The occurrence of Langerhans cell histiocytosis; (LCH) and malignancy in th
e same patient is rare. When LCH occurs concomitantly with acute leukemia,
distinct temporal patterns often exist; acute myelogenous leukemia (AML) ty
pically succeeds LCH, whereas acute lymphocytic leukemia (ALL) usually prec
edes it. We report a case of LCH developing in a child while in remission f
or ALL. Unique features of the; case include the disseminated nature of the
LCH and the death of the patient from LCH rather than ALL.