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Lymphomas involving the pleura: a clinicopathologic study of 34 cases diagnosed by pleural biopsy.

CONTEXT
Pleural involvement by lymphoma is relatively common. However, there are very few clinicopathologic studies reported in the literature of lymphomas involving the pleura.


OBJECTIVE
To characterize the clinicopathologic features of lymphomas involving the pleura.


DESIGN
We reviewed the clinicopathologic features of 34 patients with lymphoma involving the pleura proven by biopsy and classified these neoplasms using the World Health Organization classification.


RESULTS
There were 22 men and 12 women, with an average age of 62 years (range, 22-82 years). Nine (26.5%) patients had pleural involvement as the only site of disease, 22 (64.7%) had other sites of involvement, and 3 (8.8%) had inadequate staging data. Eighteen (56.2%) of 32 patients with adequate clinical data had a history of lymphoma (including 3 patients with pleural involvement as the only disease site). In 29 (85.3%) cases, a specific diagnosis according to the World Health Organization classification could be made: 17 (58.6%) diffuse large B-cell lymphoma, 5 (17.2%) follicular lymphoma (including a case with areas of diffuse large B-cell lymphoma), 2 (6.9%) small lymphocytic lymphomas/chronic lymphocytic leukemia, 2 (6.9%) precursor T-cell lymphoblastic lymphoma/leukemia, 1 (3.4%) mantle cell lymphoma, 1 (3.4%) posttransplant lymphoproliferative disorder, and 1 (3.4%) classical Hodgkin lymphoma. The other 5 cases were B-cell lymphomas that could not be further classified. Cytologic examination of pleural fluid was performed in 15 cases and was positive for lymphoma in 8 (53.3%) cases.


CONCLUSIONS
Most patients with lymphoma involving the pleura have simultaneous evidence of systemic involvement. The most frequent type is diffuse large B-cell lymphoma, followed by follicular lymphoma. Cytologic examination can have negative results in patients with pleural involvement by lymphoma.