The pathophysiologic and roentgenologic effects of chest irradiation in breast carcinoma

We studied the effects of radiation therapy on lung function in 21 patients who underwent modified radical mastectomy and radiotherapy for breast carcinoma. The patients had pulmonary function studies and chest X rays prior to radiation therapy and at six weeks, and three, six, and twelve months following radiation therapy. All pulmonary function studies showed a small but statistically significant decline within the first three months following radiation therapy. Changes in the moderate and large airways continued to occur after three months. None of the changes in pulmonary function were reversible. Radiographic changes occurred in 12 patients. These changes occurred later than the lung function changes (median time for the changes was twelve months) and were unrelated to changes in lung function.