Vulval dermatoses — lichen sclerosus with a focal ulcer — structured oral station (12 minutes)

Opening prompt — "How do you frame this woman's presentation?"

Model response — the diagnosis plus the concern: ^[1][4]

• "This is vulvar lichen sclerosus — the porcelain-white atrophic plaques in a figure-of-eight distribution around the vulva and perianal skin, with ecchymoses, labial fusion and clitoral burying, and a spared vaginal mucosa, are the classic presentation."
• "My immediate concern is the focal non-healing ulcer on the right labium minus. In a woman with known or suspected lichen sclerosus, a focal ulcer that is resistant to appropriate topical corticosteroid is vulvar intraepithelial neoplasia or invasive squamous cell carcinoma until biopsy proves otherwise."^[1][3]

Probe 1 — "Describe the diagnostic procedure you would perform."

• "A punch biopsy of the ulcer edge under local anaesthetic. I would take a 4 mm punch from the active edge of the ulcer (not the centre of an erosion), with the deepest tissue from the most abnormal area sent for dermatopathology." ^[1]
• "I would add direct immunofluorescence on a separate sample if an autoimmune blistering disorder such as mucous membrane pemphigoid was in the differential." ^[1][4]
• "The biopsy rule is absolute: biopsy at first presentation, and re-biopsy any focal ulcer, raised or hyperkeratotic plaque, treatment-resistant area, atypical change or new lesion — UPRAN: Ulcer, Plaque, Resistant, Atypical, New."^[1][3]

Probe 2 — "The biopsy confirms lichen sclerosus only, with no neoplasia. Describe the first-line treatment."

• "First-line is an ultrapotent topical corticosteroid ointment — clobetasol propionate 0.05% ointment. I use an ointment rather than a cream for better penetration and fewer preservatives."^[1][2]
• "The induction regimen is once daily for about 4 weeks, then a tapering course over the following weeks (alternate days, then twice weekly) guided by clinical response, with a maintenance regimen of a tapered application (e.g. two to three times weekly) and regular clinical review."^[1][2]
• "If she had a poor response to the corticosteroid or did not tolerate it, my second-line option is a topical calcineurin inhibitor (tacrolimus 0.1% ointment). I would not offer surgery for disease control — recurrence after surgery is invariable. Topical testosterone is no longer recommended."^[1][2]

Probe 3 — "What is her lifetime risk of vulvar squamous cell carcinoma, and what is your surveillance plan?"

• "Her lifetime SCC risk is approximately 4 percent, from the Vieira-Baptista 2022 systematic review of 14,372 women with vulvar lichen sclerosus."^[3]
• "The risk is significantly higher in the first 1-3 years after a biopsy of lichen sclerosus, with advancing age, and in the presence of differentiated VIN; it is significantly reduced by ultrapotent corticosteroid use — which is one of the strongest arguments for treating lichen sclerosus even when symptomatic control alone might not seem to justify it."^[3]
• "My surveillance plan is lifelong 6-12 monthly clinical review with biopsy of any focal change, with the highest vigilance in the first three years and in older women."^[1][3]

Probe 4 — Communication: "How do you explain the diagnosis and the surveillance plan to the woman?"

• "I would say: 'You have a long-term skin condition called lichen sclerosus. The good news is that the right ointment controls the symptoms in over 90 percent of women, and the same ointment lowers your risk of skin cancer. The catch is that the condition does carry a small but real lifetime risk of turning into a skin cancer — about 4 in 100 — so I want to see you every 6 to 12 months for the rest of your life, and you must come back sooner if you notice any new lump, ulcer or sore that doesn't heal. The biopsy of the ulcer today was the right thing to do, and the result is reassuring.'"^[1][3]