Stem Cell Transplantation May Improve Survival Of MDS Patients With Missing Chromosomes (EHA 2012)
Published: Aug 23, 2012 3:44 pm
Mayo Clinic researchers have found that stem cell transplantation may extend the survival of myelodysplastic syndromes patients with missing chromosomes.
However, the study was done retrospectively, and patient age may have affected the results, as patients who underwent stem cell transplantation were typically much younger than those who received other treatment methods.
The findings were presented at the 2012 Congress of the European Hematology Association (EHA) in The Netherlands.
DNA is stored inside cells in the form of chromosomes. Most human cells contain 23 pairs of chromosomes.
Some myelodysplastic syndromes (MDS) patients develop chromosomal abnormalities, in which some of their chromosomes have extra DNA (addition) or are missing parts of DNA (deletion).
Monosomal karyotype is a type of chromosomal abnormality where an entire chromosome is missing, leaving its partner unpaired.
According to the researchers, MDS patients with monosomal karyotype have a poorer prognosis than patients with other chromosomal abnormalities. They typically survive for a median of seven months.
Stem cell transplantation is currently the only potential cure for MDS. During the procedure, the patient first receives either high-dose chemotherapy, which destroys all of the patient’s unhealthy, but also healthy, bone marrow stem cells (myeloablative approach), or less intensive chemotherapy, which does not destroy all stem cells (non-myeloablative approach). The patient then receives stem cells from a healthy donor that will replace the destroyed stem cells.
However, according to the Mayo researchers, little is known about the effects of stem cell transplantation in MDS patients with monosomal karyotype.
They therefore analyzed data from 123 MDS patients with monosomal karyotype who were treated at their institution.
They defined monosomal karyotype as either having two or more unpaired chromosomes or one unpaired chromosome in addition to one chromosome with an addition or a deletion.
About one-quarter of the patients (26 percent) included in the analysis received stem cell transplants. These patients had a median age of 52 years at diagnosis.
Of the patients who received stem cell transplants, 59 percent were treated with myeloablative chemotherapy, and 41 percent were treated with non-myeloablative chemotherapy.
There were no differences in types of MDS between the two groups.
Of the patients who received a transplant, 38 percent relapsed within a median of four months after their transplant.
The researchers found that patients who received a stem cell transplant survived significantly longer (17 months) than patients who did not undergo a transplant (4 months).
About one-third of patients (34 percent) who received stem cell transplants survived at least four years after their initial MDS diagnosis.
About half of the transplant patients (56 percent) developed acute graft-versus-host disease (occurring within 100 days post-transplant). Graft-versus-host disease is a common transplant-related complication in which the donor’s immune cells recognize the patient’s cells as foreign and attack them.
Chronic graft-versus-host disease (occurring after the first 100 days post-transplant) developed in 44 percent of patients.
Almost a third (31 percent) of the patients who underwent stem cell transplantation died due to reasons unrelated to their MDS relapsing. The researchers do not elaborate on what those reasons were. However, treatment-related mortality can be as high as 30 percent in MDS patients undergoing stem cell transplants (see related Beacon news), and it therefore may account for much of the non-relapse mortality in the current study.
- Researchers Identify A Specific Chromosomal Abnormality In Myelodysplastic Syndromes Patients That Indicates More Severe Disease
- Multiple Unpaired Chromosomes May Not Be Worse Than Other Chromosomal Abnormalities In MDS
- Spanish Study Argues Monosomal Karyotype Does Not Independently Impact MDS Prognosis
- Researchers Identify Factors That Predict Better Survival In MDS After Stem Cell Transplantation (EHA 2012)
- New Study Argues For Strong Link Between Monosomal Karyotype And MDS Prognosis (ASH 2012)