title: High-dose CD34+ cells are not clinically relevant in reducing cytopenia and blood component consumption following myeloablative therapy and peripheral blood progenitor cell transplantation as compared with standard dose.
abstract: BACKGROUND
  No agreement exists about the number of autologous peripheral blood progenitor cells (PBPCs) to transfuse for optimal hematologic recovery after high-dose chemotherapy.
  
  
  METHODS
  To determine CD34+ cell dosage following high-dose chemotherapy (in terms of hematologic recovery and blood component consumption), the effects of two schedules of CD34+ cell transfusions in a cohort of patients with myeloma or non-Hodgkin's lymphoma were examined. Forty patients (Group 1) received between 2.5 and 5 x 106 CD34+ cells per kg, with a median of 3.4 x 106 per kg following high-dose chemotherapy, and 40 patients (Group 2), selected to match Group 1 for age, diagnosis, prior therapies, and procedure for PBPC mobilization, received a dose of CD34+ cells >5 x 106 per kg, with a median of 8.4 x 106 per kg (5-33).
  
  
  RESULTS
  The median number of days to achieve a neutrophil count of >0.5 x 109 per L and unsupported platelets of >20 x 109 per L was identical for the two groups, but the time required to reach 1.5 x 109 neutrophils per L and 50 x 109 platelets per L was greatly delayed in Group 1. No significant difference was observed for the median number of RBC and platelet transfusions, or for the proportion of patients in each group that did not require either platelet or RBC transfusions.
  
  
  CONCLUSIONS
  Our data confirm a dose-response relationship between CD34+ cell dose transfused and time to hematologic recovery after high-dose chemotherapy. However, the minimal Hb and platelet counts for transfusion independence in the two groups are similar when the CD34+ cell dose is greater than 5 x 106 CD34+ cells per kg. Therefore, our data suggest that it is not necessary to go on with apheresis procedures after 5 x 106 CD34+ cells per kg are harvested to sustain one high-dose chemotherapy.
authors.affiliation: Department of Hematology and the Blood Center, Necker Hospital, Paris, France. francois.lefrere@nck.ap-hop-paris.fr
authors.forename: François
authors.initials: F
authors.lastname: Lefrère
authors.forename: Richard
authors.initials: R
authors.lastname: Delarue
authors.forename: Dominique
authors.initials: D
authors.lastname: Somme
authors.forename: Vincent
authors.initials: V
authors.lastname: Levy
authors.forename: Gandhi
authors.initials: G
authors.lastname: Damaj
authors.forename: Angela
authors.initials: A
authors.lastname: Tu
authors.forename: Raphael
authors.initials: R
authors.lastname: Porcher
authors.forename: Françoise
authors.initials: F
authors.lastname: Audat
authors.forename: Claire
authors.initials: C
authors.lastname: Boulat
authors.forename: Marine
authors.initials: M
authors.lastname: Cavazzana-Calvo
authors.forename: Agnès
authors.initials: A
authors.lastname: Buzyn
authors.forename: Coralie
authors.initials: C
authors.lastname: Belanger
authors.forename: Natacha
authors.initials: N
authors.lastname: Maillard
authors.forename: Olivier
authors.initials: O
authors.lastname: Hermine
authors.forename: Bruno
authors.initials: B
authors.lastname: Varet
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018952:Antigens, CD34 / Q000032:analysis*; D000970:Antineoplastic Agents / Q000008:administration & dosage; D016913:Blood Component Transfusion; D002452:Cell Count; D017707:Erythrocyte Transfusion; D005260:Female; D006085:Graft Survival; D006402:Hematologic Diseases / Q000139:chemically induced / Q000628:therapy*; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000276:immunology; D006801:Humans; D007958:Leukocyte Count; D007970:Leukopenia / Q000139:chemically induced / Q000628:therapy; D008228:Lymphoma, Non-Hodgkin / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000628:therapy; D009504:Neutrophils; D017713:Platelet Transfusion; D019172:Transplantation Conditioning
chemical_list: D018952:Antigens, CD34; D000970:Antineoplastic Agents