Why Do Black Patients Fare Worse With Blood Cancer Than Whites?
A pair of studies shed new light on why a relatively rare blood cancer — acute myeloid leukemia (AML) — is more deadly among Black patients.
The takeaways: Where patients live and their access to quality health care matter. And even when Black people with AML have the same access to treatment as white patients, their survival is shorter — something genetic differences might explain.
Authors of the two studies recently discussed their findings at an online news briefing held by the American Society of Hematology.
"There is significant work to be done and sizable gaps to bridge," said Dr. Chancellor Donald, assistant professor of medicine, hematology and medical oncology at Tulane University School of Medicine in New Orleans, who led the briefing.
For the first study, researchers analyzed medical records from more than 800 people in Chicago with AML and found that Black patients from underprivileged communities had a 48% greater risk of dying from the disease compared to white patients.
Hispanic patients with AML who hailed from disadvantaged neighborhoods also a 20% greater risk of death compared to white patients, the findings showed.
Without accounting for neighborhood inequities, the gap in survival rates between Black and white AML patients narrowed, suggesting that a patient's ZIP code contributed to their chances of surviving the cancer.
The researchers said there are many potential explanations for the geographic disparity.
According to Dr. Bhavana Bhatnagar, an Ohio State University (OSU) cancer specialist and lead author of the second study, "Access can potentially be an issue, in terms of being able to get to tertiary care centers that have clinical trial availability and physicians who have disease-specific expertise in treating some of these rarer cancers. I think sometimes where these larger cancer centers are located can pose a barrier in terms of being able to access care."
Bhatnagar is a hematologist specializing in AML treatment at the OSU Comprehensive Cancer Center in Columbus.
In the second study, her team analyzed a nationwide cancer database. It revealed that younger Black patients with AML have a 27% higher chance of dying from the disease than younger white patients. Typically, younger patients have a greater opportunity for cure, Bhatnagar said.
But even when patients of both races received the same treatments, Black patients' outcomes were worse, clinical trial data showed.
"Even if they have the same access to treatment and the same rates of remission, Black patients have significantly shorter survival time compared to white patients," Bhatnagar said.
The researchers said genetic analysis revealed differences within the cancer cells of Black and white patients with AML.
Doctors now know that if a patient's leukemia cells have certain genetic mutations, their chance of survival is typically better. But Black patients were less likely to carry these mutations, and when they did, they did not produce the same favorable outcomes seen in white patients, the findings showed.
While treatment options and survival rates for AML patients as a whole have improved over time, the gap between Black and white patients' survival outcomes has actually widened, the researchers said.
The study showed that being Black is, in itself, a risk factor for worse outcomes from AML.
"We showed that, yes, these survival disparities exist," Bhatnagar said. "Clinical trial enrollment does not alleviate those disparities, and there are underlying genetic differences that do not necessarily portend the same prognostic value in younger black AML patients than they do in the AML population at large."
Moderator Donald commended the authors for digging in and getting closer to pinpointing some of the reasons for the health inequities.
"Race and ethnicity, among other factors, touch every facet of someone's life," he said. "If we are going to address health disparities, we have to identify where they exist. That takes calling out the different structures that may be propagating these problems."
To learn more about acute myeloid leukemia, visit the American Cancer Society.
SOURCE: American Society of Hematology, news briefing, Dec. 4, 2020