Squamous Cell Carcinoma In Situ-The Importance of Early Diagnosis in Bowen Disease, Vulvar Intraepithelial Neoplasia, Penile Intraepithelial Neoplasia, and Erythroplasia of Queyrat

Cutaneous squamous cell carcinoma (cSCC) is the second-most-prevalent malignancy in humans. A delayed diagnosis of cSCC leads to heightened invasiveness and positive surgical margins. Bowen's disease (BD) represents an early form of cSCC and presents as a small erythematous, photo-distributed, psoriasiform plaque. Although certain dermoscopy features in BD are quite characteristic, histopathology remains the gold standard for diagnosis and provides a severity-scoring system that assists in guiding appropriate treatment strategies. The classification of precancerous lesions of the vulva and penis has undergone multifarious transformations due to variations in clinical and histopathological characteristics. Presently, erythroplasia of Queyrat is categorized as a clinical variant of penile intraepithelial neoplasia (PeIN). The diagnoses of vulvar intraepithelial neoplasia (VIN) and PeIN present significant challenges and typically necessitate one or more biopsies, potentially guided by dermoscopy. Aceto-white testing demonstrates a notably high negative predictive value for genital precancerous lesions. Histopathological examination represents the gold-standard diagnosis in VIN and PeIN, while p16 and p53 immunostainings alongside HPV testing provide crucial diagnostic clues. The histopathologic features, degree of differentiation, and associations with lichen planus, lichen sclerosus, and HPV guide the selection of conservative treatments or surgical excision.

A Mimicker of Differentiated Vulvar Intraepithelial Neoplasia: Reactive Atypia From Noncompliance With Lichen Sclerosus Therapy

ABSTRACT

Differentiated vulvar intraepithelial neoplasia (d-VIN) is an HPV-independent precursor to vulvar squamous cell carcinoma. The histology of d-VIN lesions is difficult to differentiate from that of non-neoplastic epithelial disorders, especially lichen sclerosus (LS). The authors present a case of LS, where relying on histopathology alone could have led to misdiagnosis. The patient was a 17-year-old female patient with clinical features of vulvar dermatitis and LS for 2 years. She was counseled to apply clobetasol 0.05% to the affected area daily but reported no improvement after 6 months. A biopsy of the right labia majora revealed histologic findings typical of d-VIN and near-contiguous p53 expression. These features are characteristic of d-VIN. However, d-VIN is exceedingly rare in young patients. The case was reviewed by 6 dermatopathologists and gynecologic pathologists, who observed that the degree of inflammation would be unusual postclobetasol therapy and could be due to noncompliance. A review of the patient's chart revealed that she "does not always remember to apply" clobetasol. The patient's clinician confirmed that there were compliance issues, and the follow-up biopsy was negative for d-VIN. The case was signed out as LS, with a note describing the above, and to rebiopsy if concern persisted. The authors conjecture that inflammatory infiltrates in the biopsied area caused reactive atypia due to lack of adherence to treatment. Although the patient's age helped rule out d-VIN, similar cases in elderly patients may be occurring. Pathologists must be aware that reactive forms of untreated LS can mimic d-VIN, to avoid misdiagnosis.

Morphological Characteristics of Various Cells in Esophageal Squamous Dysplasia: Extremely Wide Morphological Spectrum

The WHO classification of esophageal tumors divides esophageal squamous intraepithelial dysplasia into high and low grades, but does not specify its morphological spectrum. Here, the morphological characteristics of various cells were investigated in esophageal squamous (high-grade) dysplasia, and a morphological spectrum and terminology for this lesion were proposed to avoid misdiagnosis. The clinicopathological data of 540 patients with esophageal squamous dysplasia were analyzed retrospectively. According to the unique cytomorphological characteristics of the lesions and the predominant cell type, the esophageal squamous dysplasia was divided into the following morphological groups: classic type (34.6%, 187/540), basaloid subtype (10.7%, 58/540), spindle-cell subtype (4.6%, 25/540), differentiated subtype (48.9%, 264/540), and verrucous subtype (1.1%, 6/540). Gender, age, and lesions location did not differ among the subtypes (P > 0.05), while Paris classification and lesions diameter significantly differed among the subtypes (P < 0.01). Classic-type cells showed severe atypia. In the basaloid subtype, the cells were small, and resembled basal cells; most of these lesions were of the 0-IIb type with small lesion diameter. In the spindle-cell subtype, the cells and nuclei were spindle-shaped or long and spindle-shaped and arranged in parallel. Differentiated-subtype showed well-to-moderately differentiated cells, and epithelial basal cells were mature. Verrucous-subtype showed well-differentiated cells, and were characterized by verrucous or papillary structures. Esophageal squamous dysplasia has extremely wide morphological spectrum. Awareness of the spectrum of morphological presentations of this lesion, specifically the basaloid subtype, spindle-cell subtype, differentiated subtype, and verrucous subtype, is important for accurate diagnosis.

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.

Vulval premalignant lesions: a review article

Vulvar intraepithelial neoplasia (VIN) is a noninvasive squamous lesion that is a precursor of vulvar squamous cell cancer. Currently, no screening tests are available for detecting VIN, and a biopsy is performed to confirm the clinical diagnosis. Despite sharing many risk factors with cervical intraepithelial neoplasia, the diagnosis of VIN is poses challenges, contributing to its increasing prevalence. This study aimed to analyze the underlying risk factors that contribute to the development of VIN, identify specific populations at risk, and define appropriate treatment approaches. Differentiated VIN (dVIN) and usual VIN (uVIN) are the classifications of VIN. While dVIN is associated with other vulvar inflammatory disorders, such as lichen sclerosis, the more prevalent uVIN is associated with an underlying human papillomavirus infection. Patients with differentiated VIN have an increased risk of developing invasive malignancies. Few effective surveillance or management techniques exist for vulvar intraepithelial neoplasia, a preinvasive neoplasm of the vulva. For suspicious lesions, a thorough examination and focused biopsy are necessary. Depending on the specific needs of each patient, a combination of surgical and medical approaches can be used.

Identification of potential prognostic biomarkers in vulval squamous cell carcinoma based on human papillomavirus infection Status-Analysis of GSE183454

This study aimed to elucidate the differences in vulval squamous cell carcinomas (VSCC) based on the HPV infection status. The sequencing data GSE183454 which contains 23 VSCC samples based on its HPV infection status was obtained from the Gene Expression Omnibus (GEO) database. We comprehensively dissected the differences of genomic and tumour microenvironment (TME) immune cell infiltration landscapes between HPV + and HPV- VSCC. The potential molecular mechanisms of prognostic genes were explored by functional enrichment analysis. Five novel key molecules (SYCP2, SMC1B, RNF212, MAJIN and C14orf39) with significantly up-regulated expression in HPV + VSCC were identified while protein-protein interaction (PPI) networks were created upon Cytoscape software. Additionally, VSCC with up-regulated expression of these key molecules exhibited a significantly decreased TME immune cell infiltration. SYCP2 is overexpressed in HPV + VSCC and could be a candidate therapy target for further research.IMPACT STATEMENTWhat is already known on this subject? VSCC are characterised by two aetiological pathways. The former occurs in the background of lichen sclerosus, while the latter is related to HPV infection. VSCC most commonly arises from the non-HPV related pathway portends worse prognosis than VSCC derived from HPV infection.What do the results of this study add? Five key molecules are identified and significantly up-regulated in HPV + VSCC. In which, SYCP2 is overexpressed in HPV + VSCC and exhibited a significantly decreased TME immune cell infiltration. SYCP2 constant expression could be a potential biomarker of neoplasms associated with HPV and could be a candidate therapy target in VSCC especially HPV + VSCC for further research.What are the implications of these findings for clinical practice and/or further research? SYCP2 could be a candidate therapy target in VSCC especially with HPV + for further research.

Vulvar intraepithelial neoplasia, grade III, treated with photodynamic therapy: A case report

Vulvar intraepithelial neoplasia (VIN) is a precancerous lesion on the vulvar epidermis that does not invade or metastasize to surrounding stroma; it manifests as atypical intraepithelial hyperplasia on the vulva. Most patients with VIN are diagnosed early, and treatment with standardised therapy often leads to complete regression of symptoms. The treatment of VIN is still a challenge for clinicians because, in most cases, surgery is destructive and risky. However, photodynamic therapy (PDT) was recommended as a new treatment for VIN. Herein, we report the case of a patient with a large-area high-grade VIN lesion complicated by human papillomavirus infection. The patient could not undergo surgical treatment. However, treatment with PDT was performed in our outpatient department. There was slight pain during the treatment after multi-point injection of micro-lidocaine (0.05 mL/dot) was given. No recurrence was noted after 13 months of follow-up. More importantly, scarring and other major side effects were not detected. Therefore, PDT can be a useful alternative treatment for patients with VIN with large lesions or multifocal high-grade VIN.

Precursors, pathways of carcinogenesis and molecular markers of vulvar squamous cell carcinoma. Literature review

The review analyzes and summarizes the results of the studies on the pathogenesis of  vulvar squamous cell carcinoma and its diagnostic features, reviews precursors and  molecular subtypes of carcinomas. Despite the relatively low incidence of this tumor, over the past few decades, there has been an upward trend in its incidence, including the incidence among young women. According to the latest World Health Organization classification of lower genital tumors from 2020, vulvar squamous cell carcinoma is divided into human papillomavirus (HPV) associated and HPV-independent. While these carcinomas are often morphologically similar, their mechanisms of carcinogenesis, precursors, and clinical outcomes are different. Just the detection of virus DNA in a tumor is not enough to establish HPV status. Meanwhile immunohistochemical detection of the expression of p16 and p53 proteins allows not only to separate two pathogenetic pathways of carcinogenesis, but also to identify its molecular subtypes. The data on the possible use of p16 and p53 expression as the disease prognosis molecular markers have been obtained. Currently, the tactics of treatment and monitoring patients does not depend on the HPV status of carcinoma; however, the results of recent studies suggest that women with HPV positive vulvar cancer have significantly higher survival rates and a lower risk of recurrence. Understanding the mechanisms of carcinogenesis and improving its diagnosis will advance the assessment of the individual risk of the progression of precancerous lesions, as well as the outcome and the occurrence of tumor recurrence. 

The European Society of Gynaecological Oncology (ESGO), the International Society for the Study of Vulvovaginal Disease (ISSVD), the European College for the Study of Vulval Disease (ECSVD) and the European Federation for Colposcopy (EFC) consensus statements on pre-invasive vulvar lesions

The European Society of Gynaecological Oncology (ESGO), the International Society for the Study of Vulvovaginal Disease (ISSVD), the European College for the Study of Vulval Disease (ECSVD), and the European Federation for Colposcopy (EFC) developed consensus statements on pre-invasive vulvar lesions in order to improve the quality of care for patients with vulvar squamous intraepithelial neoplasia, vulvar Paget disease in situ, and melanoma in situ. For differentiated vulvar intraepithelial neoplasia (dVIN), an excisional procedure must always be adopted. For vulvar high-grade squamous intraepithelial lesion (VHSIL), both excisional procedures and ablative ones can be used. The latter can be considered for anatomy and function preservation and must be preceded by several representative biopsies to exclude malignancy. Medical treatment (imiquimod or cidofovir) can be considered for VHSIL. Recent studies favor an approach of using imiquimod in vulvar Paget's disease. Surgery must take into consideration that the extension of the disease is usually wider than what is evident in the skin. A 2 cm margin is usually considered necessary. A wide local excision with 1 cm free surgical margins is recommended for melanoma in situ. Following treatment of pre-invasive vulvar lesions, women should be seen on a regular basis for careful clinical assessment, including biopsy of any suspicious area. Follow-up should be modulated according to the risk of recurrence (type of lesion, patient age and immunological conditions, other associated lower genital tract lesions).

The European Society of Gynaecological Oncology (ESGO), the International Society for the Study of Vulvovaginal Disease (ISSVD), the European College for the Study of Vulval Disease (ECSVD) and the European Federation for Colposcopy (EFC) Consensus Statements on Pre-invasive Vulvar Lesions

ABSTRACT

The European Society of Gynaecological Oncology (ESGO), the International Society for the Study of Vulvovaginal Disease (ISSVD), the European College for the Study of Vulval Disease (ECSVD), and the European Federation for Colposcopy (EFC) developed consensus statements on pre-invasive vulvar lesions in order to improve the quality of care for patients with vulvar squamous intraepithelial neoplasia, vulvar Paget disease in situ, and melanoma in situ. For differentiated vulvar intraepithelial neoplasia (dVIN), an excisional procedure must always be adopted. For vulvar high-grade squamous intraepithelial lesion (VHSIL), both excisional procedures and ablative ones can be used. The latter can be considered for anatomy and function preservation and must be preceded by several representative biopsies to exclude malignancy. Medical treatment (imiquimod or cidofovir) can be considered for VHSIL. Recent studies favor an approach of using imiquimod in vulvar Paget's disease. Surgery must take into consideration that the extension of the disease is usually wider than what is evident in the skin. A 2 cm margin is usually considered necessary. A wide local excision with 1 cm free surgical margins is recommended for melanoma in situ. Following treatment of pre-invasive vulvar lesions, women should be seen on a regular basis for careful clinical assessment, including biopsy of any suspicious area. Follow-up should be modulated according to the risk of recurrence (type of lesion, patient age and immunological conditions, other associated lower genital tract lesions).

Assessment of recurrence rate and risk factors of relapse in stage in IA vulvar carcinoma

OBJECTIVE

To evaluate recurrence rates and risk factors of relapse in stage IA vulvar squamous cell carcinoma (VSCC) patients.

MATERIAL AND METHODS

Population-based prospectively collected data on stage IA VSCC was retrieved through the Danish Gynecological Cancer Database (DGCD) during 2011-2017. A central pathology review was performed on tumors from women with recurrent disease.

RESULTS

62 women diagnosed and treated for stage IA VSCC were identified. Nine (14.5%) of the included cases relapsed within the observation period. The recurrences were in the vulva, groins or both in 5 (8.1%), 3 (4.8%) and 1 (1.6%) of the women, respectively. At central pathology review, including all recurrent cases (n = 9), 5 out of 21 reviewed patients were upstaged to stage IB due to depth of invasion >1 mm and two were downstaged to Carcinoma in situ. Two of the upstaged women developed an isolated groin recurrence and one an isolated vulvar relapse. After exclusion of the seven cases the overall recurrence rate decreased to 10.9% (n = 6). Among these cases (n = 55) resection margin <8 mm and tumor size were associated with cancer recurrence.

CONCLUSION

Pathological assessment of stage IA VSCC (depth of invasion ≤1 mm) may be difficult. This may result in under-staging, which impact the choice of treatment and possibly the prognosis. This suggests a need for further clarification of the FIGO measurement and may require a more radical approach when it comes to treatment and groin exploration in stage IA VSCC. Resection margins <8 mm and tumor size were associated with relapse of the disease.

The Vulvar Cancer Risk in Differentiated Vulvar Intraepithelial Neoplasia: A Systematic Review

Differentiated vulvar intraepithelial neoplasia (dVIN) is the precursor of human papillomavirus (HPV)-independent vulvar squamous cell carcinoma (VSCC). Given the rare incidence of dVIN, limited information on the exact cancer risk is available. We systematically reviewed the primary and recurrent VSCC risk in patients with dVIN, as well as the time to cancer development. A systematic search was performed up to July 2021 according to the PRISMA guidelines. Five reviewers independently screened articles on title, abstract and full text, followed by critical appraisal of selected articles using the Quality in Prognostic Studies (QUIPS) tool. Of the 455 screened articles, 7 were included for analysis. The absolute risk for primary VSCC in dVIN varied between 33 and 86%, with a median time to progression to VSCC of 9–23 months. The risk of developing recurrent VSCC in dVIN associated VSCC was 32–94%, with a median time to recurrence of 13–32 months. In conclusion, patients with dVIN have a high risk of developing primary and recurrent VSCC with a short time to cancer progression. Increased awareness, timely recognition, aggressive treatment and close follow-up of HPV-independent vulvar conditions including dVIN is therefore strongly recommended.

Oral epithelial dysplasia: Recognition, grading and clinical significance

Histopathological grading of epithelial dysplasia remains the principal laboratory method for assessing the risk of malignant transformation in oral potentially malignant disorders (OPMDs). Current views on the molecular pathogenesis and histological interpretation of the features of epithelial dysplasia are described, and the use of grading systems for epithelial dysplasia is discussed. Changes to the current 2017 WHO criteria for diagnosis are proposed with emphasis on the architectural features of epithelial dysplasia. The predictive values of three-grade and binary systems are summarised, and categories of epithelial dysplasia are reviewed, including lichenoid and verrucous lesions, keratosis of unknown significance, HPV-associated dysplasia, differentiated and basaloid epithelial dysplasia. The implications of finding epithelial dysplasia in an oral biopsy for clinical management are discussed from the pathologists' viewpoint.

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.

Histological interpretation of differentiated vulvar intraepithelial neoplasia (dVIN) remains challenging-observations from a bi-national ring-study

Differentiated vulvar intraepithelial neoplasia (dVIN) is a premalignant lesion that is known to progress rapidly to invasive carcinoma. Accurate histological diagnosis is therefore crucial to allow appropriate treatment. To identify reliable diagnostic features, we evaluated the inter-observer agreement in the histological assessment of dVIN, among a bi-national, multi-institutional group of pathologists. Two investigators from Erasmus MC selected 36 hematoxylin-eosin-stained glass slides of dVIN and no-dysplasia, and prepared a list of 15 histological features of dVIN. Nine participating pathologists (i) diagnosed each slide as dVIN or no-dysplasia, (ii) indicated which features they used for the diagnosis, and (iii) rated these features in terms of their diagnostic usefulness. Diagnoses rendered by > 50% participants were taken as the consensus (gold standard). p53-immunohistochemistry (IHC) was performed for all cases, and the expression patterns were correlated with the consensus diagnoses. Kappa (ĸ)-statistics were computed to measure inter-observer agreements, and concordance of the p53-IHC patterns with the consensus diagnoses. For the diagnosis of dVIN, overall agreement was moderate (ĸ = 0.42), and pair-wise agreements ranged from slight (ĸ = 0.10) to substantial (ĸ = 0.73). Based on the levels of agreement and ratings of usefulness, the most helpful diagnostic features were parakeratosis, cobblestone appearance, chromatin abnormality, angulated nuclei, atypia discernable under × 100, and altered cellular alignment. p53-IHC patterns showed substantial concordance (ĸ = 0.67) with the consensus diagnoses. Histological interpretation of dVIN remains challenging with suboptimal inter-observer agreement. We identified the histological features that may facilitate the diagnosis of dVIN. For cases with a histological suspicion of dVIN, consensus-based pathological evaluation may improve the reliability of the diagnosis.

Interobserver reproducibility of the diagnosis of differentiated exophytic vulvar intraepithelial lesion (DEVIL) and the distinction from its mimics

AIMS

Most vulvar squamous cell carcinomas are human papillomavirus (HPV)-associated or TP53-mutant. A third category of HPV-independent TP53-wild-type lesions is uncommon and not fully understood. Differentiated exophytic vulvar intraepithelial lesion (DEVIL) has been characterised as a precursor of this latter category. The reproducibility of the diagnosis of DEVIL and its distinction from lesions with overlapping morphology has not been studied. Our aim was to establish the interobserver agreement in the diagnosis of DEVIL and its distinction from neoplastic and reactive conditions of the vulva on haematoxylin and eosin evaluation.

METHODS AND RESULTS

A set of 35 slides was evaluated by eight reviewers (two trainees and six practising gynaecological pathologists). The set included DEVIL, condyloma, established vulvar precursors [high-grade squamous intraepithelial lesion (HSIL) and differentiated vulvar intraepithelial neoplasia (dVIN)] with superimposed acanthosis or verruciform growth, lichen simplex chronicus (LSC), and psoriasis. Kappa (κ) values were calculated. Overall, interobserver agreement was moderate (κ = 0.56), improving to substantial (κ = 0.7) when evaluation was performed by practising pathologists. Agreement was strong for the diagnosis of HSIL (κ = 0.88), and substantial for the diagnosis of DEVIL (κ = 0.61), condyloma (κ = 0.79), and LSC (κ = 0.72). Agreement was moderate for the diagnosis of dVIN (κ = 0.59) and psoriasis (κ = 0.53). Perfect agreement (6/6) among practising pathologists was observed in 43% of cases, and majority agreement (5/6 or 4/6) was observed in 48% of cases.

CONCLUSIONS

Reproducibility in the diagnosis of verruciform vulvar lesions, including the novel DEVIL, is acceptable overall. Reproducibility is higher for well-known lesions such as HSIL and condyloma than for more challenging diagnoses such as DEVIL, dVIN, and psoriasis. Agreement is higher among practising gynaecological pathologists, suggesting that training and experience improve reproducibility. Our findings support the inclusion of DEVIL as a diagnostic entity in the classification of vulvar squamous lesions.

Evaluation of Immunohistochemical Markers, CK17 and SOX2, as Adjuncts to p53 for the Diagnosis of Differentiated Vulvar Intraepithelial Neoplasia (dVIN)

Histological diagnosis of differentiated vulvar intraepithelial neoplasia (dVIN), the precursor of human papillomavirus (HPV)-independent vulvar squamous cell carcinoma (VSCC), can be challenging, as features of dVIN may mimic those of non-dysplastic dermatoses. To aid the diagnosis, p53-immunohistochemistry (IHC) is commonly used, and mutant expression patterns are used to support a histological diagnosis of dVIN. However, a proportion of dVIN can show wild-type p53-expression, which is characteristic of non-dysplastic dermatoses. Furthermore, recent research has identified a novel precursor of HPV-independent VSCC—the p53-wild-type differentiated exophytic vulvar intraepithelial lesion (de-VIL). Currently, there are no established diagnostic IHC-markers for p53-wild-type dVIN or de-VIL. We evaluated IHC-markers, cytokeratin 17 (CK17), and SRY-box 2 (SOX2), as diagnostic adjuncts for dVIN. For this, IHC-expression of CK17, SOX2, and p53 was studied in dVIN (n = 56), de-VIL (n = 8), and non-dysplastic vulvar tissues (n = 46). For CK17 and SOX2, the percentage of cells showing expression, and the intensity and distribution of expression were recorded. We also performed next generation targeted sequencing (NGTS) on a subset of dVIN (n = 8) and de-VIL (n = 8). With p53-IHC, 74% of dVIN showed mutant patterns and 26% showed wild-type expression. Median percentage of cells expressing CK17 or SOX2 was significantly higher in dVIN (p53-mutant or p53-wild-type) and de-VIL than in non-dysplastic tissues (p < 0.01). Diffuse, moderate-to-strong, full epithelial expression of CK17 or SOX2 was highly specific for dVIN and de-VIL. With NGTS, TP53 mutations were detected in both dVIN and de-VIL. We infer that immunohistochemical markers CK17 and SOX2, when used along with p53, may help support the histological diagnosis of dVIN.

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.

Does HPV infection have impact on results of photodynamic treatment of vulvar lichen sclerosus?

BACKGROUND

The association between lichen sclerosus (LS) and human papilloma virus (HPV) infections remains unclear. The co-occurrence of both pathologies may impact treatment and prognosis. This study aimed to assess the results of photodynamic therapy (PDT) for vulvar LS and the effect of incidence of HPV infection on the results of treatment and duration of remission.

METHODS

A total of 73 patients with LS were included in the study. In each patient, 14 types of HPV were detected. PDT was performed using the PhotoDyn 501, which emits light at 630 nm wavelength and power density of 204 mW/cm². Focal lesions were exposed for 10 min once weekly for a total of 10 weeks. The complete treatment cycle was repeated after 3 months, whenever required. The biopsy was repeated after completion of treatment.

RESULTS

The number of treatment cycles for HPV-positive and HPV-negative patients were not statistically different (cases after one or two PDT cycles). An exception was a group of patients with LS requiring three PDT cycles. Analysis of remission period considering HPV results (positive vs. negative) did not reveal a significant statistical difference. Mean remission period among HPV-negative patients was longer in comparison to remission time for those with positive HPV results (14 ± 9 vs. 11 ± 9 months).

CONCLUSIONS

PDT may be a promising, effective, and safe method for the treatment of LS regardless of HPV infection.

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.

Putative precancerous lesions of vulvar squamous cell carcinoma

Precursor lesions of vulvar squamous cell carcinoma (VSCC) can be divided into two major biologic and prognostic groups: HPV-associated and HPV-independent VSCC. These two pathways are categorized as usual vulvar intraepithelial neoplasia (uVIN) with progression to basaloid or warty VSCC and differentiated vulvar intraepithelial neoplasia (dVIN) with progression to the more common keratinizing VSCC. While the HPV-dependent pathway to squamous cell carcinoma is well-understood, the development of squamous cell carcinoma from HPV-independent lesions is less clear. The majority of HPV-independent lesions fall into the dVIN category, and mutations in TP53 have been implicated as the driver behind their development. Other less common HPV-independent precursor lesions, termed differentiated exophytic vulvar intraepithelial lesion (DEVIL) and vulvar acanthosis with altered differentiation (VAAD), have also been characterized as precursors to keratinizing and verrucous VSCC. Inflammatory conditions of the vulva such as lichen sclerosus and lichen simplex chronicus also put patients at risk for developing VSCC. We herein evaluate the available evidence and biologic basis for these VSCC precursor lesions, among other speculated entities, and discuss their clinical, diagnostic, and prognostic features.

Vulvar intraepithelial neoplasia: Incidence and long-term risk of vulvar squamous cell carcinoma

The risk of vulvar squamous cell carcinoma (VSCC) in patients with high-grade vulvar intraepithelial neoplasia (VIN) is considered lower in high-grade squamous intraepithelial lesion (HSIL) compared to differentiated VIN (dVIN), but studies are limited. Our study investigated both the incidence of high-grade VIN and the cumulative incidence of VSCC in patients with HSIL and dVIN separately. A database of women diagnosed with high-grade VIN between 1991 and 2011 was constructed with data from the Dutch Pathology Registry (PALGA). The European standardized incidence rate (ESR) and VSCC risk were calculated, stratified for HSIL and dVIN. The effects of type of VIN (HSIL vs dVIN), age and lichen sclerosis (LS) were estimated by Cox regression. In total, 1148 patients were diagnosed with high-grade VIN between 1991 and 2011. Between 1991-1995 and 2006-2011, the ESR of HSIL increased from 2.39 (per 100 000 woman-years) to 3.26 and the ESR of dVIN increased from 0.02 to 0.08. The 10-year cumulative VSCC risk was 10.3%; 9.7% for HSIL and 50.0% for dVIN (log rank P < .001). Type of VIN, age and presence of LS were independent risk factors for progression to VSCC, with hazard ratios of 3.0 (95% confidence interval [CI] 1.3-7.1), 2.3 (95% CI 1.5-3.4) and 3.1 (95% CI 1.8-5.3), respectively. The incidence of high-grade VIN is rising. Because of the high cancer risk in patients with dVIN, better identification and timely recognition are urgently needed.

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.

New Directions in Vulvar Cancer Pathology

PURPOSE OF REVIEW

The aim of this article is to provide clinicians and pathologists with an understanding of the aetiopathology, pathogenesis and classification of vulval neoplasia and their molecular correlates.

RECENT FINDINGS

There is an increased understanding of subcellular changes in vulvar malignancies. These provide the direction for further research and aid personalised treatment for patients. The article explores concepts of the aetiology of vulvar cancer and updates the reader with the equivalence of terminology of preneoplastic vulval disease. The differential diagnosis of squamous neoplasia and their clinicopathological correlation is detailed. The salient findings from recent literature into the understanding of the disease of squamous cell neoplasia and rare vulvar malignancies are summarised.