Possible etiologic heterogeneity of vulvar intraepithelial neoplasia. A correlation of pathologic characteristics with human papillomavirus detection by in situ hybridization and polymerase chain reaction

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.

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.

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.

Detection of Merkel cell virus and correlation with histologic presence of Merkel cell carcinoma in sentinel lymph nodes

Background:

Adjuvant treatment can dramatically improve the survival of patients with metastatic Merkel cell carcinoma (MCC), making early, accurate detection of nodal disease critical. The purpose of this study was to correlate Merkel cell virus (MCV) detection with histopathologic disease in sentinel lymph nodes (SLNs) of MCC.

Methods:

Merkel cell carcinoma cases with SLN (n=25) were compared with negative controls (n=27). Viral load was obtained by quantitative polymerase chain reaction (PCR) for regions VP1 and LT3 of MCV. Histopathologic disease and viral load were correlated.

Results:

Merkel cell virus was detected in 16 out of 17 (94%) of primary MCC (mean viral load (MVL)=1.44 copies per genome). Viral load in the negative controls was <0.01 copies per genome. Merkel cell carcinoma was present in 5 out of 25 (20%) SLN by histopathology, and MCV was detected in 11 out of 25 (44%) MCC SLN (MVL=1.68 copies per genome). In all, 15 out of 25 (60%) SLN showed correlation between histologic and MCV results. In all, 2 out of 25 (8%) samples were histopathologically positive and PCR negative. Of note, 8 out of 25 (32%) samples had detectable MCV without microscopic disease.

Conclusion:

Patients with positive SLN for MCV even if negative by histopathology were identified. The application of molecular techniques to detect subhistologic disease in SLN of MCC patients may identify a subset of patients who would benefit from adjuvant nodal treatment.

Patients with usual vulvar intraepithelial neoplasia-related vulvar cancer have an increased risk of cervical abnormalities

Background:

Vulvar squamous cell carcinoma (SCC) originates the following two pathways, related to differentiated (d) vulvar intraepithelial neoplasia (VIN) or to human papillomavirus (HPV)-related usual (u) VIN. Multicentric HPV infections (cervix, vagina and vulva) are common. We hypothesise that patients with a uVIN-related vulvar SCC more often have cervical high-grade squamous intraepithelial lesions (HSILs) compared with women with dVIN-related vulvar SCC.

Methods:

All vulvar SCCs (201) were classified to be dVIN- (n=164) or uVIN related (n=37). Data with regard to the smear history and cervical histology were retrieved from PALGA, the nationwide Netherlands database of histo- and cytopathology. For HSIL cervical smears of which histology was taken, HPV DNA analysis on both the vulvar and cervical specimens was performed.

Results:

At least one smear was available in 145 (72%) of the 201 patients. Patients with a uVIN-related vulvar SCC more often had an HSIL compared with patients with a dVIN-related SCC (35 vs 2%, P<0.001). A total of 10 of the 13 HSILs were histologically assessed and identical HPV types were found in the vulva and cervix.

Conclusion:

These data emphasise the necessity to differentiate between dVIN- and uVIN-related vulvar tumours and to examine the entire lower female ano-genital tract once an uVIN-related lesion is found.

Comprehensive analysis of 130 multicentric intraepithelial female lower genital tract lesions by HPV typing and p16 expression profile

PURPOSE

HPV associated cervical transformation is characterized by well-defined steps, including persistent HPV infection and deregulated oncogene expression. Recent studies have suggested that a number of lower genital tract lesions are clonally related to cervical lesions. In the current study, HPV infections and oncogene expression were assessed in a large series of patients with multicentric lower genital tract disease to analyze the transformation steps in extracervical disease.

METHODS

One hundred and thirty biopsies of 52 women treated for multicentric synchronous or metachronous lower genital tract intraepithelial neoplasias were collected. Up to seven multicentric specimens taken from one patient were studied with a maximum follow up of 20 years. HPV typing and p16(ink4a) immunostaining was performed.

RESULTS

HPV DNA was present in 121 of 130 specimens (93%). HPV16 was frequently found in VIN, VaIN and AIN (73, 60 and 77%, respectively), whereas only 37% of CIN were HPV16 positive. Infections with identical HPV types in multicentric lesions were diagnosed in 46% of the HPV positive patients. p16INK4a expression was negative in the nine HPV negative lesions whereas about 90% of the high grade lesions showed diffuse p16 staining.

CONCLUSION

Our findings indicate that multicentric lower genital tract disease evolves through different pathways. Some cases were related to a high susceptibility towards HPV infections, while others exhibited features of clonal propagation of transformed cervical cell clones. The clinical management of the latter group is particularly challenging, because malignant cell clones can persist over a long time course.

Integration of HPV-16 and HPV-18 DNA in vulvar intraepithelial neoplasia

OBJECTIVE

Vulvar intraepithelial neoplasia (VIN) is a premalignant disease of the lower genital tract. The increased occurrence of high-risk human papillomavirus (HPV) infection seems to be associated with the increasing frequency of VIN. Integration of HPV DNA into host chromosome has been hypothesized to be a critical step in the carcinogenesis of cervical neoplasia resulting in altered expression of two viral transforming genes E6 and E7.

METHOD

We analyzed HPV-16 and HPV-18 DNA, and integrated transcripts of HPV-16 and HPV-18 genomes in 30 VIN cases with 53 lesions using a PCR-based protocol for the amplification of papillomavirus oncogene transcripts (APOT).

RESULT

24 of 30 VIN lesions (80%) harbored HPV-16 (in 23 cases) and HPV-18 DNA. Integration of HPV-16 and HPV-18 genome was observed in eight (38.1%) of 21 HPV-16/18 positive VIN III cases. All eight VIN were multifocal and had multicentric disease (CIN/VAIN) including one case that progressed to vulvar carcinoma. Five of eight lesions were found to have E7 specific viral-cellular fusion transcripts only, two of eight showed E7-E4 viral-cellular fusion transcripts, and one of eight had both episomally derived and E7-E4 viral-cellular fusion transcripts. In 10 (83.3%) of 12 multifocal VIN III patients, all specimens derived from the same patient harbored the same HPV type and HPV transcript pattern suggesting monoclonality.

CONCLUSION

HPV-16 is the most prevalent type among VIN II/III. HPV-16 and HPV-18 DNA integration into host cell genome seems to be related to the progression stage of vulvar dysplasia and, therefore, may be necessary for development of HPV-associated invasive vulvar carcinoma.

High-risk human papillomavirus infection of the genital tract of women with a previous history or current high-grade vulvar intraepithelial neoplasia

Human papillomavirus (HPV) infection is associated with high-grade vulvar intraepithelial neoplasia (VIN-3). The prevalence of anogenital HPV infection in women with previously treated VIN-3 has not been documented yet. This cross-sectional study compared high-risk HPV DNA detection rates in women with past (n = 30) and current (n = 22) VIN-3 to those without current or past VIN (n = 86). HPV DNA was detected in vulvar and cervical samples with Hybrid Capture 2 (HC-2). Smoking was associated in multivariate analysis with current VIN-3 (odds ratio (OR) 8.3, 95% confidence interval (CI) 2.0-8.2) and any VIN-3 history (OR 6.5, 95% CI 2.5-16.5). High-risk HPV DNA was found on the vulva of 64%, 33%, and 20% of women with current VIN-3, past VIN-3, and without previous or current VIN, respectively. After controlling for age and smoking, high-risk HPV vulvar infection was associated with cervical high-risk HPV infection (OR 8.6, 95% CI 2.8-26.5; P = 0.001). After controlling for age, HPV infection was more often multifocal in women with current VIN-3 compared to women with previous but no current VIN-3 lesion (OR 17.6, 95% CI 1.4-227.2). Multifocal vulvar HPV infection was detected in women with previous or active VIN-3. Longitudinal studies are required to determine if the multifocality of HPV infection on the vulva could explain the high recurrence rate of VIN-3.

Evaluation of different treatment modalities for vulvar intraepithelial neoplasia (VIN): CO(2) laser vaporization, photodynamic therapy, excision and vulvectomy

OBJECTIVES

To evaluate various treatment modalities for vulvar intraepithelial neoplasia (VIN) in relation to possible risk factors for recurrence.

METHODS

Retrospective review of 93 patients with VIN treated by CO(2) laser vaporization, photodynamic therapy with aminolevulinic acid (PDT), excision or vulvectomy.

RESULTS

40.4% of the 47 patients with laser vaporization, 48.1% of 27 patients with PDT, 42% of 12 patients with local excision and none of the 7 patients treated by vulvectomy experienced a relapse within a mean follow-up of 53.7 months. The risk for recurrence significantly increased with VIN grade (P = 0.02), multifocal VIN disease (P = 0.01), multicentric intraepithelial neoplasia (P = 0.05) and high-risk HPV infection (P < 0.001). In multivariate analysis, only HPV status remained significant (P = 0.012) and, if HPV testing is not available, multifocality (P = 0.03). The lowest rate of postoperative side effects was noted in patients after PDT. There was one (1%) case of progression to vulvar cancer.

CONCLUSIONS

Vulva preserving treatment methods for VIN have high recurrence rates, especially in patients with HPV infection and multifocal disease. Therefore, careful long-term surveillance is mandatory.

Presence and type of oncogenic human papillomavirus in classic and in differentiated vulvar intraepithelial neoplasia and keratinizing vulvar squamous cell carcinoma

The presence and type of oncogenic papillomavirus (HPV) in classic warty/basaloid vulvar intraepithelial neoplasia and in differentiated vulvar intraepithelial neoplasia and keratinizing vulvar squamous cell carcinoma was investigated using three techniques, that is, histology, in situ hybridization, and PCR-ELISA. HPV typing was performed using in situ hybridization and PCR-ELISA. Differentiated vulvar intraepithelial neoplasia and invasive keratinizing vulvar squamous cell carcinoma proved completely negative for HPV by PCR-ELISA, in situ hybridization, and histologic examination, while in classic vulvar intraepithelial neoplasia, a HPV positivity of 66.1% was found. HPV 16 was the predominant type, with HPV 35, 33, and 52 types found rarely and sometimes together with HPV 16. PCR-ELISA proved to be the most suitable method to detect and type mucosal oncogenic HPVs. The absolute absence of HPV DNA in differentiated vulvar intraepithelial neoplasias and in keratinizing vulvar squamous cell carcinoma suggests a strong HPV-independent pathway of malignant progression to invasive carcinoma.

The simplex (differentiated) variant of vulvar intraepithelial neoplasia

BACKGROUND

The simplex (differentiated) variant of vulvar intraepithelial neoplasia is rarely reported. It is regarded as more likely than "classic" carcinoma in situ to be associated with invasion and can be easily mistaken for benign lesions.

OBJECTIVE

The objective was to present a case of simplex variant of vulvar intraepithelial neoplasia in a 67-year-old woman that was initially misdiagnosed as lichen simplex chronicus.

METHODS

A case report is reported and the literature is reviewed.

RESULTS

Surgical excision with a free margin of 5 mm was performed and no evidence of recurrence was noted during the follow-up period of 6 months.

CONCLUSION

The simplex vulvar intraepithelial neoplasia is an easily overlooked premalignant disease, and it can be cured with surgical treatment if diagnosed correctly and early.

Misdiagnosis of high-grade vulvar intraepithelial neoplasia (VIN III) as mild cervical intraepithelial neoplasia (CIN I) on Papanicolaou tests

CONTEXT

Although high-grade vulvar intraepithelial neoplasia (VIN III) is a clinically significant lesion, it can be overlooked because of nonspecific clinical findings and the fact that its cytomorphologic features mimic those of mild cervical intraepithelial neoplasia (CIN I).

OBJECTIVE

To determine if there are cytomorphologic features on Papanicolaou tests that can reliably distinguish between VIN III and CIN I.

DESIGN

Papanicolaou tests diagnosed as CIN I from patients with biopsy-proven CIN I were compared with Papanicolaou tests diagnosed as CIN I from patients with biopsy-proven VIN III but with no biopsy-proven CIN I.

RESULTS

None of the cytomorphologic features evaluated could reliably distinguish CIN I from VIN III.

CONCLUSION

Since the Papanicolaou test cannot be used to distinguish between CIN I and VIN III, the clinician must pay careful attention to the clinical and colposcopic findings. Further research evaluating the use of ancillary studies, such as human papillomavirus typing, may be useful.

Photodynamic therapy of vulvar and vaginal condyloma and intraepithelial neoplasia using topically applied 5-aminolevulinic acid

BACKGROUND AND OBJECTIVES

To determine the feasibility of photodynamic therapy (PDT) of vulvar and vaginal condyloma and intraepithelial neoplasia (VIN, VAIN) and to compare PDT results with conventional treatments.

STUDY DESIGN/MATERIALS AND METHODS

Thirty-eight patients with vulvar or vaginal intraepithelial neoplasia (VIN) grade II/III (n = 22) or condyloma (n = 16) had 10% 5-aminolevulinic acid (ALA)-gel applied topically. After 2-4 hours, 80-125 J/cm(2) laser light at a wavelength of 635 nm was applied. PDT was compared to conventional treatments for condyloma (CO(2) laser evaporation) and for VIN III (laser evaporation, surgical excision).

RESULTS

The complete clearance rate for condyloma treated by PDT was 66% and the rate for IN was 57% (as determined by biopsy). Of the neoplasia patients, none with hyperkeratotic VIN (n = 4) responded, and only one of four with increased pigmentation cleared. No scarring occurred, and postoperative discomfort lasted 4.9 +/- 3.4 days. Reduced disease-free survival (DFS) was associated with multifocal VIN (P = 0.02, OR 2.17, 95% CI 1.15-4.08), but DFS did not vary with treatment mode.

CONCLUSIONS

Although PDT is not equally efficacious for all subgroups, PDT for condyloma and intraepithelial neoplasia appears to be as effective as conventional treatments, but with shorter healing time and excellent cosmetic results.

Laminin-5 gamma 2 chain as an invasivity marker for uni- and multifocal lesions in the lower anogenital tract

During recent decades it has become apparent that there are two types of vulvar disease: the classic type found in elderly women with unicentric and unifocal lesions, and the type found in younger women, in which precancerous and invasive changes develop in the anogenital lower tract in a multicentric and multifocal fashion, often over a long period of observation. The laminin-5 gamma 2 chain is an extracellular protein that is a component of the basement membrane. Recently its expression has been recognized as a marker in cervical cancer that permits identification of invasive capacity. The aim of our study was to determine if laminin-5 gamma 2 chain antibody can act as a sensitivity marker of invasive capacity in precancerous and invasive carcinoma in women with uni- and multifocal changes in the anogenital tract. The result showed that all patients in the older group of women with invasive carcinoma of the vulva had moderate to high positive expression of the laminin-5 gamma 2 chain. In the group of younger patients with multifocal precancerous changes observed over long periods, most of the patients with vulva intraepithelial neoplasia (VIN) 3 showed laminin-5 gamma 2 chain positivity already in the precancerous changes, and all of them developed invasivity during the period of observation. Normal epithelium without atypia was mostly negative or of low immunoreactivity of laminin-5. In conclusion, positive laminin-5 gamma 2 chain expression seems to indicate the invasiveness potential of precancerous lesions and is also expressed in all investigated invasive carcinomas of the anogenital tract.

Diagnosis and management of vulvar and vaginal intraepithelial neoplasia

Vulvar intraepithelial neoplasia and VAIN present unique challenges to the practicing gynecologist. VIN may produce distressing symptoms and undergo malignant conversion. A high index of suspicion and liberal use of biopsy are required to make the diagnosis. The approach to therapy for VIN has been reviewed. Treatment should be tailored to each individual patient and may include a period of expectant observation. Variations and combinations are used whenever necessary to preserve normal function and anatomy. Frequent surveillance is a must because recurrence rates are high, especially with multifocal disease in young women. Although VAIN accounts for less than 0.5% of lower genital tract neoplasia, the frequency of its detection is increasing, especially in younger patients. These lesions are most commonly found in the upper third of the vagina and are often multifocal in nature. The close proximity of the upper vagina to the rectum, bladder, and ureters makes treatment difficult. The occult invasion rate may be as high as 28%, and a wide variety of therapies are available. As is true for VIN, recurrence is not uncommon.

Highly differentiated keratinizing squamous cell cancer of the cervix: a rare, locally aggressive tumor not associated with human papillomavirus or squamous intraepithelial lesions

The purpose of this study is to report an unusual variant of cervical squamous cell carcinoma, not associated with either human papillomavirus infection or antecedent squamous intraepithelial lesions. Five women had a diagnosis of invasive cervical cancer discovered at hysterectomy performed for prolapse (two cases), leiomyoma (one case), or a vaginal fistula (two cases). The women ranged in age from 47 to 78 years (mean 59 years). Four of the five had a history of normal Papanicolaou (Pap) smears; the other had a Pap smear diagnosis of atypical squamous cells of undetermined significance (ASCUS). All had large cervical tumors (two with parametrial involvement and one with vaginal involvement) that showed extensive keratin formation, an inverted pattern of growth, and, except for one case, minimal cytologic atypia. There was extensive hyperkeratosis and parakeratosis adjacent to each tumor; none had evidence of squamous intraepithelial lesion. Human papillomavirus testing by polymerase chain reaction in situ hybridization and reverse-transcribed polymerase chain reaction in situ was negative in each case, compared with a detection rate of 107 of 108 (99%) for squamous intraepithelial lesion-associated cervical squamous cell and adenocarcinomas. Two of the women died of extensive local recurrence; two other women were recently diagnosed. We conclude that highly differentiated keratinizing squamous cell carcinoma of the cervix is a rare entity not associated with human papillomavirus infection or squamous intraepithelial lesion and thus difficult to detect on routine cervical cancer screening.

Loss in 3p and 4p and gain of 3q are concomitant aberrations in squamous cell carcinoma of the vulva

Neoplasm of the vulva is a rare malignancy accounting for <5% of all female genital-tract cancer. However, in recent years the incidence of vulva intraepithelial neoplasia, known to serve as a precursor to carcinoma, has increased in young women generating considerable interest in its pathogenesis. Genetic changes at the molecular level in precursor or invasive vulvar tumors are not well investigated, and DNA copy number changes have not been reported until now. We used comparative genomic hybridization (CGH) to analyze genetic alterations in 10 primary invasive squamous cell carcinomas of the vulva. Chromosomal aberrations were identified in 8/10 cases. The most frequent chromosomal losses were 4p13-pter (five cases), 3p (four cases), and 5q (two cases), and less frequent losses were detected at 6q, 11q, and 13q (one case each). The most frequent chromosomal gains were 3q (four cases) and 8p (three cases), and less frequent gains were found in 9p, 14, 17, and 20q (one case each). The pattern of chromosomal imbalance in vulvar cancer detected by CGH was revealed to be very similar to that in cervical cancers, despite regional differences in their prevalence. These results suggest that the pathogenic pathways in vulvar and cervical carcinomas may be similar and that the genetic background may be common to these two squamous cell carcinomas.

Prognostic Significance of Epithelial Disorders Adjacent to Invasive Vulvar Carcinomas

OBJECTIVE

Epithelial disorders are found adjacent to vulvar carcinoma in 70-80% of patients. Epithelial disorder may be human papillomavirus related [undifferentiated high-grade vulvar intraepithelial neoplasia (VIN III)] or not [vulvar lichen sclerosus and squamous cell hyperplasia with or without atypia (differentiated VIN III)]. The aim of this study was to evaluate the impact of associated epithelial disorders on the outcome of patients with cancer of the vulva.

METHODS

A retrospective study about 108 patients treated for a squamous cell carcinoma of the vulva was performed. Clinical, surgical, histopathologic, and follow-up data were collected and analyzed.

RESULTS

Seventy-seven patients had an epithelial alteration adjacent to the invasive squamous carcinoma. Squamous cell hyperplasia and lichen sclerosus were identified in 48% (n = 52) and undifferentiated VIN III in 23% (n = 25). The 5-year disease-free and overall survival rates were 39 and 55%, respectively. In univariate analysis, age <70, a tumor size <2 cm, depth of invasion < or =1 mm, tumor thickness < or =5 mm, negative lymph node pathology, lymph node resection, and undifferentiated VIN III were predictive of survival. Using Cox's proportional hazards method, undifferentiated VIN III (P = 0.02), depth of invasion < or =1 mm (P < 0.01), and a pathological negative node status (P < 0.01) were independent predictors of survival. Patients without associated epithelial alterations had clinical and prognostic features comparable to those of patients with vulvar lichen sclerosus and squamous cell hyperplasia.

CONCLUSION

The results of this study support the view that histological evidence of epithelial alterations adjacent to invasive carcinoma can serve to separate patients that differ in terms of prognosis.

Vulvar intraepithelial neoplasia: historical aspects and current status

Vulvar intraepithelial neoplasia (VIN) is the currently accepted generic designation for the spectrum of vulvar lesions with the histologic features of squamous dysplasia and squamous cell carcinoma in situ. Although several classifications of VIN have been espoused in the past 20 years, VIN can be readily classified into two principal clinicopathologic types: classic (bowenoid) VIN and simplex (differentiated) VIN. This manuscript summarizes the historical development and current status of our knowledge about VIN. Information on the clinical and pathologic aspects are detailed and illustrated, as are considerations of differential diagnosis.

The role of human papillomavirus in gynecological diseases

Papanicolaou (Pap) smears of the cervix and biopsies of the cervix, vagina, vulva, and penis are a substantial portion of the work load of any anatomic pathology laboratory. The importance of samples from these sites is highlighted by the fact that their most common disease is dysplasia, which is sexually transmitted and a recognized risk factor for carcinoma. Human papillomavirus (HPV) is an essential co-factor for the development of lower genital tract dysplasia. Molecular testing for HPV has revealed a great deal about the pathophysiology of dysplasia and its evolution to carcinoma. Importantly, it now allows diagnostic pathologists the opportunity to be more accurate in their assessment of common conditions such as Pap smears of squamous atypia and biopsies equivocal for dysplasia. This review highlights the role of HPV in the evolution of disease in the lower genital tract and stresses the utility of HPV testing to the diagnostic pathologist.

Contemporary experience with the management of vulvar intraepithelial neoplasia

Experience with 40 cases of vulvar intraepithelial neoplasia seen during the 7-year period 1992-98 is detailed. The average age was 46.2 years and 27 of the patients (67.5%) were aged 50 years or younger. There was a significant association with cigarette smoking when compared with age-matched control patients attending the Vulvar Clinic with non-neoplastic conditions (67.5 vs. 12.5%; P = 0.001). Twenty-five percent of the patients had a past history of cervical intraepithelial neoplasia (CIN). The disease was multifocal in 77.5% of patients-92.6% of women aged less than 50 years and 53.8% of older women (P = 0.014). Treatment was by surgical excision supplemented in some cases by laser ablation. Occult stromal invasion was detected histologically in 15% of cases and in half of these, the invasion was to a depth considered to have significant metastatic potential. Recurrence occurred in 50% of patients and was more common in patients with multifocal disease. One patient (2.5%), aged 30, developed invasive vulvar carcinoma 4 years after treatment.

Vulvar intraepithelial neoplasia of the simplex (differentiated) type: a clinicopathologic study including analysis of HPV and p53 expression

The simplex (differentiated) variant of vulvar intraepithelial neoplasia (VIN) has not been well characterized. The authors studied the clinicopathologic features of 12 cases of simplex VIN and obtained follow-up data to assess its relationship to vulvar invasive squamous cell carcinoma (InvSCC). Expression of p53 protein was analyzed immunohistochemically and compared with adjacent non-neoplastic epidermal lesions. Assessment of human papilloma virus (HPV) deoxyribonucleic acid was done by polymerase chain reaction amplification and in situ hybridization. All patients were of postmenopausal age (mean age, 66.8 years). Three patients had a history of prior vulvar InvSCC and one had a separate synchronous vulvar InvSCC. Squamous hyperplasia was present in the adjacent epidermis in 10 patients and lichen sclerosus (LS) was present in four patients. Histologically, simplex VIN differed from "classic" VIN by its highly differentiated features. The characteristic features included parakeratosis, thickened epidermis with elongated and anastomosing rete ridges, enlarged abnormal keratinocytes with premature eosinophilic cytoplasmic differentiation extending deeply within the epidermis, whorling of enlarged keratinocytes or keratin pearl formation within rete ridges, prominent intercellular bridges, and dysplastic basilar cells. One patient had minimal microinvasion (0.6 mm). Ten of 12 patients had positive p53 immunostaining staining with suprabasilar extension of p53 positive cells in each patient. The labeling index (LI) of basilar cells ranged from 0% to 99% (median, 94.5%). Non-neoplastic lesions in the adjacent epidermis had p53-positive basal cells in nine of 11 evaluable cases. The LI was significantly lower in these lesions, with a median of 4% in squamous hyperplasia and 7.5% in LS; none had suprabasilar extension of p53-positive cells. HPV (type 31/35/51) was identified in only one simplex VIN--a p53-negative lesion. Staining for p53 often delineated sharply the junction between simplex VIN and squamous hyperplasia. Four patients subsequently developed vulvar InvSCC at 5, 6, 9, and 55 months. All four InvSCCs were of the conventional keratinizing type and were HPV negative, as were the one synchronous and two prior InvSCCs. The authors conclude that (1) simplex VIN has a strong association with vulvar InvSCC and is a probable precursor lesion of HPV-negative vulvar InvSCCs, (2) HPV is very uncommon in simplex VIN and probably does not play an important role in its genesis, (3) alteration of the p53 gene appears to be involved in the development of simplex VIN, and (4) immunostaining for p53 protein may be helpful in the differential diagnosis of simplex VIN.

Squamous cell carcinoma of the vulva in Brazil: prognostic importance of host and viral variables

BACKGROUND

Certain clinicopathologic features of vulvar squamous cell carcinoma have been correlated with adverse prognosis. However, few large-scale studies have addressed their role in patient survival. This study examined the relationship between multiple variables and prognosis in a large group of vulvar cancers in Brazil.

METHODS

One hundred eighty-four Brazilian women with vulvar carcinoma were studied and the following variables recorded: age, pathologic TNM stage, survival, histologic grade, tumor histologic pattern, invasion pattern, tumor thickness, and tissue stromal and inflammatory response. Human papillomavirus (HPV) was detected by polymerase chain reaction amplification of extracted archival DNA. Data were analyzed using Cox proportional hazards modeling.

RESULTS

After controlling for age, the probability of cancer survival decreased with increasing age, stage, grade, and tumor thickness, a fibromyxoid stromal response, infiltrative growth pattern, and basaloid histologic pattern. With the exception of fibromyxoid stromal response, each of these variables remained prognostically significant after adjustment for several other predictors in a multivariate model. Women whose tumors displayed a basaloid pattern were 3.5 times as likely to die from cancer than those with keratinizing tumors [hazard ratio (HR) = 3.5, 95% CI(1.3-9.2)]. An infiltrative invasion pattern strongly increased the probability of cancer death [HR = 4.6, 95% CI(1.9,11.4)]. HPV status did not influence survival, despite its association with basaloid histology.

CONCLUSIONS

Previously reported associations of negative HPV status and fibromyxoid response with adverse prognosis in vulvar cancer were not confirmed by multivariate analysis. Basaloid variants, and particularly diffusely infiltrative tumors, carry an adverse prognosis.

Human papillomavirus types 16 and 39 in a vulval carcinoma occurring in a woman with Hailey-Hailey disease

A woman with Hailey-Hailey disease, suffering from carcinoma of the vulva, was examined by histology and for the presence of human papillomavirus (HPV) DNA by polymerase chain reaction (PCR) and in situ hybridization. Our diagnosis by histological examination revealed the vulval carcinoma to be a squamous cell carcinoma (SCC), adjacent to lesions of Hailey-Hailey disease and severe dysplasia/carcinoma in situ [vulval intraepithelial neoplasia (VIN) III]. The PCR with consensus primers for the L1 region (L1-PCR) successfully amplified HPV DNA using total DNA extracted from formalin-fixed and paraffin-embedded tissue specimens. Restriction fragment length polymorphism analysis and sequencing of L1-PCR products revealed HPV types 16 and 39. HPV 16-specific primers for the E6 region identified HPV 16 DNA. In situ hybridization analysis with biotinylated HPV 16 and 39 DNA probes revealed the presence of the HPV 39 genome in the nuclei of the tumour cells in the SCC. These results indicate that HPV 16 and 39 are associated with lesions in vulval carcinoma. Regarding the patient's susceptibility to infection in the case of Hailey-Hailey disease, there is a possibility that HPV was inoculated into the lesions of Hailey-Hailey disease and induced those of VIN III and SCC.

Selected epidemiological time trends of vulvar carcinoma in Israel

Recently, considerable demographic changes have occurred in Israel. The purpose of the present population-based nationwide epidemiological study of carcinoma of the vulva was to assess changes over time in incidence, relative frequency, age pattern and ethnic distribution. The study group included all 257 Jewish females with histologically confirmed neoplasms of the vulva diagnosed in Israel during the ten year period from 1985 to 1994. Data were obtained from the Israeli Cancer Registry and compared with data from a previous study covering a 13 year period (1961 to 1973). The relative frequency of carcinoma in situ (CIS) of the vulva increased significantly during the later period (from 5.4% to 12.8%), while that of invasive vulvar carcinoma declined significantly (from 80.6% to 69.6%). Regarding invasive vulvar carcinoma, a significant decrease in the age-adjusted standardized rates and in the mean annual incidence rate in the 70+ age group was found. The ethnic distribution pattern of invasive vulvar carcinoma did not change and remained similar to that of cervical carcinoma, namely a trend for higher incidence among women born in North Africa. The increased frequency of vulvar CIS is attributed mainly to a greater propensity to perform vulvar biopsies. The possibility of a consequent decline of vulvar carcinoma cannot be ruled out.

Basaloid squamous cell carcinoma: a distinctive human papilloma virus-related penile neoplasm: a report of 20 cases

Most penile neoplasms are squamous cell carcinomas (SCC), but there are subtypes that show morphologic and possibly etiologic differences. Clinicopathologic features of 20 patients with basaloid carcinoma (BC), an unusual variant of squamous cell carcinoma, are presented. Median age was 52 years, and all tumors were located in the glans, three confined to the perimeatal region. Average tumor size was 3.8 cm. Microscopically, nests of small, basophilic cells with numerous mitosis were present. Human papillomavirus DNA sequences (type 16), using the polymerase chain reaction (PCR), were found in 9 of 11 cases. Differential diagnosis included urethral transitional cell, basal cell, small cell neuroendocrine, and metastatic carcinoma. Factors more significantly associated with regional metastasis and mortality were tumor thickness greater than 10 mm and infiltration of the corpus cavernosum. A comparison with typical squamous cell carcinoma showed basaloid carcinoma to have a higher histologic grade, a deeper invasion of penile anatomic levels, and a higher mortality rate. Of 17 patients observed, 10 were dead of disease (average time, 34 months), one was alive with disease 6 months after diagnosis, and 5 were alive and free of disease (average time, 71 months); the remaining patient died of other causes. Basaloid carcinoma is a distinctive morphologic subtype of squamous cell carcinoma frequently associated with the human papilloma virus.

Bowenoid papulosis showing polyclonal nature

Bowenoid papulosis (BP) is characterized clinically by its benign-looking appearance and histologically by the features of high grade squamous intraepithelial lesions (SILs). The external genitalia of young people is a common site of occurrence, and most of the lesions undergo resolution by local treatments or even spontaneously. A strong association between BP and high risk types of human papillomavirus (HPV), especially HPV 16, has been reported and the incorporation of BP into the SIL category is generally accepted, but controversy still exists as to the true nature of BP. We analyzed the clonality of BP lesions occurring on both sides of the vulva of a 15-year-old girl. DNA was subjected to a polymerase chain reaction-based clonal analysis using the highly informative androgen receptor gene (HUMARA) with a nonisotopic modification. The clonal analysis of each BP lesion showed a random X-chromosome inactivation pattern, indicating a polyclonal nature of this disorder. Although monoclonal proliferation of vulvar SIL was recently reported, this is the first report of the polyclonality in a type of SIL diagnosed as BP, supporting a clinicopathologic heterogeneity in SIL of the vulva.

Human papillomavirus infection in squamous cell carcinoma of the vulva, in various synchronous epithelial changes and in normal vulvar skin

OBJECTIVE

To investigate the prevalence of human papillomavirus (HPV) infection in various vulvar lesions.

METHODS

HPV infection using consensus primer-PCR was studied in 66 patients with vulvar carcinoma and in the synchronous epithelial lesions.

RESULTS

HPV infection was present in 13/66 carcinoma, in 1/33 VIN I, in 3/11 VIN II, in 8/16 VIN III, in 2/30 lichen sclerosus, in 1/37 squamous cell hyperplasia, and in 2/55 normal skin specimens. Normal skin from healthy controls showed HPV-negative specimens only. Patients with HPV-positive carcinomas were younger, presented in lower stages, and had high-grade VIN more often than those with HPV-negative carcinomas.

CONCLUSIONS

In sum we found that all types of epithelial changes synchronous with carcinoma of the vulva showed HPV infection, indicating that they all might have malignant potential.

Presence of human papillomavirus DNA and expression of L-fucose moiety in some vulvar intraepithelial lesions and vulvar squamous cell carcinoma

BACKGROUND

Human papillomavirus could reside and play an etiological role in some vulvar epithelial lesions. Human papillomavirus-infected keratinocytes might have certain biochemical changes that could be of significance in helping clinical diagnosis or elucidating the pathogenesis of some vulvar epithelial diseases.

OBJECTIVE

To detect the presence of human papillomavirus DNA and observe the expression pattern of L-fucose moiety in some vulvar intraepithelial lesions and vulvar squamous cell carcinoma.

METHODS

Nineteen cases of vulvar intraepithelial lesions and 13 cases of vulvar squamous cell carcinoma from the inner aspect of labia majora or the outer aspect of labia minora were selected. Polymerase chain reaction was employed to detect the presence of human papillomavirus DNA in lesional skin. Ulex europeaus agglutinin-1 histochemistry was used to observe the L-fucose expression pattern.

RESULTS

A large proportion of vulvar intraepithelial lesions had the presence of human papillomavirus DNA, but the positive rate was low in vulvar squamous cell carcinoma and squamous cell hyperplasia. L-Fucose expression was much more pronounced in human papillomavirus DNA-positive lesions than those negative ones.

CONCLUSIONS

Human papillomavirus had an important impact on some vulvar intraepithelial lesions in this Oriental population. The expression pattern of L-fucose may be used as an indicator for vulvar keratinocyte transformation by human papillomavirus.

Cofactors with human papillomavirus in a population-based study of vulvar cancer

BACKGROUND

Human papillomavirus (HPV) has been previously associated with vulvar cancer. In a population-based study, we examined whether exposure to HPV, cigarette smoking, or herpes simplex virus 2 (HSV2) increases the risk of this cancer.

METHODS

Incident cases of in situ (n = 400) and invasive (n = 110) squamous cell vulvar cancer diagnosed among women living in the Seattle area from 1980 through 1994 were identified. Serum samples were analyzed for antibodies against specific HPV types and HSV2. HPV DNA in tumor tissue was detected by means of the polymerase chain reaction. In most analyses, case subjects were compared with population-based control subjects (n = 1403). Relative risks of developing vulvar cancer were estimated by use of adjusted odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Increased risks of in situ or invasive vulvar cancer were associated with HPV16 seropositivity (ORs = 3.6 [95% CI = 2.6-4.8] and 2.8 [95% CI = 1.7-4.7], respectively), current cigarette smoking (ORs = 6.4 [95% CI = 4.4-9.3] and 3.0 [95% CI = 1.7-5.3], respectively), and HSV2 seropositivity (ORs = 1.9 [95% CI = 1.4-2.6] and 1.5 [95% CI = 0.9-2.6], respectively). When the analysis was restricted to HPV16 DNA-positive tumors (in situ or invasive), the OR associated with HPV16 seropositivity was 4.5 (95% CI = 3.0-6.8). The OR for vulvar cancer was 18.8 (95% CI = 11.9-29.8) among current smokers who were HPV16 seropositive in comparison with never smokers who were HPV16 seronegative.

CONCLUSIONS

Current smoking, infection with HPV16, and infection with HSV2 are risk factors for vulvar cancer. Risk appears particularly strong among women who are both current smokers and HPV16 seropositive.

Age-dependence of human papillomavirus DNA presence in oral squamous cell carcinomas

The aetiology of oral cancer is thought to be multifactorial. Apart from the two known major risk factors (tobacco and alcohol), a viral aetiology has been proposed, with special reference to human papillomavirus (HPV). 35 cases of oral squamous cell carcinoma (OSCC), seen at the Departments of Oral & Maxillofacial Surgery and Oral Pathology and Otolaryngology of the Free University of Amsterdam, were analysed as well as 12 biopsies of clinically and histologically normal gingival mucosa collected from healthy individuals after tooth extractions, using the polymerase chain reaction (PCR) and two different sets of primers that are able to detect a broad spectrum of HPV types. An overall HPV positivity of 54.3% in OSCC was found, the majority of positive cases (78.9%) harbouring HPV type 16. In contrast, no positivity for HPV was detected in the clinically normal oral mucosal samples analysed. Furthermore, a significant association between HPV presence and age was found: patients older than 60 years showed a lower prevalence of the virus (29.4%) compared with patients below this age (77.8%) (P < 0.05). The results from the present study suggest an association between HPV and OSCC, particularly in patients under the seventh decade.

Mutation of tumor suppressor gene p53 is frequently found in vulvar carcinoma cells

OBJECTIVE

The purpose of this study was to evaluate the presence and type of mutations of the tumor suppressor gene p53 in squamous carcinoma cell lines of the vulva.

STUDY DESIGN

Eight low-passage cell lines established from vulvar carcinoma were included in the analysis. Mutational analysis was restricted to exons 5 through 9 of the p53 gene, previously shown to have a high incidence of mutations. The sequences containing exons 5/6,7, and 8/9 were amplified by polymerase chain reaction and screened with a single-strand conformation polymorphism technique on PhastSystem (Pharmacia Biotech, Uppsala, Sweden). Exons from samples showing mobility shifts in single-strand conformation polymorphism were sequenced by polymerase chain reaction direct sequencing.

RESULTS

Five vulvar carcinoma cell lines showed abnormal electrophoretic mobility of exons 5/6, one of exons 8/9, and one of exon 7. Reduction to homozygosity was detected in four vulvar carcinoma cell lines. Missense mutations were detected by sequence analysis in UM-SCV-2 (codon 171: GAG[Glu]-->TAG[STOP]), UM-SCV-3 (hot spot codon 273: CGT[Arg]-->TGT[Cys]), UM-SCV-4 (codon 151: CCC[Pro]-->CAC[His]), UM-SCV-5 (codon 155: ACC[Thr]-->ATC[lle]), and UM-SCV-7 (codon 245: GGC[Gly]-->AGC[Ser]). UM-SCV-3 also carried a missense mutation with no amino acid change (codon 314: TCC[Ser]-->TCT[Ser]). UM-SCV-7 carried an additional base deletion at codon 249 (AGG-->AG-), likely resulting in a frameshift in transcription and a truncated protein product. Four of the seven mutations were transitions, two were transversions, and one was a deletion. The presence of transitions suggests that at least a proportion of p53 mutations of these cancers may arise spontaneously without exogenous carcinogen exposure. UM-SCV-1A and UM-SCV-1B were derived from the primary tumor and pleural effusion of the same patient. UM-SCV-6 is a cell line that contains human papillomavirus 16. No mutations in these three cell lines were found by single-strand conformation polymorphism.

CONCLUSIONS

On the basis of previous observations, loss of tumor suppressor p53 function either by mutation or human papillomavirus involvement is a frequent phenomenon in cervical carcinoma cells. It appears now that functional inactivation of p53 is associated also with vulvar carcinoma cell lines, but mutations of the p53 gene are much more common in vulvar than in cervical carcinoma cell lines.

Human papillomavirus (HPV) in vulvar dysplasia and carcinoma in situ

Surgical specimens from 62 patients with vulvar dysplasia and carcinoma in situ were morphologically investigated. Lesions were classified according to WHO (mild, moderate, severe dysplasia and carcinoma in situ) and according to Toki et al. (1991) (warty, basaloid, combined warty/basaloid or basaloid/warty types or mixed (warty, basaloid and simple) forms). Following the WHO classification, moderate dysplasia was shown in 4 cases, severe dysplasia in 47 and carcinoma in situ in 11 cases. Pure warty type was shown in 2 cases (both biopsy specimens). One case revealed pure simple dysplasia whereas no case of pure basaloid type was found. Various combinations of warty and basaloid types were shown in 52 cases and mixed forms in 7 cases. The results indicate that pure forms of warty and basaloid types probably do not exist. HPV DNA was detected by PCR in 51/58 cases (88%) (45 with HPV type 16 and 6 with HPV type 33) evenly distributed in all age groups and in all types of lesions (WHO and Toki et al. 1991). By ISH HPV was detected in 24/62 cases (39%) (21 with HPV type 16/18 and 3 with HPV type 31/33), nearly always in warty areas. All these cases were positive for the same virus type by PCR. No case revealed more than one type of HPV. HPV type 6, 11, 18, and 31 were not detected by PCR. The results indicate a correlation between HPV type 16 and 33 and dysplasia/carcinoma in situ in the vulva.