Squamous carcinoma following lichen planus of the vulva.

A 58-year-old woman presented with typical cutaneous features of lichen planus (LP). She had suffered from vulval pruritus for 3 years, and examination showed lesions suggestive of LP on the vulva. Three months later a plaque developed on the clitoral hood, and biopsy showed an invasive squamous carcinoma. After vulvectomy, features of LP were found in the excised specimen. Vulval LP should be carefully monitored for possible malignant transformation.