B cell lymphoma with lung involvement: what is it about?

Primary lymphoma of the lung or pleural is a very rare condition. Due to the outdated literature data, the approximate occurrence of primary and secondary lung and/or pleural involvement according to the most common B cell lymphoma entities is unknown. To answer this open question in Austria, we screened the Tyrolean registry for B cell non-Hodgkin's lymphomas regarding primary and secondary lung involvement. Of 854 patients affected by B cell lymphoma, 7.5% had lung/pleural disease. This organ was the primary site in only 0.7%, while a secondary involvement was registered in 6.8%. Most of them were affected by diffuse large B cell lymphoma (DLBCL; 29/368, 8%) followed by follicular lymphoma (7/188, 4%), mantle cell lymphoma (7/57, 12%), mucosa-associated tissue lymphoma (10/37, 27%), posttransplant lymphoproliferative disease (6/24, 25%), Burkitt lymphoma (3/19, 16%), other lymphomas (1/32, 3%) and Richter transformation (1/11, 9%). Moreover, primary lung/pleural lymphoma is one of the rarest neoplasias affecting the lung, accounting for only 0.4% of cases. Lung/pleural involvement is a very rare condition among B cell lymphomas since it mainly occurs in the setting of a generalized disease. A large majority of patients with secondary organ involvement are affected by DLBCL and have similar clinical features at diagnosis to others with advanced-stage disease.