Mobilization of Peripheral Blood Progenitor Cells Following CHOP Treatment Combined with Delayed Granulocyte Colony-Stimulating Factor Administration in Patients with Non-Hodgkin's Lymphoma

The kinetic change in peripheral blood progenitor cells (PBPC) during 3 to 6 cycles of standard CHOP regimen supported with human recombinant granulocyte colony-stimulating factor (rG-CSF) was investigated in three patients with newly diagnosed intermediate grade, diffuse large cell type, non-Hodgkin's lymphoma (NHL) without bone marrow invasion. Patients were given rG-CSF subcutaneously (2 mu g/kg/day) initiated when total leukocytes was < 3.0 x 10(9)/1. When the leukocyte count remained at >3.0 x 10(9)/1, rG-CSF was started 10 days following the prior CHOP. Treatment with rG-CSF was discontinued after the leukocyte count reached >10.0 x 10(9)/1, and CHOP was started the next day (CHOP-G regimen). The number of PBPC was monitored by clonal assay in patients 1-3. No severe leukopenia with <0.5 x 10(9)/1 of neutrophils was seen in any patient. Colony-forming unit granulocyte-macrophage (CFU-GM) significantly increased after 2-3 days of consecutive administration of rG-CSF. The magnitudes of maximum amplification of CFU-GM in patients 1, 2, and 3, were 56-fold (during 3 cycles of CHOP-G), 216-fold (during 2 cycles), and 67-fold (during 4 cycles), respectively, and the absolute numbers of the maximum CFU-GM/ml blood were 983, 7,568, 9,865, respectively. In one patient who was given 6 cycles of CHOP-G, the peak values of mobilized CFU-GM in each cycle did not substantially decrease until 6 cycles of CHOP-G had been completed. Thus, the CHOP-G regimen described here seems to be very efficient increasing the circulating CFU-GM prior to harvesting PBPC.