ACUTE MONOBLASTIC LEUKEMIA WITH SKIN NODULES IN AN ADULT

An 18-year-old man had a 3-week history of malaise, a 1-week history o f a papular eruption, and increasingly severe multisystem neurologic s ymptoms. A diagnosis of acute monoblastic leukemia was made. Immunophe notypic characterization of peripheral blood, bone marrow, and cutaneo us infiltrates revealed a predominant myelomonocytic phenotype with th e coexpression of intercellular adhesion molecule type 1, IgE receptor , terminal deoxynucleotidyl transferase, and some T-cell markers. Thes e findings may have important clinical and pathogenetic implications r egarding the biologic and pathologic behavior of the myelomonocytic le ukemic cells. They also explain in part the impressive presentation of the disease in the skin.