Mucosal intra-epithelial lymphocytes in enteropathy-associated T-cell lymphoma, ulcerative jejunitis, and refractory celiac disease constitute a neoplastic population.

Loss of response to a gluten-free diet (refractory sprue) and ulcerative jejunitis are complications of celiac disease that may progress to enteropathy-associated T-cell lymphoma (EATL). Both conditions are characterized by the presence of a nonlymphomatous monoclonal T-cell population in the enteropathic mucosa. In EATL, a similar monoclonal population that shows clonal identity with the lymphoma itself is also present in the enteropathic mucosa. In this study we show that in all three circumstances the monoclonal T-cell population is constituted by cytologically normal, noninvasive intraepithelial T lymphocytes that share an identical aberrant immunophenotype with EATL. Patients with refractory sprue and/or ulcerative jejunitis are, therefore, suffering from a neoplastic T-cell disorder for which hematological treatment strategies need to be devised.