Serum concentrations of G-CSF during high-dose chemotherapy with autologous stem cell rescue

In 20 patients treated for refractory germ cell tumors, endogenous G-CSF levels were monitored before and after high-dose chemotherapy with autologous stem cell rescue (ASCR). An inverse relationship was found between endogenous G-CSF levels and peripheral blood leucocyte counts. G-CSF levels were not detectable prior to ASCR, but increased to a maximum of 3400 pg/ml (range 120-15000 pg/ml) thereafter. There was no relationship between peak G-CSF levels and time to engraftment. A decrease in G-CSF levels preceded engraftment and was paralleled by a rise of nadir leucocyte counts.