SELECTED CASE EIGHT years ago, a 62-year-old woman sought evaluation for an asymptomatic 2-cm mammographic abnormality in the upper part of the outer quadrant of her left breast. The results of an incisional biopsy were indicative of malignancy. After staging evaluation revealed no distant metastatic disease, she under-went a modified radical mastectomy with axillary node dissection. At the time of pathological review, a 2 × 2-cm estrogen receptor—positive infiltrating ductal adenocarcinoma was found; axillary lymph nodes were free of tumor (stage II, T2, NO, MO). Follow-up was uneventful until presentation 1 year ago, when the patientdeveloped progressive dyspnea on exertion, orthopnea, a dry cough, and a heaviness in the left side of her chest. At the time of examination, she was tachypneic and tachycardiac, and physical findings included dullness to percussion and absent left-sided breath sounds; she was admitted for treatment. A chest roentgenogram showed an opacified left hemithorax and