TRANSFORMATION OF CONGENITAL NEUTROPENIA INTO MONOSOMY-7 AND ACUTE NONLYMPHOBLASTIC LEUKEMIA IN A CHILD TREATED WITH GRANULOCYTE-COLONY-STIMULATING FACTOR

A cytogenetically normal infant with Kostmann syndrome (severe congeni tal granulocytopenia) was treated with granulocyte colony-stimulating factor, which resulted in a rapid improvement in his neutrophil count and a resolution of recurrent infections, After 11 months of therapy, splenomegaly developed, with thrombocytopenia, anemia, circulating nuc leated erythrocytes, and acquired monosomy 7, which evolved during a p eriod of 7 months into acute nonlymphoblastic leukemia, The use of gra nulocyte colony-stimulating factor in patients with congenital marrow failure disorders may induce or hasten the onset of a malignant transf ormation.