autologous blood and marrow transplantation - Blog Science ...

150 Chapter 4: Lymphoma
age, sex, diagnosis, or performance status. Neutrophil recovery >500/pL occurred a
median of 11 days (range 9-16) in the overnight storage group compared with 10.5
days (range 9-21) in the immediate processing group (P=0.421). Similarly, platelet
transfusion independence did not differ significantly between the two groups: 13 (range
7-43) days in the overnight storage group vs. 13.5 (range 8-53) days in those assigned
to immediate processing (>°=0.933). Storage of PBPC overnight at 4°C did not affect
the number of CD34 +
cells available for selection, the number of leukapheresis
procedures necessary to reach 2X10 6
CD34 +
cells/kg, or the percentage of CD34 +
cells
in the enriched product after collection. Storage of PBPCs overnight at 4°C may allow
the combining of multiple-day collections, thereby decreasing costs associated with
CD34 +
cell selection.
INTRODUCTION
Autologous hematopoietic progenitor cell transplantation is used increasingly
as a form of anticancer therapy. 1
In recent years, hematopoietic progenitor cells
have been collected more often from blood than bone marrow, since hematopoietic
reconstitution appears faster. 2
Although one study reported that in lymphoma
patients there was less than a 1 log difference between blood and marrow sources
for number of tumor cells contaminating the graft, several publications note that
blood stem cell grafts contain significantly fewer malignant cells than bone
marrow. 3-7
Transplantation of these neoplastic cells carries the risk of infusing
sufficient numbers of clonogenic cells to cause relapse. 5
' 68,9
Many techniques have been developed to eliminate unwanted malignant cells in
the autologous graft, but such techniques often are associated with substantial loss
of hematopoietic stem and committed progenitor cells, leading to delayed bone
marrow recovery. 1011
Alternative approaches include the selection of CD34 +
cells,
which has been reported to reduce the number of contaminating tumor cells by 1-3
logs in autografts of patients with non-Hodgkin's lymphoma, 12
multiple
myeloma, 13
and breast cancer, 14
while still providing for an engraftment rate
comparable to unselected autografts. 1516
Since lymphoma cells do not express the
CD34 surface marker, CD34 selection of autografts may provide a feasible method
to improve the outcome of relapsed lymphoma patients. 17
We previously investigated the use of a CD34 immunoaffinity column
(CEPRATE SC; CellPro, Bothell, WA) for positive selection of CD34 +
cells from the
peripheral blood of patients with advanced lymphoma. 18
Median times to neutrophil
and platelet engraftment were rapid when the leukapheresis was processed on the
same day it was collected, at 11 and 13 days, respectively. In an effort to optimize
usage of the immunoaffinity columns, leukapheresis products for 11 patients were
stored overnight at 4°C before processing. Although overnight storage did not affect
neutrophil engraftment (median 11 days, range 11-14), platelet engraftment was