Bronchoalveolar lavage in lymphangitic spread of adenocarcinoma to the lung.

We report the results of bronchoalveolar lavage in a patient who had pulmonary lymphangitic spread of adenocarcinoma from an unknown primary. The lavage specimen was remarkable for a large increase in the number of lymphocytes. This observation extends the differential diagnosis of a lymphocyte-predominant lavage specimen. The recovery of large numbers of lymphocytes associated with malignancy in this case suggests that bronchoalveolar lavage may also be useful to study aspects of the immune response to interstitial lymphangitic spread of malignancy to the lung.