PBSC collection after high dose chemotherapy followed by G-CSF in patients with malignancies: analysis of results regarding factors affecting the yield of hemopoietic progenitors.

High-dose non ablative chemotherapy followed by growth factors efficiently mobilizes and amplifies Peripheral Blood stem Cells (PBSC). Cytofluorimetric PBSC monitoring reduces the number of leukapheresis needed to collect sufficient amounts of progenitors to restore hemopoiesis after myeloablative therapy. Twenty-eight patients, affected by lymphoproliferative disorders, were primed with non myeloablative chemotherapy followed by G-CSF 5 micrograms/kg/die subcutaneously, until leukapheresis. A total number of 90 leukaphereses was performed (median: 3 per patient) using blood cell separator CS 3000 Plus Baxter; we collected 1 +/- 0.8 x 10(8)/kg mononuclear cells (MNC), 6 +/- 9 x 10(4)/kg CFU-GM and 4 +/- 5 x 10(6) CD34+ cells for each procedure. The statistical analysis showed that the number of progenitors collected was dependent on the age, number and type of previous chemotherapies and interval between the last chemotherapy and the priming; the type of priming, type and status of disease, sex, and bone marrow involvement were not significant. Duration of neutropenia after megachemotherapy was very short; in two cases platelet support was necessary and only two patients needed hospitalization. Our experience shows that high-dose non ablative chemotherapy followed by G-CSF is safe and yields large amounts of PBSC; several factors influence the quality of collections mainly regarding age and the previous treatment.