Prevalence and survival outcomes of adult T-cell leukemia/lymphoma in Latin America: A multicenter cohort study and recommendations to improve diagnosis and outcomes

Abstract

Background: Although adult T-cell leukemia/lymphoma (ATL) has a higher burden in Latin America compared to North American or European countries, few studies have described the outcomes of this disease. We estimated the hospital-based prevalence and overall survival (OS) of ATL.

Methods: We conducted a cohort study among patients aged ≥ 18 years with pathologically diagnosed mature T-cell lymphoma across 11 Latin American countries from 2000 to 2023 by pooling data from 3 hospital-based registries. We used the Kaplan-Meier method to estimate survival outcomes.

Results: Among 1963 patients with mature T-cell lymphoma, the pooled prevalence of ATL was 17 % (n = 329; 95 % confidence interval [CI]=15-18 %), with the highest observed in Peru (n = 158; 38 %, 95 % CI=33-43 %) and Colombia (n = 17; 29 %, 95 % CI=18-41 %). Over time, ATL cases only increased significantly in Peru, from 14 % in 2000-2004 to 58 % in 2019-2023 (P_trend<0.001). With a median follow-up of 37 months (95 % CI=30-54 months), the 3-year OS of ATL was 25 % (95 % CI=20-32 %), and the median OS was 9 months (95 % CI=8-12 months). OS did not differ across countries (range 19-47 %, P = 0.210). Patients with lymphomatous ATL had worse outcomes than those with PTCL-NOS only in Peru (P_{heterogeneity}=0.029).

Conclusion: Our findings indicate a higher ATL prevalence in Latin America than previously reported in North America or Europe, likely due to differences in HTLV-1 endemicity and diagnostic practices. The similar and poor survival rates across countries underscore the need for targeted interventions to improve patient outcomes. We propose expert-based research priorities and suggest further epidemiological validation studies.

Keywords: Adult T-cell leukemia-lymphoma; Human lymphotropic virus type 1; Latin America; Prevalence; Survival.