No serious late cardiac effects after adjuvant radiotherapy following mastectomy in premenopausal women with early breast cancer

Purpose: To assess cardiac mortality, coronary artery disease, myocardial d ysfunction, and valvular heart disease in women younger than 65 years of ag e, at least 10 years after adjuvant radiotherapy following mastectomy in ea rly breast cancer. Methods and Materials: Ninety women (45-64 years old) with Stage II breast cancer without relapse, included in the South Sweden Breast Cancer Trial (p remenopausal arm), with or without adjuvant postoperative radiotherapy +/- cyclophosphamide were examined with myocardial scintigraphy and echocardiog raphy/Doppler, 10-17 years after radiotherapy. Thirty-four patients had bee n irradiated for left-sided tumors, 33 for right-sided tumors, and 23 patie nts had not been treated with radiotherapy. The radiotherapy (conventional roentgen, electron beams, and high-energy photon beams combined, in each pa tient) included the chest wall and the regional lymph nodes, with a specifi ed target dose of 38-48 Gy, administered in daily fractions of 1.9-2.4 Gy, 5 days/week. Results: No cardiac deaths were found among the original 275 patients rando mized to adjuvant therapy. In the 90 patients examined, abnormal Endings we re recorded for ECG (14 patients), exercise test (5 patients), myocardial s cintigraphy (6 patients), thickening of valve cusps (14 patients), and mild valvular regurgitation (20 patients). All patients had normal systolic fun ction. Diastolic dysfunction was observed in 6 patients (abnormal relaxatio n in 4 patients and restrictive filling abnormality in 2 patients). Althoug h no significant differences were found between the 3 study groups, there w as a tendency to more abnormal findings after radiotherapy. Conclusion: Women younger than 50 years of age at the time of adjuvant radi otherapy following mastectomy in early breast cancer, had no serious cardia c sequelae 13 years (median) later, despite partly old-fashioned radiation techniques. (C) 1999 Elsevier Science Inc.