Combination therapy with granulocyte colony-stimulating factor, all-trans retinoic acid, and low-dose cytotoxic drugs for acute myelogenous leukemia.

A 67-year-old man presented with acute myelogenous leukemia (M2). Peripheral blood examination revealed a leukocyte count of 1,700/mu l with 1% myeloblasts, and bone marrow aspiration showed 42.6% myeloblasts with Auer bodies. Culture of his marrow cells at diagnosis showed that granulocyte colony-stimulating factor (G-CSF) promoted cell proliferation, while all-trans retinoic acid (ATRA) inhibited the proliferative effect of G-CSF and induced differentiation. Combination therapy with G-CSF, ATRA, and low-dose cytotoxic drugs achieved complete remission without severe marrow suppression.