A case of thymic malt lymphoma with sjögren's syndrome

Abstract

Thymic MALT lymphoma is rare. Only approximately 30 cases have been reported in Japan. We treated a patient who developed thymic MALT lymphoma during Sjögren's syndrome treatment. We report this case along with a discussion of the relevant literature.
The patient was a 47-year-old woman. She had been treated as an outpatient for Sjögren's syndrome since January 1998. In February 2002, she stopped treatment for personal reasons. In June 2004, she presented with recurrent arthralgia affecting multiple joints. The chest CT scan revealed a mediastinal tumor. In August 2004, a thymectomy was performed, since a thymic malignant lymphoma or a multilocular thymic cyst was suspected.
Postoperatively, on pathology, infiltration of tumorous lymphocytes into Hassall's body (lymphoepithelial lesions) was noted. The cells were positive for CD20 on immunostaining, both κ and λ globulin chains were detected. Therefore, MALT lymphoma of thymic origin was diagnosed. Adjuvant chemotherapy was given after surgery. The patient has been doing well and has not had any reccurence during 4 years of follow-up.