C. Rapp J. Borkenhagen S. Klawikowski L.E. Rein E.M. Gore International Journal of Radiation Oncology, Biology, Physics POSTER VIEWING ABSTRACT| VOLUME 96, ISSUE 2, SUPPLEMENT , E429-E430, OCTOBER 01, 2016
Date
10/01/2016Abstract
Purpose/Objective(s)
The primary objective of this analysis is to determine the risk factors for early cardiac toxicity associated with radiation therapy to the thorax. Although the late cardiovascular effects of radiation are appreciated as a serious and life threatening complication in long term cancer survivors who have received thoracic radiation, the early effects are not as well characterized.
Materials/Methods
We retrospectively reviewed charts of 100 patients who received thoracic RT for lung or esophageal cancer with > 45 Gy at our institution from 2012-2015. Pre- and post-RT cardiac disease was evaluated by review of available notes, imaging, EKGs, and ECHOs. Univariate analysis with Cox PH regression modeling was used to evaluate association between cardiotoxicity and histology, esophageal vs. lung primary, gender, and history of hypertension (HTN), diabetes mellitus (DM), tobacco use, and peripheral vascular disease (PVD).
Results
Of the 100 patients, 73 were treated for lung cancer and 27 for esophageal. 83 received chemotherapy in addition to RT. Radiation median dose [min, max] for lung cancer was 60 Gy [44, 69] and for esophageal cancer was 50 Gy [50, 60]. Median follow-up was 1 year with a range of 2 to 40 months. A total of 32 patients had at least 1 cardiac event. Time to event ranged from 19 days prior to RT completion to 22 months post RT. Events included new pericardial effusion (n = 22), new arrhythmia (n = 9), new and worsening valvular disease (n = 3), and right bundle branch block (n = 2). There was a significant difference in incidence of post RT cardiotoxicity in patients treated for lung cancer with a history of DM (HR 2.59, P = .044). Additionally higher dose radiation for esophageal cancer was associated with higher rates of cardiotoxicity (HR 1.19, P = 0.044). The rate of cardiac events was higher although the difference was not statistically significant in patients with esophageal vs. lung cancer (HR 1.68, P = .186).
Conclusion
History of DM in lung cancer patients and a higher prescribed dose for esophageal cancer were associated with early cardiac toxicity. Detailed evaluation of RT doses to cardiac structures for both lung and esophageal cancer will help clarify this association. As more patients are added to this database and comprehensive analysis of dose to the cardiac substructures is completed, potential associations will become clearer.
Author List
Risk Factors for Early Radiation-Induced Cardiotoxicity in Lung and Esophageal CancerAuthor
Elizabeth M. Gore MD Professor in the Radiation Oncology department at Medical College of WisconsinView Online
