[Thymic mucosa-associated lymphoid tissue (MALT) lymphoma developing during long-term follow-up for Sjögren's syndrome and idiopathic thrombocytopenic purpura;report of a case].

Mucosa-associated lymphoid tissue (MALT) lymphoma is a rare type of lymphoma that arises in small CD20-positive lymphocytes. We encountered a case of thymic MALT lymphoma treated with surgical intervention during long-term follow-up for Sjögren's syndrome and idiopathic thrombocytopenic purpura (ITP). Although symptomatic remission of Sjögren's syndrome and ITP had already been achieved, the levels of anti-SSA and anti-SSB antibodies remained high. Chronic stimulation by these antibodies may contribute to the development of MALT lymphoma. A careful follow-up may be indicated for this case with a complex immunological background.