The effect of GM-CSF on reticulocytes, haemoglobin and haematocrit in patients receiving chemotherapy for solid...

The effect of granulocyte-macrophage colony stimulating factor (GM-CSF) on reticulocytes, haemoglobin and haematocrit levels of patients receiving chemotherapy for solid tumours was assessed. Forty-two patients were randomized into two groups who either did or did not receive GM-CSF 300 U/d on days 8 and 15 post-chemotherapy for neutropenia prophylaxis. Patients were stratified according to tumour type (non small-cell lung cancer, small-cell lung cancer, ovarian and breast cancer). Eight patients with progressive disease were excluded. The 34 patients evaluated completed six chemotherapeutic cycles of 21 days. They did not receive transfusions or erythropoietin. The estimated dose intensities (mg/m2/d) for each drug used were significantly higher in the group on GM-CSF compared to the group without. Haemoglobin and haematocrit were measured by the H * 1 (Bayer) haematology analyser and reticulocyte counts by the flow-cytometric reticulocyte analyser, R-1000 (Sysmex). Measurements were conducted on days 1 and 12 of every cycle for six cycles. At the beginning of therapy there were no significant differences between the two groups. However, red cell and reticulocyte counts fell significantly in the group without GM-CSF compared to the group on GM-CSF. Reticulocyte differences preceded those of haemoglobin and haematocrit. The data indicate a positive in vivo effect of GM-CSF on the erythroid tissue of patients receiving chemotherapy for solid tumours.