Racial and socioeconomic disparities in adult acute lymphoblastic leukemia: A multicenter cohort study Free

Over the past two decades, advances in the treatment of B-cell Acute Lymphoblastic Leukemia (B-ALL) have led to markedly improved patient outcomes. These improvements stem from better understanding of disease biology, integration of molecularly targeted therapies, incorporation of immunotherapy, and the adoption of measurable residual disease (MRD) as a key treatment milestone.Despite significant advancements, there is limited published data on differences in the utilization of immunotherapy, transplant, and survival outcomes in B-ALL among different ethnic groups and health care settings. While several studies have identified racial and ethnic disparities in childhood B-ALL, less is known about adult B-ALL outcomes across different health care centers.

This is a retrospective, multicenter cohort study designed to analyze clinical and demographic characteristics, treatment patterns, and outcomes in adult B-ALL patients treated from January 1, 2010, and November 30, 2023. Data were collected from the electronic health records (EHRs) of four major NCI designated cancer centers. Participating centers were the University of Texas Health Science Center at San Antonio, UT Southwestern Medical Center in Dallas, Baylor College of Medicine in Houston, and the University of Alabama at Birmingham. Descriptive statistics will summarize baseline characteristics. Kaplan-Meier curves estimated overall survival (OS), and comparative analyses were conducted across racial/ethnic groups by treatment uptake, transplant use, and survival.

413 patients were included for analysis. The median age was 45 years and 55% were male. The cohort included 47% Non-Hispanic White (NHW), 40% Hispanic, 10% African American, and 3% individuals of other racial backgrounds. Among the patients, 43% had commercial insurance, 14% were covered by Medicaid, 15% by Medicare, and 28% had other forms of insurance like county-sponsored programs or were uninsured. Forty-two percent of patients had Philadelphia chromosome–positive (Ph+) B-ALL, while 58% were Philadelphia chromosome–negative (Ph−). When compared to NHW, Hispanic patients were more likely to present with high-risk features (age > 35 years and white blood cells > 35,000 X 10⁹) (83.0% vs 69.9%, p = 0.0032). Poor cytogenetic risk was more commonly observed in Hispanic than NHW (28% vs 25.3%, p = 0.0073). Hispanic patients are significantly younger than NHW patients (mean age 38.2 vs. 51.7, p < 0.0001 for difference) and younger age is significantly associated with survival (p = 0.0006). HyperCVAD was the most common induction chemotherapy regimen for both Ph+ and Ph- patients and Dasatinib was the most used tyrosine kinase inhibitor used for Ph+ B-ALL (72%). The mean overall survival (mOS) was 46 months. There was clinically meaningful survival difference between Hispanic vs NHW. The mOS for Hispanic vs NHW was 52 months vs 88 months (p = 0.58). Commercially insured had a mOS of 78 months compared to 30.6 months with Medicaid (p = 0.006). Hispanics were less likely to have commercial insurance than NHW – 16% vs 64% (p = < 0.0001). 28% of the total population underwent Allogeneic stem cell transplant (Allo). 35% of the Ph+ and 24% of Ph- patients underwent Allo. Patients with commercial insurance were more likely to get Allo (p = < 0.001). There was a statistically significant difference between transplants rates in Hispanic (17%) vs NHW (36%).

This multicenter study of more than 400 B-ALL patients evaluate difference in disease biology, treatment patterns and survival based on race/ethnicity and insurance status. Hispanic patients were more likely to present at younger age and with high-risk disease features including poor cytogenic risk and were less likely to undergo allogeneic stem cell transplant as compared to NHW. Despite these statistically significant differences, we found no significant survival difference between the two different ethnic groups. Survival analysis showed that insurance status was associated with differences in overall survival and transplant rates. Therefore, survival differences between Hispanic and NHW patients are affected by competing factors of age and insurance in this study population (and likely other factors). It is important to consider associations of competing sociodemographic and clinical factors in understanding the effects of population characteristics on survival.