View Full Version : Marrow, Stem Cell Donation Safe

12-07-2010, 11:03 AM
By Michael Smith, North American Correspondent, MedPage Today
Published: December 06, 2010
Reviewed by Zalman S. Agus, MD; Emeritus Professor
University of Pennsylvania School of Medicine and
Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner

ORLANDO -- Donating bone marrow or peripheral blood stem cells to help strangers with blood cancers is safe, a researcher said here.

In what is probably the largest analysis yet of the health of such unrelated donors, there was no evidence of an excess of adverse health effects, according to Alexander Schmidt, MD, PhD, of the DKMS German Bone Marrow Donor Center in Tubingen, Germany.

Specifically, there was no sign of hematological cancers -- a concern raised in recent years by some published case reports and some experimental research, Schmidt told reporters at the annual meeting here of the American Society of Hematology.

The findings "underscore" the safety of the donation procedures, Schmidt said.Action Points
Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.

Point out that this large, retrospective study found no evidence that donation of peripheral blood stem cells or of bone marrow might be unsafe procedures.
The issue is vital, he said, because unrelated donors are performing a "purely altruistic act" and their safety should be paramount.

One concern had been that the granulocyte colony-stimulating factor compounds used in donors giving peripheral blood stem cells might increase the risk of leukemia among donors, Schmidt said.

But analyzing the issue is not easy. Effects are likely to be small and therefore a study would need a large number of participants to detect them, Schmidt said. Furthermore, prospective analysis is difficult because healthy donors in general do not want to answer health questions repeatedly over time.

To try to overcome those issues, Schmidt and colleagues conducted a retrospective analysis of donors in their center in Germany, which -- with 2.3 million donors -- is the world's largest.

They designed a four-item questionnaire that asked about the donor's general health status, need for inpatient care long-term medical treatment since donation, use of prescription drugs, and willingness to donate again.

That questionnaire was sent to all 15,456 donors who had donated peripheral blood stem cells or bone marrow before Jan. 31, 2009. All told, 12,559 -- or 81.3% -- responded, Schmidt said, with a total of 55,229 observation years.

The donors reported 85 malignancies of all types, Schmidt said. Using that data and the known prevalence of the various cancers, he and colleagues calculated standardized incidence ratios, which showed no evidence of an excess of disease among the donors.

None was significant, except for melanoma among bone marrow donors, where the incidence ratio was 3.0 with a 95% confidence interval from 1.4 to 5.7. But, Schmidt said, that is a probably a "statistical artifact" since there is no known mechanism that could link a bone marrow donation to skin cancer.

Overall, more than 92% of the donors said they were in good health, the researchers found, and more than 90% said they'd be willing to donate again.

Donors who gave peripheral blood stem cells -- rather than bone marrow or both -- were less likely to have needed inpatient or long-term treatment, but multivariate analysis found that was because they tended to younger and male, Schmidt said. The same was true for the need for prescription drugs.

The published papers suggesting a risk had no apparent effect on the public willingness to donate, Schmidt told MedPage Today, although a change in counseling guidelines required doctors to describe the possible risks.

"This is reassuring," said Armand Keating, MD, of the University of Toronto and the society's vice president. Keating was not involved in the research but moderated a press conference at which it was presented.

At issue were observations published in 2006 that some donors had developed acute myeloid leukemia, and experimental research published in 2004 that found in some healthy donors chromosome irregularities also found in leukemia patients.

But Keating, like Schmidt, didn't think the concerns raised by the research had affected the public. As for clinicians, he told MedPage Today, "The sense in the community was that the studies were a bit underpowered."

The study had no external financing. Schmidt said he had no relevant conflicts to declare.

Keating had no relevant financial disclosures.

Primary source: American Society of Hematology
Source reference:
Schmidt AH, et al "Follow-up of 12,559 unrelated donors of peripheral blood stem cells or bone marrow" ASH 2010; Abstract 365.