Appropriate timing of G-CSF use after mobilization chemotherapy significantly increases the yield of CD34+ cells in autoPBSCT.

The yield of CD34+ cells collected by apheresis for autologous peripheral blood stem cell (PBSC) transplantation was greatly increased when the appropriate timing was determined to begin using G-CSF after COAEP (Cytoxan, Vinblastine, Arabinosylcytosin, Etoposide and Prednisone) mobilization. Twenty-nine patients with lymphoma or multiple myeloma (MM) received the same mobilization chemotherapy, including cytoxan (CTX) 400 mg/m(2) d1; vinblastine (VLB) 2 mg/m(2) d1; Ara-C 60 mg/m(2) x 5d; vp-16 60 mg/m(2) x 5d; and prednisone 40 mg/m(2) x 5d. The historical control group (12 cases) received subcutaneous G-CSF (filgrastim) at the first restoration after the initial nadir of the peripheral WBC count. The experimental group (17 cases) received G-CSF during the steady rise of the WBC count (end of fluctuating after initial nadir). G-CSF was given in a single daily subcutaneous dose of 5 microg/kg until the final PBSC apheresis. When the peripheral WBC and mononuclear cell (MNC) counts reached 10 x 10(9)/L and 1 x 10(9)/L, respectively, leukapheresis was carried out using the COBE Spectrablood cell separator. Despite comparable treatment with alkylating agents, a significantly increased yield of CD34-positive cells was observed in the experimental group (32 x 10(6)/kg) compared with the historical control group (3.1 x 10(6)/kg) (P = 0.0182). This result indicates the importance of appropriate timing for the use G-CSF after mobilization chemotherapy to increase the CD34+ cell yield.