Back fractures common after stem cell transplant

By Martha Kerr

NEW YORK (Reuters Health) - More than one third of children and adolescents who undergo allogenic stem cell transplantation have thinning of their bones, and one in five had crushed vertebrae in their backs, Finnish researchers report.

Allogeneic stem cell transplantation is used to treat leukemia and a variety of other cancerous and non-cancerous conditions. Allogeneic means that the cells from a closely matched donor are removed and implanted in the patient. The goal of therapy is typically to replace diseased cells of the bone marrow with fully functioning cells from another person.

Dr. Mervi Taskinen of the University of Helsinki and colleagues evaluated the bone health of 44 children a few years after they underwent stem cell transplantation. Study subjects were 18.5 years of age or younger; at the time of transplantation, they were around 10 years old.

Sixteen patients had evidence of bone thinning, the investigators report in the journal Cancer. These children were similar to the other 28 patients in terms of clinical characteristic and laboratory test results.

Bone thinning "was especially evident at the hip" in the pubertal and postpubertal children, the investigators say.

Nine patients (20 percent) had vertebral fractures and five patients (11 percent) had other fractures. Seven of the nine vertebral fractures caused no symptoms.

The investigators conclude that because of the heightened risk of bone thinning and vertebral fractures, children undergoing stem cell transplantation should be carefully monitored after the procedure and possibly given drugs that help strengthen the bones.

SOURCE: Cancer, July 15, 2007.