Impaired PBPC collection in patients with myeloma after high-dose melphalan.
BACKGROUND
Tandem stem cell transplantation is an important treatment option for patients with myeloma and some additional tumors. In an attempt to reduce the contamination of the stem cell graft with tumor cells, patients with myeloma who entered complete remission after the first transplant underwent a second episode of mobilization to obtain progenitor cells for the second transplant.


METHODS
Twenty-two patients with myeloma participated in the study. The first mobilization utilized CY, etoposide and filgrastim. The second mobilization used the same regimen, but seven patients received only filgrastim. The interval between the two collection periods was 6 months (median; range 4-9 months). The preparative regimen for the first transplant consisted of melphalan 200 mg/m(2).


RESULTS
The number of total white cells collected during the two collection episodes was similar: 10.8+/-1.6 x 10(8)/kg white cells vs. 11.8+/-1.7 x 10(8)/kg white cells (P=0.63). The collected CD34(+) cell dose was much larger during the first collection: 45.2+/-8.4 x 10(6)/kg vs. 6.9+/-2.7 x 10(6)/kg (P<0.001). Similarly, the collected colony-forming unit (CFU)-GM dose was much larger during the first collection: 295.4+/-59.3 x 10(4)/kg vs. 67.3+/-21.6x10(4)/kg (P<0.001). While the CD34(+) cells collected during the two collection episodes correlated significantly (r=0.55, P<0.01); the first dose was a median of 14.9-fold larger.


CONCLUSIONS
No laboratory parameter was able reliably to predict the results of the second collection. A second mobilization/collection episode as part of a tandem transplant approach carries a considerable risk of failing to obtain sufficient progenitor cells.
Jansen
J
J
Indiana Blood and Marrow Transplantation, Beech Grove, Indiana 46107, USA.
Thompson
Jm
J
Dugan
Mj
M
Wiemann
Mc
M
Hanks
S
S
Greenspan
Ar
A
Akard
Lp
L
D000328:Adult; D000368:Aged; D018906:Antineoplastic Agents, Alkylating / Q000008:administration & dosage / Q000627:therapeutic use*; D005260:Female; D019650:Hematopoietic Stem Cell Mobilization / Q000379:methods; D006412:Hematopoietic Stem Cells / Q000166:cytology; D006801:Humans; D008297:Male; D008558:Melphalan / Q000008:administration & dosage / Q000627:therapeutic use*; D008875:Middle Aged; D009101:Multiple Myeloma / Q000188:drug therapy / Q000628:therapy*; D014182:Transplantation, Autologous
D018906:Antineoplastic Agents, Alkylating; D008558:Melphalan