Racial disparities in survival of adult T-cell leukemia/lymphoma patients in the United States: A SEER database analysis.

Abstract

e16503 Background: Adult T cell Leukemia/Lymphoma (ATL) is an aggressive lymphoproliferative disorder etiologically linked to Human T cell Lymphotropic Virus -1 (HTLV-1). HTLV-1 infection is endemic in areas of Japan, the Caribbean, South America, and Africa. ATL runs a very aggressive clinical course. It is a rare malignancy in the United States (US), and epidemiologic data are limited. We undertook a Surveillance Epidemiology and End Results (SEER) based database analysis to identify survival data of ATL patients (pts) with emphasis on race and ethnicity. Methods: We used the SEER 17 Registry data (1973-2008) for pts with a confirmed diagnosis of ATL. ICD-O-3 code 9827/3 was used to identify pts with ATL. The following exclusion criteria were used: diagnosis at death certificate or autopsy, no follow-up records, diagnosis of second malignancies or lack of documentation of sex or age at diagnosis. The Kaplan Meier method was used to evaluate survival in different races. Statistical tests were done utilizing R statistical software. Results: 272 patients were included in the final analysis (126 females; 146 males). Pts were stratified by race: White (155), Black (80), Other (33), Unknown (4). Median age (yr) of diagnosis in Blacks (51.5) was lower than in Whites (65) and other races (65). Average age of diagnosis in Blacks was significantly lower compared to Whites (p=0.002) and non-Blacks (p=0.0008). Survival analysis of the study group showed a median overall survival (OS) of 13 mo (95%CI 10-16). Whites had a higher median OS (21 mo) compared to blacks (5 mo); the difference in survival was strongly significant (Log-rank p-value < 0.001). Differences in survival between blacks or whites compared to other ethnic and unknown racial groups (n=37) were not statistically significant. Conclusions: ATL is a rare malignancy with poor prognosis in the US. Epidemiologic data on survival are limited. Blacks tend to have an earlier onset of disease and a poor prognosis compared to whites. The reasons for this aggressive course and earlier age of diagnosis in blacks are unknown.