Obesity does not affect leukemia treatment

By Anthony J. Brown, MD

NEW YORK (Reuters Health) - Obesity has little impact on the success of blood cell transplants for acute myeloid leukemia, the most common reason for performing such transplantations, according to study findings presented at the American Society of Hematology annual meeting in San Francisco.

Technically known as hematopoietic stem cell transplantation, the procedure involves reconstituting the leukemia patient's body with normal blood cells derived from stem cells in the blood or bone marrow. The cells may come from the patients themselves (autologous) or from another person (allogeneic).

"There has been a long-standing belief that obese patients would suffer much poorer outcomes than normal weight patients but that is not what we found," lead author Dr. Willis H. Navarro, from the National Marrow Donor Program, Minneapolis, Minnesota, told Reuters Health.

The results are based on an analysis of data from the Center for International Marrow and Blood Research. Included in the study were 373 recipients of autologous stem cells, 2,041 patients who received transplants from related donors, and 1,801 recipients of cells from unrelated donors. Standard criteria were used to classify the subjects as underweight, normal weight, overweight, or obese.

With autologous transplantation, no significant differences in treatment-related death, leukemia-free survival, relapse, or overall survival were noted between normal weight, overweight, and obese recipients.

With related donor transplantation, obese, but not overweight, status was associated with increased risks of death, treatment failure, and treatment-related death. Still, the elevated risks for these problems in obese patients were minor compared with the risks seen in underweight patients.

With unrelated donor transplantation, neither obesity nor overweight increased the risks of death, treatment failure, or treatment-related mortality. In fact, for relapse, obesity and overweight were actually associated with slightly reduced risks.

Obesity alone should not be considered a reason not to perform bone marrow transplants when this procedure is otherwise the best therapy, Navarro concluded.