Squamous Vulvar Intraepithelial Neoplasia

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.

Biomarker Expression in Multifocal Vulvar High-Grade Squamous Intraepithelial Lesions

Simple Summary

In this exploratory study, we aimed to compare biomarker profiles in patients with multiple high-risk human papillomavirus (HPV)-associated vulvar precursor lesions, which is called multifocal high-grade squamous intraepithelial lesion (HSIL). The HPV-positive HSILs were tested for HPV genotype, expression of two immunohistochemical markers p16^INK4a and Ki-67, and DNA methylation of six genes. Generally, the biomarkers showed similar expression between lesions. Occasionally, marked differences were observed, indicating that not all multifocal lesions are the same. Our study contributes to a better understanding of the value of potential diagnostic, prognostic, and predictive biomarkers in patients with vulvar multifocal HSIL. Validation in larger cohorts will be important.

Abstract

In patients with high-grade squamous intraepithelial lesion (HSIL) of the vulva, the presence of multiple lesions, called multifocal HSIL, is common. The aim of this exploratory study was to investigate biomarker expression profiles in multifocal HSIL. In total, 27 lesions from 12 patients with high-risk human papillomavirus (HPV)-positive multifocal HSIL were tested for HPV genotype, expression of p16^INK4a and Ki-67, and DNA methylation of six genes. HPV16 was found most commonly in 21 (77.8%) HSILs. In two (16.4%) patients, HPV genotype differed between the lesions. All lesions demonstrated diffuse p16^INK4a staining, of which three (11.1%) were combined with patchy staining. One patient (8.3%) demonstrated markedly different DNA methylation levels between lesions. Generally, heterogeneity in methylation profiles was observed between different patients, even when other biomarkers showed similar expression. In conclusion, this study is the first to demonstrate heterogeneity of individual lesions in patients with multifocal HSIL. The studied biomarkers have the potential to refine prognostic and predictive diagnostics. Future prospective, longitudinal studies are needed to further explore the potential of a biomarker profile for management of patients with multifocal HSIL.

Cancer of the Vulva: A Review

BACKGROUND

Vulvar cancers, although rare, are becoming an increasingly serious threat to women's health. Cancer of the vulva accounted for 0.3% of all new cancers in the United States in 2019, with 6,070 newly diagnosed cases. This review details the epidemiology, pathogenesis, diagnosis, staging, and treatment of vulvar malignancies.

OBJECTIVE

To review cancer entities of the vulva, including vulvar intraepithelial neoplasms, squamous cell carcinoma (SCC), malignant melanoma, basal cell carcinoma, neuroendocrine tumors, and adenocarcinomas.

MATERIALS AND METHODS

Literature review using PubMed search for articles related to cancer of the vulva.

RESULTS

Vulvar intraepithelial neoplasms represent premalignant precursors to SCC of the vulva. There are several different histopathologic subtypes of SCC, and treatment is dependent on characteristics of primary tumor and lymph node involvement. Melanoma is the second most common cancer to affect the vulva, and staging is based on tumor, node, and metastatic spread.

CONCLUSION

Vulvar malignancies are rare, and diagnosis is dependent on biopsy and pathologic evaluation. Treatment for vulvar malignancies depends on histopathologic diagnosis but ranges from wide local excision with or without lymph node biopsy or dissection to radiation therapy with chemo- or immunotherapy. Overall survival varies by diagnosis.

Photodynamic therapy for vulvar leukoplakia

The aim of study is to evaluate the tolerability and effectiveness of photodynamic therapy as an organ‑preserving treatment in patients with vulvar leukoplakia. 50 patients with a verifed diagnosis of «vulvar leukoplakia» were included in the study. The age varied from 27 to 74 years. The method of treatment assumed the use of the photosensitizer рhotolon (RUE «Belmedpreparaty», Belarus) administered intravenously in doses of 1.8–2.5 mg/kg. Photoirradiation of pathological foci was carried out 2.5–3 hours after intravenous injection of photolon® using a semiconductor laser «UPL PDT» (LEMT, Belarus, λ=661 nm) at exposure doses from 30 to 100 J/cm2 with a power density of 100–170 mW/cm2. The treatment was performed under medical anesthesia. The results of treatment were evaluated using clinical data. Adverse reactions and complications after the introduction of the photosensitizer and photoirradiation have not been observed. Complete clinical regression of the treated pathological foci was noted in 100% of cases with a follow‑up observation 1 month after the treatment. At follow‑up after 3 months, local recurrences of the disease were detected in 4 cases, which were successfully treated with repeated photo‑dynamic therapy sessions. The percentage of complete regressions was 92%, partial – 8%. The obtained results allow judging on the possibility of using photodynamic therapy in the treatment of patients with vulvar leukoplakia, which allows to preserve the organ and obtain a satisfactory functional and cosmetic result.

Impact of smoking on imiquimod response in patients with vulval intraepithelial neoplasia

BACKGROUND

Vulval intraepithelial neoplasia (VIN) is a precancerous condition that may progress to invasive malignancy. VIN is associated with human papillomavirus (HPV) infection in most cases, and with inflammatory skin disorders in a smaller proportion of patients. Treatment of VIN has traditionally been surgical excision; however, topical treatments, including imiquimod cream, are becoming increasingly used. Patient factors influencing response to imiquimod therapy, in particular smoking, have not yet been published.

AIM

To assess the impact of smoking and other patient characteristics that may influence the treatment response to topical imiquimod for VIN.

METHODS

This was a retrospective cohort study of 46 women treated with topical imiquimod for VIN in a single centre dermatology unit from January 2011 to July 2017.

RESULTS

Complete clinical resolution of VIN was observed in 28 of 46 patients (61%), but was significantly reduced in the smoking cohort.

CONCLUSIONS

Smoking may impair response to imiquimod for VIN, and should be considered when discussing VIN treatment options with patients.

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.

Papillomavirus genotyping on formaldehyde fixed paraffin-embedded tissues in vulvar intraepithelial neoplasia

PURPOSE

Few studies have described the epidemiology of human papillomavirus (HPV) in vulvar intraepithelial neoplasia (VIN). The aim of this study was to genotype HPV on formalin fixed paraffin-embedded tissues in VIN lesions.

METHODS

A 5-year retrospective study was conducted by including all patients attending the teaching hospital of Nice with a diagnosis of VIN between 1st January 2010 and 31st December 2014. For all patients, HPV genotyping was performed with the PapilloCheck^® microarray kit, routinely used on cervical cytology samples, and optimized for formaldehyde fixed paraffin-embedded tissues in VIN.

RESULTS

Forty patients were included in the study: 39 patients had usual VIN and one presented with differentiated VIN. Among the 39 patients with usual VIN, the prevalence of HPV was 90% (35/39). Thirty-two patients had high grade VIN (82%) and seven low grade VIN (18%). In high grade VIN, the most represented HPV types were: HPV 16 (21/32 66%), HPV 56 (3/32 9%) and HPV 33 (2/32 6%). In low grade VIN, the most represented HPV types were: HPV 16 (4/7 57%) and HPV 6 (3/7 43%). Interestingly, 5/39 (13%) of patients diagnosed with usual VIN also had co-existing lichen sclerosus.

CONCLUSIONS

We have optimized a HPV genotyping technique, routinely used on cervical cytology samples, and on paraffin fixed embedded tissue showing VIN. Moreover, we have identified five patients with lichen sclerosus co-existing with usual VIN. This association has rarely been reported and proves that these two entities can coexist.

The Natural History of Vulvar Intraepithelial Neoplasia, Differentiated Type: Evidence for Progression and Diagnostic Challenges

Squamous cell carcinoma of the vulva (SCCV) develops through either human papillomavirus (HPV)-dependent or HPV-independent pathways. Approximately 60% of SCCV arise independently of HPV, commonly in a background of an inflammatory dermatosis, particularly lichen sclerosus. The likely direct precursor to most of these lesions is vulvar intraepithelial neoplasia (VIN), differentiated type (dVIN), although the evidence is largely circumstantial. There are few reports of progression to carcinoma, and the natural history of this pathway is not well understood. Nevertheless, dVIN is widely regarded as a potentially aggressive lesion. We identified dVIN adjacent to SCCV in 97 of 212 women (45.8%). Twenty-four of the 97 women (24.7%) had biopsies performed at least 6 mo before presentation with SCCV; slides for 47 biopsies from 21 women were available for review. dVIN was identified in 18 biopsies from 8 women (38.1%), which in 14 biopsies had been previously unrecognized. The subsequent cancer developed in the same region as the previous biopsy showing dVIN in 6 of the 8 women. The median interval between biopsy and invasive cancer was 43.5 mo (range, 8-102 mo). dVIN-associated SCCV was strongly associated with both lichen sclerosus, and HPV-negative status compared with usual type VIN (relative risk=38.35 (9.755-150.8) and 0.06485 (0.02764-0.1522), respectively). This study adds to the evidence linking dVIN with SCCV, and indicates that both clinical and histologic underrecognition contribute to the apparent rarity of dVIN as a solitary diagnosis. The morphologic spectrum of dVIN is likely to be wider than commonly appreciated; however, histologically defining the lower threshold is difficult and controversial.

Efficacy of 5% imiquimod cream on vulvar intraepithelial neoplasia in Korea: pilot study

Background

Various therapeutic options, including surgery, electrocautery, cryotherapy, 5-fluorouracil treatment, laser therapy, radiotherapy, photodynamic therapy, and interferon-α/γ injection, have been employed to treat vulvar intraepithelial neoplasia (VIN) with varying degrees of success. To truly cure VIN, human papillomavirus elimination is considered important.

Objective

To investigate the efficacy of 5% imiquimod cream used to treat VIN in Korean patients

Methods

We performed a prospective, uncontrolled, observational study. Nine patients with histologically confirmed VIN applied 5% imiquimod cream to their vulvar lesions three to five times a week until a clinical response was apparent. All lesions were photo-documented, and therapeutic efficacy was assessed in terms of local adverse effects lesion number, size, and hyperpigmentation.

Results

The mean treatment duration was 30.2 months, and the median follow-up period after therapy completion was 30 months. Of the nine patients recruited, six (66.6%) experienced complete responses (CR) or partial responses (PR). Hyperpigmented patches in the VIN lesions were evident in five subjects (55.6%), and all experienced either CR or PR. Only three patients (33.3%) suffered from local adverse effects, which were relieved after temporary suspension of therapy, and better outcomes were attained ultimately.

Conclusion

The imiquimod cream was more efficacious when used to treat VIN of the hyperpigmented type compared with lesions lacking pigmentation. The unifocal nature of a lesion and the development of local adverse effects are useful factors when imiquimod cream is prescribed. However, although the cream is convenient and effective, regional resistance may develop, and close follow-up is essential because VIN may become malignant.

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.

Interobserver variability and the effect of education in the histopathological diagnosis of differentiated vulvar intraepithelial neoplasia

No published data concerning intraobserver and interobserver variability in the histopathological diagnosis of differentiated vulvar intraepithelial neoplasia (DVIN) are available, although it is widely accepted to be a subtle and difficult histopathological diagnosis. In this study, the reproducibility of the histopathological diagnosis of DVIN is evaluated. Furthermore, we investigated the possible improvement of the reproducibility after providing guidelines with histological characteristics and tried to identify histological characteristics that are most important in the recognition of DVIN. A total number of 34 hematoxylin and eosin-stained slides were included in this study and were analyzed by six pathologists each with a different level of education. Slides were reviewed before and after studying a guideline with histological characteristics of DVIN. Kappa statistics were used to compare the interobserver variability. Pathologists with a substantial agreement were asked to rank items by usefulness in the recognition of DVIN. The interobserver agreement during the first session varied between 0.08 and 0.54, which slightly increased during the second session toward an agreement between -0.01 and 0.75. Pathologists specialized in gynecopathology reached a substantial agreement (kappa 0.75). The top five of criteria indicated to be the most useful in the diagnosis of DVIN included: atypical mitosis in the basal layer, basal cellular atypia, dyskeratosis, prominent nucleoli and elongation and anastomosis of rete ridges. In conclusion, the histopathological diagnosis of DVIN is difficult, which is expressed by low interobserver agreement. Only in experienced pathologists with training in gynecopathology, kappa values reached a substantial agreement after providing strict guidelines. Therefore, it should be considered that specimens with an unclear diagnosis and/or clinical suspicion for DVIN should be revised by a pathologist specialized in gynecopathology. When adhering to suggested criteria the diagnosis of DVIN can be made easier.

Management of precancerous lesions prior to conception and during pregnancy: a narrative review of the literature

Special considerations aiming at preserving reproductive function have to be implemented when treating young patients with precancerous lesions of the lower genital tract. These high-grade lesions may progress into invasive cancer if left untreated. Currently, there are limited data on the impact of vulvar and vaginal precancerous lesions on fertility and its management during pregnancy. However, management and outcomes for cervical lesions have been extensively reported. The main approach for vulvar and vaginal lesions are maintaining anatomical function and cosmetics; whereas, treatment options for cervical precancerous lesions range from observation, cryotherapy or the more aggressive conisation. Gestational age is the most important factor in determining expectant management or surgical intervention. This narrative review draws attention to the relevant aspects of precancerous lesions of the lower genital tract, the potential effects and management prior to conception and during pregnancy.

Screening and follow up of vulval skin disorders

Vulval squamous cell carcinoma is relatively rare; however, up to 20% of women have significant vulval symptoms during their lifetime. Formal screening programmes for vulval disease have not been established. The evidence for the use of vulval cytology and vulvoscopy is reviewed. No randomised-controlled trials have compared follow-up regimens, and although a few consensus documents have been published, formal guidelines are lacking in Grade A evidence. With increasing pressure on healthcare resources, the possibility of identifying high-risk groups to optimise the use of follow up in specialist clinics is explored. Vulval disease is uncommon and there is no evidence that screening would decrease incidence. If high-risk groups can be identified, follow up should take place in specialised vulval clinics with experienced clinicians who are trained in vulval disease. Women with uncomplicated vulval conditions should be discharged to patient-initiated follow up or primary care. Central to the reduction of mortality and morbidity is increased awareness of vulval conditions among women and improved education of healthcare professionals, with particular understanding of the importance of physical examination.

Treatment of vulvar intraepithelial neoplasia with topical imiquimod: seven years median follow-up of a randomized clinical trial

OBJECTIVE

Recently we reported on the efficacy of imiquimod for treating vulvar intraepithelial neoplasia (VIN) in a placebo-controlled, double-blinded randomized clinical trial (RCT). Four weeks after treatment, a complete response was observed in 35% of patients and a partial response in 46%. All complete responders remained disease-free at 12 months follow-up. In the current investigations, we assessed long-term follow-up at least 5 years after the initial RCT.

METHODS

Twenty-four of 26 imiquimod-treated patients who had participated in the initial RCT were seen for follow-up. Primary endpoint was durability of clinical response to imiquimod assessed by naked eye vulvar examination and histology. Long-term clinical response was correlated to lesion size before start of the initial RCT. Secondary endpoints were mental health, global quality of life, body image and sexual function in relation with long-term clinical response.

RESULTS

Median follow-up period was 7.2 years (range 5.6-8.3 years). VIN recurred in one of nine complete responders. Of the initial partial responders, two became disease-free after additional imiquimod treatment. In the other partial responders, VIN recurred at least once after the initial RCT. In long-term complete responders, lesion size at study entry was smaller and these patients had a significantly better global quality of life at follow-up than patients with residual disease and/or recurrence after imiquimod treatment.

CONCLUSIONS

In case of a complete response, imiquimod is effective in the long-term. Furthermore, patients with a long-term complete response had a significantly better global quality of life than patients who recurred after imiquimod treatment.

Vulval Disease in the Postmenopausal Patient: A Guide to Current Management

In spite of overwhelming evidence that vulvovaginal symptoms plague up to 46% of menopausal and perimenopausal women, and that there persists a reluctance to seek help among patients, adequate vulval and sexual histories are still woefully rare in general gynaecology clinics. This review aims to present the key points of an effective vulval history and an overview of the accepted current management of vulval disease postmenopause, in order that our patients feel encouraged to present with their problems.

Two distinct pathways to development of squamous cell carcinoma of the vulva

Squamous cell carcinoma (SCC) accounts for approximately 95% of the malignant tumors of the vaginal vulva and is mostly found in elderly women. The future numbers of patients with vulvar SCC is expected to rise, mainly because of the proportional increase in the average age of the general population. Two different pathways for vulvar SCC have been put forth. The first pathway is triggered by infection with a high-risk-type Human Papillomavirus (HPV). Integration of the HPV DNA into the host genome leads to the development of a typical vulvar intraepithelial neoplasia (VIN), accompanied with overexpression of p14^ARF and p16^INK4A. This lesion subsequently forms a warty- or basaloid-type SCC. The HPV vaccine is a promising new tool for prevention of this HPV related SCC of the vulva. The second pathway is HPV-independent. Keratinizing SCC develops within a background of lichen sclerosus (LS) through a differentiated VIN. It has a different set of genetic alterations than those in the first pathway, including p53 mutations, allelic imbalances (AI), and microsatellite instability (MSI). Further clinical and basic research is still required to understand and prevent vulvar SCC. Capsule. Two pathway for pathogenesis of squamous cell carcinoma of the value are reviewed.

Skinning clitorectomy and skin replacement in women with vulvar intra-epithelial neoplasia

BACKGROUND AND AIM

Partial or total clitoris amputation for vulvar intra-epithelial neoplasia (VIN) affects quality of life and sexual function and is likely to constitute over-treatment as superficial excision of only the involved, thinly cornified, stratified squamous clitoral epithelium would suffice. For this reason, we applied skinning clitorectomy and replacement of clitoral skin as an organ-sparing surgical therapy for clitoral VIN.

METHODS

Seven consecutive patients presenting with VIN were treated from July 2003 to February 2008. The skin of the glans clitoridis was resected from the underlying spongious tissue by combined hydro-dissection and sharp dissection. The spongiosum was subsequently covered with either a thin skin flap from the inner aspect of the remaining preputium or minor labium, or a split-thickness skin graft taken from the proximal inner aspect of the thigh.

RESULTS

In all patients, the preoperative diagnosis of VIN was confirmed histopathologically. Additionally, micro-invasive carcinoma was found in two. The postoperative course was complicated by haematoma in one patient and a superficial infection in another, but these did not influence the overall satisfactory outcome obtained in all patients. Preoperative sexual function was largely preserved and, after a mean follow-up of 21 months, no recurrence or invasion of the original lesion was observed in any of the patients.

CONCLUSION

We advocate skinning clitorectomy and replacement of its skin as a sound organ-sparing alternative for clitoral amputation in the treatment of clitoral VIN.

Vulvar intraepithelial neoplasia—The need for auditable measures of management

OBJECTIVES

Surgical excision is currently the standard treatment for vulvar intraepithelial neoplasia (VIN). To date it has proved difficult to evaluate the management of VIN in reported series due to heterogeneity in datasets. The objective of this study was to justify standardised data presentation to permit comparison between series and facilitate determination of an optimal strategy for management of VIN. We propose auditable indicators of performance to benchmark management and outcomes. This may also enable definition of a surgical control arm for future novel therapy studies.

STUDY DESIGN

Data from the Northern Gynaecological Oncology Centre (NGOC), UK on women with proven VIN diagnosed between 1989 and 2004 who attended the vulvar review clinic are presented and analysed alongside three large retrospective series by Jones et al. [Jones RW, Rowan DM, Stewart AW. Vulvar intraepithelial neoplasia: aspects of the natural history and outcome in 405 women. Obstet Gynecol 2005;106(6):1319-26], Herod et al. [Herod JJ, Shafi MI, Rollason TP, Jordan JA, Luesley DM. Vulvar intraepithelial neoplasia: long term follow up of treated and untreated women. Br J Obstet Gynaecol 1996;103(5):446-52], McNally et al. [McNally OM, Mulvany NJ, Pagano R, Quinn MA, Rome RM. VIN 3: a clinicopathologic review. Int J Gynecol Cancer 2002;12(5):490-5] against proposed performance indicators to illustrate the deficiencies in current data presentation.

RESULTS

Demographics and indicators such as degree of pathological expertise, definition of early stromal invasion and use of International Society for the study of Vulvovaginal Disease (ISSVD) classification were usually well documented. The description of lesions including size and focality were not always documented, nor the proportion examined by co-specialists. Numbers of primary treatments were well described but the indications for treatment, completeness of excision and VIN subclassification were not. Subsequent surgical treatments were inconsistently reported including the pathological details and intervals between treatments. Symptomatology was not well reported. Information on follow-up intervals and duration of follow-up with an indication of patient compliance was inadequate. Outcome data on recurrence of VIN and progression to carcinoma (early stromal invasion or frankly invasive carcinoma) were included in all series.

CONCLUSIONS

Consensus on the ideal management of VIN or evaluation of new strategies will prove impossible without standardised data presentation. We propose a number of performance indicators that will facilitate evaluation of future studies or series against the current benchmark of surgical treatment for VIN.

MIB1 expression in basal cell layer: a diagnostic tool to identify premalignancies of the vulva

Lichen sclerosus, high-grade usual vulvar intraepithelial neoplasia (VIN) and differentiated VIN have a different malignant potential. The objective of this study was to quantify the proliferative activity in the basal region of the epithelium of vulvar premalignancies. Furthermore, we investigated whether MIB1 expression in the basal region of vulvar epithelium can be helpful in diagnosing differentiated VIN, which may be hard to discern from normal epithelium. MIB1 was used to immunohistochemically visualise proliferating cells within formalin-fixed, paraffin-embedded, archival tissue sections of different vulvar premalignancies (N=48) and normal vulvar epithelium (N=16). Automatic digital image analysis software was developed to quantify the proliferating fraction in different parts of the epithelium (MIB1 positivity index). MIB1 expression differed among the various vulvar premalignancies; a MIB1-negative basal cell layer was a distinct feature of normal vulvar epithelium. No MIB1-negative basal cell layer was noted in differentiated VIN or other vulvar premalignancies. Owing to this negative cell layer, the MIB1 proliferation index in normal vulvar epithelium was significantly lower than in vulvar premalignancies. In conclusion, MIB1 expression can be a helpful tool in diagnosing a premalignancy and has additional value especially to distinguish differentiated VIN neoplasia from normal vulvar epithelium, but cannot explain the differences in malignant potential.