Malignant lymphomas more common in celiac disease patients

A new population-based analysis has found that individuals with celiac disease are at increased risk of B-cell and T-cell lymphoma that may occur outside of the intestines.

While celiac disease has long been known to be linked with enteropathy-type T cell lymphoma (ETTL), there has been no investigation into whether patients with the condition might be at greater risk of other, more common lymphoma types, Dr. Karin Ekstrom Smedby of the Karolinska Institute in Stockholm and colleagues note in their paper, published in the January issue of the journal Gut.To investigate, the researchers studied 56 cases of lymphoma that occurred among 11,650 patients hospitalized with celiac disease, and compared the rate with that seen in the general population.Patients with celiac disease were at greater risk of B-cell non-Hodgkin lymphoma (NHL) and lymphomas of non-intestinal origin, the researchers found. Their risk of any type of NHL was nearly seven-fold greater than that of the general population, while they showed no increased risk of Hodgkin’s lymphoma.The researchers also noted a “remarkable aggregation” of autoimmune/inflammatory conditions, female sex, celiac disease and B cell lymphoma. Three in four patients with B cell NHL were women, and women accounted for two thirds of non-intestinal lymphomas. Forty-four percent of patients with B cell NHL also had autoimmune and inflammatory conditions, and 5% of patients with T cell NHL did.”This observed aggregation is supportive of our overall findings that celiac disease, as an autoimmune disorder, is associated with other autoimmune disorders and with B-cell lymphomas (not only with rare T-cell lymphomas of the intestine),” Dr. Smedby told Reuters Health.She noted that autoimmune conditions are known to be more common among women, while B-cell lymphomas also have been tied to certain types of autoimmune disease. “The observed aggregation could indicate a more general link between autoimmunity and B-cell lymphomas, although the mechanisms behind such an association remain unknown. A possible mechanism could be constant immune activation and could perhaps then apply to other chronic inflammatory disorders as well.”The mechanisms behind the association with B-cell lymphoma and celiac disease could be different from those involved in ETTL and celiac disease, she added. “The well-known association with ETTL may be due to local intestinal effects related to gluten-induced mucosal changes and successive malignant transformation of T-cell clones.””An association with non-intestinal lymphomas and B-cell lymphomas may involve systemic mechanisms related to autoimmunity, such as chronic immune stimulation, immune dysfunction, or other mechanisms.”While the clinical implications of the findings should not be overinterpreted, Dr. Smedby said, “local lymphoid swelling or not otherwise explained general decline of a patient’s well-being, knowledge of increased risks for more common lymphoma types may decrease time to lymphoma diagnosis and improve survival.”(Source: Gut, Reuters Health, January 2005)