing on histology and biomarkers (immunohistochemical and molecular). To gain further insights into the carcinogenesis and to identify additional potential biomarkers, gene expression omnibus (GEO) datasets on VSCC were analyzed; the results are presented.

Prognostic Significance of P16 Expression and P53 Expression in Primary Vaginal Cancer

To evaluate the correlation between p16 expression and clinical outcomes in patients with primary vaginal cancer treated with definitive radiotherapy. P16 immunohistochemical was performed on 25 patient samples and recorded from pathology reports in 7 patients. P53 immunohistochemical was performed on 3 p16-negative samples. Baseline characteristics were compared using the Fisher exact test. Outcomes were compared using log-rank tests, and cox proportional hazards models. Survival and recurrence analysis was performed with the Kaplan-Meier method and cumulative incidence estimates. P16 expression was positive in 29 patients and negative in 3 patients. Two of the p16-negative tumors showed positive expression of p53. The median overall survival, progression-free survival and 2-yr cumulative incidence of recurrence were 66 mo [95% confidence interval (CI), 31-96], 34 mo (95% CI, 21-86), and 19% (95% CI, 7%-34%), respectively. P16-positive tumors had higher median overall survival and progression-free survival compared with p16-negative tumors (82 vs. 31 mo, P=0.02 and 35 vs 16 mo, P=0.04, respectively). The 2-yr cumulative incidence of recurrence was 14% for p16-positive tumors compared with 67% for p16-negative tumors (P=0.07). On univariable analysis, p16-negative status, age older than 65, and advanced stage were associated with inferior overall survival. P16 negativity is an independent predictor of inferior overall survival. P16-positive vaginal cancers have a better prognosis and decreased incidence of recurrence compared with p16-negative tumors. These prognostic findings associated with p16-negative vaginal cancers will need to be confirmed in larger patient cohorts.

Human Papillomavirus-Independent Squamous Lesions of the Vulva

The pathogenesis of vulvar squamous neoplasia has 2 pathways: human papillomavirus (HPV)-dependent and HPV-independent. The HPV-dependent pathway in the vulva follows the same progression as HPV-dependent lesions elsewhere in the gynecologic tract-HPV infection results in high-grade squamous intraepithelial lesion with subsequent progression to basaloid squamous cell carcinoma. The HPV-independent pathway is more complex, with a variety of precursor lesions and molecular alterations. Although the most recognized form of HPV-independent vulvar lesion is differentiated vulvar intraepithelial neoplasia, recent explorations have elucidated new precursors. This review provides an update on HPV-independent risk factors and precursor lesions for squamous cell carcinoma of the vulva.

Human papillomavirus in laryngeal and hypopharyngeal lymphoepithelial carcinoma

The involvement of human papillomavirus (HPV) in laryngeal and hypopharyngeal lymphoepithelial carcinoma was investigated in a series of ten cases (seven laryngeal and three hypopharyngeal), retrieved from the files of three tertiary hospitals in the 2000-2017 period, through polymerase chain reaction with SPF10 primers and INNO-LiPA HPV Genotyping Extra II (Innogenetics). Epstein-Barr virus (EBV) was tested in all cases with in situ hybridization INFORM EBER Probe (Ventana Medical Systems). p16 and p53 expression were immunohistochemically analyzed. Calculated annual incidence was 0.013/100,000, and prevalence was 0.2% of laryngeal and hypopharyngeal carcinomas. All cases were EBV negative. HPV was detected in five cases, three of which also overexpressed p16. HPV16 was detected in four cases, and HPV58 in one case. Five cases were HPV negative, only one of these five overexpressed p16. No recurrence was observed in nine cases during follow-up. The 5-year disease-specific-survival rate was 100%. Mean overall survival was 87 months. Lymphoepithelial carcinoma of the larynx and hypopharynx are not related to EBV. Simultaneous HPV+/p16+ is consistent with HPV causation in a fraction of laryngeal and hypopharyngeal lymphoepithelial carcinomas.

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.

A Retrospective 20-Year Analysis of Proliferative Verrucous Leukoplakia and Its Progression to Malignancy and Association with High-risk Human Papillomavirus

Proliferative verrucous leukoplakia (PVL) is defined as an aggressive, relentless and recalcitrant form of leukoplakia that has a high propensity for malignant transformation. The aim of this study was to evaluate the malignant potential of PVL and determine its possible association with high-risk human papillomavirus (HPV). Twenty cases with a clinical and biopsy proven diagnosis of PVL were collected from the University of Florida Oral Medicine clinic database. Immunohistochemistry was performed to evaluate the expression of p16INK4A and p53 genes in the PVL lesions. The lesions were also tested for high-risk HPV by DNA in-situ hybridization. The average age of the patients at the time of first biopsy was 62.7 years. Most patients had multiple sites of involvement, gingiva being the most common location. The lesions progressed to malignancy in approximately 50% of patients. The expression of p16INK4A gene was considered negative, with at least a 50-65% immunoreactivity observed in only three cases that progressed to malignancy. No expression of high-risk HPV was detected, whereas p53 staining was positive in less than 25% of the cells demonstrating gene expression. No definite association between PVL and high-risk HPV infection could be established. Due to the high transformation potential of PVL, early recognition with aggressive treatment, including multiple biopsies, and continued close clinical follow-up, remain the mainstay of favorable management of this condition.

Differentiated vulvar intraepithelial neoplasia (dVIN): the most helpful histological features and the utility of cytokeratins 13 and 17

Differentiated vulvar intraepithelial neoplasia (dVIN) is the precursor lesion of HPV-negative vulvar squamous cell carcinoma (VSCC). The histopathological diagnosis of dVIN can be challenging, as it often resembles vulvar non-neoplastic epithelial disorders (NNED), especially lichen sclerosus (LS). We aimed to establish the most specific and reproducible histological features of dVIN and assessed cytokeratin 13 (CK13) and cytokeratin 17 (CK17) immunohistochemistry as a diagnostic aid. Consecutive cases of dVIN (n = 180) and LS (n = 105) from the period 2010 to 2013 were reviewed using a checklist of histological features. Each feature was recorded as ‘present’ or ‘absent’ and statistical comparison (dVIN vs LS) was made. Interobserver agreement between two pairs of pathologists was assessed for a subset of cases of dVIN (n = 31) and LS and other NNED (n = 23). Immunohistochemistry with CK13, CK17, MIB1 and p53 was performed on dVIN, LS, and other NNED cases. Macronucleoli, features of disturbed maturation and angulated nuclei were significantly more common in dVIN than LS (p < 0.001). We found ‘substantial agreement’ for the diagnosis of dVIN (κ = 0.71). Macronucleoli and deep keratinisation had the highest agreement. In dVIN, the mean percentage of cells staining with CK13 was 15 and with CK17, this was 74. For LS, the mean percentage of cells staining with CK13 was 31, and with CK17, this was 41. By plotting receiver operating characteristic curves (ROC), an area under the curve (AUC) of 0.52 was obtained for CK13, and an AUC of 0.87 was obtained for CK17. The most helpful histological features for diagnosing dVIN were macronucleoli, features of disturbed maturation, and angulated nuclei. Increased CK17 expression may have promise for supporting dVIN diagnosis.

Polymorphous Sweat Gland Carcinoma: An Immunohistochemical and Molecular Study

Polymorphous sweat gland carcinoma is an uncommon low-grade malignant adnexal tumor with a marked predilection for the distal extremities. Histologically, the lesions are characterized by a cellular proliferation showing a combination of growth patterns, including trabecular, solid, tubular, cribriform, or adenoid cystic and pseudopapillary. The immunohistochemical and molecular profile of these tumors has not yet been properly addressed. We have studied 3 cases of polymorphous sweat gland carcinoma using a broad panel of immunohistochemical markers including cytokeratin AE1/AE3, CK5/6, MOC31, p40, p63, p16, chromogranin, synaptophysin, CD56, MIB-1, estrogen receptor, progesterone receptor, androgen receptor, BER-EP4, smooth muscle actin, epithelial membrane antigen, carcinoembryonic antigen, CD117, S100 protein, HBME-1, DOG1, vimentin, and mammaglobin. We also examined for the MYB-NFIB fusion by fluorescent in situ hybridization (ISH) and for human papilloma virus by ISH. Our studies show that cytokeratin AE1/AE3, CK5/6, p40, p63, p16, chromogranin, and CD56 stains were positive in all 3 cases. All 3 cases were negative for MYB-NFIB fusion by fluorescent ISH which rules out adenoid cystic carcinoma. DNA ISH studies for high-risk human papilloma virus were negative in all cases. MIB-1 proliferation index was very high (30%-70% nuclear positivity), supporting a malignant phenotype. The positivity for chromogranin and CD56 suggests partial neuroendocrine differentiation. The differential diagnosis includes metastases from internal malignancies, basal cell carcinoma, and other benign and malignant adnexal neoplasms such as adenoid cystic carcinoma, ductal eccrine carcinoma, and microcystic carcinoma. Positivity for p16 in combination with chromogranin and CD56 may be potentially good markers for differentiating this tumor from other adnexal tumors.

P16 Expression in Extramammary Paget's Disease of the Vulva and Scrotum Is Not Human Papillomavirus Related

INTRODUCTION

Extramammary Paget disease (EMPD) of the vulva has been shown to express p16 by immunohistochemistry (IHC), however, p16 expression in the vulva and scrotum has not been extensively studied in relation to human papillomavirus (HPV) within EMPD of both the vulva and scrotum.

DESIGN

Twenty-two cases of EMPD (vulva, 16; scrotum, 6) were found in our laboratory information system. P16 and HPV IHC were performed. Any p16 reactivity less than 10% was considered negative. HPV in situ hybridization for both low- and high-risk HPV was also performed on all cases.

RESULTS

Of the 6 scrotal EMPD, 3 (50%) showed weak to moderate positive reactivity for p16 by IHC. Of the 16 vulvar EMPD, 13 (81%) were positive for p16, with at least moderate (2+) intensity with a mean expression of 33.3% (range = 10% to 80%) and 62% (range = 20% to 95%) in scrotal and vulvar EMPD, respectively. None of the scrotal or vulvar cases showed positive reactivity for HPV either by IHC or in situ hybridization.

CONCLUSION

Both vulvar and scrotal EMPD can express p16 by IHC, more commonly vulvar than scrotal; however, no HPV was detected either by IHC or in situ hybridization. EMPD of vulva and scrotum does not appear to be related to HPV, and p16 expression may be regulated through a different mechanism.

p16 Expression and Biological Behavior of Flat Vulvar Low-grade Squamous Intraepithelial Lesions (LSIL)

Flat low-grade squamous intraepithelial lesion (LSIL) of the vulva [vulvar intraepithelial neoplasia (VIN) 1, flat condyloma] is an uncommon entity with poorly understood biological behavior. We aimed to determine the risk of subsequent vulvar high-grade squamous intraepithelial lesion (HSIL) or carcinoma following a diagnosis of vulvar LSIL/VIN 1, as well as the frequency and predictive value of p16 immunohistochemical expression in this setting. Of the 51 included cases, p16 positivity (diffuse block staining) was identified in 2 (4%). Follow-up data were available in 34 cases, of which 2 (5.9%) developed subsequent vulvar HSIL, including 1/2 p16-positive cases and 1/32 p16-negative cases. The difference in HSIL frequency between p16-positive and p16-negative cases was not statistically significant (P=0.116 for VIN 2+, P=0.061 for VIN 3). For the 18 patients with treatment information available, 10 (56%) received medical or surgical treatment after biopsy. Our results indicate that flat vulvar LSIL is infrequently p16 positive, and that few patients with vulvar LSIL develop subsequent vulvar HSIL. Despite the use of destructive treatment in some cases, the data provide support for the nonpreneoplastic nature of the entity. Immunohistochemical expression of p16 may not be a predictor of HSIL risk in vulvar LSIL, although this result may also be related to the very low rates of both p16 positivity and subsequent vulvar HSIL in our sample. It is clear that vulvar LSIL is distinct from LSIL in other lower anogenital sites in terms of its behavior and p16 expression frequency.

The Role of Photodynamic Therapy in the Treatment of Vulvar Intraepithelial Neoplasia

Background: vulvar intraepithelial neoplasia is a non-invasive precursor lesion found in 50–70% of patients affected by vulvar squamous cell carcinoma. In the past, radical surgery was the standard treatment for vulvar intraepithelial neoplasia, however, considering the psychological and physical morbidities related to extensive surgery, several less aggressive treatment modalities have been proposed since the late 1970s. Photodynamic therapy is an effective and safe treatment for cutaneous non-melanoma skin cancer, with favorable cosmetic outcomes. Methods: in the present paper, the results of selected studies on photodynamic therapy in the treatment of vulvar intraepithelial neoplasia are reported and discussed. Results: Overall, complete histological response rates ranged between 20% and 67% and symptom response rates ranged between 52% and 89% according to different studies and case series. Conclusions: the real benefit of photodynamic therapy in the setting of vulvar intraepithelial neoplasia lies in its ability to treat multi-focal disease with minimal tissue destruction, preservation of vulvar anatomy and excellent cosmetic outcomes. These properties explain why photodynamic therapy is an attractive option for vulvar intraepithelial neoplasia 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.

Does Differentiated Squamous Intraepithelial Neoplasia Occur in the Cervix?

BACKGROUND

Invasive cervical cell squamous carcinoma (ICC) classically develops from high grade cervical intraepithelial neoplasia of usual type (uCIN). Differentiated cervical intraepithelial neoplasia (dCIN) analogue to differentiated vulvar intraepithelial neoplasia has not been described in the cervix.

METHODS

A pilot case of ICC developing from dCIN with atypia limited to the basal/parabasal layers, focally associated with neoplastic spread above the parabasal layer (usual-like CIN pattern or u-like CIN) was identified. The previous cervical biopsy was under-diagnosed as low grade CIN. A total of 33 consecutive cases of ICC were reviewed to identify dCIN, u-like CIN and uCIN.

RESULTS

The ICC developed from dCIN/u-like CIN in 2 patients, 46 and 47-year-old (group 1), mixed dCIN/u-like CIN and uCIN in 7 patients, 36±3-year-old (group 2) and from uCIN in 24 patients, 47±9-year-old (group 3). In group 1, focal uCIN but not connected to ICC was also seen and Pap smears showed only hyper-keratinized cells with mildly atypical nuclei. Endocervical gland involvement by CIN was absent in group 1, focal in group 2 and extensive in group 3. All cases showed diffuse p16 staining. P53 reactivity was noted in basal/parabasal in dCIN, predominantly lower and upper parts of the epithelium in groups 2 and 3, respectively.

CONCLUSIONS

Totally, 27% of ICC cases had associated dCIN/u-like CIN and in younger patients than in the uCIN group. Larger studies are needed to confirm dCIN/u-like CIN as significant precursor lesions of ICC.

Role of Human Papillomavirus in Vulvar Cancer

Human papillomavirus (HPV) is involved in one of the at least 2 pathways leading to vulvar squamous cell carcinoma (VSCC). Inactivation of p53 and retinoblastoma by the viral products E6 and E7 is involved in malignant transformation. The percentage of HPV-positive VSCCs ranges from 18% to 75%, depending on the geographical area. HPV-associated tumors affect relatively young women and arise from high-grade intraepithelial lesions, identical to other HPV-associated premalignant lesions of the anogenital tract. HPV-independent tumors tend to affect older women and usually arise in a background of inflammatory skin disorders and a subtle variant of in situ lesion called differentiated vulvar intraepithelial neoplasia. HPV-positive tumors tend to be of basaloid or warty types, whereas HPV-independent tumors tend to be of keratinizing type, but there is frequent overlap between histologic types. There is no conclusive evidence yet on the best strategy in terms of determining HPV attribution. HPV DNA detection is generally considered the gold standard although there is some concern about misclassification when using this technique alone. p16 immunostaining has shown to be an excellent surrogate marker of HPV infection. Positive results for both techniques are considered the best evidence for HPV-association. The prognostic role of HPV in VSCC is still contradictory, but increasing evidence suggests that HPV-associated tumors are less aggressive. Currently, there are no differences in treatment between HPV-associated and HPV-independent VSCC, but novel immunological strategies based on anti-HPV antigens are being evaluated in clinical trials.

The changing landscape of gynaecological cancer diagnosis: implications for histopathological practice in the 21st century

The era of molecular medicine has led to dramatically improved understanding of the genetic events that give rise to different types of cancers. In the case of gynaecological malignancies, this has resulted in distinct shifts in how these tumours are diagnosed in routine surgical pathology practice, with an increased emphasis on accurate subtype diagnosis. This has happened across all sites in the gynaecological tract and for most cell types, but in ways that are site-specific and may appear to be subtle, as in most instances the diagnostic terminology has not changed. For example, the diagnosis of clear cell carcinoma of the ovary is still in use, but the diagnostic criteria and clinical implications are different in 2017 from what they were in 2000. As a result, there can be a failure to appreciate how important these changes are and the resulting necessity of incorporating them into our daily practice. In this review we will describe changes in diagnostic surgical pathology occasioned by improved understanding of molecular events during pathogenesis, for cancers of ovary/tube, endometrium, cervix and vulva, and highlight how current practice differs from that of only a few years ago.

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.

A rare case of HPV-negative cervical squamous cell carcinoma

It is generally assumed that virtually all cervical squamous cell carcinomas are associated with persistent infection by high-risk human papillomavirus (HPV), although it is well known that unusual variants of cervical adenocarcinoma are mostly HPV negative. We report a case of a well-differentiated cervical squamous cell carcinoma in a 54-yr-old woman, the morphologic features of which suggested a non-HPV-related neoplasm. The tumor was p16 negative. HPV was also negative by 2 methods, including the highly sensitive SPF-10 system. Further study of additional cases is needed to establish the etiological and pathogenetic factors that underlie very rare non-HPV-related cervical squamous cell carcinoma.

VIN usual type-from the past to the future

Usual vulvar intraepithelial neoplasia (uVIN) is the most common VIN type, generally related to a human papillomavirus (HPV) infection, predominantly type 16. The incidence of uVIN has been increasing over the last decades, and a bimodal peak is observed at the age of 40–44 and over 55 years.

Almost 40% of patients with uVIN have a past, concomitant or future HPV-associated lesion of the lower genital tract. HPV-related malignancies are associated with a persistent HPV infection. The host immune response is of crucial importance in determining clearance or persistence of both HPV infections and HPV-related VIN. About 60% of the patients present with symptoms. Clinical features of uVIN vary in site, number, size, shape, colour, and thickness of lesions. Multicentric disease is often present.

Most uVIN lesions are positive at immunohistochemistry to p16^ink4a and p14^arf, but negative to p53.

Irrespective of surgical treatment used, uVIN recurrence rates are high. Positive margins do not predict the development of invasive disease and the need to re-excide the tissue around the scare remains to be demonstrated. Therefore, considering the low progression rate of uVIN and psycosexual sequelae, treatments should be as conservative as possible.

Medical treatments available are mainly based on immunotherapy to induce normalisation of immune cell count in uVIN. None are approved by the food and drug administration (FDA) for the treatment of uVIN. If medical treatment is performed, adequate biopsies are required to reduce the risk of unrecognised invasive disease. Some studies suggest that failure to respond to immunotherapy might be related to a local immunosuppressive microenvironment, but knowledge of the uVIN microenvironment is limited. Moreover, our knowledge of the potential mechanisms involved in the escape of HPV-induced lesions from the immune system has many gaps.

HPV vaccines have been demonstrated to be effective in preventing uVIN, with 94.9% efficacy in the HPV-naive population, while studies on therapeutic vaccines are limited. The low incidence of VIN requires large multicentre studies to determine the best way to manage affected patients and to investigate the immunological characteristics of the ‘vulvar microenviroment’ which leads to the persistence of HPV.

A clinical and pathological overview of vulvar condyloma acuminatum, intraepithelial neoplasia, and squamous cell carcinoma

Condyloma acuminatum, intraepithelial neoplasia, and squamous cell carcinoma are three relatively frequent vulvar lesions. Condyloma acuminatum is induced by low risk genotypes of human papillomavirus (HPV). Vulvar intraepithelial neoplasia (VIN) and squamous cell carcinoma have different etiopathogenic pathways and are related or not with high risk HPV types. The goal of this paper is to review the main pathological and clinical features of these lesions. A special attention has been paid also to epidemiological data, pathological classification, and clinical implications of these diseases.

Phosphorylated S6 as an immunohistochemical biomarker of vulvar intraepithelial neoplasia

As life expectancy lengthens, cases of non-viral-associated vulvar squamous cell carcinoma and its precursor lesion, so-called differentiated vulvar intraepithelial neoplasia (VIN), continue to increase in frequency. Differentiated VIN often is difficult to recognize and failure to detect it before invasion results in morbidity and mortality. Thus, identification of a reliable biomarker for this type of lesion would be of great clinical benefit. Our recent studies have identified activation (ser235/236 phosphorylation) of ribosomal protein S6 (p-S6) in basal epithelial cells as an event that precedes and accompanies laminin γ(2) overexpression in most preinvasive oral dysplasias. To test this as a potential biomarker of vulvar dysplasia, we immunostained seven differentiated VINs and nine papillomavirus-related 'classic' VINs, most of which were associated with carcinoma, for p-S6. All carcinomas, all differentiated VINs, and most classic VINs contained regions of p-S6 staining in the basal layer, whereas basal and parabasal cells of normal vulvar epithelium and hyperplastic and inflamed lesions lacking cellular atypia were p-S6 negative. Laminin γ(2) was expressed in a subset of VINs, always occurring within basal p-S6 positive regions, as we had found previously for oral dysplasias. Lichen sclerosus is considered a potential precursor of vulvar carcinoma. Two lichen sclerosus lesions of patients with a concurrent carcinoma and one of six lichen sclerosus lesions without atypia or known concurrent carcinoma were basal p-S6 positive. In summary, there is a distinct difference in p-S6 basal cell layer staining between benign and neoplastic vulvar squamous epithelium, with consistent staining of differentiated VIN and of some lichen sclerosus lesions. These results support further studies to assess the potential of p-S6 as a biomarker to identify vulvar lesions at risk of progressing to invasive cancer.

Investigation of prognostic significance of CD109 expression in women with vulvar squamous cell carcinoma

OBJECTIVE

The goal of this study was to investigate the between cluster of differentiation 109 (CD109) expression and tumor diameter, invasion depth, tumor grade, presence of lymph-node metastasis, and overall survival in patients with vulvar squamous cell carcinoma, which is the most common type of vulvar cancer.

METHOD

Twenty-six patients who underwent an operation for vulvar cancer between 1999 and 2009 in our clinic were included in this study. Immunohistochemical staining was performed on formalin-fixed and paraffin-embedded tissue.

RESULT

Tumor diameter was not found to be significantly associated with CD109 expression, intensity of cytoplasmic staining, or combined score (P = 0.325, P = 0.169, P = 0.352, respectively). Invasion depth and combined score were also not significantly correlated with CD109 expression (P = 0.324 and P = 0.174 respectively). There was a negative correlation between invasion depth and the intensity of cytoplasmic staining (P = 0.042). There was no significant correlation between tumor stage and CD109 expression, the intensity of cytoplasmic staining, and the combined score (P = 0.574, P = 0.389, P = 0.605, respectively). A significant positive correlation was observed between tumor grade and CD109 expression, the intensity of cytoplasmic staining, and the combined score (P = 0.003, P = 0.018, P = 0.008, respectively). No significant difference was found between the percentages of CD109 expression in patients with positive (48%) and negative (11%) lymph nodes (P = 0.058). The percentage of CD109 expression did not significantly differ in relation to overall survival (P = 0.483).

CONCLUSION

Comprehensive and more extensive studies are needed to examine the relationship between CD109 expression and vulvar malignant lesions.

Expression of p16 protein in lesional and perilesional condyloma acuminata and bowenoid papulosis: clinical significance and diagnostic implications

BACKGROUND

The histopathological and clinical overlapping features between condyloma acuminata and bowenoid papulosis can present a diagnostic challenge and we sought to determine if immunochemistry can be helpful in this setting.

OBJECTIVE

In this study, we evaluate the specificity and sensitivity of p16 immunohistochemistry in condyloma and bowenoid papulosis lesions compared with uninvolved perilesional skin and discuss the possible clinical implications.

METHODS

A total of 36 skin biopsy specimens (24 samples of condyloma and 12 samples of bowenoid papulosis with adjacent uninvolved perilesional skin) were stained with an antibody to p16 protein.

RESULTS

In all, 75% of condyloma lesions showed sporadic and focal positive staining for p16 protein. All cases of bowenoid papulosis showed diffuse positive staining with p16 protein. Normal-appearing adjacent skin was negative in all cases.

LIMITATIONS

Studies with a larger number of cases are needed to confirm our data.

CONCLUSION

This immunostain has high sensitivity and specificity for the detection of bowenoid papulosis. Although p16 is expressed in both conditions, the staining pattern in bowenoid papulosis is strongly and diffusely positive involving the full thickness of the epidermis compared with the mostly focal or sporadic pattern observed in condyloma.

Coexisting high-grade vulvar intraepithelial neoplasia (VIN) and condyloma acuminatum: independent lesions due to different HPV types occurring in immunocompromised patients

The majority of vulvar intraepithelial neoplasia (VIN) is high-grade and is related to high-risk human papillomavirus (HRHPV) (most commonly HPV 16). It is considered to be the precursor of HRHPV-related vulvar squamous cell carcinoma. Vulvar condyloma acuminatum is low-risk HPV (LRHPV)-related (most commonly types 6 and 11) and has virtually no risk of neoplastic progression. While infection with multiple LRHPV and HRHPV types has been reported for cervical squamous intraepithelial lesions, coexisting vulvar condyloma and adjacent high-grade VIN have not been well characterized. Eleven cases of concurrent condyloma acuminatum and adjacent flat high-grade VIN and 3 cases of high-grade VIN with prominent condylomatous architecture were analyzed using immunohistochemical analysis of p16 expression, in situ hybridization (ISH) for HPV detection [HPV 6/11, HPV 16, HPV 18, and HPV wide spectrum (types 6, 11, 16, 18, 31, 33, 35, 45, 51, 52) probes], and HPV typing by a polymerase chain reaction (PCR)-based method (in select cases). All patients had underlying immunosuppressive conditions (human immunodeficiency virus infection or posttransplant therapy). Among the 11 cases of concurrent high-grade VIN and condyloma, the lesions were directly adjacent to one another in 5 cases (with 2 of these demonstrating an intimate admixture of lesions), and in 6 cases the lesions were found in separate tissue sections from the same specimen. Diffuse/strong p16 expression was seen in all high-grade VIN lesions, whereas patchy/weak staining was found in all condylomata. All condylomata contained HPV 6 or 11 as detected by ISH. HRHPV was detected in all of the accompanying high-grade VIN lesions. Ten contained HPV 16 (9 by ISH, 1 by PCR), with the remaining case containing multiple HPV types by PCR. All condylomatous high-grade VIN lesions demonstrated diffuse/strong p16 expression and had evidence of HRHPV (1 with HPV 16 by ISH, 1 with HPV 18 by ISH, and 1 with multiple HPV types by PCR), with no detection of HPV 6 or 11 by ISH. The restriction of LRHPV to condylomatous components and HRHPV to high-grade VIN components of adjacent lesions suggests these are independent lesions caused by different HPV types. Diffuse p16 expression can highlight small foci of high-grade VIN, which may be overlooked in more abundant condylomatous tissue from immunosuppressed patients. The presence of only HRHPV in those VIN lesions with high-grade cytologic features but prominent condylomatous architecture supports their classification as forms of pure high-grade VIN and distinguishes them from condyloma acuminatum.

In oral squamous cell carcinoma, high FAK expression is correlated with low P53 expression

Focal adhesion kinase (FAK) and p53 have been associated with metastatic activity and a poor prognosis in oral squamous cell carcinoma (OSCC). Recently, a feedback mechanism in which FAK regulates p53 has been proposed. The present study aims to determine the role of p53 in FAK regulation in these tumors. FAK and p53 expression was examined by immunohistochemistry in normal oral mucosa and in 67 oral squamous cell carcinomas. p16(INK4a) was also studied in view of its association with human papillomavirus infection. The association between FAK and p53 was subsequently analyzed. FAK expression in OSCCs was heterogeneous: 22 (33 %) cases showed weak expression, 16 (24 %) showed moderate expression, and 22 (33 %) cases showed high expression. Regarding p53, 31 of 67 (46 %) available tumor specimens showed negative staining, and 36 of 67 (54 %) showed positive nuclear staining for p53. FAK expression was inversely correlated with p53 expression (Fisher's exact test, p = 0.005). There was no association between p16(INK4a) and p53 or FAK expression. In conclusion, our results support the hypothesis that FAK activity might be involved in the down-regulation of p53 expression in OSCC.