Increasing incidence of enteropathy-associated T-cell lymphoma in the United States, 1973-2008.

BACKGROUND: Enteropathy-associated T-cell lymphoma (EATL) is a rare lymphoma subtype that is strongly associated with celiac disease (CD), an autoimmune disease triggered by the ingestion of gluten. Because CD rates are increasing in the United States, the authors sought to determine whether the incidence rates of EATL also are increasing.
METHODS: The authors identified patients with primary, pathologically confirmed lymphoma in the Surveillance, Epidemiology, and End Results database registries from 1973 to 2008. To ensure capture of all cases of EATL, the following lymphoma subtypes, limited to the small bowel, were included: non-Hodgkin lymphoma not otherwise specified (NOS) T-cell, peripheral T-cell lymphoma NOS, and enteropathy type T-cell lymphoma, and their age-adjusted and sex-adjusted incidence rates were calculated over time. Survival was estimated using Kaplan-Meier curves.
RESULTS: In total, the authors identified 161 small bowel lymphomas that were diagnosed between 1973 and 2008. The overall age-adjusted and sex-adjusted annual incidence for all bowel lymphomas was 0.016 per 100,000 population, which increased over the study period from 0.006 to 0.024 per 100,000 population. These tumors were most common in men (age-adjusted incidence rate, 0.021 per 100,000) with the highest incidence rate in Hispanics (age-adjusted incidence rate, 0.033 per 100,000). The median overall survival was 7 months. There was no difference in survival by race/ethnicity (P = .09) or sex (P = .06).
CONCLUSIONS: The current results indicated a significant increase in the incidence of EATL in the United States, which may reflect the increasing seroprevalence of CD and better recognition of rare types of T-cell lymphomas. The incidence may continue to rise given the large ratio of undiagnosed-to-diagnosed individuals with CD in the United States.