Breast carcinoma in bronchoalveolar lavage. A cytologic and immunocytochemical study

To evaluate the effectiveness of bronchoalveolar lavage in detecting pulmonary metastases of breast cancer, we examined lavage fluid from 20 patients with routine cytologic preparations and immunoperoxidase stains with monoclonal antibody B72.3. Bronchoscopy was performed for infection surveillance prior to autologous bone marrow transplantation (nine patients), or to assess abnormal chest roentgenogram (11 patients). Metastatic adenocarcinoma was identified on Papanicolaou-stained-membrane filters in seven patients (35%), corroborated by transbronchial biopsy in four patients. No patients with chest roentgenogram suggestive of metastatic cancer or transbronchial biopsy positive for metastatic cancer had a negative lavage. Monoclonal antibody B72.3 uniformly marked malignant cell aggregates and many single cells that were inapparent in routinely stained material. Because bronchoalveolar lavage may detect metastatic adenocarcinoma with sensitivity comparable to transbronchial biopsy but with less morbidity, it is useful in the evaluation of pulmonary infiltrates in patients with primary breast carcinoma. Staining with monoclonal antibody B72.3 can be readily performed on lavage specimens and may serve as an adjunct in diagnosing malignancy.