Cytologic findings of hematologic malignancies in bronchoalveolar lavage fluid

Bronchoalveolar lavage (BAL) is often performed in leukemia and lymphoma patients with pulmonary infiltrates, mainly to rule out infection. However, malignant hematopoietic infiltrates are uncommon and a comprehensive cytologic study has not yet been performed.

We retrospectively reviewed all BAL samples from our institution for the past 22 years (November 1992-October 2014).

There were 37 cases of hematologic malignancies identified on BAL specimens (21 female patients and 16 male patients, age 22-80 years). Eighteen patients (49%) had pneumonia-like symptoms at the time of initial diagnosis of their malignancy, including fever, dyspnea, respiratory distress/hypoxia, and cough. The biopsy-proven cases were 25 leukemia (12 acute myeloid leukemia, 6 acute promyelocytic leukemia, 2 acute monocytic leukemia, 2 acute myelomonocytic leukemia, 1 chronic myeloid leukemia in blast phase, 1 large granular leukemia, and 1 plasma cell leukemia), 11 lymphoma (8 diffuse large B-cell lymphoma, 1 mantle cell lymphoma, 1 natural killer/T-cell lymphoma, and 1 T-cell lymphoma), and 1 multiple myeloma. Chest X-ray findings included opacities, consolidation, and interstitial edema. Four patients had BAL specimens with concomitant microorganisms. Eighteen patients subsequently died (2 days to 4 years), 15 were alive (3 weeks to 8 years of follow-up), and 4 were lost to follow-up.

BAL is especially important in distinguishing inflammatory/infectious processes from neoplastic disorders because many patients with hematologic malignancies can have pneumonia-like symptoms as part of their initial disease presentation. Causative pathogens are identified in only a minority of malignant BAL specimens from these patients. Lung involvement in patients with hematologic malignancies carries a poor prognosis.