Bronchoalveolar lavage in bronchiolitis obliterans organizing pneumonia primed by radiation therapy to the breast.

Abstract

Growing evidence indicates that unilateral lung irradiation for breast cancer may "prime" the development of migratory lung infiltrates with histologic features of bronchiolitis obliterans organizing pneumonia. Our purpose was to evaluate the cytologic and immunocytologic features of bronchoalveolar lavage in this condition. We analyzed the profile bronchoalveolar lavage cell differentials and lymphocyte subpopulations of 11 women with bronchiolitis obliterans organizing pneumonia syndrome after radiation therapy for breast cancer in comparison to 9 healthy women. The bronchoalveolar lavage analysis demonstrated a significant increase in the percentage of lymphocytes (36.7% +/- 5.4% vs 8.6% +/- 1.1%, P =.0002), neutrophils (3.8% +/- 1.2% vs 0.6% +/- 0.2%, P =.005), eosinophils (2.4% +/- 1% vs 0.3% +/- 0.1%, P =.01), and mast cells (1.4% +/- 0.6% vs 0.1% +/- 0.02%, P =.05) with a significant decrease in the percentage of macrophages (56.1% +/- 6% vs 90.3% +/- 1.4%, P =.0002) in patients with bronchiolitis obliterans organizing pneumonia compared with the control subjects. The percentage of CD3(+) cells was significantly increased in patients with bronchiolitis obliterans organizing pneumonia (93.7% +/- 1.3% vs 70.9% +/- 4%, P =.0004), with a significant decrease in CD4(+) cells (32.7% +/- 4.7% vs 55.4% +/- 2. 6%, P =.002) and a significant increase in CD8(+) cells (61.2% +/- 4. 8% vs 37.5% +/- 2.9%, P =.003) in comparison to control subjects. The CD4/CD8 ratio was significantly reduced in patients with bronchiolitis obliterans organizing pneumonia compared with control subjects (0.6% +/- 0.1% vs 1.5% +/- 0.1%, P =.001). These data add to the view that unilateral lung irradiation for breast cancer may "prime" the development of a syndrome quite similar to idiopathic bronchiolitis obliterans organizing pneumonia.