Epstein-Barr virus in pyothorax-associated pleural lymphoma.

Pleural B-cell lymphoma was found in five patients with a history of pyothorax that was the sequelae of tuberculosis 35 to 47 years previously. Epstein-Barr virus (EBV) DNA was detected in all five pleural tumors by polymerase chain reaction and Southern blot hybridization. The lymphoma cells were shown to express the latent membrane protein-1 and the EBV-encoded nuclear antigen-2 by immunocytochemistry and EBV-encoded small RNA by in situ hybridization. Three cases were shown to be EBV subtype A, whereas the remaining two were subtype B, as determined by differences in the EBV-encoded nuclear antigen-2 nucleotide sequence. The patients also had high titers of antibodies against EBV. These findings suggest that EBV is causally associated with the pleural lymphomas that originate at the site of chronic inflammation and fibrosis with a latent period of more than 40 years.