Keratoacanthoma and PUVA keratoses in a vitiligo patient following oral psoralen photochemotherapy (PUVA)

Abstract

Systemic PUVA therapy can produce various acute reactions and potential long-term damage including benign and malignant skin tumors. Obviously the risk is related to DNA damage, but PUVA-induced down-regulation of immune responses may play an additional role. Keratoacanthoma is etiologically related to sunlight and immunosuppression. PUVA keratoses are raised warty papules with a broad base and a diameter of several millimeters to 1 centimeter, and they are associated with an increased risk of nonmelanoma skin cancer. We report a case of solitary keratoacanthoma and multiple PUVA keratoses all developing in vitiliginous areas in a patient receiving long-term, high-dose PUVA therapy for generalized vitiligo. A 57-year-old Korean female, who had undergone intermittent systemic PUVA therapy for 11 years, noted multiple asymptomatic, yellowish, hyperkeratotic papules on the dorsa of hands and feet 1 year previously, and a bean-sized raised painful nodule filled with keratin plug on the dorsum of right hand 1 month previously. Skin biopsy confirmed the diagnoses of PUVA keratoses and keratoacanthoma, respectively. PCR-SSCP analysis revealed no mutation of p53 tumor suppressor gene in this case.