Hypertrophic lichen planus mimicking squamous cell carcinoma

An 87-year-old female presented with a 3 month history of hyperkeratotic nodules on her left shin. An initial clinical and histological diagnosis of multiple squamous cell carcinomas on the left shin was made. Review of the biopsy, however, showed hypertrophic lichen planus with pseudoepitheliomatous hyperplasia. Typical lichen planus was seen affecting the oral mucosa, nails and skin elsewhere.