A case of lymphomatoid keratosis.

Lymphomatoid keratosis (LK) is considered to be a rare variant of cutaneous lymphoid hyperplasia, with epidermotropism. We herein report a case of LK which developed on the abdomen of an elderly Korean woman. A 60-year-old woman presented with a 10-year history of a pruritic, solitary, brown to black plaque on the abdomen. Histopathologically, the specimen showed hyperkeratosis, parakeratosis, acanthosis and Pautrier's micro-abscess in the epidermis, and a lichenoid infiltration of lymphocytes in the dermis, which expressed both B cell and T cell lineage on the immune-histochemical staining. Based on these clinical and histopathological findings, our case was diagnosed as LK. To our knowledge, this is the first case report of LK in the Korean dermatologic literature.