Association between tangential beam treatment parameters and cardiac abnormalities after definitive radiation treatment for left-sided breast cancer.
OBJECTIVE
To examine the association between radiation treatment (RT) parameters, cardiac diagnostic test abnormalities, and clinical cardiovascular diagnoses among patients with left-sided breast cancer after breast conservation treatment with tangential beam RT.


METHODS
The medical records of 416 patients treated between 1977 and 1995 with RT for primary left-sided breast cancer were reviewed for myocardial perfusion imaging and echocardiograms. Sixty-two patients (62/416, 15%) underwent these cardiac diagnostic tests for cardiovascular symptoms and were selected for further study. Central lung distance and maximum heart width and length in the treatment field were determined for each patient. Medical records were reviewed for cardiovascular diagnoses and evaluation of cardiac risk factors.


RESULTS
At a median of 12 years post-RT the incidence of cardiac diagnostic test abnormalities among symptomatic left-sided irradiated women was significantly higher than the predicted incidence of cardiovascular disease in the patient population, 6/62 (9%) predicted vs. 24/62 (39%) observed, p = 0.001. As compared with patients with normal tests, patients with cardiac diagnostic test abnormalities had a larger median central lung distance (2.6 cm vs. 2.2 cm, p = 0.01). Similarly, patients with vs. without congestive heart failure had a larger median central lung distance (2.8 cm vs. 2.3 cm, p = 0.008).


CONCLUSIONS
Contemporary RT for early breast cancer may be associated with a small, but potentially avoidable, risk of cardiovascular morbidity that is associated with treatment technique.
Correa
Candace R
CR
Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA 19104, USA.
Das
Indra J
IJ
Litt
Harold I
HI
Ferrari
Victor
V
Hwang
Wei-Ting
WT
Solin
Lawrence J
LJ
Harris
Eleanor E
EE
D001943:Breast Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D016022:Case-Control Studies; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000209:etiology; D003326:Coronary Circulation; D004452:Echocardiography; D005260:Female; D006321:Heart / Q000033:anatomy & histology / Q000528:radiation effects*; D006333:Heart Failure / Q000175:diagnosis / Q000209:etiology; D006801:Humans; D008168:Lung / Q000033:anatomy & histology; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis / Q000209:etiology; D011832:Radiation Injuries / Q000150:complications*; D012189:Retrospective Studies