Cancer Resources > Cancer News > 2003 > August

Growth factor priming improves chemotherapy outcomes in AML patients

Last Updated: 2003-08-20 17:00:09 -0400 (Reuters Health)

NEW YORK (Reuters Health) - Growth factors can be used to make leukemic cells more sensitive to chemotherapy, which may improve survival for some patients with acute myeloid leukemia (AML), according to a report published in the August 21st issue of The New England Journal of Medicine.

In laboratory studies, exposure to granulocyte colony-stimulating factor (G-CSF) and other growth factors has been shown to enhance the ability of chemotherapy to kill leukemic cells. However, it was unclear if such an approach was clinically useful.

To investigate, Dr. Bob Lowenberg from the Erasmus University Medical Center in Rotterdam, the Netherlands, and colleagues assessed the outcomes of 640 patients with newly diagnosed AML who were randomized to receive chemotherapy with or without concurrent G-CSF therapy.

The chemotherapy regimen in all patients included cytarabine, idarubicin and amsacrine. The median follow-up period was 55 months.

The response rates after induction chemotherapy were not significantly different between the groups, the authors note.

However, among patients in complete remission after induction therapy, the disease-free survival rate at 4 years was 42% for the G-CSF group, significantly higher than that of the non-G-CSF group--33% (p = 0.02). This benefit of G-CSF was largely due to a reduced risk of relapse, the researchers state.

G-CSF therapy did not improve the outcomes of patients with chemotherapy-refractory, unfavorable-risk AML, a finding that explains why an increase in overall survival was not seen in the entire group. Still, for the 72% of patients with standard-risk AML, G-CSF therapy significantly improved overall and disease-free survival.

Although further studies are clearly needed, "the results of our study provide proof of the principle that chemotherapy and sensitization of leukemia cells by hematopoietic growth factors is a plausible strategy for reducing the risk of relapse in patients with AML," Dr. Lowenberg's team notes.

An important focus of future studies is to identify patients who are most likely to respond to growth factor therapy, Dr. Charles A. Schiffer, from Wayne State University School of Medicine in Detroit, states in a related editorial.

However, growth factor therapy is but one of many new treatments that could benefit patients with AML, he notes. Given the abundance of these novel approaches, "we must develop ways of rapidly evaluating new therapies with more efficient trial designs and a minimum of duplicative effort."

N Engl J Med 2003;349:727-729,743-752.

Copyright © 2010 Reuters Limited. All rights reserved.
Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.