Effect of CD34 cell dose on hematopoietic reconstitution and outcome in 508 patients with multiple myeloma undergoing autologous peripheral blood stem cell transplantation.
BACKGROUND
We analyzed the hematopoietic reconstitution and outcome of 508 patients with multiple myeloma (MM) with respect to the number of CD34+ cells reinfused at our center.


METHODS
Each cohort of 390 patients (unselected CD34+ cell transplant) and 118 patients (CD34+ selected transplant) was divided into four subgroups. Among the 390 transplantations, 86 patients received a high dose (HD-) of > or =6.50 x 10(6) unselected CD34+ cells/kg, 116 patients a low dose (LD-) of <3.00 x 10(6) CD34+ cells/kg. Among the patients treated with CD34+ selected PBSC, 34 received > or =6.50 x 10(6) CD34+ cells/kg (HD+) and 16 <3.00 x 10(6) CD34+ cells/kg (LD+).


RESULTS
HD- patients experienced a reduced median time to leukocyte (13 d vs. 14 d) (P < 0.001) and platelet reconstitution >20 x 10(9)/L (10 d vs. 12 d) (P < 0.001). Similarly, HD+ showed a reduced median time to leukocyte (12 d vs. 15 d) (P < 0.001) and platelet recovery >20 x 10(9)/L (10 d vs. 11 d) (P = 0.058). CD34+ cell-dose was significant for long-term platelet recovery at day 360 (unselected transplant P = 0.015, selected transplant P = 0.023). Number of transplanted CD34+ cells had no significant impact on transplant related mortality, overall survival or CR/PR rates within 100 d. In terms of supportive care the differences of high-/low-dose grafts were minimal.


CONCLUSIONS
These results confirm that high doses of CD34+ PBSC shorten hematopoietic reconstitution and reduce hospitalization. Nevertheless secure engraftment results from transplantation of 2.00-3.00 x 10(6) CD34+ cells/kg. As 60% of our pretreated patients are able to collect > or =5.00 x 10(6) CD34+ cells/kg within a single leukapheresis, division into two or more freezing bags allows safe tandem transplantation in the majority of MM patients.
Klaus
Jens
J
Department of Internal Medicine V, University Heidelberg, Heidelberg, Germany.
Herrmann
Doris
D
Breitkreutz
Iris
I
Hegenbart
Ute
U
Mazitschek
Uta
U
Egerer
Gerlinde
G
Cremer
Friedrich W
FW
Lowenthal
Ray M
RM
Huesing
Johannes
J
Fruehauf
Stefan
S
Moehler
Thomas
T
Ho
Anthony D
AD
Goldschmidt
Hartmut
H
D000328:Adult; D000368:Aged; D018952:Antigens, CD34 / Q000096:biosynthesis*; D015331:Cohort Studies; D004306:Dose-Response Relationship, Immunologic; D005260:Female; D006085:Graft Survival; D006410:Hematopoiesis; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000175:diagnosis / Q000628:therapy*; D036102:Peripheral Blood Stem Cell Transplantation; D010976:Platelet Count; D011379:Prognosis; D015996:Survival Rate; D019172:Transplantation Conditioning; D014182:Transplantation, Autologous; D016896:Treatment Outcome
D018952:Antigens, CD34