Introduction: Mature T- and NK-cell neoplasms (MTNKN) exhibit a significantly higher incidence in LATAM compared to Western Europe and North America. This disparity is partly attributed to a high prevalence of EBV and HTLV-1. Despite the elevated burden of MTNKN in these regions, comprehensive data on non-Hodgkin lymphomas (NHL) remain scarce. We conducted the first population-based registry to analyze the incidence of MTNKN in Peru, focusing on regional differences and migration patterns.
Methods: The study included patients with newly diagnosed MTNKN from 2010 to 2020. We calculated ASIR, SIR, and performed spatial analysis and clustering using both birthplace and place of residence, and an Empirical Bayes Poisson-Gamma mixture model.
Results: A total of 1,086 newly diagnosed MTNKN cases were identified, accounting for 18.7% of all NHL cases. The cases were stratified by geographic origin as coastal (57%), Andean (38%), and Amazonian (5%). Among aggressive MTNKN cases, 34% were associated with HTLV-1, and 21% with EBV (21%). The median age at diagnosis was 37 years for Amazonian, 50 years for coastal, and 55 years for Andean (p < 0.001). The national ASIR of MTNKN was 3.70 per 100,000 population (95% CI: 3.48–3.93). Spatial analysis revealed a well-defined cluster in the central-south Andean region when assessed by birthplace, encompassing Ayacucho (p = 0.0002), Apurimac (p = 0.006), and Huancavelica (p = 0.047). In a multivariate analysis, Quechua as a mother tongue emerged as the only independent predictor of increased incidence risk.
Conclusion: Our findings underscore that virus-related T-cell lymphomas are the most common MTNKN subtypes in Peru, with significant clustering observed in Quechua-speaking regions.
