Absence of breast cancer cells in a single-day peripheral blood progenitor cell collection after priming with cyclophosphamide and granulocyte-macrophage colony-stimulating factor.
The effect of priming on occult tumor cell involvement of peripheral blood (PB) and PB progenitor cell (PBPC) collections is poorly characterized. Using sensitive immunocytochemistry (ICC) and tumor clonogenic assays (TCA) specific for epithelial-derived tumor cells, hematopoietic specimens were analyzed for PBPC and occult tumor cell involvement in 28 patients with chemotherapy-sensitive stage IIIB or IV breast cancer. Before PBPC priming, tumor was detected by ICC in PB of 1 of 23 (4%) patients and in bone marrow (BM) harvests of 4 of 27 (15%) patients. Fifteen days after cyclophosphamide and granulocyte-macrophage colony-stimulating factor (GM-CSF) priming, 2 of 28 (7%) patients had ICC-positive PBPC collections. The median amplification of CD34+ PBPC during this time was over 19-fold (range, < 1 to 199). One patient had pretreatment tumor involvement of both PB and BM. One patient grew tumor colonies in TCA; the PB and BM were ICC- and TCA-positive, but the PBPC collection was ICC-positive and TCA-negative. After cytoreduction with conventional-dose chemotherapy, patients with advanced breast cancer and histologically negative BM biopsy specimens have rare tumor cell involvement of PB and BM. Despite effective PBPC priming with cyclophosphamide and GM-CSF, clonogenic breast cancer cells were not found in the PBPC collection performed on day 15.
Division of Medical Oncology, Johns Hopkins Oncology Center, Baltimore, MD 21287.
J L
JL
Passos-Coelho
A A
AA
Ross
T J
TJ
Moss
J M
JM
Davis
A M
AM
Huelskamp
S J
SJ
Noga
N E
NE
Davidson
M J
MJ
Kennedy
D000328:Adult; D001853:Bone Marrow / Q000473:pathology*; D016465:Bone Marrow Purging / Q000379:methods; D001943:Breast Neoplasms / Q000473:pathology* / Q000628:therapy*; D003520:Cyclophosphamide / Q000627:therapeutic use*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000627:therapeutic use*; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D009367:Neoplasm Staging; D012680:Sensitivity and Specificity
D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D003520:Cyclophosphamide