Angioimmunoblastic T-cell lymphoma: a relatively common type of T-cell lymphoma in Sjögren's syndrome.

An increased risk of developing lymphoma has been indicated in Sjögren's syndrome (SS), and the lymphomas in SS are usually B-cell type in origin. Interestingly, despite the rather low frequency of T-cell lymphoma in SS, angioimmunoblastic T-cell lymphoma (AILD) constitute the majority of T-cell lymphomas associated with SS. To the best of our knowledge, including our case, at least 11 out of 23 (48%) cases of T-cell lymphoma reported in association with SS, were AILD. The fact that the development of B-cell lymphoma in SS is much more frequent than that of T-cell lymphoma, might be explained by differences in the situation between B and T cells, although the exact mechanism still remains uncertain.