A case of irritated seborrheic keratosis associated with a previous incision site.

An 83-year-old woman had undergone an external dacryocystorhinostomy with silicone intubation. Before the surgery, no skin lesions were observed on the incision site. Three months after surgery, the patient complained of a brown-to-black pigmented elevation at her previous skin incision site. A punch biopsy of the pigmented mass was performed. The histopathologic findings confirmed the clinical diagnosis of irritated seborrheic keratosis (SK). SK can occur several months postoperatively and can suddenly increase in size, so surgeons need to carefully check patients' skin prior to surgery. To our knowledge, this is the first reported case of irritated SK discovered on a previous skin incision site.