J. Glaspy, MD, UCLA Medical Center, Los Angeles, Calif, reported
a costsaving of $4,350 per breast cancer patient using high-dose
infusions of CD34+ cells in peripheral blood progenitor cell
transplants (PBPCTs). The procedure speeds up the recovery of
platelets and neutrophils lost to chemotherapy. Higher levels
of CD34+ cells followed combined use of the investigational
stem cell factor (SCF) and filgastrim (G-CSF) in some patients.
|Background information||Agents effective in treating cancer damage or kill healthy
cells such as platelets and neutrophils. The immune system
suffers from the loss of neutrophils. A decrease in platelets
puts normal blood clotting at risk. Both adverse changes can
be corrected by giving bone marrow or peripheral blood progenitor
cells and platelets.
PBPCT involves removing stem cells from peripheral blood before high-dose chemotherapy for storage and later infusion. G-CSF, a growth factor, activates bone marrow stem cells from which blood cells eventually develop. According to Glaspy, G-CSF use allows more PBPCTs and fewer inpatient hospital days than bone marrow transplants. Addition of another growth factor, SCF, might supplement the activity of G-CSF and further lower in-hospital cost.
Blood stem cells carry the CD34+ antigen. So, the number of CD34+ cells in peripheral blood may be used as a marker for stem cell content and could help estimate the level of blood cell replenishing.
|Study methodology||High risk breast cancer patients from a multicenter Phase III
trial provided information for retrospective analysis. The 186
patients had been randomized before in a comparative study on
G-CSF and SCF, both mobilizers of blood stem cells. At baseline,
the groups were similar (p>0.05) for disease stages and average
Each patient received G-CSF alone as 10 mcg/kg/day or with added SCF (20 mcg/kg/day). Up to five administrations were allowed to achieve 5 million CD34+ cells per kilogram. The cells were stored and later infused after high-dose chemotherapy.
|Clinical results||The combination treatment group needed significantly fewer
infusions to obtain the targeted yield of CD34+ cells (p<0.05).
Also, 67% of the patients infused with G-CSF plus SCF reached
the desired level of CD34+ cells compared with 48% treated with
G-CSF alone (p<0.05).
Patients receiving high doses of CD34+ cells fared better than the low-dose group as seen below:
|Cost/benefit data||Excluding the cost of SCF and its administration, Glaspy and
coworkers used the following schedule:
A 100-day period after infusion of CD34+ cells served as the cut-off for costing hospital days, platelet transfusions, G-CSF administrations, and physician visits.
The cost for patients producing and responding to high-dose CD34+ cells averaged $41,550 compared with $46,460 in the low-dose group (p<0.01). Adjusting for covariates such as age, disease stage, and number of previous chemotherapy cycles lowered the difference to $4,350 (p=0.02).
|Investigator conclusions||According to Glaspy and coworkers, "Infusing at least 5 million per kg CD34+ cells is associated with significant cost savings post-PBPC transplant. Further studies with a randomized design will be useful to more precisely measure the magnitude of cost savings associated with infusing (a) higher CD34+ dose."|
|Conrad comments||This study shows a significant overall savings in breast cancer patients producing and responding to a CD34+ cell concentration of at least 5 million per kilogram. Can the contribution of SCF be defined beyond the need for fewer infusions of CD34+ cells by comparing the G-CSF alone group vs the combined treatment group? Perhaps a direct comparison of SCF and G-CSF is needed.|
Presented at The American Society of Hematology (ASH) Meeting, December 5-9, 1997
Copyright © 1998 Conrad Group, Inc. All Rights Reserved
Eugene A. Conrad, PhD, MPH / ISSN 1078-2230 / February 1998
Send comments to: ConradNote@aol.com