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. The condition frequently is misdiagnosed as atypical lymphoma. Generally, the diagnosis is made retrospectively, after the leukemic cells appear in peripheral blood or bone marrow samples. Immunohistochemical studies are the primary methods for diagnosis. Prognosis is usually poor. We describe the case of a 75-year-old woman with acute aleukemic monocytic leukemia cutis who developed systemic disease 1 1/2 years after skin involvement.