A Descriptive Study of Pulmonary Complications After Postoperative Radiation Therapy in Node-Positive Stage II Breast Cancer

Abstract

This study was conducted to assess the frequencies of symptomatic pulmonary complications following adjuvant postoperative radiotherapy using different treatment techniques in patients with Stage II node-positive breast cancer. During 1991–1993, 177 patients were referred to the Radiotherapy Department of Stockholm Söder Hospital; 144 after modified radical mastectomy and 33 after partial mastectomy. The records of these patients were studied retrospectively for clinically diagnosed radiotherapy-induced lung complications 1–7 months after treatment. Thirty-three of 138 patients (24%) irradiated after modified radical mastectomy developed pulmonary complications and 20 (14%) of these were diagnosed as severe, i.e. needing medical treatment with corticosteroids. No statistically significant difference could be found between the different electron energies used for treating the chest wall and the frequency of respiratory side-effects. Eighteen of 33 patients completed the prescribed treatment after partial mastectomy. Nine of these 18 patients (50%) developed pulmonary complications and 4 (22%) developed severe reactions. Fifteen patients received alternative treatments. With the techniques used after partial mastectomy the median central lung distance was 32 mm among the patients who experienced respiratory side-effects compared with 25 mm among the patients who were not affected (p = 0.03). This study identifies acute/subacute pulmonary side-effects as a clinically significant problem. Prospective follow-up with lung function tests, identification of risk factors, and individual lung dose volume histograms is warranted to assess the long-term implications.