Blood, Vol. 94 No. 1 (July 1), 1999:
pp. 340-347
Incidence of Tumor-Cell Contamination in Leukapheresis Products of
Breast Cancer Patients Mobilized With Stem Cell Factor and Granulocyte
Colony-Stimulating Factor (G-CSF) or With G-CSF Alone
Wilbur A. Franklin,
John Glaspy,
Sean M. Pflaumer,
Roy B. Jones,
Lisa Hami,
Charles Martinez,
James R. Murphy, and
Elizabeth J. Shpall
From the Bone Marrow Transplant Unit and Department of Pathology,
University of Colorado Health Science Center, Denver, CO; and the Bone
Marrow Transplant Unit, University of California Los Angeles Medical
Center, Los Angeles, CA.
We have assessed tumor contamination of peripheral blood progenitor
cells (PBPC) in 203 high-risk breast cancer patients who were
prospectively randomized to mobilization with stem cell factor (SCF)
plus granulocyte colony-stimulating factor (G-CSF) versus G-CSF alone.
The patients then received high-dose cyclophosphamide, cisplatin, and
carmustine (BCNU) with PBPC support. One bone marrow aspirate obtained
before treatment, one whole blood specimen obtained before cytokine
infusion, and one to five leukapheresis products were tested for the
presence of tumor cells by an alkaline phosphatase immunocytochemical
technique with a targeted sensitivity of 1.7 tumor cells per
106 hematopoietic cells. Tumor cells were detected in the
bone marrow, peripheral blood, and/or PBPC of 21 patients (10%). In 14 patients, bone marrow specimens were tumor-positive; in seven patients, premobilization whole blood specimens were tumor-positive, and in eight
patients, leukapheresis products were tumor-positive. In five patients,
repetitive or multiple specimens were tumor-positive, and in three
cases, marrow, peripheral blood, and PBPC products were all
tumor-positive. Nine of the patients in whom tumor cells were found in
marrow or peripheral blood were clinical stage II to III and 12 were
clinical stage IV. Nine of the tumor-positive patients were in the SCF + G-CSF arm and 12 were in the G-CSF arm. Tumor cells were detected
in leukapheresis products of eight patients: three in the G-CSF + SCF
arm and five in the G-CSF arm. We conclude that detectable tumor-cell
contamination of bone marrow, peripheral blood, and/or PBPC occurred in
approximately 10% of patients in this trial and was observed in stage
II to III patients, as well as in stage IV patients. No significant
difference could be found in the rate of PBPC tumor-cell contamination
between patients who received SCF + G-CSF compared with those who
received G-CSF alone. Neither mobilization regimen was found to
increase the rate of tumor-cell contamination when control
premobilization blood samples were compared with leukapheresis products.
