Racial disparities in survival trends in burkitt lymphoma in the CAR-T cell therapy era vs pre-CAR-T cell therapy era in the United States: A population-based study

Abstract

Abstract Background: Burkitt lymphoma (BL) is an uncommon and aggressive B cell non-Hodgkin lymphoma (NHL) that develops from mature, germinal, or post-germinal center B cells. Dysregulation of the proto-oncogene MYC, which is frequently brought on by a normal chromosomal translocation, is its defining feature. Chimeric Antigen Receptors (CARs) are novel engineered proteins that alter T-cell antigen specificity. The Food and Drug Administration (FDA) approved the first CAR-T therapeutic agents in 2017. CAR-T cell therapy is used for relapsing and refractory (r/r) Burkitt Lymphomas. Previous population-based study showed improvement in overall survival (OS) with rituximab for the treatment of Burkitt lymphoma. Currently, there is limited data on survival after the introduction of CAR-T cell therapy at the population level. In our study, we hypothesized that improvements in survival have been made in recent years with the introduction of CAR-T cell therapy for the treatment of r/r Burkitt lymphoma. Methods: We used the Surveillance, Epidemiology, and End-Results (SEER) research program data to conduct a retrospective study of patients diagnosed with Burkitt Lymphoma between 2012-2021. This period was divided into two cohorts: pre-CAR-T approval (2012-2016) and post-CAR-T approval era (2017-2021). Statistical analysis was performed using SPSS. Patient characteristics were expressed as number (N) and percentages (%). The Kaplan-Meier method was used to compare the OS of both eras. OS was defined as the time from diagnosis to death. Cox proportional hazard regression was used to compare both cohorts and expressed as hazard ratios. A p-value ≤0.05 was considered statistically significant. Results: We identified patients with Burkitt lymphoma between 2012 and 2021; a total of 2,290 patients were diagnosed, with males being more predominant (1,731 patients, 75.6%) compared to females (559 patients, 24.4%). Majority were Non-Hispanic White (1,312; 57.3%), followed by Hispanic (512; 22.4%), Non-Hispanic Asian or Pacific Islander (228; 10.0%), Non-Hispanic Black (204; 8.9%), Non-Hispanic American Indian/Alaska Native (22; 1.0%), and Non-Hispanic patients of unknown race (12; 0.5%). OS before and after CAR-T cell approval (before 2017 and post 2017) did not show a statistically significant difference (log-rank p=0.41). Additionally, there was no statistically significant difference by gender (log-rank p=0.63). However, a significant disparity in survival was observed across racial and ethnic groups (log-rank p = 0.002). Only the Non-Hispanic Black patients reached the median, while other races did not. Conclusion: In our population-based study of patients diagnosed with Burkitt lymphoma between 2012 and 2021, there was no statistically significant difference in OS before and after the approval of CAR-T cell therapy. Survival outcomes were also not influenced by gender. However, significant racial and ethnic disparities were observed, with Non-Hispanic Black patients experiencing the lowest OS. A limitation of our study is its smaller population. This study requires further investigation into racial disparities.