title: Who should be really considered as a poor mobilizer in the plerixafor era?
abstract: Patients with a number of peripheral CD34+ cells ≥20/μL have recently been defined in the literature as "poor mobilizers". We retrospectively reviewed medical records from a total of 248 patients affected by hematological malignancies or solid tumors undergoing peripheral blood stem cell collection following chemotherapy plus G-CSF. On the basis of the CD34+ cell peak in peripheral blood following mobilization therapy, patients were defined as good mobilizers (group A, CD34+ cells ≥20/μL), relative poor mobilizers (group B, CD34+ cells <20 and ≥8/μL) and absolute poor mobilizers (group C, CD34+ cells <8/μL). One hundred and seventy-seven (71%) patients resulted good mobilizers, 35 (14%) patients relative poor mobilizers and 36 (15%) patients absolute poor mobilizers. Target of stem cell collection was ≥2.0×10(6) CD34+cells/kg for each transplantation procedure. All patients in group A, 20 patients in group B (57%) and 1 patient in group C (2.7%) were able to collect ≥2.0×10(6) CD34+cells/kg. The multivariate analysis confirmed that more than three lines of previous chemotherapy and a previous autologous PBSC transplantation negatively affect mobilization of CD34+ cells in peripheral blood. Our data suggest that a number of CD34+ cells ≥20/μL does not always result in a failed stem cell collection and in fact in our patient series more than 70% of the patients defined as poor mobilizers have indeed collected the minimum number of 2.0×10(6) CD34+cells/kg required for a successful transplantation. The use of new agent such as CXCR4 antagonist plerixafor might further improve mobilization efficacy in such patients.
authors.affiliation: Stem Cell Collection Unit, European Institute of Oncology, Milan, Italy.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Andreola
authors.forename: Anna
authors.initials: A
authors.lastname: Vanazzi
authors.forename: Davide
authors.initials: D
authors.lastname: Radice
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Babic
authors.forename: Cristina
authors.initials: C
authors.lastname: Rabascio
authors.forename: Mara
authors.initials: M
authors.lastname: Negri
authors.forename: Giovanni
authors.initials: G
authors.lastname: Martinelli
authors.forename: Daniele
authors.initials: D
authors.lastname: Laszlo
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D019380:Anti-HIV Agents / Q000008:administration & dosage*; D001596:Benzylamines; D000080027:Cyclams; D005260:Female; D016179:Granulocyte Colony-Stimulating Factor / Q000008:administration & dosage*; D019650:Hematopoietic Stem Cell Mobilization / Q000379:methods*; D006571:Heterocyclic Compounds / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000628:therapy*; D036102:Peripheral Blood Stem Cell Transplantation; D019718:Receptors, CXCR4 / Q000037:antagonists & inhibitors; D012189:Retrospective Studies; D012307:Risk Factors; D014182:Transplantation, Autologous
chemical_list: D019380:Anti-HIV Agents; D001596:Benzylamines; C527276:CXCR4 protein, human; D000080027:Cyclams; D006571:Heterocyclic Compounds; D019718:Receptors, CXCR4; D016179:Granulocyte Colony-Stimulating Factor; C088327:plerixafor