Large-volume leukapheresis in pediatric patients: pre-apheresis peripheral blood CD34+ cell count predicts progenitor cell yield.
OBJECTIVE
In children it is very important to optimize PBPC harvesting and to reduce the number of leukaphereses per patient. The value of pre-apheresis peripheral blood CD34+ cell concentration as a predictor of PBPC yield was studied in 23 pediatric patients with hematologic and non-hematologic malignancies in order to optimize duration of PBPC collection.


METHODS
The patients underwent 25 stem-cell mobilization episodes with G-CSF alone and 40 large-volume leukapheresis procedures. Peripheral blood and harvested CD34+ cell concentrations were analyzed by means of flow cytometry.


RESULTS
Using linear regression analysis, a highly significant correlation was found between the peripheral blood CD34+ cell count and the CD34+ cells/kg patient body weight collected on the apheresis day (r = 0.826, p = 0.0001). The results indicate that at least 1 x 10(6)/kg CD34+ cells can be harvested during one leukapheresis procedure in all patients if the pre-apheresis blood CD34+ cell count is > or = 30/microL and a CD34+ cell target of > or = 5 x 10(6)/kg is achieved in at least 80% of patients if this value is > or = 50 CD34+ cells/microL processing a median blood volume of 438.7 mL/kg (range, 207-560) over a median time of 232.5 minutes (range, 182-376).


CONCLUSIONS
Our results suggest that the number of CD34+ cells harvested in a single large-volume leukapheresis can be predicted from the measurement of peripheral blood CD34+ cell concentration on the collection day.
Díaz
M A
MA
Department of Pediatric Hematology and Oncology, Niño Jesús Children's Hospital, Autonomous University of Madrid, Spain. 2635m23d@mail.sendanet.es
Garcia-Sanchez
F
F
Lillo
R
R
Vicent
M G
MG
Vicario
J L
JL
Madero
L
L
D000293:Adolescent; D018952:Antigens, CD34 / Q000032:analysis*; D001772:Blood Cell Count; D001835:Body Weight; D002648:Child; D002675:Child, Preschool; D005260:Female; D000069585:Filgrastim; D005434:Flow Cytometry; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology; D019337:Hematologic Neoplasms / Q000097:blood / Q000628:therapy; D019650:Hematopoietic Stem Cell Mobilization; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells; D006801:Humans; D007223:Infant; D007937:Leukapheresis / Q000379:methods*; D016014:Linear Models; D008297:Male; D009369:Neoplasms / Q000097:blood / Q000628:therapy; D011994:Recombinant Proteins
D018952:Antigens, CD34; D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor; D000069585:Filgrastim