Premalignant and malignant squamous lesions of the vulva

Vulvar premalignant squamous lesions include low- and high-grade intraepithelial neoplasias. High-grade lesions include classic (usual) and differentiated (simplex) vulvar intraepithelial neoplasia (VIN). Classic VIN (cVIN), the most common, is related to human papilloma virus (HPV), occurs in younger patients, and is frequently multifocal. Differentiated VIN (dVIN), less common, is related to lichen sclerosus and other chronic vulvar dermatoses, occurs in older women, and is usually unifocal. Terminology schemes for premalignant lesions are reviewed. Invasive squamous cell carcinoma also occurs in two distinct clinicopathologic settings. Most conventional keratinizing squamous cell carcinomas arise from a background of dVIN and comprise the majority of invasive squamous tumours. Warty and basaloid invasive squamous cell carcinomas likely develop from cVIN and comprise a minority of invasive tumours. Clinical features, microscopic findings, differential diagnoses, immunoprofile, prognosis and treatment of premalignant and malignant lesions are addressed.     

Specific intraepithelial localization of mast cells in differentiated vulvar intraepithelial neoplasia and its possible contribution to vulvar squamous cell carcinoma development

van de Nieuwenhof H P, Hebeda K M, Bulten J, Otte‐Holler I, Massuger L F A G, de Hullu J A & van Kempen L C L T
(2010) Histopathology 57, 351–362
Specific intraepithelial localization of mast cells in differentiated vulvar intraepithelial neoplasia and its possible contribution to vulvar squamous cell carcinoma development Aims: The aetiology of vulvar squamous cell carcinomas (SCC) that are not causally associated with high‐risk human papillomavirus remains largely elusive. The aim of this study was to analyse the inflammatory response in its presumed precursor lesions, lichen sclerosus (LS) and differentiated vulvar intraepithelial neoplasia (dVIN), and provide evidence that dVIN is a likely precursor of vulvar SCC. Methods and results: Immunohistochemical analyses for CD4+, CD8+, CD20+, CD68+, S100+ and tryptase‐positive immune cells were performed and quantified in LS (n = 7), dVIN (n = 19), SCC (n = 11), and normal vulvar tissue (n = 8). The subepithelial inflammatory response in dVIN and SCC was comparable, but absent in LS. Abundant intraepithelial mast cells were observed in dVIN only, and confirmed by electron microscopy, toluidine blue staining and cKIT expression. Adjacent keratinocytes displayed increased proliferation as determined by MIB‐1 positivity. Electron microscopy revealed intraepithelial mast cell degranulation. Intraepithelial mast cells were not or infrequently observed in vulvar hyperplasia (n = 13), condylomata acuminata (n = 5), keratinocytic intraepidermal neoplasia of sun‐exposed skin (n = 15), epidermal hyperplasia of head and neck (n = 12), and psoriasis (n = 3). Conclusions: These data indicate that dVIN can be recognized by intraepithelial mast cells and that they might promote the progression of dVIN to SCC.     

Small vulvar squamous cell carcinomas and adjacent tissues. A morphologic study

Vulvar squamous cell carcinomas are of different subtypes and degrees of differentiation, and may be associated with adjacent lichen sclerosus and/or varying degrees of dysplasia. The aim of this investigation was to study small carcinomas with a diameter of less than 2 cm in order to find a possible relation between subtypes of carcinomas and adjacent epithelial changes. Fourteen cases of small vulvar squamous cell carcinomas were totally embedded in paraffin. Serial sectioning made a detailed mapping of all different lesions possible, and a two- and three-dimensional imaging was obtained in each case. Seven patients with keratinizing squamous cell carcinomas (median age 65) had adjacent lichen sclerosus. All carcinomas were completely surrounded by areas of VIN1. VIN2 and VIN3 were not found. Seven patients without lichen sclerosus (median age 58) showed squamous cell carcinomas of the keratinizing type (n=2) or the basaloid type (n=5). Five of these cases were incompletely surrounded by varying degrees of dysplasia, mainly VIN2 and VIN3. Two different pathogenetic pathways for the development of vulvar squamous cell carcinoma are likely.     

Premalignant and malignant lesions of the vagina

This paper will review vaginal lesions including common premalignant conditions as well as primary malignant epithelial and mesenchymal neoplasms. Discussion of the precursor vaginal squamous intraepithelial lesion (VaSIL) will precede a section focused on vaginal squamous cell carcinoma (VaSCC). The topics of adenosis and atypical endometriosis will precede discussion of vaginal clear cell carcinoma and endometrioid carcinoma. Vaginal sarcomas and adenosarcomas will be briefly addressed. Metastatic tumours which comprise the majority of vaginal malignancies will also be discussed. The review will conclude with a brief discussion of the neovagina and the rare occurrence of malignancy in this site.     

Premalignant and malignant lesions of the vagina

This paper will review vaginal lesions including the common premalignant and benign lesions as well as the rather rare primary malignant squamous and glandular neoplasms. Risk factors such as human papilloma virus, smoking and diethylstilbestrol exposure as they pertain to the development of premalignant and malignant lesions of the vagina will also be included. Metastatic tumours to the vagina, which comprise the majority of vaginal malignancies, will also be discussed.     

Langerhans cells in vulvar lichen sclerosus and vulvar squamous cell carcinoma

Introduction: Langerhans cells (LCs), specializing in antigen presentation, are a very important part of the skin immune system (SIS). Materials and Methods: Skin biopsies from 22 women with vulvar lichen sclerosus (LS): 15 patients with early and 7 with the late stage of the disease, were evaluated. Five women with vulvar squamous cell carcinoma (SCC) were also examined. The control group consisted of 9 women who underwent plastic surgery of the vulvar region. Immunohistochemical staining was performed on formalin-fixed paraffin-embedded tissues samples using antihuman CD1a antibody (NCL-CD1a-235, Novocastra). Results: Increased numbers of LC stainings were present in early LS, whereas decreased numbers of these cells were present in late LS and in SCC compared with the control group. Conclusions: This study showed that dysregulation of the SIS may lead to suppression of LCs in the vulvar epithelium and may be one of the reasons for a higher tendency for carcinogenesis in the vulvar region.     

Differentiated precursor lesions and low-grade variants of squamous cell carcinomas are frequent findings in foreskins of patients from a region of high penile cancer incidence

Oertell J, Caballero C, Iglesias M, Chaux A, Amat L, Ayala E, Rodríguez I, Velázquez E F, Barreto J E, Ayala G & Cubilla A L
(2011) Histopathology  58 , 925–933
Differentiated precursor lesions and low‐grade variants of squamous cell carcinomas are frequent findings in foreskins of patients from a region of high penile cancer incidence Aims: About 10–20% of all penile squamous cell carcinomas (SCCs) originate in the foreskin, but knowledge about preputial precursor and associated lesions is scant. The aims of the present study were to determine the prevalence of various precancerous and cancerous lesions exclusively affecting the foreskin, and to describe their pathological features. Methods and results: One hundred consecutive circumcision specimens from symptomatic patients living in a region of high penile cancer incidence were analysed. Clinical diagnoses included mostly phimosis and chronic balanoposthitis (40 and 35 cases, respectively), but also a tumour mass (11 cases). Histopathological lesions found included: squamous hyperplasia in 61 cases; lichen sclerosus in 53 cases; penile intraepithelial neoplasia (PeIN) in 30 cases (all differentiated PeIN, with two cases showing multicentric foci of basaloid and warty–basaloid PeIN); and invasive SCC in 11 cases (three usual, three pseudohyperplastic, two verrucous–pseudohyperplastic, and one case each of basaloid, papillary and mixed usual–basaloid carcinomas). Lichen sclerosus was present in all low‐grade SCC cases. Patients with no lesions were younger (mean age 44 years) than those with precursor lesions (mean age 54 years) or with invasive SCC (mean age 68 years). Immunohistochemistry for p16^INK4a was performed in 19 precancerous lesions. All differentiated PeINs (18 lesions) were negative, and one basaloid PeIN was positive. Conclusions: The frequent coexistence of lichen sclerosus, squamous hyperplasia, differentiated PeIN and low‐grade SCC suggests a common non‐human papillomavirus related pathogenic pathway for preputial lesions, and highlights the importance of circumcision in symptomatic patients for the prevention of penile cancer.     

Recent advances in the pathology of the vulva

This review addresses recent and important advances in our knowledge of several uncommon or rare disorders of the vulva including Paget's disease, vulva intraepithelial neoplasia, lichen sclerosus and squamous hyperplasia and their relationship to squamous carcinoma. Emphasis is placed on the two biologically different types of squamous carcinoma related and unrelated to human papillomavirus infection. Finally, the relatively recent concept of the sentinel node as applied to vulva carcinoma is discussed.     

Histopathological work-up and interpretation of sentinel lymph nodes removed for vulvar squamous cell carcinoma

Aims:  To evaluate the work-up of sentinel lymph nodes (SLNs) removed for vulvar pT1–pT2 squamous cell carcinoma (SCC). Inguinal lymphadenectomy yields metastases in only 30% of cases. Patients with missed inguinal disease, however, have a risk of dying from systemic disease. SLN dissections reduce morbidity, but work-up should reliably identify metastatic disease.
Methods and results:  All SLNs removed from 38 patients with pT1–pT2 SCC and clinically negative inguinal lymph nodes were submitted for frozen section analysis. When negative, SLN were formalin-fixed, sectioned entirely at 330-μm intervals to produce three slides per millimetre [two haematoxylin and eosin (H&E) stained slides; one slide for immunohistochemistry]. If screening of H&E-stained sections was negative, all remaining slides were subjected to immunohistochemistry with an antibody to cytokeratin. Twenty-five of 38 patients (66%) were pN0, 7/38 (18%) had metastases on frozen sections/H&E stains. Immunohistochemistry detected micrometastases in two patients and single tumour cells and anucleate cell structures in four patients. In 12/13 patients the SLN metastases, including all single-cell deposits, were from lichen sclerosus (LS)-associated SCC. Twelve of 13 patients with metastases had a pT2 SCC.
Conclusions:  Micrometastases and single tumour cell deposits in SLNs are typical of LS-associated vulvar SCC. Single tumour cell deposits in SNLs should be regarded as 'positive'. Identification requires serial sectioning and immunohistochemical analysis of all removed SLNs.     

Vulval squamous cell carcinoma and its precursors

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

The predictive value of human papilloma virus (HPV) typing in the prognosis of bronchial squamous cell papillomas

Five solitary squamous papillomas of bronchus with variable degrees of dysplasia, one combined with a laryngeal papilloma and with a neuroendocrine carcinoma in the contralateral lung, and five papillomas combined with invasive squamous cell carcinomas were investigated for their expression of human papilloma virus DNA by in situ hybridization. Benign squamous cell papillomas showed an association with papilloma virus type 11 and rarely type 6, whereas types 16 or 18, sometimes in combination with types 31/33/35 were found in papillomas associated with carcinomas. In one patient a benign papilloma containing human papilloma virus type 18 and 31/33/35-positive preceded a recurrence combined with carcinoma by 2 years; this recurrent papilloma and the carcinoma were also positive for human papilloma virus 18 DNA. We suggest that human papilloma virus typing should be performed in every squamous cell papilloma of bronchus. Patients with papillomas exhibiting human papilloma virus 16 or 18 positivity are at high risk for the development of squamous cell carcinoma. Furthermore, virus typing may be of prognostic importance in relation to the development of squamous carcinoma.     

Prevalence of alpha-papillomavirus genotypes in cervical squamous intraepithelial lesions and invasive cervical carcinoma in the Italian population

The aim of the present investigation was to define the spectrum of mucosotropic human papillomaviruses among 414 Italian women with normal cervices (n = 183), low- and high-grade cervical squamous intraepithelial lesions (n = 101 and 65, respectively), and invasive squamous cervical carcinomas (n = 65). Human papillomaviruses were detected by broad spectrum consensus-primer-pairs MY09/MY11 and GP5+/GP6+-based polymerase chain reaction using three amplification methods and were characterized by nucleotide sequence analysis. The prevalence rates of HPV infections was 19.7%, 63.4%, 80%, and 81.5% in patients with normal cervices, low-grade, and high-grade squamous intraepithelial lesions, and cervical carcinomas, respectively. Among the 205 HPV-positive patients, a total of 31 mucosal HPV genotypes were identified of which 16 types, epidemiological classified as high-risk viruses (HPV16, 18, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 66, 68, 73, and 82), have been found in 16.9%, 50.1%, 69.2%, and 78.5% of normal cervix, low-, and high-grade cervical squamous intraepithelial lesions, and cervical carcinoma groups, respectively. As expected, the HPV16 was the most represented viral type in all groups examined with frequency rates ranging from 8.7% in normal subjects to 58.5% in invasive carcinoma patients. Ten epidemiologically defined low-risk HPV types (HPV6, 11, 42, 54, 61, 70, 71, 72, 81, 83) were detected in 2.7%, 7.9%, and 6.1% of normal cervix, low-, and high-grade cervical squamous intraepithelial lesions, respectively, and in none of invasive carcinomas. Furthermore, five unknown risk viruses were detected in 3% of low-grade cervical squamous intraepithelial lesions (HPV30, 32, 67), in 3.1% of high-grade cervical squamous intraepithelial lesions (HPV62, 90), and in 1.5% of cervical carcinomas (HPV62). Larger epidemiological screening studies, with PCR amplification and followed by either hybridization-based procedures against sequence targets of all known HPV types or sequence analysis studies, are needed in order to assess the epidemiological risk of less represented HPV types, to identify unknown viruses, and to monitor the future eventual spread of unusual viral types related to vaccination programs and/or population mobility.