Clinical overview
Lichen sclerosus (LS) is a chronic, inflammatory, lymphocyte-mediated dermatosis with predilection for the anogenital region of women, particularly postmenopausal women but also prepubertal girls. It is the single most common cause of severe vulval itch in the older woman, the most under-diagnosed cause of postcoital bleeding, dyspareunia, and labial scarring, and — critically — carries a 4–5% lifetime risk of progression to differentiated vulval intraepithelial neoplasia (dVIN) and subsequent vulval squamous cell carcinoma. Every clinician examining a vulva should be able to recognise it, treat it adequately, and arrange long-term surveillance.
The chapter is a description of the pathology and how that pathology produces the clinical features. Management is summarised but the surveillance and malignant-potential elements are emphasised.
Core knowledge
Aetiology and pathogenesis
Multifactorial. Current model:
- Autoimmune basis — increased prevalence of other autoimmune diseases (thyroid disease, vitiligo, alopecia areata, pernicious anaemia). T-cell mediated damage to basal keratinocytes and basement membrane. Circulating autoantibodies (e.g., to extracellular matrix protein 1, ECM-1) in many patients.
- Genetic susceptibility — HLA associations (HLA-DQ7).
- Hormonal — typically a postmenopausal hypoestrogenic environment, although LS occurs in prepubertal girls and rarely in reproductive-age women.
- Local trauma — Koebnerisation (lesions developing at sites of injury, friction, scratching, episiotomy scar).
- Infection — Borrelia link investigated and discounted in most populations.
Histopathology (the diagnostic appearance)
The diagnostic biopsy pattern stacks hyperkeratosis, a flattened epidermis, hyalinised dermis, and lymphocytes.
Three classic layers visible on biopsy of a developed lesion:
- Hyperkeratosis with follicular plugging — thickened keratin at the surface.
- Atrophic epidermis with loss of rete ridges — epidermis is thinned and flattened.
- Subepidermal hyalinisation — a homogeneous, pale, eosinophilic band in the upper dermis ("pink zone").
- Lymphocytic infiltrate beneath the hyalinised band.
Early lesions may only show the lymphocytic infiltrate without the hyalinisation; biopsy timing matters. In long-standing disease, the architecture is so distorted that biopsy may yield only fibrotic tissue, but the diagnosis is then clinically obvious.
Clinical features explained by the pathology
- Pallor — atrophic epidermis, loss of melanocyte function, dermal hyalinisation.
- Skin fragility, fissuring — thinned epidermis, loss of normal elasticity.
- Itch — chronic inflammation; one of the most severe pruritic dermatoses, often with disturbed sleep.
- Pain, burning, dyspareunia — fissuring, atrophy, mucosal involvement.
- Loss of vulval architecture — over time, the labia minora may resorb into the labia majora; the clitoral hood phimoses; the introitus narrows (with or without true stenosis). This scarring is irreversible.
- Ecchymoses and "purpura" — fragile dermis bleeds easily; haemorrhagic blisters can occur.
- Distribution — classic "figure-of-eight" or "keyhole" pattern around the vulva and perianal area, but spares the vagina (a defining feature; if vaginal mucosa is involved, consider lichen planus instead).
- Extragenital LS — affects ~15% of patients; trunk, neck, axillae, wrists; not pre-malignant when extragenital.
Demographics and presentation patterns
- Postmenopausal women — the dominant group. Vulval itch becoming chronic; sometimes years of self-treatment with antifungals before correct diagnosis.
- Prepubertal girls — second peak. Often misdiagnosed as candidiasis, threadworms, or sexual abuse (because of erythema, purpura, and discomfort). Most cases improve at puberty but may persist.
- Reproductive-age women — least common but increasingly recognised.
Malignant potential
- ~4–5% lifetime risk of squamous cell carcinoma of the vulva in untreated or poorly controlled LS.
- The pathway is via differentiated VIN (dVIN) — HPV-independent, p53-positive, often subtle clinically (small thickened plaque), aggressive natural history.
- Risk reduction with adequate topical steroid use and ongoing surveillance is well established (long-term studies show very low cancer rates in well-treated patients with sustained mucocutaneous remission).
- See vulval-carcinoma for diagnostic and management implications.
Assessment
History
- Itch (severity, sleep disturbance), pain, burning, dyspareunia.
- Bleeding (purpuric, postcoital).
- Onset, duration; relationship to menopause or oestrogen status.
- Effect on quality of life (sexual function, sleep, mood).
- Previous treatments and their effects.
- Autoimmune history (thyroid disease, vitiligo, T1DM).
- Family history (small genetic component).
Examination
- Inspect with good lighting.
- Document distribution (label diagram): figure-of-eight, keyhole, perianal involvement.
- Look for white sclerotic plaques, atrophic skin, ecchymoses, fissures, architectural change (labial resorption, clitoral phimosis, introital narrowing).
- Vagina is spared (distinguishes from lichen planus).
- Palpate for thickened or ulcerated areas — biopsy any to exclude dVIN/SCC.
Investigations
- Biopsy — confirms diagnosis in atypical or refractory disease, and mandatory for:
- Any area not responding to potent topical steroid after 3 months.
- Any thickened plaque, ulcer, persistent erosion, or pigmented area (rule out dVIN, melanoma, SCC).
- Atypical clinical presentation.
- Routine baseline biopsy at diagnosis is debated; many centres do biopsy at first dermatology / vulval clinic visit.
- Thyroid function, autoimmune screen if clinically indicated.
Management
Topical steroids — the mainstay
The single most important intervention. Untreated LS causes progressive scarring and elevates SCC risk; well-treated LS is essentially cured of symptoms and malignant risk falls toward population baseline.
Induction regimen (BSSVD / BAD 2018):
- Clobetasol propionate 0.05% ointment.
- Once daily nocte for 4 weeks → alternate days for 4 weeks → twice weekly for 4 weeks.
- Total of ~30 g (one tube) should last 12 weeks.
Maintenance:
- Twice weekly clobetasol indefinitely (or step down to a less potent steroid for some patients).
- Lifelong management; LS does not "burn out."
- Patient education about correct application: a small amount (fingertip unit), rubbed in until absorbed, to affected areas only.
Other topicals
- Tacrolimus 0.1% ointment — second line for steroid-sparing in selected cases; less effective than clobetasol; small theoretical concern about long-term immunomodulation and cancer risk (data reassuring overall).
- Emollients — daily; restore barrier function; reduce flares.
- Topical oestrogens — for coexisting atrophic vaginitis (LS does not extend into vagina, but the introitus may benefit).
Skin care
- Avoid soap; use emollients as soap substitute.
- Avoid scented products, wipes, tight underwear.
- Pure cotton underwear.
- Sitz baths for soothing.
Surgery
- Reserved for: introital stenosis causing dyspareunia (vestibulectomy + vaginal advancement flap or perineoplasty); urethral or anal stricture; suspected or confirmed SCC.
- Do not perform "cosmetic" surgery — disease will recur in the surgical field.
Surveillance
- Long-term — 6-monthly review until controlled, then 6–12 monthly.
- Photograph annually to document any change.
- Examine for new thickening, ulceration, leukoplakia, pigmented area, asymmetric lesion → biopsy promptly.
- Lifelong follow-up because of dVIN/SCC risk.
Special situations
- Prepubertal girls: similar treatment with clobetasol; usually shorter course; safeguarding screen if any concern of sexual abuse (LS purpura and ecchymoses can mimic trauma — clinical and histological diagnosis differentiates).
- Pregnancy: clobetasol is safe in pregnancy (category C; minimal systemic absorption from topical use; benefits clearly outweigh risks).
- HIV-positive: standard management; consider lower threshold for biopsy of unusual lesions.
Counselling
- Lifelong condition; well controlled, not "cured" by treatment.
- Need for indefinite maintenance treatment.
- Recognition of warning signs (new thickening, ulcers).
- Sexual function — vaginal trainers and lubricants; pelvic floor physiotherapy where indicated.
- Psychological impact often significant; offer support.
Red flags / pitfalls
- Diagnosing "candidiasis" repeatedly in a woman who actually has LS — biopsy if persistent itch.
- Inadequate steroid potency or duration — clobetasol is the right choice; under-treatment is the rule.
- Stopping treatment when symptoms resolve — relapse common; needs maintenance.
- Missing dVIN — biopsy any persistent or new thickened lesion.
- Vaginal involvement — reconsider diagnosis; think lichen planus.
- Failing surveillance — SCC risk is real.
- Confusing prepubertal LS with sexual abuse — clinical features and histology distinguish; safeguarding still considered systematically.
- Cosmetic surgery in LS — disease recurs.
Evidence anchors
- British Association of Dermatologists (BAD) guidelines for the management of lichen sclerosus (Lewis FM et al., Br J Dermatol 2018) — primary management reference.
- British Society for the Study of Vulval Disease (BSSVD) patient information and clinician guidelines.
- ISSVD 2015 Terminology — anatomical and lesion terminology.
- RCOG GTG 58 (Vulval Skin Disorders, archived 2024+) — superseded by BAD/BSSVD documents.
- WHO Classification of Female Genital Tumours, 5th edition — dVIN/SCC classification.
- NICE NG12 — Suspected cancer: recognition and referral — vulval lesion 2-week-wait criteria.
- South African EML / National Department of Health Standard Treatment Guidelines — clobetasol availability (Level 2/3 facilities).
- Lee A, et al. Long-term management of adult vulvar lichen sclerosus: a prospective cohort study of 507 women. JAMA Dermatol 2015 — landmark study on outcomes with adequate steroid use.