A contemporary national population-based analysis of demographics and outcomes of Hispanics with adult T-cell leukemia/lymphoma in the US.

Abstract

e18771 Background: Adult T-cell Leukemia/Lymphoma (ATL) is a malignancy caused by the human T-cell leukemia virus type I with heterogenous clinical course (Blood Adv PMID29545256 J Clin Exp Hematop PMID34937829). There are endemic regions, but emigration has increased its incidence in the United States (US) (Hematol Oncol Clin North AmPMID2834087). There is a need to recognize trends and ethnic patterns to better understand this malignancy (J Oncol Pract PMID28796966 Blood Adv PMID29545256). This is the first national population-based analysis evaluating ethnic differences for HI diagnosed with ATL in the US. Methods: Data were analyzed on ATL patients in the US reported to the Surveillance, Epidemiology, and End Results (SEER) database between 2000-2018. Demographic, clinical and survival patterns were analyzed. Kaplan-Meier and Cox regression analyses were used when appropriate. Multivariate analysis and propensity score matching were performed with adjustment for age, stage and B-symptoms. Results: 598 patients (HI=65, NH=533) were diagnosed with ATL. Male sex predominated in in both. HI were diagnosed at a younger median age, 52 years (y) vs 63y for NH [p<0.001]. Most of HI presented in the age bracket of 40-60y, while NH were identified between 60-80y [p <0.001]. Regarding race, most of HI and NH were whites 82% vs 52% respectively, however, for NH Blacks and Asian/Pacific Islander were noted to be representative in the sample [p <0.001]. The majority of HI were diagnosed between 2010-2014, however for NH, same incidence was reported from 2005-2009 and 2010-2014 [p = 0.107]. For both group the presence of B symptoms was predominantly unknown. The median survival for HI was 1.5y vs 0.8y for NH. The survival probability at 2, 5 and 10y for HI corresponded to 0.474, 0.341 and 0.238, while for NH it was 0.347, 0.244 and 0.153, respectively. The OS probability at 10y had no statistically significant difference but a tendency favoring HI [p = 0.053]. On multivariate analysis, when adjusted for age, those patients who were older than 80y and between 60-80 y, had worse OS compared to those younger than 60y, with Hazard Ratio of 3.9 (95% CI: 2.7 – 5.6) and 1.7 (95% CI: 1.2 – 2.2), respectively. Conclusions: This national population-based study identified similar OS in HI diagnosed with ATL in the US. The median survival time was noted to be higher for HI and the OS had a tendency favoring this group; however, findings are not yet significant. This association should be further analyzed as there may be unique oncologic response in this ethnic minority. HI may have remarkable immunologic reaction to infection due to oncogenic viruses plus the creation of a distinct tumor microenvironment. Recognizing clinical trends and identifying genetic predictors may assist in constructing more accurate prognostic indices to deliver targeted therapy.