Thymic and pulmonary mucosa-associated lymphoid tissue lymphomas.

A 52-year-old woman with no history of autoimmune disease was found to have a mediastinal tumor and focal airspace opacity in the right lung. Tissue diagnosis was obtained by resection of the mediastinal tumor and open fine needle aspiration of the right pulmonary tissue through a median sternotomy. Histopathologic examination and immunohistochemistry of the thymus tumor and cytologic analysis of the pulmonary tissue were both consistent with mucosa-associated lymphoid tissue (MALT) lymphoma. This case suggests that multiorgan MALT lymphoma can also develop in the absence of an autoimmune disease such as Sjogren's syndrome.