Vulvar lichen sclerosus (VLS) is characterized by thinning and depigmentation of the vulvar, perineal, and perianal skin, presenting as white lesions. It can occur at any age but is most common in postmenopausal women and, to a lesser extent, in prepubertal girls. While the use of glucocorticoids is effective in alleviating symptoms, complete cure remains challenging, necessitating lifelong follow-up and management.
Etiology
The exact cause is unknown. Contributing factors may include:
- Autoimmunity: Some patients have elevated autoantibodies and increased IgG levels, and others may have concurrent autoimmune disorders.
- Infection
- Genetics: A family history is observed in certain patients, though no specific gene has been identified.
- Sex Hormone Deficiency: Some patients exhibit low serum levels of dihydrotestosterone and androstenedione.
Pathology
On gross examination, the lesions appear white. Microscopically, findings include thinning of the epidermis, hyperkeratosis, atrophy of the stratum spinosum, and depletion of melanocytes. Epithelial rete ridges become blunted or disappear. The superficial dermis shows edema in the early stages, with collagen band homogenization and fibrosis in later stages, accompanied by a band-like lymphocytic infiltrate. Basal layer cell edema and melanocyte depletion are evident. Inflammatory changes or ulcers may be present in a minority of cases. A small proportion of patients may develop non-HPV-associated vulvar intraepithelial neoplasia (VIN) or even progress to squamous cell carcinoma.
Clinical Presentation
Symptoms
Common symptoms include itching, pain, and a burning sensation in the affected area, with advanced disease potentially impacting sexual activity. Young girls often do not exhibit significant itching and may instead experience discomfort in the vulvar or perianal region during urination or defecation.
Signs
Lesions typically involve the labia majora, labia minora, clitoral hood, posterior commissure, and perianal region, commonly in a symmetrical distribution. Vaginal mucosa involvement is rare. In the early stages, the skin may be red and swollen, with pink, ivory-white, or shiny polygonal papules, which may coalesce into bruised-like plaques. As the disease progresses, vulvar atrophy occurs, with thinning of the labia majora, reduction or loss of the labia minora, clitoral atrophy, whitening, tightening, and decreased elasticity of the skin. Fissures, scaling, and extension to the perineum and perianal area in a butterfly-like pattern are commonly observed. In advanced stages, the skin is thin and crinkled, resembling cigarette paper or parchment, with narrowing of the vaginal introitus. In young girls, hyperkeratosis is less pronounced than in adults, with the skin appearing pearly yellow or as mottled areas interspersed with pigmentation changes. Vulvar and perianal lesions may form a "keyhole" shape or white lesions. Spontaneous resolution of the condition during puberty occurs in a proportion of pediatric patients.
Diagnosis
The diagnosis can be based on medical history, clinical symptoms, and physical examination. A definitive diagnosis relies on histopathological examination, although biopsy is not routinely performed, especially in prepubertal girls. A biopsy is indicated under the following circumstances:
- Persistent ulcers, erosions, or suspicion of neoplastic or malignant lesions.
- Lack of response or worsening of symptoms despite prolonged treatment.
- Concurrent squamous intraepithelial lesions of the cervix or vagina.
In some cases, particularly in early-stage disease or post-treatment lesions, histologic findings may lack specificity. Non-specific pathological changes do not exclude the diagnosis of VLS.
Differential Diagnosis
VLS should be differentiated from chronic simple lichenification, lichen planus, vitiligo, mucosal pemphigoid, contact dermatitis, vulvar intraepithelial neoplasia, and secondary skin conditions associated with diabetes, infections, or autoimmune diseases.
Treatment
While some cases of vulvar lichen sclerosus (VLS) in children may resolve spontaneously by puberty, the majority of patients require timely treatment and long-term management. The goals of treatment are symptom relief, disease progression control, preservation of vulvar function, prevention of scarring and adhesions, avoidance of malignant transformation, and improvement of quality of life. The general principles of treatment include:
- Early intervention when symptoms or disease progression are identified.
- Topical corticosteroids (TCs) are the first-line treatment in addition to general care.
- For patients unresponsive to first-line treatments, second-line therapies or physical treatments may be considered.
- Maintenance therapy and long-term management are essential.
General Care
Recommendations include keeping the affected skin clean and dry, avoiding spicy or allergenic foods, and refraining from using irritating medicated products or soaps on the vulva. Breathable clothing, such as underwear made of natural fibers, is recommended over synthetic fabrics. For patients experiencing severe itching that leads to anxiety or insomnia, sedatives or antihistamines may be prescribed.
Topical Treatment
Corticosteroids
Topical corticosteroids are effective due to their strong anti-inflammatory, anti-allergic, immunosuppressive, anti-proliferative, vasoconstrictive, and anti-mitotic effects. They are often used for patients whose symptoms are not alleviated by general care alone. Topical corticosteroids are the first-line treatment for VLS and are usually divided into two phases: induction of remission and maintenance therapy. Selection of corticosteroid potency should be individualized, based on the severity of the lesions and symptoms. TCs are categorized into three potency levels:
- Low potency: 1% or 2.5% hydrocortisone.
- Moderate potency: 0.1% mometasone furoate, 0.1% hydrocortisone butyrate, 0.1% or 0.025% triamcinolone, 0.5% clobetasone butyrate.
- High potency: 0.05% clobetasol propionate, 0.05% betamethasone dipropionate, 0.5% triamcinolone, 0.3% diflucortolone valerate.
Ointments are the preferred formulation due to their higher efficacy and lower irritation.
For initial treatment, moderate- to high-potency TCs such as 0.05% clobetasol propionate ointment are commonly recommended. The more severe the hyperkeratosis or itching, the higher the potency and frequency of application. Typically, the medication is applied 1–2 times daily for 4 weeks, followed by once daily or every other day for another 4 weeks, and then twice weekly for another 4 weeks, for a total of 3 months.
For maintenance therapy, low- to moderate-potency TCs such as 0.1% mometasone furoate, 0.1% hydrocortisone butyrate, or 1% or 2.5% hydrocortisone are used 1–2 times per week. Efficacy should be assessed monthly during the initial treatment phase and every 3–6 months during maintenance therapy. Adjustments to the regimen may be needed until the condition stabilizes or the lesions resolve. Warm sitz baths before applying topical medications can improve symptom relief and enhance absorption. For patients experiencing irritation from medications, moisturizers or emollients can be applied before TCs.
For postmenopausal women with significant vulvar atrophy, estrogen ointment can also be applied. For prepubertal girls without symptoms or hyperkeratosis, observation without TC use is often warranted. For those with symptoms or hyperkeratosis, low- to moderate-potency TCs are applied for shorter durations. Even after symptom resolution, thickened skin may take a long time to improve or return to a normal appearance.
Calcineurin Inhibitors
For confirmed cases where first-line treatment is ineffective, contraindicated, or poses an increased risk of skin atrophy, calcineurin inhibitors can be recommended. These inhibitors suppress lymphocyte activity, alleviating VLS-associated itching and inflammation, with potential restoration of skin pigmentation in some cases. Commonly used medications include:
- 0.1% tacrolimus ointment (for adults),
- 1% pimecrolimus cream,
- 0.03% tacrolimus ointment (for children aged 2 years and older).
For active lesions, the suggested protocol involves application 1–2 times daily for 4 weeks, followed by tapering to once daily or every other day for another 4 weeks, and finally 1–2 times per week for the final 4 weeks.
Systemic Medication
Acitretin, an aromatic derivative of retinoic acid, is used for severe cases of VLS due to its ability to maintain the normal function and structure of epithelial and mucosal tissues. It is typically administered orally at a dose of 20–30 mg/day. Additionally, a combination of multiple vitamins may be prescribed.
Physical Therapy
Local physical therapies aim to remove aberrant epithelial tissues and disrupt the dermal nerve endings, breaking the cycle of itching and scratching. These therapies are suitable for patients with severe symptoms or those unresponsive to medication. Common methods include:
Fractional Laser Therapy
This creates thermal effects in the skin, leading to tissue vaporization, epidermal exfoliation, increased collagen formation, and improved blood flow. It is minimally invasive, has a short recovery time, and is safe, with no scarring.
Focused Ultrasound Therapy
This utilizes the penetrative and localized properties of ultrasound to target the dermis and subcutaneous tissues without damaging surface tissue. Effects include improved local microcirculation, tissue repair, symptom relief, and enhanced skin elasticity.
Surgical Treatment
Surgical treatment is generally not required. However, it may be considered under the following circumstances:
- Suspected precancerous or cancerous lesions.
- Severe adhesions or scarring that affect urination or sexual function.
In severe cases or when medication fails, superficial vulvectomy may be performed. However, the recurrence rate after surgical excision is high. Pre- and post-operative use of medication or physical therapy can improve lesion outcomes and enhance or maintain surgical efficacy.