Hematopoietic progenitor cell collection and neoplastic cell contamination in breast cancer patients receiving chemotherapy plus granulocyte-colony stimulating factor (G-CSF) or G-CSF alone for mobilization.
BACKGROUND
We compared hematopoietic progenitor cell (HPC) collection and neoplastic cell contamination in breast cancer patients given cyclophosphamide (CTX) plus granulocyte-colony stimulating factor (G-CSF) or G-CSF alone for mobilization.


METHODS
In 57 stage II-III breast cancer patients, CD34+ cells, colony-forming units-granulocyte macrophage (CFU-GM), early HPC and breast cancer cells were counted in HPC collections obtained after CTX plus G-CSF (n = 27) or G-CSF-alone mobilization (n = 30).


RESULTS
The CD34+ cell collection was about two-fold greater after CTX plus G-CSF mobilization (11.0 +/- 7.9 vs. 5.8 +/- 3.5 x 10(6)/kg, P < 0.001). Similarly, the total number of CFU-GM, CD34+CD38- cells and of week-5 cobblestone area forming cells (CAFC) collected was significantly higher in patients mobilized with CTX plus G-CSF. Breast cancer cells were found in the apheresis products of 22% of patients mobilized with CTX plus G-CSF and in 10% of patients mobilized with G-CSF alone (P = 0.36). Of seven patients who failed G-CSF-alone mobilization and eventually underwent chemotherapy plus G-CSF mobilization, none had cytokeratin-positive cells after G-CSF mobilization, whereas four out of seven had cytokeratin-positive cells after chemotherapy plus G-CSF (P = 0.07 by chi 2 test).


CONCLUSIONS
The CTX plus G-CSF mobilization protocol was associated with a significantly higher HPC collection. However, this benefit was not accompanied by a reduction in the incidence of tumor-contaminated HPC graft.
Bertolini
F
F
Division of Medical Oncology and Experimental Medicine, IRCCS Maugeri Foundation, IRCCS San Matteo Hospital, Pavia, Italy. f.bertolini@agora.stm.it
Lanza
A
A
Peccatori
F
F
Zibera
C
C
Gibelli
N
N
Perotti
C
C
Da Prada
G A
GA
Torretta
L
L
Cocorocchio
E
E
Martinelli
G
G
Robustelli della Cuna
G
G
D000328:Adult; D018952:Antigens, CD34; D018906:Antineoplastic Agents, Alkylating / Q000008:administration & dosage*; D001943:Breast Neoplasms / Q000473:pathology / Q000628:therapy*; D002469:Cell Separation; D003131:Combined Modality Therapy; D003520:Cyclophosphamide / Q000008:administration & dosage*; D005260:Female; D016179:Granulocyte Colony-Stimulating Factor / Q000008:administration & dosage*; D019650:Hematopoietic Stem Cell Mobilization; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D008875:Middle Aged
D018952:Antigens, CD34; D018906:Antineoplastic Agents, Alkylating; D016179:Granulocyte Colony-Stimulating Factor; D003520:Cyclophosphamide