Stem cell transplants improve survival for some leukemia patients: study
Last Updated: Tuesday, June 9, 2009 | 6:17 PM ET
CBC News
Stem cell transplants improve survival among people with a common form of leukemia, researchers said Tuesday.
Acute myeloid leukemia (AML) is the most common form of acute leukemia.
It is usually treated with chemotherapy to produce a first remission, which nearly 70 per cent of patients under the age of 60 achieve, researchers said.
Not every cancer cell is eradicated, however, so relapses can occur, since the blood and bone marrow haven't been restored to normal, said study author John Koreth of the Dana Farber Cancer Institute in Boston.
To achieve a cure, doctors may use more chemotherapy, stem cells transplants from a patient's own bone marrow, or stem cells from a donor — allogenic transplant — but it wasn't clear which approach was best.
In Tuesday's issue of the Journal of the American Medical Association, Koreth and his colleagues concluded allogenic transplants clearly boosted the survival rate of patients with poor and intermediate risk AML.
The risk categories are based on analyzing chromosomes to predict a patient's response to treatment.
Without a donor transplant, the survival range for those in the poor-risk group is 15 per cent to 20 per cent at five years. With a donor transplant, the chance of disease-free survival at five years improved to about 33 per cent, the team found.
For patients in the intermediate group, a donor plants improved survival to around 40 per cent — high enough that it could become the new standard for these patients, Koreth said.
"For intermediate risk even the experts were stumped," Koreth said in a release.
"We are coming along and saying actually it's fairly straightforward. You should strongly consider an allogenic transplant rather than the alternative treatments based on the cumulative experience of several thousands of patients."
The transplants carry a higher risk of serious side-effects but resulted in a lower rate of relapse, the researchers concluded after analyzing data from 24 clinical trails including more than 6,000 patients.
Developing more sophisticated ways of analyzing genetic risk will help to further pinpoint the best candidates for this type of stem cell transplant, the team said.
