The younger Black patients with acute myeloid leukemia (AML) had “alarmingly high” early death rates within the first 30 days of study enrollment, indicating possible delays in diagnosis and care, according to research results reported in the journal Blood Advances.
A team of researchers is calling for systemic changes in patient care after their study showed worse outcomes among Black patients with acute myeloid leukemia (AML).
Black patients with AML had worse outcomes — especially those ages 18 to 29 years old, who had a higher early death rate — than White patients, according to the research published in the journal Blood Advances.
Karilyn T. Larkin, M.D., a hematologist and clinical instructor at Ohio State University’s James Cancer Hospital and Solove Research Institute, and colleagues said they knew that survival of patients with AML is inversely associated with age. Less was known about the association between race and outcomes among young adults, 18 to 39.
To that end, they compared the survival of 89 non-Hispanic Black and 566 non-Hispanic White young patients with AML, using data from a National Cancer Institute clinical trial group.
They found that Black patients had decreased overall survival of 22% over 5 years versus 51% for White. Black patients also had worse outcomes (16% compared to 3% for White) and lower complete remission rate (66% compared 83% for whites).
Younger Black patients had the worst outcomes, Larkin wrote. Black patients, ages 18 to 29, with non–core-binding factor (CBF)-AML had worse overall survival rates than White patients (12% versus 44%) including patients with cytogenetically normal AML (13% versus 50%).
The survival disparity occurred exclusively among the younger patients, ages 18 to 29 years, Larkin and her colleagues noted, whereas Black and White patients, ages 30 to 39, had similar outcomes.
The younger AML Black patients had “alarmingly high” early death rates within the first 30 days of study enrollment, indicating possible delays in diagnosis and care, and a low complete remission rate of only 66%, which suggests “inherently different responses to induction therapy,” according to Larkin.
“These features contributed to these very young adult Black patients having a median survival nearly nine years shorter than White patients in the same age group,” Larkin added. “Higher early death rates suggest a delay in diagnosis and treatment, calling for systematic changes to patient care.”
The researchers found different genetic features in Black patients, including lower frequencies of normal karyotypes (the number and visual characteristics of chromosomes in the cell), NPM1 (the gene that provides instructions for making the protein nucleophosminand biallelic), and CEBPA (transcription factor CCAAT/enhancer binding protein α) mutations. They also discovered higher frequencies of CBF rearrangements and other genetic mutations in Black patients.
“Our pilot exome-sequencing data indicate that common AML mutations are also found in Black patients. However, almost one-third of the detected variants were found in genes thus far not associated with AML, indicating the need for larger studies in this population to assess frequencies of these gene mutations and their associations with diseases,” Larkin wrote.
In addition, Black patients’ response rates to induction chemotherapy and leukemic clone persistence suggest a need for different treatment intensities and/or modalities, according to Larkin and the other researchers.
Despite inferior survival of Black patients with CBF-AML compared with Whites, the prognosis of Black patients with CBF-AML was still relatively favorable, because the five-year overall survival (OS) rate of 18- to 29-year-old Black patients with non–CBF-AML was only 12% versus 54% in Black patients with CBF-AML, wrote Larkin and her colleagues.
The researchers found that about 40% of young adult Black patients harbor a CBF-AML–defining chromosomal abnormality, “indicative of a distinct disease biology in this population that requires further attention and exploration,” Larkin wrote.
The study is limited by relatively small sample sizes of the particular molecular subgroups.
“Furthermore, in view of the observed differences in the early death rates, the incompleteness of records with causes of patients’ early death and sociodemographic features precluded more in-depth analyses that could potentially help explain this alarming disparity, thus making further large studies necessary,” wrote Larkin and her colleagues.