The use of stem cell transplantation for acute myeloid leukemia increased by about 55% worldwide from 2009 to 2016, according to new findings presented by Niederweiser et al at the 64th American Society of Hematology (ASH) Annual Meeting and Exposition (Abstract 3638). Although the largest increases were seen in lower- and middle-income countries, patients in these countries may still face the greatest barriers when it comes to accessing stem cell transplantation, the researchers revealed. Allogeneic stem cell transplants—the only curative therapy for the majority of patients with acute myeloid leukemia—accounted for the vast majority of the increase in stem cell transplants overall, whereas rates of autologous transplants allowing for the more intensive use of chemotherapy declined significantly.
Background
“The incidence of [acute myeloid leukemia] continues to rise, as does the use of stem cell transplantation, but this therapy is not being taken up equally across the world,” noted lead study author Molly Tokaz, MD, a hematology and oncology fellow at the Fred Hutchinson Cancer Center. “Utilization rates are lagging in lower resourced regions, and we’ve got a lot of ground to cover to get utilization where we want it. Since an allogeneic transplant is a curative treatment, this difference in uptake has profound implications for what kinds of outcomes we can expect for these patients.”
Study Methods and Results
In the new study, the researchers found that acute myeloid leukemia rates rose by about 2,000 diagnoses per year over the study period, reflecting an overall global uptick in incidence—with about 118,000 new diagnoses in 2016. The rate of stem cell transplantation increased by 55% overall from 2009 to 2016, but the use of transplantation as a percentage of patients with acute myeloid leukemia remained relatively low in many countries.
Even in well-resourced regions like North America and Europe, only about 18% to 20% of patients with acute myeloid leukemia received a stem cell transplant in 2016. While this was much higher than the 2% to 5% seen in regions such as Africa, the Middle East, and Latin America, it suggested that there may still be room for improvement in all regions of the world, according to the researchers.
They also discovered that more allografts were from unrelated donors in higher income countries compared with lower income countries—where donors were most often related to the recipient. These differences likely reflected the complex infrastructure required to match patients and facilitate transplants with unrelated donors.
The researchers concluded that although the study only used data through 2016, other ongoing studies suggested that the reported trends have continued in the intervening years—with many countries seeing an increase in the use of stem cell transplantation, but also significant gaps that remain between resource-rich and resource-poor regions.
Disclosure: For full disclosures of the study authors, visit ash.confex.com.
