Lymphomatoid granulomatosis is currently classified as part of a spect
rum of angiocentric immunoproliferative lesions. These were initially
thought to be of T-cell phenotype, but recent papers have shown that s
ome cases are B-cell proliferations, sometimes associated with Epstein
-Barr virus infection. We reviewed the clinicopathological features of
16 patients with pulmonary lymphomatoid granulomatosis, using immunoh
istochemistry to assess the phenotype of the infiltrate, the polymeras
e chain reaction to look for immunoglobulin heavy chain and T-cell rec
eptor gene rearrangements, and in-situ-hybridization to look for Epste
in-Barr virus infection, In seven of seven cases the atypical lymphoid
population was of B-cell phenotype, with four cases showing evidence
of either monoclonality or oligoclonality, All seven cases, including
those that lacked unequivocal proof of malignancy, behaved aggressivel
y. Epstein-Barr virus RNA was detected in four cases, We conclude that
some cases of lymphomatoid granulomatosis are B-cell lymphomas, somet
imes associated with Epstein-Barr virus infection.