Blood Test Detects Residual Disease For Adults With AML in Remission Prior to Bone Marrow Transplant

In 2020, there were more than 73,000 people living with acute myeloid leukemia (AML) in the United States. Approximately 31% of those with AML are estimated to survive 5 or more years after their diagnosis.¹ Although a bone marrow transplant may increase that 5-year survival rate, the efficacy of the procedure decreases for those who are in remission but still have residual traces of leukemia.

Therefore, detecting residual disease prior to bone marrow transplant can help identify patients at higher risk for both relapse and poorer overall survival. Although the presence of measurable residual disease (MRD) in adults in remission for AML has been associated with higher relapse rates, researchers have not come to a consensus on a standardized test.

In a recent study, a team of researchers² performed a retrospective observational study to determine whether DNA sequencing to recognize MRD in the blood of adults with AML in first remission before bone marrow transplant can identify if these patients are at an increased 3-year risk for relapse and survival, compared with those without these DNA variants.

They performed DNA sequencing on pretransplant blood from 1075 adults who had undergone their first bone marrow transplant during first remission for AML. The researchers screened for variants commonly associated with AML, including FLT3, NPM1, IDH1, IDH2, or KIT. All participants were part of one of 111 treatment sites from 2013 through 2019.

The researchers found that 822 patients had NPM1 and FLT3-ITD, which were the two most common mutations in AML that could be used to track residual leukemia. Of these 822 patients, 142 still had residual traces of these mutations after therapy, even after being classified as in remission.

These patients were found to have worse outcomes after transplant, including higher rates of relapse and decreased survival at 3 years. Indeed, 68% of patients with residual NPM1 and FLT3-ITD mutations had higher rates of relapse at 3 years and 39% survived after 3 years. Comparatively, 21% of adults without trace evidence of leukemia relapsed after 3 years and 63% survived for more than 3 years, according to the results of the study.

These results have major implications for how clinicians counsel their patients or tailor subsequent transplant strategies.

“Among patients with AML in first remission prior to allogeneic hematopoietic cell transplant, the persistence of FLT3 internal tandem duplication or NPM1 variants in the blood at an allele fraction of 0.01% or higher was associated with increased relapse and worse survival compared with those without these variants,” the researchers concluded.

Even with these results, the researchers noted that further study is needed to determine whether DNA-sequencing testing for residual variants can improve outcomes for patients with AML.

Reference

1. National Cancer Institute. Cancer stat facts: leukemia — acute myeloid leukemia (AML). Accessed May 11, 2023. https://seer.cancer.gov/statfacts/html/amyl.html.
2. Dillon LW, Gui G, Page KM, et al. DNA Sequencing to detect residual disease in adults with acute myeloid leukemia prior to hematopoietic cell transplant. JAMA. 2023;329(9):745-755. doi:10.1001/jama.2023.1363.