Effect of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) on chemotherapy-induced myelosuppression in patients with chronic lymphocytic leukemia: a crossover study

Patients with advanced, refractory chronic lymphocytic leukemia (CLL) have an high morbidity and mortality from infections following chemotherapy-induced myelosuppression. A crossover study on the prophylactic effect of GM-CSF therapy on neutropenia was carried out in 12 patients with advanced CLL. The patients received GM-CSF in association with every second cycle of COP (cyclophosphamide, vincristine, prednisone) chemotherapy. A total of 40 COP cycles were analyzed. Blood neutrophil levels were significantly higher two to three weeks after the first COP cycle followed by GM-CSF (medians 2.24 and 5.47 x 10(9)/l) when compared to the first cycle without GM-CSF support (0.59 and 0.75 x 10(9)/l; p < 0.0195 and <0.002, respectively). In the next two cycles the same tendency persisted, although the difference was not statistically significant. There were no significant differences in the number of febrile days, days on intravenous antibiotics, hospitalization days, or the number of red blood cell transfusions. Mortality during COP treatment was 8%. In conclusion, GM-CSF efficiently ameliorates chemotherapy-induced neutropenia in CLL patients with a poor bone marrow reserve due to advanced disease.