Ag. Nicholson et al., PULMONARY B-CELL NON-HODGKINS-LYMPHOMAS - THE VALUE OF IMMUNOHISTOCHEMISTRY AND GENE ANALYSIS IN DIAGNOSIS, Histopathology, 26(5), 1995, pp. 395-403
We reviewed 45 pulmonary B-cell non-Hodgkin's lymphomas to determine w
hether their morphology and immunohistochemical features were those of
lymphomas arising from mucosa-associated lymphoid tissue (MALT), as d
escribed in other sites, The polymerase chain reaction was used to pro
vide further information on clonality, We found that these lymphomas i
nfiltrate the pulmonary interstitium along bronchovascular bundles and
interlobular septa, subsequently spilling out into airspaces and fina
lly destroying the alveolar architecture of the lung. Central hyaline
sclerosis and vascular infiltration were common features. All lymphoma
s stained CD20 positive and were accompanied by variable numbers of re
active CD3 positive T-cells, Cytokeratin staining with CAM 5.2 was use
ful in identifying lymphoepithelial lesions. CD21 staining of follicul
ar dendritic cells revealed germinal centres where they were not recog
nizable on H and E staining. The polymerase chain reaction was perform
ed on paraffin tissue from 28 patients. Twenty were low grade, of whic
h 12 showed a clonal band and eight showed a polyclonal smear pattern.
Eight were high grade, of which one revealed a clonal band, Three pro
duced polyclonal smear patterns and four cases were inadequate samples
, In one patient who had lymphoma at a second extranodal site, identic
al bands were identified, evidence for 'homing' of lymphoid cells towa
rds mucosal epithelium.