In a multiethnic study of patients with acute lymphoblastic leukemia (ALL), many factors appeared associated with relapse risk. Most cases of relapse occurred in patients who had minimal residual disease (MRD) negativity, and Latino patients with MRD negativity were more likely to undergo relapse than non-Latino White patients.1,2 Results of this study were presented at the AACR Annual Meeting 2022 by Pagna Sok, MPH, of Baylor College of Medicine in Houston, Texas, and colleagues.1
The researchers noted that a risk factor for relapse in ALL is Latino ethnicity, and relapse with ALL is associated with poor outcomes. According to the researchers, the strongest prognostic factor for relapse of ALL is the presence of MRD at the end of induction treatment, but MRD negativity is found in approximately half of all children experiencing relapse. The researchers undertook this analysis with an aim of exploring risk factors for relapse in this patient population.
The study was based on data from patients with ALL from the Reducing Ethnic Disparities in Acute Leukemia (REDIAL) Consortium, which includes 6 pediatric centers throughout the southwestern US. Included patients were 1 to 23 years of age at the time of ALL diagnosis. The researchers considered multiple demographic and clinical factors in their analysis of possible risk factors for relapse.
A total of 1710 patients with ALL were identified in the analysis, and they had a median age of 5 years at ALL diagnosis. More than half (60.1%) of patients in the analysis were Latino. There were 379 patients with MRD positivity, among whom 19.5% experienced relapse. The remaining 1233 patients had MRD negativity, and 11.2% of these patients showed relapse (P <.0001). Overall, approximately 65% of relapses occurred in patients with MRD negativity.
Adjusted analyses revealed a few factors that appeared associated with relapse. Higher relapse risk was seen with older age at diagnosis (hazard ratio [HR], 1.98; 95% CI, 1.19-3.29 for younger than 15 versus 1-5 years of age), MRD positivity (HR, 1.72; 95% CI, 1.26-2.36), and National Cancer Institute (NCI) high-risk status (HR, 1.74; 95% CI, 1.20-2.52).1 However, enrollment on a clinical trial was associated with a lower risk of relapse (HR, 0.76; 95% CI, 0.57-0.99).
In patients with MRD positivity, there was a lower risk of relapse among Latino patients (HR, 0.60; 95% CI, 0.33-0.99) in comparison with non-Latino White patients. Latino patients who were MRD negative, however, had greater relapse risk (HR, 1.68; 95% CI, 1.09-2.59).
The researchers concluded that most cases of relapse in this population occurred in patients who had reached MRD negativity, and multiple factors appeared significantly associated with relapse risk.
“We were surprised that Latinos who were MRD-negative were more likely to experience ALL relapse compared to non-Latino whites,” lead study author Phillip Lupo, PhD, said in a press release associated with the group’s presentation. “This highlights the need to identify factors that contribute to relapse among Latinos so that we can achieve better outcomes for children of all racial and ethnic backgrounds.”2
- Sok P, Brown AL, Taylor OA, et al. Disparities in relapse among a large multi-ethnic population of children diagnosed with acute lymphoblastic leukemia (ALL): a report from the Reducing Ethnic Disparities in Acute Leukemia (REDIAL) Consortium. Presented at AACR 2022; April 8-13, 2022. Abstract 3633.
- Some Latino children diagnosed with acute lymphoblastic leukemia face higher risk of relapse compared to non-Latino White children. News release. AACR; April 12, 2022.
This article originally appeared on Hematology Advisor