The possible role of human papillomavirus infection in the development of lichen sclerosus

Advances in the pathogenesis of vulvar lichen sclerosus

Vulvar lichen sclerosus (VLS) is a chronic non-neoplastic skin lesion characterized by vulvar itching, pain, atrophy, whitening of the skin and mucous membranes, and gradual atrophy and disappearance of the labia minora, which can eventually lead to vulvar scarring, causing functional impairment and seriously affecting the patient's physical and mental health. VLS can occur at any age, however, its pathogenesis and etiology are not fully understood. Considerable progress has been made in related research on genetic susceptibility factors, autoimmune disorders, collagen metabolism abnormalities, and their triggering factors in disease formation and progression. This article reviews the etiology of vulvar lichen sclerosus.

The vulvar microbiome in lichen sclerosus and high-grade intraepithelial lesions

Background

The role of the vulvar microbiome in the development of (pre)malignant vulvar disease is scarcely investigated. The aim of this exploratory study was to analyze vulvar microbiome composition in lichen sclerosus (LS) and vulvar high-grade squamous intraepithelial lesions (HSIL) compared to healthy controls.

Methods

Women with vulvar lichen sclerosus (n = 10), HSIL (n = 5) and healthy controls (n = 10) were included. Swabs were collected from the vulva, vagina and anal region for microbiome characterization by metagenomic shotgun sequencing. Both lesional and non-lesional sites were examined. Biophysical assessments included trans-epidermal water loss for evaluation of the vulvar skin barrier function and vulvar and vaginal pH measurements.

Results

Healthy vulvar skin resembled vaginal, anal and skin-like microbiome composition, including the genera Prevotella, Lactobacillus, Gardnerella, Staphylococcus, Cutibacterium, and Corynebacterium. Significant differences were observed in diversity between vulvar skin of healthy controls and LS patients. Compared to the healthy vulvar skin, vulvar microbiome composition of both LS and vulvar HSIL patients was characterized by significantly higher proportions of, respectively, Papillomaviridae (p = 0.045) and Alphapapillomavirus (p = 0.002). In contrast, the Prevotella genus (p = 0.031) and Bacteroidales orders (p = 0.038) were significantly less abundant in LS, as was the Actinobacteria class (p = 0.040) in vulvar HSIL. While bacteria and viruses were most abundant, fungal and archaeal taxa were scarcely observed. Trans-epidermal water loss was higher in vulvar HSIL compared to healthy vulvar skin (p = 0.043).

Conclusion

This study is the first to examine the vulvar microbiome through metagenomic shotgun sequencing in LS and HSIL patients. Diseased vulvar skin presents a distinct signature compared to healthy vulvar skin with respect to bacterial and viral fractions of the microbiome. Key findings include the presence of papillomaviruses in LS as well as in vulvar HSIL, although LS is generally considered an HPV-independent risk factor for vulvar dysplasia. This exploratory study provides clues to the etiology of vulvar premalignancies and may act as a steppingstone for expanding the knowledge on potential drivers of disease progression.

Comorbidities in Male Patients With Lichen Sclerosus: A Case-Control Study

OBJECTIVE

Lichen sclerosus (LS) is a chronic inflammatory skin disease. In male patients, it usually involves the glans penis and foreskin and can cause phimosis or meatal stenosis. The aim of this cross-sectional case-control study was to identify clinically important comorbidities in male patients with LS.

MATERIALS AND METHODS

By searching Turku University Hospital electronic health records, the authors identified 630 male patients diagnosed with LS between 2004 and 2020. To investigate possible comorbidities, the authors compared this patient group to a 10-fold larger control group.

RESULTS

The incidence of LS increased during the study period, from 5 to 27.5 per 100,000 men. Patients were most often diagnosed at 21 to 25 years of age. Patients with LS exhibited markedly increased risks of penile carcinoma (odds ratio [OR], 81.0; 95% CI = 10.82-3516.7; p < .001) and carcinoma in situ of the penis (OR = 60.5; 95% CI = 7.32-2738.9; p < .001). Patients also more commonly exhibited lichen planus (OR = 16.8; 95% CI = 8.97-32.39; p < .001), psoriasis (OR = 3.3; 95% CI = 1.80-5.70; p = .004), angina pectoris (OR = 1.8; 95% CI = 1.10-2.81; p = .013), obesity (OR = 2.6; 95% CI = 1.72-3.77; p < .001), type 2 diabetes (OR = 2.3; 95% CI = 1.74-3.09; p < .001), and hypertension (OR = 1.9; 95% CI = 1.53-2.37; p < .001). The most commonly performed urological procedures were operation for phimosis, uroflowmetry, and ultrasound measurement of residual urine.

CONCLUSIONS

Genital malignancies, other dermatological conditions, and diseases related to metabolic syndrome should be considered when treating patients with LS.

Alpha, Beta, and Gamma Human Papillomaviruses in Genital Lichen Sclerosus: A Retrospective Cross-Sectional Study

BACKGROUND

Lichen sclerosus (LS) is an inflammatory disease mostly arising at the genital level. It is unclear whether human papillomaviruses (HPVs) have an etiological significance in LS, and data on their prevalence in patients with LS are controversial.

OBJECTIVES

The authors assessed alpha, beta, and gamma HPV prevalence in patients with genital LS. The association of HPV positivity with demographic and clinical factors was also investigated.

METHODS

One hundred thirty-two formalin-fixed, paraffin-embedded LS samples (2016-2020) were retrieved from the archives of a pathology department. Alpha HPVs were genotyped with the INNO-LiPA HPV Genotyping Extra II kit. Beta and gamma HPVs were searched by multiplex Polymerase Chain Reaction. Immunostaining for p16 INK4a was performed on high-risk HPV-positive samples.

RESULTS

Patients had a median age of 61 years, were mostly women ( n = 73, 55.3%), and with an early disease stage ( n = 79, 59.8%). Alpha HPVs were detected in 12/132 cases (9.1%). Among the 5 high-risk HPV-positive cases, only 2 displayed a strong and diffuse p16 INK4a staining. Beta genus was the most prevalent (35/132, 26.5%) and HPV5 was the most frequent beta genotype (25/132, 18.9%). There were 3 gamma HPV-positive cases among those with a valid result (3/131, 2.3%). Multiple infections with genotypes belonging to different genera were infrequent (3/131, 2.3%). No significant differences in the prevalence of the individual genera were observed according to sex and disease stage.

CONCLUSIONS

Of the 3 HPV genera, beta genus showed the highest prevalence. Further research is needed to clarify whether the presence of beta HPVs in genital LS has a clinical significance.

Comorbidity of Urogynecological and Gastrointestinal Disorders in Female Patients With Lichen Sclerosus

OBJECTIVE

Lichen sclerosus (LS) is a chronic inflammatory disease with a significant impact on quality of life. The aim of this cross-sectional case-control study was to characterize concomitant urogynecological and gastrointestinal disorders in female patients with LS.

METHODS

A medical records search between 2004 and 2012 yielded 455 women and girls (mean age 64 years) with LS. The study cohort was compared with a 10-fold age- and sex-matched control cohort. Gynecological cancers and their precursors; gynecological, urinary, and gastrointestinal disorders; and pain syndromes were evaluated.

RESULTS

The well-known association between LS and increased risk of vulvar cancer and its precursors was also found in our study (relative risk [RR] = 100.0; p < .001 and high-grade squamous intraepithelial lesions RR = 110.0; p < .001, respectively), but we also found an increased risk for cervical cancer (RR = 6.0; p = .005) and endometrial cancer (RR = 2.9; p < .001). Gynecological pain syndromes such as dyspareunia (RR = 20.0; p < .001) and interstitial cystitis (RR = 5.0; p < .001) and urinary incontinence (RR = 4.8; p < .001) were also increased. Among gastrointestinal disorders, we found increased risk for celiac disease (RR = 6.8; p < .001), diverticular intestine diseases (RR = 1.9; p < .001), functional intestinal disorders (RR = 2.3; p = .003), and anal and rectal fissures (RR = 2.4; p = .046).

CONCLUSIONS

We found that female patients with LS have an increased risk for gynecological cancers as well as for several urogynecological and gastrointestinal disorders. Increased awareness is required to identify and treat these concomitant disorders.

Lichen sclerosus: A C5B-9 mediated chronic microvascular injury syndrome potentially reflective of common adult comorbidities

Lichen sclerosus (LS) is a cutaneous disease of unknown etiology that often involves the vulva or foreskin but also can affect extragenital sites. Regardless of the anatomic site, the histomorphology and presumably pathogenesis are similar. Perhaps a clue to the pathophysiology of LS lies in its frequent association with morphea, specifically, when occurring in an extragenital context. In our experience a striking feature evident in established lichen sclerosis (LS) is one of superficial vascular drop out whereby residual vessels exhibited endothelial cell necrosis and microvascular basement membrane zone thickening, the latter reflective of antecedent episodes of microvascular injury. We sought to understand the pathophysiology that underlies the distinct vascular changes and in doing so, shed light on the pathogenesis of LS. We examined 44 cases of LS over a period of 2019 to 2021. We were able to obtain past medical histories in 34 of the 44 cases. Regarding pathological assessment, the predominant focus was on microvascular changes. We assessed the role of C5b-9 mediated vascular injury in the pathogenesis of the vasculopathy and enhanced type I interferon signaling in vessels given the morphologic semblance to the select interferonopathy syndromes, namely fibrosing dermatomyositis and Kohlmeier Degos disease. We examined the expression of CMV DNA and protein based on prior observations in an earlier study that isolated early protein expression in the microvasculature in the setting of LS and scleroderma. From a clinical perspective, the most striking association was an older age at the time of diagnosis (mean age of 62 years and median age of 61.5 years) and the presence of vascular comorbidities of diabetes, hypertension, and hyperlipidemia in almost 80% of cases. All cases showed significant microvascular changes in the superficial corium with the most frequent findings being those of significant basement membrane zone reduplication and vascular drop out. A number of cases showed prominent microvascular deposits of C5b-9 in the zone of hyalinizing fibrosis or subjacent to the discernible table of fibroplasia in the absence of enhanced type I interferon signaling. In no case were there viral cytopathic changes associated with CMV affecting the endothelium. The studies that encode CMV DNA or protein did not show a significant role for CMV reactivation in endothelium in the majority of the studied cases. It is concluded that the pathophysiology of LS includes a microvascular injury syndrome within the papillary dermis. The mechanism of endothelial cell injury is complement mediated at least in part and could reflect an adaptive immune response targeting endothelium indicative of classic complement pathway activation when coexisting with morphea or occurring in younger individuals. A non-immune based endothelial dysfunction and complement mediated injury unrelated to antibody driven classic complement pathway activation are more likely pathogenetically in the setting of certain diseases like diabetes mellitus and hypertension. Vascular drop out can be explained by the diminished endothelial progenitor pool needed to repopulate the damaged microvessels in certain settings like hypertension and diabetes.

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.

HPV-Positive and HPV-Negative Vulvar Squamous Cell Carcinoma Are Biologically, but Not Clinically, Distinct

Vulvar squamous cell carcinoma (VSCC) pathogenesis is traditionally defined by the presence or absence of human papillomavirus (HPV), but the definition of these groups and their molecular characteristics remains ambiguous across studies. Here, we present a retrospective cohort analysis of 36 patients with invasive VSCC where HPV status was determined using RNA in situ hybridization (ISH) and polymerase chain reaction (PCR). Clinical annotation, p16 immunohistochemistry (IHC), programmed death ligand-1 (PD-L1) IHC, HPV16 circular E7 RNA (circE7) detection, and RNA-sequencing (RNA-seq) of the cases was performed. A combination of ISH and PCR identified 20 cases (55.6%) as HPV-positive. HPV-status did not impact overall survival (HR: 1.36, 95% CI: 0.307 to 6.037, p=0.6857) or progression-free survival (HR: 1.12, 95% CI: 0.388 to 3.22, p=0.8367), and no significant clinical differences were found between the groups. PD-L1 expression did not correlate with HPV status, but increased expression of PD-L1 correlated with worse overall survival. Transcriptomic analyses (n=23) revealed distinct groups, defined by HPV status, with multiple differentially expressed genes previously implicated in HPV-induced cancers. HPV-positive tumors showed higher global expression of endogenous circular RNAs (circRNAs), including several circRNAs that have previously been implicated in the pathogenesis of other cancers.

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.

Immunogenetics and human papillomavirus (HPV) in male genital lichen sclerosus (MGLSc)

BackgroundThe pathogenesis of male genital lichen sclerosus (MGLSc) is controversial. Incriminated factors include infection with human papillomavirus (HPV) and autoimmunity (e.g. Human Leukocyte Antigen [HLA]). To address the roles of HLA and HPV in MGLSc we studied adult Caucasian males with a clinical and histological diagnosis of MGLSc. The men in the study attended two specialised Male Genital Dermatoses Clinics between July 2011 and September 2012 and were selected and phenotyped from the clinical records. DNA was extracted from blood and paraffin-embedded biopsy sections, for HLA and HPV typing, respectively. HLA allele frequencies were compared with those derived from the UK-based Caucasian population. Eighty-eight cases of MGLSc were identified. HPV DNA was detected in 33/88 (37.5%) cases of MGLSc. HPV16 was the most prevalent type found: 11/88 (12.5%) MGLSc. No statistically significant HLA associations were established but HLA-B*35, -B*51, -C*15, -DRB1*04, -DRB1*10 (predisposition) and -DQA1*01 (protection) were revealed as alleles of interest. HPV16-associated MGLSc cases showed no statistically significant association with HLA genotype. The relationship between HPV and MGLSc suggests a passenger effect rather than a pathogenic role. HLA is not associated with MGLSc nor co-existent HPV16.

Recent advances in understanding and managing Lichen Sclerosus

Lichen sclerosus (LS), or balanitis xerotica obliterans as it was previously known, is a chronic inflammatory lymphocyte-mediated scarring dermatosis that often affects the preputial skin and glans, leading to phimosis and urethral strictures if left untreated. We present a narrative review of the literature assessing its aetiology and pathogenesis and discuss its links to penile cancer and its medical and surgical management. Possible hypotheses for the development of LS include chronic exposure to trapped urine, leading to changes in the epithelial structure. This is supported by the fact that circumcision is often curative in the early stages of the disease. Although circumcision can be curative, the use of topical steroids is typically the first-line treatment and may preserve the foreskin and forgo the need for circumcision altogether. Patients should be made aware of a possible association with penile cancer. Although the majority of cases can be treated by medical therapy and circumcision, a significant number of patients may also require penile reconstructive procedures.

Balanitis xerotica obliterans: a review of diagnosis and management

Balanitis xerotica obliterans (BXO), or penile lichen sclerosus, is a progressive sclerosing inflammatory dermatosis of the glans penis and foreskin. It is associated with significant morbidity and may result in impaired urinary and sexual function. It was initially described by Stuhmer in 1928, named after its pathological features, and is considered the male equivalent of vulvar lichen sclerosis (LS).^3,40 The etiology of BXO is uncertain; however, autoimmune disease, local trauma, and genetic and infective causes have been proposed. BXO occurs most commonly on the prepuce and glans penis. It is considered to have premalignant potential to transform into squamous neoplasia. This postulation rests on retrospective studies and parallels drawn with vulvar LS and squamous cell carcinoma (SCC) development. Histologically, BXO and vulvar LS are considered the same disease.⁴¹ There is a paucity of evidence-based guidelines to assist with appropriate follow-up for patients with BXO.

[Lichen sclerosus : Symptoms, diagnosis, therapeutic procedures]

Lichen sclerosus is a chronic, inflammatory dermatosis that usually affects the anogenital area. Early diagnosis and subsequent long-term anti-inflammatory treatment may reduce symptoms and signs and the risk of a mutilating course and the development of carcinomas.