Abstract 4343: Retrospective study of incidence and survival for patients with hematological malignancies residing at the U.S./Mexico border
Authors: Bencomo Alfonso E. , Rubio Andres J. , Gonzalez Mayra A. , Olivas Idaly M. , Lara Joshua J. , Ghimire Kiran , Padilla Osvaldo , Padilla Angelica , Hakim Nawar , Orazi Attilio , Corral Javier , Philipovskiy Alexander , Gaur Sumit , Eiring Anna M. 
Published: September 2020

Introduction: Hispanics represent the largest minority group in the United States (U.S.), with 57.5 million individuals. The majority of Hispanics in the U.S. reside in the Southwest region, and &gt;11 million live in the state of Texas. Health disparities for Hispanic cancer patients have previously been linked to disproportionate poverty and other barriers to optimal healthcare. In the case of acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL), Hispanics were found to be diagnosed at a younger age and have worse overall survival (OS) compared with non-Hispanic whites (NHWs) (ACS Cancer Facts & Figures for Hispanics/Latinos 2018-2020). However, little is known about incidence and survival for Hispanic blood cancer patients residing at the U.S./Mexico border.

Methods: We retrospectively reviewed data from the Texas Cancer Registry for hematologic malignancies diagnosed in the state of Texas between 1995 and 2016, focusing our analysis on chronic and acute leukemia's (both myeloid and lymphoid), myelodysplastic syndrome (MDS), and myeloproliferative neoplasms (MPNs). Survival for Hispanic and NHW groups was compared using the log-rank test, and Cox regression analyses adjusting for age and diagnosis. Differences in age at diagnosis were evaluated using t-tests and generalized linear models. Research was conducted according to a local IRB-approved protocol in accordance with the Declaration of Helsinki.

Results: Of the 69,941 cases of hematologic malignancies with available information throughout the state of Texas, 18.29% identified as Hispanic. We found that Hispanic patients were diagnosed at a significantly younger age in all diseases analyzed (p&lt;0.0001). Surprisingly, in unadjusted analyses, Hispanics had significantly better OS than NHWs diagnosed with myeloid malignancies (p&lt;0.0001), but no significant differences for patients with other types of leukemia. After adjusting for age, there was a clear disparity in OS for Hispanic versus NHW patients with ALL (p&lt;0.0001) and acute promyelocytic leukemia (APL, p=0.03), with no significant differences in other diseases. We also compared Hispanic patients diagnosed in El Paso versus Hispanics from the rest of Texas. Hispanics in El Paso had a significant reduction in OS compared to Hispanics in other areas of Texas for ALL (p=0.0164), AML (p&lt;0.0001), and chronic myeloid leukemia (CML, p=0.016).

Conclusions: Hispanics are diagnosed at a significantly younger age than NHWs in all blood malignancies analyzed. Hispanic patients with AML, MDS, and CML had significantly better OS compared to NHWs in unadjusted analyses, which could be explained by the reduced age of diagnosis. Hispanics with ALL, AML, or CML diagnosed near the U.S./Mexico border demonstrate worse OS compared with Hispanics diagnosed in other areas of Texas. In age-adjusted analyses, Hispanic patients with ALL or APL have a worse OS compared with NHWs. There appears to be evidence that disparities in outcome by ethnicity may be different in El Paso compared with the rest of Texas.

Future Directions: Our data demonstrates blood cancer disparities present in our region. Further study is required to identify factors responsible for the disparity in OS, and to identify ways to address it.

Citation Format: Alfonso E. Bencomo, Andres J. Rubio, Mayra A. Gonzalez, Idaly M. Olivas, Joshua J. Lara, Kiran Ghimire, Osvaldo Padilla, Angelica Padilla, Nawar Hakim, Attilio Orazi, Javier Corral, Alexander Philipovskiy, Sumit Gaur, Anna M. Eiring. Retrospective study of incidence and survival for patients with hematological malignancies residing at the U.S./Mexico border [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4343.