Genetic and epigenetic changes in vulvar squamous cell carcinoma and its precursor lesions: a review of the current literature

Incidence and Risk Factors for Recurrence and Progression of HPV-Independent Vulvar Intraepithelial Neoplasia

OBJECTIVES

Human papillomavirus (HPV)-independent vulvar intraepithelial neoplasia (VIN) is a rare yet aggressive precursor lesion of vulvar cancer. Our objectives were to estimate its long-term incidence, the risk of recurrent disease and progression to vulvar cancer, and risk factors thereof.

MATERIALS AND METHODS

Patients with HPV-independent VIN between 1991 and 2019 in a selected region were identified from the Dutch Nationwide Pathology Databank (Palga). Data were collected from the pathology reports. Crude and European age-standardized incidence rates were calculated for 10-year periods. Kaplan-Meier analyses were performed to determine the cumulative recurrence and cancer incidence, followed by Cox regression analyses to identify associated risk factors.

RESULTS

A total of 114 patients were diagnosed with solitary HPV-independent VIN without prior or concurrent vulvar cancer. The European age-standardized incidence rate increased from 0.09 to 0.69 per 100,000 women-years between 1991-2010 and 2011-2019. A cumulative recurrence and cancer incidence of 29% and 46% were found after 8 and 13 years of follow-up, respectively. Nonradical surgery was identified as the only independent risk factor for recurrent HPV-independent VIN. Risk factors associated with progression to cancer were increasing age and a mutant p53 immunohistochemical staining pattern.

CONCLUSIONS

The incidence of detected HPV-independent VIN has substantially increased the last decade and the subsequent recurrence and vulvar cancer risks are high. Although HPV-independent VIN may present as a wide morphologic spectrum, surgical treatment should aim for negative resection margins followed by close surveillance, especially for p53 mutant lesions.

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.

Genomic characterization of vulvar squamous cell carcinoma reveals differential gene expression based on clinical outcome

OBJECTIVE

The greatest challenge in the management of vulvar squamous cell carcinoma (VSCC) is treatment of recurrent disease where options for surgery and radiation have been exhausted, or treatment of disease where distant metastasis is present. Identification of mutations differentially expressed between tumor from patients who died of aggressive disease and tumor from patients with an indolent course could reveal novel prognostic indicators and guide development of therapeutic drugs.

METHODS

From 202 consecutive patients with VSCC, patients who recurred and died of disease (group A) were identified and matched by age, tumor size, depth of invasion and nodal status with those whose disease did not recur (group B). Tumors from 21 patients were subjected to whole exome sequencing of DNA and RNA, immunohistochemistry (IHC) antibodies of PD-L1 and P16, and in-situ hybridization (ISH) for high-risk HPV.

RESULTS

Analysis of DNA and RNA revealed six genes that were strongly differentially expressed between group A and B: TGM3, ACVR2A, ROS1, NFEL2, CCND1 and BCL6. Clinically relevant DNA mutations were significantly greater in group A versus B: 7 vs 2.3 mutations per patient. The most common genomic alterations were mutations in TP53 and the promoter region of TERT. Other common genomic events include alterations of FAT1, CDKN2A, PIK3CA, CCND1, and LRP1B. All samples were MSI stable and tumor mutational burden (TMB) was similar in groups A and B. Most VSCC specimens (81%) were positive for PD-L1.

CONCLUSIONS

ACVR2A and TGM3 are significantly under-expressed in tumors with poor outcome, suggesting they may play a role in tumor suppression. Clinical outcome of VSCC appears independent of MSI, TMB, or PD-L1 status.

The expression of corticotropin-releasing hormone family peptides in premalignant and malignant vulvar lesions

OBJECTIVES

To examine the relation of corticotropin-releasing hormone (CRH) family peptides with inflammatory processes and oncogenesis, emphasizing in vulvar inflammatory, premalignant and malignant lesions, as well as to investigate the possibility of lesion cells immunoescaping, utilizing FAS/FAS-L complex.

METHODS

Immunohistochemical expression of CRH, urocortin (UCN), FasL and their receptors CRHR1, CRHR2 and Fas was studied in vulvar tissue sections obtained from patients with histologically confirmed diagnosis of lichen, vulvar intraepithelial neoplasia (VIN) and vulvar squamous cell carcinoma (VSCC). The patient cohort was selected from a tertiary teaching Hospital in Greece, between 2005 and 2015. For each of the disease categories, immunohistochemical staining was evaluated and the results were statistically compared.

RESULTS

A progressive increase of the cytoplasmic immunohistochemical expression of CRH and UCN, from precancerous lesions to VSCC was observed. A similar increase was detected for Fas and FasL expression. Nuclear localization of UCN was demonstrated in both premalignant and VSCC lesions, with staining being significantly intensified in carcinomas, particularly in the less differentiated tumor areas or in the areas at invasive tumor front.

CONCLUSIONS

Stress response system and CRH family peptides seem to have a role in inflammation maintenance and progression of vulvar premalignant lesions to malignancy. It seems that stress peptides may locally modulate the stroma through Fas/FasL upregulation, possibly contributing to vulvar cancer development.

Time trends in human papillomavirus prevalence and genotype distribution in vulvar carcinoma in Norway

INTRODUCTION

Approximately 25%-43% of all vulvar carcinomas are associated with human papillomavirus (HPV). In many countries, vulvar carcinoma incidence rates are increasing, possibly due to greater HPV exposure. However, studies exploring changes in HPV prevalence and genotype distribution in vulvar carcinoma over time are scarce. Our aim was to evaluate time trends in HPV prevalence and genotype distribution in vulvar squamous cell carcinoma in an unselected, nationwide sample of Norwegian women. Further, we explored clinical and histopathological aspects in relation to HPV status and investigated whether HPV status was associated with survival.

MATERIAL AND METHODS

All vulvar squamous cell carcinoma cases from 1970-1975 and 2000-2005 were extracted from the Cancer Registry of Norway and corresponding tissue blocks were retrieved. After detailed histology review, HPV testing was conducted using real-time TaqMan PCR. Overall survival rates were calculated using the Kaplan-Meier method. Multivariable Cox regression analysis was performed to estimate hazard ratios adjusted for age at diagnosis, stage and diagnostic period.

RESULTS

Histological review was performed on 352 vulvar squamous cell carcinoma cases. We were able to obtain valid HPV analysis results for 282 cases, Overall, 29.8% (95% CI 24.5%-35.5%) of cases were high-risk HPV (hrHPV)-positive. When comparing the two periods, we found that the percentage of hrHPV-positive tumors increased significantly from 23% (95% CI 16.0%-31.4%) in 1970-1975 to 35.3% (95% CI 27.8%-43.3%) in 2000-2005 (P = 0.025). The predominant genotypes were HPV 16 (73%), HPV 33 (21%), and HPV 18 (6%), with similar distributions in both periods. In the more recent cohort, several additional genotypes were detected: HPV 6, 11, 39, 45, 52, 58 and 66 were found in smaller percentages, ranging from 1.8% to 3.6%. In univariate analysis, patients with HPV-positive tumors showed improved overall survival compared with patients with HPV-negative tumors (hazard ratio [HR] 0.65, 95% CI 0.48-0.86).

CONCLUSIONS

The prevalence of HPV in vulvar squamous cell carcinomas in Norway was significantly higher in 2000-2005 than in 1970-1975. The three predominant genotypes were HPV 16, 33 and 18 in both time periods. However, several other HPV genotypes have emerged over the last decades. HPV-positivity was associated with better overall survival.

Long-Term Transcriptomic Changes and Cardiomyocyte Hyperpolyploidy after Lactose Intolerance in Neonatal Rats

Many cardiovascular diseases originate from growth retardation, inflammation, and malnutrition during early postnatal development. The nature of this phenomenon is not completely understood. Here we aimed to verify the hypothesis that systemic inflammation triggered by neonatal lactose intolerance (NLI) may exert long-term pathologic effects on cardiac developmental programs and cardiomyocyte transcriptome regulation. Using the rat model of NLI triggered by lactase overloading with lactose and the methods of cytophotometry, image analysis, and mRNA-seq, we evaluated cardiomyocyte ploidy, signs of DNA damage, and NLI-associated long-term transcriptomic changes of genes and gene modules that differed qualitatively (i.e., were switched on or switched off) in the experiment vs. the control. Our data indicated that NLI triggers the long-term animal growth retardation, cardiomyocyte hyperpolyploidy, and extensive transcriptomic rearrangements. Many of these rearrangements are known as manifestations of heart pathologies, including DNA and telomere instability, inflammation, fibrosis, and reactivation of fetal gene program. Moreover, bioinformatic analysis identified possible causes of these pathologic traits, including the impaired signaling via thyroid hormone, calcium, and glutathione. We also found transcriptomic manifestations of increased cardiomyocyte polyploidy, such as the induction of gene modules related to open chromatin, e.g., "negative regulation of chromosome organization", "transcription" and "ribosome biogenesis". These findings suggest that ploidy-related epigenetic alterations acquired in the neonatal period permanently rewire gene regulatory networks and alter cardiomyocyte transcriptome. Here we provided first evidence indicating that NLI can be an important trigger of developmental programming of adult cardiovascular disease. The obtained results can help to develop preventive strategies for reducing the NLI-associated adverse effects of inflammation on the developing cardiovascular system.

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

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

Neoadjuvant chemotherapy for patients with locally advanced vulvar cancer

PURPOSE OF REVIEW

Studies on treatment options for patients with locally advanced vulvar cancer (LAVC) are scarce, and high-level evidence for a primary treatment choice is lacking. Furthermore, current treatment options are associated with extensive morbidity and high complication rates. More effective treatment options are urgently needed. This review describes current treatment possibilities, focusing on literature regarding neoadjuvant chemotherapy (NACT) followed by surgery.

RECENT FINDINGS

Although data are heterogeneous and limited, NACT followed by surgery might be an effective and well tolerated treatment alternative associated with lower morbidity compared with current treatment options, such as excenterative surgery or definitive chemoradiation.

SUMMARY

Up until now, several studies describe an overall response rate of 40-86%. Surgery turned out to be possible in 40-90% of the LAVC patients who received NACT. Prospective studies on the efficacy and safety of NACT followed by surgery with a homogeneous chemotherapy regimen are urgently awaited. NACT should, at this point, still be considered investigational.

Gynecologic Cancer Risk and Genetics: Informing an Ideal Model of Gynecologic Cancer Prevention

Individuals with proven hereditary cancer syndrome (HCS) such as BRCA1 and BRCA2 have elevated rates of ovarian, breast, and other cancers. If these high-risk people can be identified before a cancer is diagnosed, risk-reducing interventions are highly effective and can be lifesaving. Despite this evidence, the vast majority of Canadians with HCS are unaware of their risk. In response to this unmet opportunity for prevention, the British Columbia Gynecologic Cancer Initiative convened a research summit “Gynecologic Cancer Prevention: Thinking Big, Thinking Differently” in Vancouver, Canada on 26 November 2021. The aim of the conference was to explore how hereditary cancer prevention via population-based genetic testing could decrease morbidity and mortality from gynecologic cancer. The summit invited local, national, and international experts to (1) discuss how genetic testing could be more broadly implemented in a Canadian system, (2) identify key research priorities in this topic and (3) outline the core essential elements required for such a program to be successful. This report summarizes the findings from this research summit, describes the current state of hereditary genetic programs in Canada, and outlines incremental steps that can be taken to improve prevention for high-risk Canadians now while developing an organized population-based hereditary cancer strategy.

Influence of Photodynamic Therapy on Lichen Sclerosus with Neoplastic Background

Background: Lichen sclerosus is the most common nonmalignant vulvar disease with morbidity in postmenopausal age. The first line of treatment is corticosteroid therapy. In case of insufficiency, tacrolimus or pimecrolimus can be provided. Photodynamic therapy (PDT) can be used as alternative way of treatment while symptoms recurrent despite other methods. Methods: the analyzed population of 182 women with diagnosis of lichen sclerosus treated using PDT was divided into three groups: patients with neoplastic disease or intraepithelial neoplasia; those with a positive family history of neoplastic disease; and a control group with no neoplastic disease and no familial history of neoplastic diseases. Results: Reduction of vulvar changes was assessed in the whole vulva in the groups as 21.9%, 21.2% and 21.8%, respectively. The most frequent symptom, itching, was reported to decrease in all groups, 39.3%, 35.5% and 42.5%, respectively. Improvement of quality of life was assessed in 91.3% of the whole group, stabilization of lichen sclerosus in 7.1% and progression in 1.6%. Conclusions: Photodynamic therapy gives positive results in most cases. Improvement after PDT is observed in objective vulvoscopic assessment and in subjective patients’ opinions. Neoplastic disease in the past can influence the effectiveness of PDT.

Immunotherapeutic Approaches for the Treatment of HPV-Associated (Pre-)Cancer of the Cervix, Vulva and Penis

Human papillomavirus (HPV) infection drives tumorigenesis in almost all cervical cancers and a fraction of vulvar and penile cancers. Due to increasing incidence and low vaccination rates, many will still have to face HPV-related morbidity and mortality in the upcoming years. Current treatment options (i.e., surgery and/or chemoradiation) for urogenital (pre-)malignancies can have profound psychosocial and psychosexual effects on patients. Moreover, in the setting of advanced disease, responses to current therapies remain poor and nondurable, highlighting the unmet need for novel therapies that prevent recurrent disease and improve clinical outcome. Immunotherapy can be a useful addition to the current therapeutic strategies in various settings of disease, offering relatively fewer adverse effects and potential improvement in survival. This review discusses immune evasion mechanisms accompanying HPV infection and HPV-related tumorigenesis and summarizes current immunotherapeutic approaches for the treatment of HPV-related (pre-)malignant lesions of the uterine cervix, vulva, and penis.

Molecular landscape of vulvovaginal squamous cell carcinoma: new insights into molecular mechanisms of HPV-associated and HPV-independent squamous cell carcinoma

Squamous cell carcinomas of the lower female genital tract may be human papillomavirus-associated or independent. We studied the HPV status, mutational repertoire, histology, and clinical data of 28 samples from 26 patients, 65% with a vulvar primary and 35% with a vaginal primary. These represented invasive vulvovaginal squamous cell carcinomas that underwent clinical tumor-normal targeted massively parallel sequencing analysis. HPV status was determined using the HPV high-risk RNA ISH assay and/or by MSK-IMPACT. Eleven patients had HPV-associated squamous cell carcinoma (four vulvar and seven vaginal) and 15 patients had HPV-independent SqCC (13 vulvar and 2 vaginal). Well-differentiated squamous cell carcinomas were always HPV-independent. HPV-independent moderately and poorly differentiated carcinomas frequently had alterations in the NOTCH signaling pathway (6/7), which were also associated with increased tumor budding (P: 0.002). HPV-associated vulvovaginal squamous cell carcinoma had PIK3CA activating mutations (7/11, 64%) as the most common genomic event, while TERT gene alterations, mainly TERT promoter mutations (14/15 cases, 93%) featured significantly in HPV-independent carcinomas. Other common abnormalities in HPV-independent tumors were TP53 mutations (13/15, 87%), CDKN2A alterations (10/15, 67%), and NOTCH1 and FAT1 mutations (7/15, 47% each). A subset of both HPV-associated and -independent tumors had NOTCH pathway alterations (6/11, 55% and 10/15, 67% respectively), but different genes in this pathway were altered in these tumors. In summary, TERT, TP53, CDKN2A, and NOTCH1 gene alterations strongly point away from an HPV-driven process (odds ratios: 0.01, 0.07, 0, and 0, respectively with p values < 0.02 for all four genes), while PIK3CA activating mutations without the other mutations strongly favors an HPV-driven tumor (odds ratio: 10.12, p value: 0.016). HPV-independent carcinomas are more likely to be moderately-poorly differentiated with intermediate to high tumor cell budding. Cancer cell fraction analysis of HPV-independent squamous carcinomas suggests that TERT and/or NOTCH1 alterations along with TP53 alterations can be the initiating event in these tumors.

Management of Advanced Squamous Cell Carcinoma of the Vulva

Simple Summary

Vulvar cancer is a rare gynaecological malignancy that has an increasing incidence, particularly in younger women. Early vulvar cancer can be treated and cured with surgical excision. Approximately 30% of women present with advanced disease, which requires treatment either with mutilating surgery or a combination of chemotherapy and radiotherapy, which is an effective treatment but has many side effects. Current research is focused on new less morbid approaches to treatment, in which drugs that target various steps on the biological pathway from pre-cancer to cancer are used, with the aim of preventing the growth of vulvar cancers. This review is an update of the current management of women with advanced vulvar cancer.

Abstract

Vulvar cancer is a rare gynaecological malignancy, accounting for 2–5% of cancers of the female genital tract. Squamous cell carcinoma is the most frequently occurring subtype and, historically, has been a disease of older post-menopausal women, occurring with a background of lichen sclerosus and other epithelial conditions of the vulvar skin that may be associated with well-differentiated vulvar intra-epithelial neoplasia (dVIN). An increase in human papillomavirus (HPV) infections worldwide has led to an increase in vulvar squamous carcinomas in younger women, resulting from HPV-associated high-grade vulvar squamous intra-epithelial lesions (vHSIL). Surgical resection is the gold standard for the treatment of vulvar cancer. However, as approximately 30% of patients present with locally advanced disease, which is either irresectable or will require radical surgical resection, possibly with a stoma, there has been a need to investigate alternative forms of treatment such as chemoradiation and targeted therapies, which may minimise the psychosexual morbidity of radical surgery. This review aims to provide an update on management strategies for women with advanced vulvar cancer. It is hoped that investigation of the molecular biologies of the two different pathways to vulvar squamous cell carcinoma (HPV-associated and non-HPV-associated) will lead to the development of targeted therapeutic agents.

The Vulvar Immunohistochemical Panel (VIP) Project: Molecular Profiles of Vulvar Squamous Cell Carcinoma

Simple Summary

This study investigated the immunohistochemical expression of 14 biological markers as potential prognostic/therapeutic factors in vulvar squamous cell carcinoma, comparing 53 node-negative (Group A) and 48 node-positive (Group B) patients. Our results show a significantly higher p16 expression (surrogate of HPV-related tumors) in the vulvar samples of non-metastatic patients. In Group B, PD-L1 positivity and high EGFR expression were found in the vast majority of vulvar and/or nodal specimens. VEGF showed strong/moderate-diffuse expression in almost 14% of all vulvar samples. A mutated p53 and over-expressed PD-L1 showed a significant association with nodal metastasis. Our results support a potential role of immune checkpoint inhibitors and anti-VEGF and anti-EGFR drugs, especially in patients with worse prognosis (metastatic, HPV-independent). A panel including EGFR, VEGF, PDL1, p16, and p53 might be performed routinely in primary tumor and repeated in case of lymph node metastases to identify changes in marker expression.

Abstract

Introduction: The study’s aim was to investigate the immunohistochemical (IHC) expression of biological markers as potential prognostic/therapeutic factors in vulvar squamous cell carcinoma (VSCC). Methodology: A series of 101 patients surgically treated at our center from 2016 to 2020 were retrospectively enrolled: 53 node-negative (Group A) and 48 node-positive (Group B). A total of 146 samples, 101 from primary tumor (T) and 45 from nodal metastases (N), were investigated. The IHC panel included: p16, p53, MLH1, MSH2, MSH6, PMS2, PD-L1, CD3, HER2/neu, ER, PR, EGFR, VEGF, and CD31. The reactions were evaluated on qualitative and semi-quantitative scales. Generalized Linear Model (GLM) and cluster analysis were performed in R statistical environment. A distance plot compared the IHC panel of T with the correspondent N. Results: In Group A: p16-positive expression (surrogate of HPV-dependent pathway) was significantly higher (20.8% vs. 6.2%, p = 0.04). In Group B: PD-L1 positivity and high EGFR expression were found, respectively, in 77.1% and 97.9% patients (T and/or N). Overall, p16-negative tumors showed a higher PD-L1 expression (60.9% vs. 50.0%). In both groups: tumoral immune infiltration (CD3 expression) was mainly moderate/intense (80% vs. 95%); VEGF showed strong/moderate-diffuse expression in 13.9% of T samples; CD31, related to tumoral microvessel density (MVD), showed no difference between groups; a mutated p53 and over-expressed PD-L1 showed significant association with nodal metastasis, with Odds Ratios (OR) of 4.26 (CI 95% = 1.14–15.87, p = 0.03) and 2.68 (CI 95% = 1.0–7.19, p < 0.05), respectively; since all mismatch repair proteins (MMR) showed a retained expression and ER, PR, and HER2/neu were negative, they were excluded from further analysis. The cluster analysis identified three and four sub-groups of molecular profiles, respectively, in Group A and B, with no difference in prognosis. The molecular signature of each N and corresponding T diverged significantly in 18/41 (43.9%) cases. Conclusions: Our results support a potential role of immune checkpoint inhibitors and anti-VEGF and anti-EGFR drugs especially in patients with worse prognosis (metastatic, HPV-independent). A panel including EGFR, VEGF, PDL1, p16, and p53 might be performed routinely in primary tumor and repeated in case of lymph node metastases to identify changes in marker expression.

Transcriptome Analysis in Vulvar Squamous Cell Cancer

Simple Summary

The number of women, especially younger women, diagnosed with vulvar cancer, has been rising mainly due to the infection with human papilloma virus (HPV) over the last years. In contrast to other tumor entities, limited information on the underlying genetic changes is available, and thus treatment advances, especially the development of personalized treatments, are hampered. We aimed to explore the RNA expression profiles in a group of 24 vulvar cancer samples in order to detect potential prognostic markers and therapeutic targets in order to establish to a more profound understanding of vulvar cancer carcinogenesis.

Abstract

To date, therapeutic strategies in vulvar squamous cell carcinoma (VSCC) are lacking molecular pathological information and targeted therapy hasn’t been approved in the treatment of VSCC, yet. Two etiological pathways are widely accepted: HPV induced vs. HPV independent, associated with chronic skin disease, often harboring TP53 mutations (mut). The aim of this analysis was to analyze the RNA expression patterns for subtype stratification on VSCC samples that can be integrated into the previously performed whole exome sequencing data for the detection of prognostic markers and potential therapeutic targets. We performed multiplex gene expression analysis (NanoString) with 770 genes in 24 prior next generation sequenced samples. An integrative data analysis was performed. Here, 98 genes were differentially expressed in TP53mut vs. HPV+ VSCC, in the TP53mut cohort, where 56 genes were upregulated and 42 were downregulated in comparison to the HPV+ tumors. Aberrant expression was primarily observed in cell cycle regulation, especially in HPV+ disease. Within the TP53mut group, a distinct cluster was identified that was correlated to a significantly worse overall survival (p = 0.017). The RNA expression profiles showed distinct patterns with regard to the known VSCC subtypes and could potentially enable further subclassification in the TP53mut groups

Epigenetic Dysregulations in Merkel Cell Polyomavirus-Driven Merkel Cell Carcinoma

Merkel cell polyomavirus (MCPyV) is a small DNA virus with oncogenic potential. MCPyV is the causative agent of Merkel Cell Carcinoma (MCC), a rare but aggressive tumor of the skin. The role of epigenetic mechanisms, such as histone posttranslational modifications (HPTMs), DNA methylation, and microRNA (miRNA) regulation on MCPyV-driven MCC has recently been highlighted. In this review, we aim to describe and discuss the latest insights into HPTMs, DNA methylation, and miRNA regulation, as well as their regulative factors in the context of MCPyV-driven MCC, to provide an overview of current findings on how MCPyV is involved in the dysregulation of these epigenetic processes. The current state of the art is also described as far as potentially using epigenetic dysregulations and related factors as diagnostic and prognostic tools is concerned, in addition to targets for MCPyV-driven MCC therapy. Growing evidence suggests that the dysregulation of HPTMs, DNA methylation, and miRNA pathways plays a role in MCPyV-driven MCC etiopathogenesis, which, therefore, may potentially be clinically significant for this deadly tumor. A deeper understanding of these mechanisms and related factors may improve diagnosis, prognosis, and therapy for MCPyV-driven MCC.

Synchronous detection of pancreatic adenocarcinoma and paraganglioma in a Whipple resection specimen

We report a case of a pancreatic ductal adenocarcinoma (PDAC) presenting synchronously with a paraganglioma (PGL) in a Whipple reaction specimen. The patient was a 72-year-old female with a history of breast and vulvar cancer. The simultaneous occurrence of two synchronous tumours in the pancreas was striking. Due to the presence of PGL and multiple meta- and synchronous tumours, the patient was referred to genetic counselling. Tumour tissue from the vulvar carcinoma, the PDAC and the PGL was analysed by targeted next-generation sequencing (NGS) of 161 cancer-related genes and by whole exome sequencing (WES). Peripheral blood was also examined by NGS and WES. These genetic analyses revealed germline polymorphisms in AXIN2 (NM_004655.4:c 0.2272 G>A; p.Ala758Thr), BRCA2 (NM_000059.3:c.9976 A>T; p.Lys3326Ter), NCOR1 (NM_006311.4:c 0.6544 G>A; p.Ala2182Thr) and SPTA1 (NM_003126.3:c 0.373 G>A; p.Ala125Thr) and somatic mutations of KRAS (NM_033360.3;c 0.35 G>A; p.Gly12Asp) and TP53 (NM_000546.5; c.602delT; p.Leu201CysfsTer46) in the PDAC and of TP53 (NM_000546.5; c 0.733 G>A; p.Gly245Ser) and TERT (NM_198253.2; c.-124 C>T; promotor region) in the vulvar carcinoma. Breast carcinoma tissue was not available for genetic analysis. The results of the genetic analyses did not explain the presence of multiple tumours in this patient, despite a slightly increased risk of breast cancer associated with the identified BRCA2 polymorphism. To our knowledge, this is the first report of the synchronous occurrence of PDAC and PGL. This case emphasizes the importance of thorough macroscopic examination of pancreatic resection specimens, as coexisting neoplasms may otherwise be missed.

Vulvar Lichen Sclerosus from Pathophysiology to Therapeutic Approaches: Evidence and Prospects

Vulvar lichen sclerosus (VLS) is a chronic, distressing, inflammatory disease with an enormous impact on quality of life. Treatment goals are relieving symptoms, reversing signs and preventing anatomical changes. Despite the availability of numerous therapeutic options, treatment outcome may not be entirely satisfactory and a definitive cure does not exist. This may be due to the fact that the exact VLS etiopathogenesis remains unknown. The objectives of this paper were to review the most up-to-date knowledge on VLS etiopathogenesis and to consider the available therapies through the lens of a plausible pathogenetic model. An electronic search on both VLS etiopathogenesis and its treatment was performed using the National Library of Medicine PubMed database. Based on current knowledge, it is conceivable that various, heterogeneous environmental factors acting on a genetic background trigger an autoimmune, Th-1 response, which leads to a chronic inflammatory state. This, in turn, can determine both tissue and micro-vascular injury and activation of signaling pathways involved in fibroblast and collagen metabolism. This pathogenetic sequence may explain the effectiveness of anti-inflammatory treatments, mostly topical corticosteroids, in improving VLS clinical-pathological changes. Further deepening of the disease pathways will presumably allow key mediators to become new therapeutic targets and optimize the available treatments.

Exploring Differentially Methylated Genes in Vulvar Squamous Cell Carcinoma

Simple Summary

Vulvar squamous cell carcinoma (VSCC) is the most common form of vulvar malignancy, and its incidence has increased in recent years. For better diagnosis and prognostication, and to expand available treatment options, molecular characterization of VSCC is crucial. We sought to identify aberrations in DNA methylation in VSCC, as this has been implicated in the development of several cancers. To this end, we performed genome-wide methylation sequencing on a set of VSCC and normal vulvar tissue using the Infinium MethylationEPIC BeadChip array. We detected 199 genes to be differentially methylated in VSCC compared to normal vulvar tissue. Of these, 194 genes were hyper-methylated, which leads to a loss of function of the genes. As most of these genes are involved in transcription regulator activity, our results suggest that disruption of this process plays an important role in VSCC development.

Abstract

DNA methylation is the most widely studied mechanism of epigenetic modification, which can influence gene expression without alterations in DNA sequences. Aberrations in DNA methylation are known to play a role in carcinogenesis, and methylation profiling has enabled the identification of biomarkers of potential clinical interest for several cancers. For vulvar squamous cell carcinoma (VSCC), however, methylation profiling remains an under-studied area. We sought to identify differentially methylated genes (DMGs) in VSCC, by performing Infinium MethylationEPIC BeadChip (Illumina) array sequencing, on a set of primary VSCC (n = 18), and normal vulvar tissue from women with no history of vulvar (pre)malignancies (n = 6). Using a false-discovery rate of 0.05, beta-difference (Δβ) of ±0.5, and CpG-island probes as cut-offs, 199 DMGs (195 hyper-methylated, 4 hypo-methylated) were identified for VSCC. Most of the hyper-methylated genes were found to be involved in transcription regulator activity, indicating that disruption of this process plays a vital role in VSCC development. The majority of VSCCs harbored amplifications of chromosomes 3, 8, and 9. We identified a set of DMGs in this exploratory, hypothesis-generating study, which we hope will facilitate epigenetic profiling of VSCCs. Prognostic relevance of these DMGs deserves further exploration in larger cohorts of VSCC and its precursor lesions.

Molecular Landscape of Vulvar Squamous Cell Carcinoma

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

Distinct Patterns of Myeloid Cell Infiltration in Patients With hrHPV-Positive and hrHPV-Negative Penile Squamous Cell Carcinoma: The Importance of Assessing Myeloid Cell Densities Within the Spatial Context of the Tumor

Comprehensive analysis of tumor infiltrating myeloid cells in the tumor microenvironment of penile squamous cell carcinoma (PSCC) is lacking. In this retrospective study, for the first time, PSCC resection specimens (N = 103) were annotated into the following compartments: intratumoral tumor (IT Tumor), intratumoral stroma (IT Stroma), peritumoral tumor (PT Tumor) and peritumoral stroma (PT Stroma) compartments. We then quantified CD14+, CD68+ and CD163+ myeloid cells within these compartments using an image analysis software and assessed their association with various clinical parameters, including high-risk human papillomavirus (hrHPV) status. In the total cohort, hrHPV status, grade of differentiation, age and tumor size were associated with myeloid cell densities. hrHPV⁺ tumors had higher infiltration rates of CD14+, CD68+ and CD163+ myeloid cells in the IT tumor compartment (p < 0.001, for all) compared to hrHPV^- tumors. Furthermore, when examining the association between compartment-specific infiltration and differentiation grade, increased myeloid cell densities in the IT tumor compartment were associated with a more advanced histological grade (p < 0.001, for all). This association remained significant when the hrHPV^- cohort (N = 60) was analyzed (CD14+ p = 0.001; CD68+ p < 0.001; CD163+ p = 0.004). Subgroup analysis in the hrHPV⁺ group (N = 43) showed that high infiltration rates of CD68+ and CD163+ cells in the PT tumor compartment were associated with lymph node (LN) metastasis (p = 0.031 and p = 0.026, respectively). Regarding the association between myeloid cell densities and disease-specific survival, the risk of death was found to decrease slightly as the number of myeloid cells in the IT tumor compartment increased (CD14+ p = 0.04; CD68+ p = 0.05; CD163+ p = 0.02). However, after adjusting for hrHPV, no independent association between myeloid densities and disease-specific survival were found. Altogether, these findings demonstrate the importance of assessing myeloid cell densities within the spatial context of the tumor. Further studies are needed to unravel the specific phenotype of myeloid cells residing in the different compartments, their effect on clinical parameters and the impact of hrHPV on the recruitment of myeloid cell populations in PSCC.

p53 and p16 expression profiles in vulvar cancer: a translational analysis by the Arbeitsgemeinschaft Gynäkologische Onkologie Chemo and Radiotherapy in Epithelial Vulvar Cancer study group

BACKGROUND

There are 2 known pathways for tumorigenesis of vulvar squamous cell carcinoma-a human papillomavirus-dependent pathway characterized by p16 overexpression and a human papillomavirus-independent pathway linked to lichen sclerosus, characterized by TP53 mutation. A correlation of human papillomavirus dependency with a favorable prognosis has been proposed.

OBJECTIVE

The objective of the study was to further understand the role of human papillomavirus and p53 status in vulvar squamous cell carcinoma and characterize its clinical relevance.

STUDY DESIGN

The Arbeitsgemeinschaft Gynaecological Oncology Chemo and Radiotherapy in Epithelial Vulvar Cancer-1 study is a retrospective cohort study of 1618 patients with primary vulvar squamous cell carcinoma Fédération Internationale de Gynécologie et d'Obstétrique stage ≥1B treated at 29 gynecologic cancer centers in Germany between 1998 and 2008. For this translational substudy, formalin-fixed paraffin-embedded tissue was collected. A tissue microarray was constructed (n=652 samples); p16 and p53 expression was determined by immunohistochemistry. Human papillomavirus status and subtype were analyzed by polymerase chain reaction.

RESULTS

p16 immunohistochemistry was positive in 166 of 550 tumors (30.2%); p53 staining in 187 of 597 tumors (31.3%). Only tumors with available information regarding p16 and p53 immunohistochemistry and without p53 silent expression pattern were further analyzed (n=411); 3 groups were defined: p53+ (n=163), p16+/p53- (n=132), and p16-/p53- (n=116). Human papillomavirus DNA was detected in 85.6% of p16+/p53- tumors; human papillomavirus-16 was the most common subtype (86.3%). Patients with p16+ tumors were younger (64 vs 72 years for p53+, respectively, 69 years for p16-/p53- tumors; P<.0001) and showed lower rates of lymph-node involvement (28.0% vs 42.3% for p53+, respectively, 30.2% for p16-/p53- tumors; P=.050). Notably, 2-year-disease-free and overall survival rates were significantly different among the groups: disease-free survival, 47.1% (p53+), 60.2% (p16-/p53-), and 63.9% (p16+/p53-) (P<.001); overall survival, 70.4% (p53+), 75.4% (p16-/p53-), and 82.5% (p16+/p53-) (P=.002). In multivariate analysis, the p16+/p53- phenotype showed a consistently improved prognosis compared with the other groups (hazard ratio, 0.66; 95% confidence interval, 0.44-0.99; P=.042).

CONCLUSION

p16 overexpression is associated with an improved prognosis whereas p53 positivity is linked to an adverse outcome. Our data support the hypothesis of a clinically relevant third subgroup of vulvar squamous cell carcinoma with a p53-/p16- phenotype showing an intermediate prognosis that needs to be further characterized.

Localized amyloidosis in usual-type vulvar intraepithelial neoplasia High-risk HPV association and potential clinical significance. A series of 45 cases

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Localized amyloidosis is only identified in Usual-type HPV-associated VINs.

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Subtypes of hrHPV in both localized amyloidosis and non-amyloid cases are similar.

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VINs with localized amyloidosis appear to have a better prognosis.

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Amyloid deposits persisted even after regression of VINs.

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Localized amyloid deposits in VINs may be a manifestation of body’s defense mechanism.

Localized cutaneous amyloidosis was reported recently in association with vulvar squamous intraepithelial neoplasia (VIN). High-risk human papillomavirus (hrHPV) type 16 is the most commonly reported subtype found in usual-type VIN. However, it is unknown whether any hrHPV subtype(s) is/are prevalent in simultaneous squamous intraepithelial lesions and localized amyloidosis in the same individual - the subject matter of this report. To observe the potential clinical significance, study cases were followed and compared to usual-type VINs without amyloid deposition. Of 45 patients of usual-type VINs associated with amyloidosis, 33 had detectable hrHPV, and 12 were negative. HPV 16 alone or in combination with HPV 31 accounted for 72%, HPV 51 alone accounted for 2% of the cases, and 26% were negative for hrHPV. Lack of demonstrable hrHPV in a significant proportion of cases (26%) raises the possibility of a novel or presently undetected hrHPV subtype. Five of the total 22 (23%) patients with amyloid had either Squamous cell carcinoma or high-grade VIN on follow-up. In contrast, 14 of 18 (78%) patients exhibiting lesions without amyloid had disease on follow-up. These findings may indicate that amyloid deposition may represent a feature of regression or a potential favorable prognostic indicator.

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

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

Diagnostic Criteria for Differentiated Vulvar Intraepithelial Neoplasia and Vulvar Aberrant Maturation

OBJECTIVE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Molecular events in the pathogenesis of vulvar squamous cell carcinoma

Vulvar squamous cell carcinomas (VSCC), which constitute over 90% of vulvar malignancies in adults, are classifiable into 2 subgroups that are mostly clinicopathologically distinct, a classification that is fundamentally based whether or not the tumors are HPV-mediated. In this review, we aim to summarize the recent advances in the understanding of molecular events in the pathogenesis of VSCC, including common and targetable mutations, copy number alterations, epigenetics, noncoding RNAs, and tumor immune microenvironment, which may provide insight into the future management of the disease. These events show substantial differences between the 2 subgroups, although significant areas of overlap exist. Recurrent, driver mutations appear to be substantially more prevalent in HPV(-) VSCC. TP53 mutations are the most common somatic mutations in VSCC overall, and are notably predominant in the HPV(-) VSCC, where 30-88% show a mutation. TP53 mutations are associated with worse patient outcomes, and co-mutations between TP53 and either HRAS, PIK3CA or CDKN2A appear to define subsets with even worse outcomes. A wide variety of other somatic mutations have been identified, including a subset with different mutational frequencies between HPV(+) and HPV(-) VSCC. CDKN2A mutations are common, and have been identified in 21 to 55% of HPV(-) VSCC, and in 2 to 25% of HPV(+) VSCC. Hypermethylation of CDKN2A is the most frequently reported epigenetic alteration in VSCC and the expression of some microRNAs may be associated with patient outcomes. The PTEN/PI3K/AKT/mTOR pathway is commonly altered in HPV(+) VSCC, and is accordingly potentially targetable. HPV-positivity/p16 block expression by immunohistochemistry has been found to be an independent prognostic marker for improved survival in VSCC, and may have some predictive value in VSCC patients treated with definitive radiotherapy. 22-39.3% and 68% of VSCC show EGFR amplification and protein overexpression respectively, although the prognostic and predictive value of an EGFR alteration requires additional study. Recurrent chromosomal gains in VSCCs have been found at 1q, 2q, 3q, 4p, 5p, 7p, 8p, 8q, and 12q, and there may be differential patterns of alterations depending on HPV-status. At least one-third of VSCC patients may potentially benefit from immune checkpoint inhibition therapy, based on a high frequency of PD-L1 expression or amplification, or a high tumor mutational burden. Additional studies are ultimately required to better understand the global landscape of genetic and epigenetic alterations in VSCC, and to identify and test potential targets for clinical application.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Vulvar cancer subclassification by HPV and p53 status results in three clinically distinct subtypes

OBJECTIVE

There is great need for better risk stratification in vulvar squamous cell carcinoma (VSCC). Our aim was to define the prognostic significance of stratifying VSCC based on p16 and p53 immunohistochemistry (IHC) as surrogate markers for HPV and TP53 mutations.

METHODS

A large retrospective cohort of surgically treated women with primary VSCC was used. VSCC were classified into three subtypes: HPV-positive (HPVpos), HPV-negative/p53 mutant (HPVneg/p53mut), and HPV-negative/p53 wildtype (HPVneg/p53wt). Overall survival (OS), relative survival (RS), and recurrence-free period (RFP) were depicted using the Kaplan-Meier method and survival curves for relative survival; associations were studied using univariable and multivariable Cox proportional hazard models.

RESULTS

Of the 413 VSCCs, 75 (18%) were HPVpos, 63 (15%) HPVneg/p53wt, and 275 (66%) HPVneg/p53mut VSCC. Patients with HPVneg/p53mut VSCC had worse OS and RS (HR 3.43, 95%CI 1.80-6.53, and relative excess risk (RER) of 4.02; 95%CI 1.48-10.90, respectively, and worse RFP (HR 3.76, 95%CI 2.02-7.00). HPVpos VSCC patients showed most favorable outcomes. In univariate analysis, the molecular subtype of VSCC was a prognostic marker for OS, RS and RFP (p = 0.003, p = 0.009, p < 0.001, respectively) and remained prognostic for RFP even after adjusting for known risk factors (p = 0.0002).

CONCLUSIONS

Stratification of VSCC by p16- and p53-IHC has potential to be used routinely in diagnostic pathology. It results in the identification of three clinically distinct subtypes and may be used to guide treatment and follow-up, and in stratifying patients in future clinical trials.

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

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

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

AIMS

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

METHODS AND RESULTS

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

CONCLUSION

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

Putative precancerous lesions of vulvar squamous cell carcinoma

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

Somatic Mutation Profiling in Premalignant Lesions of Vulvar Squamous Cell Carcinoma

Vulvar squamous cell carcinoma (VSCC) originates from the progression of either a high-grade squamous intraepithelial lesion (HSIL) or differentiated-type vulvar intraepithelial neoplasia (dVIN), often in a background of lichen sclerosus (LS). The mechanisms leading to the progression of these premalignant lesions to VSCC are elusive. This study aims to identify pathogenic mutations implicated in VSCC development. Using next-generation sequencing, 38 HSIL, 19 dVIN, 20 LS, of which 10 were solitary lesions and 10 with adjacent VSCC, and 10 VSCC adjacent to LS, were screened for hotspot mutations in 50 genes covered by the Ion AmpliSeq Cancer Hotspot Panel v2 Kit (Thermo Fisher Scientific). Pathogenic mutations of TP53 were the most common genetic alterations identified in 53% and 24% of dVIN and HSIL cases, respectively, followed by CDKN2A (p16) mutated in 42% and 0% of dVIN and HSIL, respectively. Seven (70%) and three (30%) of 10 cases of VSCC associated with LS carried TP53 and CDKN2A mutations, respectively, whereas neither solitary LS nor LS associated with VSCC cases harbored mutations in these genes. It appears that TP53 mutations are early events during VSCC carcinogenesis, being present in both HSIL and dVIN lesions. Our preliminary data do not support a genetic background for the notion of LS as the VSCC premalignant lesion.

Genomic characterization of vulvar squamous cell carcinoma

BACKGROUND

Despite increasing incidence, vulvar squamous cell carcinoma (VSCC) is still a rare disease. Until now, two etiological pathways have been described: a high-risk human papillomavirus (HPV)-dependent route and an HPV-independent pathway often associated with lichen sclerosus. To date, therapeutic strategies in VSCC are not influenced by molecular pathological information and therapeutic options for advanced or recurrent disease are limited.

METHODS

Whole exome sequencing of DNA, isolated from 34 VSCC samples and matched normal tissue for each individual was performed on an Illumina HiSeq4000. Short variant discovery was carried out using BWA mem and FreeBayes. Variants were annotated using ANNOVAR.

RESULTS

FIGO stages were: IB (n = 7), II (n = 11), III (n = 8), and IVA (n = 3), (n = 5 unknown). TP53 missense mutations were most commonly detected with 56% (19/34). 12/34 (35.3%) samples were HPV positive (all HPV16), HPV positivity and TP53 mutations were mutually exclusive (p < .0001). Additionally, we observed mutations in known cancer relevant genes, like NBPF1 (n = 7), MACF1 (n = 5), SYNE2 (n = 5), DOCK2 (n = 4), KMT2D (n = 4), MAP2 (n = 4), NACA (n = 4), PIK3CA (n = 4), SYNE1 (n = 4), FBWX7 (n = 3), MSH6 (n = 3), NSD1 (n = 3), POLE (n = 3), TSC2, (n = 3) and CDKN2A (n = 2), but at considerably lower frequencies. For the total cohort 1848 cancer related mutations were detected (median of 54.4 per sample).

CONCLUSIONS

The key mutation in HPV negative vulvar carcinoma affects TP53. While a multitude of cancer related mutations was detected in various samples, only few mutations recur and/or affect concurrent signaling pathways.

Vulvar Squamous Cell Carcinoma: Comprehensive Genomic Profiling of HPV+ Versus HPV- Forms Reveals Distinct Sets of Potentially Actionable Molecular Targets

PURPOSE

Vulvar squamous cell carcinoma (vSCC) encompasses two predominant variants: one associated with detectable high-risk strains of human papillomavirus (hrHPV) and a second form often occurring in the context of chronic dermatitis in postmenopausal women. Genomic assessment of a large-scale cohort of patients with aggressive vSCC may identify distinct mutational signatures.

MATERIALS AND METHODS

Tumor samples from a total of 280 patients with vSCC underwent hybridization capture with analysis of up to 406 cancer-related genes. Human papillomavirus (HPV) sequences were detected by de novo assembly of nonhuman sequencing reads and aligned to the RefSeq database. Immunohistochemistry for programmed death-ligand 1 (PD-L1) was assessed.

RESULTS

One hundred two of 280 vSCCs (36%) contained hrHPV sequences, predominantly HPV 16 (88%). The HPV-positive (HPV+) group was significantly younger (median age, 59 v 64 years; P = .001). Compared with HPV-negative (HPV–) vSCCs, HPV+ tumors showed more frequent pathogenic alterations in PIK3CA (31% v 16%; P = .004), PTEN (14% v 2%; P < .0001), EP300 (14% v 1%; P < .0001), STK11 (14% v 1%; P < .0001), AR (5% v 0%; P = .006), and FBXW7 (10% v 3%; P = .03). In contrast, HPV– vSCCs showed more alterations in TP53 (83% v 6%; P < .0001), TERTp (71% v 9%; P < .0001), CDKN2A (55% v 2%; P < .0001), CCND1 amplification (22% v 2%; P < .0001), FAT1 (25% v 4%; P < .0001), NOTCH1 (19% v 6%; P = .002), and EGFR amplification (11% v 0%; P < .0001), as well as a higher rate of 9p24.1 (PDL1/PDL2) amplification (5% v 1%) and PD-L1 immunohistochemistry high-positive tumor staining (33% v 9%; P = .04).

CONCLUSION

Comprehensive molecular profiles of vSCC vary considerably with hrHPV status and may inform patient selection into clinical trials. Sixty-one percent of HPV+ vSCCs had a pathogenic alteration in the PI3K/mTOR pathway, whereas HPV– vSCCs showed alterations in TP53, TERTp, CDKN2A, CCND1, and EGFR, and biomarkers associated with responsiveness to immunotherapy.

Genes, pathways and vulvar carcinoma - New insights from next-generation sequencing studies

In this review, we summarize the existing literature on next generation sequencing (NGS) studies in vulvar squamous cell carcinoma (VSCC). A total of 201 VSCC tumor samples were investigated in five studies published between 2017 and 2019. Findings on somatic mutations in human papillomavirus (HPV)-DNA positive (HPV+) and HPV-DNA negative (HPV-) disease were extracted and submitted to pathway and drug candidate analyses. The general genetic findings show cell cycle activity aberrations common to both HPV+ and HPV- VSCC. In silico analyses of somatic mutations detected in NGS studies pointed to PI3K-Akt pathway as the main pathway dysregulated in both HPV+ and HPV- VSCC tumors. In addition, pathways specific for HPV+ VSCC, i.e. AMPK, Prolactin, mTOR and Chemokine pathways as well as pathways unique for HPV- disease, i.e. GnRH, Neurotrophin, Oxytocin, Notch pathways were identified. These observations provide a rationale for incorporating novel specific therapeutic strategies in vulvar cancer. In this review, based on the Drug Gene Interaction database analysis of the NGS data, we listed potential drugs for this disease. The candidates revealed in our analysis provide new therapeutic opportunities in VSCC.

Performance of the pattern-based interpretation of p53 immunohistochemistry as a surrogate for TP53 mutations in vulvar squamous cell carcinoma

Aims

The most commonly mutated gene in vulvar squamous cell carcinoma (VSCC) is TP53 and its prognostic value, particularly in HPV‐independent VSCC, is uncertain. In other tumours, p53 immunohistochemistry (IHC) is an excellent surrogate marker for TP53 mutations. In order to study this in VSCC, we assigned six p53 IHC patterns into two final classes: ‘wild‐type’ or ‘mutant’. We determined the performance and interobserver variability of this pattern‐based p53 IHC approach.

Methods and results

Two experienced gynaecological pathologists scored the predefined p53 IHC patterns of 59 VSCC, independently and blinded for molecular data. Agreement was calculated by Cohen's kappa. All disagreements regarding p53 IHC patterns were resolved by a consensus meeting. After DNA isolation, the presence of pathogenic TP53 variants was determined by next‐generation sequencing (NGS). Sensitivity, specificity and accuracy of p53 IHC as a surrogate marker for TP53 mutation status were calculated. Initial p53 IHC pattern interpretation showed substantial agreement between both observers (k = 0.71, P < 0.001). After consensus, 18 cases (30.5%) were assigned a final p53 IHC class as TP53 wild‐type and 41 cases (69.5%) as mutant. The accuracy between the p53 IHC class and TP53 mutation status, after the consensus meeting, was 96.6%. Moreover, the sensitivity and specificity were high 95.3% [95% confidence interval (CI) = 82.9–99.1% and 100% (95% CI = 75.9–100%)].

Conclusions

Pattern‐based p53 IHC classification is highly reproducible among experienced gynaecological pathologists and accurately reflects TP53 mutations in VSCC. This approach to p53 IHC interpretation offers guidance and provides necessary clarity for resolving the proposed prognostic relevance of final p53 IHC class within HPV‐independent VSCC.

Molecular pathways in vulvar squamous cell carcinoma: implications for target therapeutic strategies

BACKGROUND

Additional prognostic factors and personalized therapeutic alternatives for vulvar squamous cell carcinoma (VSCC), especially for advanced stages with poor prognosis, are urgently needed.

OBJECTIVES

To review and assess literature regarding underlying molecular mechanisms of VSCC target therapeutic and prognostic approaches.

METHODS

We performed a narrative literature review from the inception of the database up to January 2020 limited to English language, organizing knowledge in five main fields: extracellular and intracellular cell cycle deregulation, tumor immune microenvironment, tumor angiogenesis and hormones.

RESULTS

EGFR immunohistochemical overexpression/gene amplification, representing early events in VSCC carcinogenesis, have been correlated with a worse prognosis and led to inclusion of erlotinib in cancer guidelines. p16 expression and HPV positivity are linked to a better prognosis, while p53 overexpression is linked to a worse prognosis; thus, biomarkers could help tailoring conventional treatment and follow-up. The implications of PD-L1 positivity in reference to HPV status and prognosis are still not clear, even though pembrolizumab is part of available systemic therapies. The role of tumor angiogenesis emerges through data on microvessel density, immunohistochemical VEGF staining and evaluation of serum VEGF concentrations. Few data exist on hormonal receptor expression, even though hormonal therapy showed great manageability.

CONCLUSIONS

We suggest adding p16, p53 and HPV status to routine hystopathological examination of vulvar biopsies or surgical specimens. Predictive biomarkers for anti-EGFR and anti-PD-1/PD-L1 drugs are needed. Enough preclinical data supporting anti-angiogenic target therapies in clinical trials are existing. Hormonal receptor expression deserves further investigation.

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.

Current status of therapeutic HPV vaccines

The accumulating successes of immune-based treatments for solid tumors have prompted an explosion of cancer clinical trials testing strategies to elicit tumor-specific immune effector responses, either alone, in combination with immune checkpoint blockade, or with conventional cancer treatment modalities. However, across the board, clinical responses have been achieved in only a limited subset of cancer patients, underscoring a critical need to identify mechanisms and biomarkers of response, as well as mechanisms of resistance to therapy. Cancers caused by human papillomavirus (HPV) are driven by two viral oncoproteins, E6 and E7, both of which are functionally required for cellular transformation, thereby providing non-'self', tumor-specific antigenic targets. Immune responses that are specific for either or both of these oncoproteins can be used to follow the magnitude and kinetics of immune responses to therapeutic interventions. Moreover, identifying neoantigens is not a concern in early-stage disease - since HPV cancers are driven by HPV oncoproteins, the somatic mutational load in early disease is low, particularly in comparison to non-HPV-related squamous cancers arising in the same organ site [1,2]. Cancers caused by HPV are a model clinical setting in which to test principles of immunotherapies, and to discover mechanisms of interactions between tumors and their attendant immune milieu. In this review, we will use examples of insights gained from studies of HPV disease to illustrate major themes of immune-based therapeutic strategies.

Association of Retinoic Acid Receptor β Gene With Onset and Progression of Lichen Sclerosus-Associated Vulvar Squamous Cell Carcinoma

Importance

Molecular alterations in lichen sclerosus-associated vulvar squamous cell carcinoma (LS-VSCC) are largely unknown.

Objective

To determine whether the retinoic acid receptor β (RARβ) tumor-suppressor gene is involved in the onset and/or progression of LS-VSCC.

Design, Setting, and Participants

The case-control study, conducted at University-Hospital of Ferrara, Italy, included 20 LS-VSCC (mean [SD] age, 75 [3] years) and 20 cancer-associated vulvar LS (caVLS; mean [SD] age, 62 [11] years) formalin-fixed embedded tissue specimens, 20 cancer-free vulvar LS (cfVLS), and 20 normal skin fresh specimens from diagnostic biopsies and women surgically treated for nonmalignant skin lesions, respectively. RARβ gene expression and promoter methylation were investigated in LS-VSCC and caVLS adjacent to VSCC specimens, and in cfVLS and normal skin specimens, as controls, by RT-Q real-time polymerase chain reaction (PCR) analysis, and sequencing of PCR-amplified bisulfite-treated DNA. c-Jun expression, an RARβ pathway-related gene, was also investigated.

Main Outcomes and Measures

RARβ expression, correlation with its promoter methylation and c-Jun expression, and association with onset or progression of LS-VSCC.

Results

In LS-VSCC, RARβ messenger RNA was 3.4-, 3.6-, and 4.8-fold lower than in caVLS (P = .001), cfVLS (P = .005), and normal skin (P < .001), respectively. The RARβ mRNA levels were similar in caVLS, cfVLS, and normal skin. The RARβ promoter was hypermethylated in 18 (90%) of 20 LS-VSCC, 11 (55%) of 20 cfVLS, 10 (50%) of 20 caVLS, and 5 (25%) of 20 in the normal skin group. The degree of methylation of RARβ promoter was higher in LS-VSCC, ranging from 5 to 9 (full promoter methylation) CpGs methylated, than in caVLS (P = .02), cfVLS (P = .03), or normal skin (P < .001), which was up to 5 CpGs methylated. Importantly, 0 of 8 LS-VSCC with 5 to 6 CpGs methylated and 5 (63%) of 8 LS-VSCC with 7 to 8 CpGs methylated were from patients with lymph node metastasis at diagnosis, respectively, whereas there were 2 of 2 (100%) LS-VSCC samples with 9 CpG methylated from patients with lymph node metastasis at diagnosis and subsequent recurrence. In LS-VSCC c-Jun mRNA was 4.3-, 1.4-, and 2.6-fold higher than in caVLS (P < .001), cfVLS (P = .001), and normal skin (P < .001), respectively. The expression of c-Jun was similar in caVLS, cfVLS, and normal skin.

Conclusions and Relevance

Hypermethylation-induced RARβ down-expression was associated with LS-VSCC and correlates with the upregulation of c-Jun. The degree of methylation of RARβ promoter increased with the malignancy of LS-VSCC. Therefore, RARβ gene dysregulation may play a role in progression of LS-VSCC, and RARβ promoter methylation status may be used as a prognostic marker in clinical treatment of patients with LS-VSCC.

New Directions in Vulvar Cancer Pathology

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

High-Grade Squamous Intraepithelial Lesion of the Gastroesophageal Junction Secondary to High-Risk Human Papillomavirus

OBJECTIVES

Although the role of human papillomavirus (HPV) in the development of some carcinomas (eg, anogenital and oropharyngeal squamous cell carcinomas) is nondebatable, there is still significant controversy regarding the relationship of HPV and esophageal squamous cell carcinomas (SCCs).

METHODS

All cases were sampled at or near the gastroesophageal junctions in patients with reflux and/or known Barrett esophagus and appear to have been initially sampled "incidentally." Patients were all men, aged 56 to 80 years. None had a known history of other HPV-related disease.

RESULTS

We present four cases of high-grade squamous intraepithelial lesion of the gastroesophageal junction secondary to high-risk HPV that have identical histologic features to similar lesions of the anogenital tract.

CONCLUSIONS

Whether such lesions are at risk for developing into invasive SCC remains unclear.

Differentiated Vulvar Intraepithelial Neoplasia-like and Lichen Sclerosus-like Lesions in HPV-associated Squamous Cell Carcinomas of the Vulva

Most human papillomavirus (HPV)-associated vulvar squamous cell carcinomas (VSCCs) originate from high-grade squamous intraepithelial lesions, also named usual type vulvar intraepithelial neoplasia. However, growing evidence suggests that morphologic studies have limitations in predicting HPV status in vulvar lesions. We aimed to evaluate adjacent intraepithelial lesions in a series of DNA HPV-positive VSCCs, focusing on unusual histologic patterns mimicking differentiated vulvar intraepithelial neoplasia (dVIN) or lichen sclerosus (LS). We identified 326 DNA HPV-positive VSCC with at least 1 cm of skin adjacent to the invasive tumor and analyzed HPV typing, HPV E6*I mRNA, and p16 immunohistochemistry in all cases. A careful histologic evaluation was conducted. A conclusive association with HPV was based on a positive p16 or HPV E6*I mRNA result or both in addition to the HPV DNA, whereas cases negative for both markers were classified as nonconclusively associated with HPV. One hundred twenty-one tumors (37.1%) had normal adjacent skin, 191 (58.6%) had only high-grade squamous intraepithelial lesions, also named usual type vulvar intraepithelial neoplasia, and unusual intraepithelial lesions were identified in 14 (4.3%) tumors. Seven cases showed dVIN-like features, 5 showed adjacent LS-like lesion, and in 2 cases dVIN-like and LS-like lesions were identified simultaneously. Six of them were conclusively associated with HPV (3 dVIN-like, 2 LS-like, 1 with combined dVIN/LS-like features). All 6 tumors were associated with HPV16 and were positive for both p16 and HPV mRNA, and p16 was also positive in the dVIN-like and LS-like lesions. In summary, a small subset of VSCCs conclusively associated with HPV may arise on intraepithelial lesions, mimicking precursors of HPV-independent VSCC.

Lichen Sclerosus: An autoimmunopathogenic and genomic enigma with emerging genetic and immune targets

Lichen sclerosus (LS) is an inflammatory dermatosis with a predilection for anogenital skin. Developing lesions lead to vulvar pain and sexual dysfunction, with a significant loss of structural anatomical architecture, sclerosis, and increased risk of malignancy. Onset may occur at any age in both sexes, but typically affects more females than males, presenting in a bimodal fashion among pre-pubertal children and middle-aged adults. A definitive cure remains elusive as the exact pathogenesis of LS remains unknown. A general review of LS, histologic challenges, along with amounting support for LS as an autoimmune disease with preference for a T_h1 immune response against a genetic background is summarized. In addition to the classically referenced ECM1 (extracellular matrix protein 1), a following discussion of other immune and genetic targets more recently implicated as causative or accelerant agents of disease, particularly miR-155, downstream targets of ECM1, galectin-7, p53, and epigenetic modifications to CDKN2A, are addressed from the viewpoint of their involvement in three different, but interconnected aspects of LS pathology. Collectively, these emerging targets serve not only as inherently potential therapeutic targets for treatment, but may also provide further insight into this debilitating and cryptic disease.

Impact of somatic molecular profiling on clinical trial outcomes in rare epithelial gynecologic cancer patients

OBJECTIVES

Conducting clinical trials in rare malignancies is challenging due to the limited number of patients and differences in biologic behavior. We investigated the feasibility and clinical utility of using genomic profiling for rare gynecologic malignancies.

METHODS

Rare epithelial gynecologic cancer patients were analyzed for somatic variants through an institutional molecular profiling program using the Sequenom MassArray platform or the TruSeq Amplicon Cancer Panel on the MiSeq platform. Clinical trial outcomes by RECIST 1.1, and time on treatment were evaluated.

RESULTS

From March 2012 to November 2015, 767 gynecologic patients were enrolled and 194 (27%) were classified as rare epithelial malignancies. At least one somatic mutation was identified in 72% of patients, most commonly in TP53 (39%), KRAS (28%) and PIK3CA (27%). A total of 14% of patients were treated on genotype-matched trials. There were no significant differences in overall response rate between genotype-matched versus unmatched trials, nor in median time on treatment between genotype trials and the immediate prior systemic standard treatment. Among 13 evaluable Low Grade Serous ovarian cancer patients treated on genotype-matched trials with MEK inhibitor-based targeted combinations, there were four partial responses.

CONCLUSIONS

Somatic molecular profiling is feasible and enables the identification of patients with rare gynecologic cancers who are candidates for genotype-matched clinical trials. Genotype-matched trials, predominantly MEK-based combinations in KRAS and/or NRAS mutant Low Grade Serous ovarian cancer patients, and genotype-unmatched trials, have shown potential clinical activity. Prospective trials with integrated genotyping are warranted to assess the clinical utility of next generation sequencing tests as a standard clinical application in rare malignancies.

Clinical and molecular classification of vulvar squamous pre-cancers

Vulvar intraepithelial neoplasia (VIN) is a precursor to vulvar squamous cell carcinoma and is defined histopathologically by the presence of atypia. VIN has been classified into two types: usual vulvar intraepithelial neoplasia (uVIN), which is also referred to as a vulvar high-grade squamous intra-epithelial lesion (HSIL), and differentiated VIN (dVIN). The former is associated with chronic infection by sub-types of the human papilloma virus (HPV), whereas dVIN is HPV-independent and frequently associated with lichen sclerosus. The distinction is important because dVIN has a greater risk of, and more rapid transit to, vulvar squamous cell carcinoma. Furthermore, dVIN-associated vulvar cancers have an increased risk of recurrence and higher mortality than those arising from HSIL. Molecular characterization of vulvar squamous cell carcinoma precursors using next-generation sequencing is a relatively novel, but rapidly advancing field. This review appraises recent studies that have investigated the risks of progression to vulvar malignancy associated with HSIL and dVIN, the prognosis of HPV-dependent and HPV-independent vulvar squamous cell carcinomas, and conducted next generation sequencing mutation analyses to elucidate the genomic profiles underlying VIN. These studies suggest that HSIL and dVIN are characterized by different underlying molecular alterations that may have important implications for treatment and follow-up of women diagnosed with vulvar squamous cell cancer.

Differentiated Vulvar Intraepithelial Neoplasia: A Brief Review of Clinicopathologic Features

Differentiated-type vulvar intraepithelial neoplasia (dVIN) is a non–human papilloma virus (HPV)-related precursor lesion to vulvar squamous carcinoma. The terminology has only become recognized clinically and histopathologically in recent years despite being described more than 50 years ago. As opposed to the HPV-related VIN (uVIN), dVIN has different features of histomorphology, risk of progression, and molecular pathogenesis. Notably, dVIN commonly develops in a background of chronic inflammatory dermatoses such as lichen sclerosis and lichen simplex chronicus. The recognition of dVIN remains a challenge owing to lack of accurate and reproducible diagnostic criteria. Morphologically, basal layer atypia, dyskeratosis, and elongation and anastomosis of the rete ridges are regarded as very useful diagnostic features. Ancillary tests can be very helpful to establish a definitive diagnosis in some ambiguous cases. In contrast to uVIN, dVIN is more likely to progress to vulvar squamous carcinoma in a shorter period. The goal of this review is to elaborate on the clinicopathologic characteristics and underline the key histologic features that best facilitate the diagnosis of dVIN.

Molecular heterogeneity in human papillomavirus-dependent and -independent vulvar carcinogenesis

Vulvar squamous cell carcinoma (VSCC) and precancerous vulvar intraepithelial neoplasia (VIN) can develop through human papillomavirus (HPV)-dependent and -independent pathways, indicating a heterogeneous disease. Only a minority of VIN progress, but current clinicopathological classifications are insufficient to predict the cancer risk. Here we analyzed copy number alterations (CNA) to assess the molecular heterogeneity of vulvar lesions in relation to HPV and cancer risk. HPV-status and CNA by means of whole-genome next-generation shallow-sequencing were assessed in VSCC and VIN. The latter included VIN of women with associated VSCC (VINVSCC ) and women who did not develop VSCC during follow-up (VINnoVSCC ). HPV-testing resulted in 41 HPV-positive (16 VINVSCC , 14 VINnoVSCC , and 11 VSCC) and 24 HPV-negative (11 VINVSCC and 13 VSCC) lesions. HPV-positive and -negative VSCC showed a partially overlapping pattern of recurrent CNA, including frequent gains of 3q and 8q. In contrast, amplification of 11q13/cyclinD1 was exclusively found in HPV-negative lesions. HPV-negative VINVSCC had less CNA than HPV-negative VSCC (P = .009), but shared chromosome 8 alterations. HPV-positive VINnoVSCC had less CNA than VINVSCC (P = .022). Interestingly, 1pq gain was detected in 81% of HPV-positive VINVSCC and only in 21% of VINnoVSCC (P = .001). In conclusion, HPV-dependent and -independent vulvar carcinogenesis is characterized by distinct CNA patterns at the VIN stage, while more comparable patterns are present at the cancer stage. Cancer risk in VIN seems to be reflected by the extent of CNA, in particular chromosome 1 gain in HPV-positive cases.