Aleukemic Monocytic Leukemia Cutis

Aleukemic leukemia cutis is a rare condition in which leukemic cells invade the skin before they appear in peripheral blood or bone marrow specimens. Herein we describe a 67-year-old man who underwent assessment because of papules and nodules on his back and lower extremities. A biopsy of these lesions confirmed a dense, predominantly monocytic infiltrate of the dermis and subcutaneous tissue. Immunohistochemical stains were positive for CD43 (Leu-22) as well as monocytic markers. Bone marrow and peripheral blood examinations failed to reveal leukemia. Treatment was based on the results of the skin biopsy, and the patient is doing weill year after therapy.