GM-CSF treatment in patients with B-chronic lymphocytic leukemia

The effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) on the number of granulocytes in peripheral blood and myeloid cells in the bone marrow were studied in seven patients with chronic lymphocytic leukemia (CLL). The neutrophil count in the peripheral blood rose by a median of 193% (range 142-980%), p = 0.02, and the increase persisted for more than 2 weeks after discontinuation of the treatment. The percentage of myeloid cells in bone marrow increased by 166% (range--57-1800%). In neutropenic CLL patients with recurrent infections GM-CSF treatment may constitute a new treatment modality.