Bronchoalveolar lavage is a useful diagnostic tool in diffuse or disseminated lung
malignancies that do not involve the bronchial structures visible by endoscopy. The
neoplastic histotype and the intraparenchymal neoplastic growth pattern are good predictors
for diagnostic yield; adenocarcinoma, and tumors with lymphangitic or lepidic growth
patterns are more easily diagnosed by bronchoalveolar lavage; in these cases the diagnostic
yield reported is higher than 80%. In hematologic malignancies the diagnostic yield
is quite good in secondary diffuse indolent B cell lymphomas and in primary B cell
lymphomas of mucosa-associated lymphoid tissue (MALT) type but low in Hodgkin disease.
Morphological analysis may be implemented by immunocytochemical or molecular tests
to identify the cell lineage and the presence of monoclonality. Disorders in which
bronchioloalveolar cell hyperplasia/dysplasia is a significant morphological component
may have cytological features in bronchoalveolar lavage fluid that mimic lung neoplasms:
acute respiratory distress syndrome (ARDS), acute interstitial pneumonitis (AIP),
and acute exacerbation of idiopathic pulmonary fibrosis are the most important clinical
entities in this group.
Bronchoalveolar lavage - bronchioloalveolar cell carcinoma - lymphoproliferative lung
disorders - carcinomatous lymphangitis - lung neoplasms