TY - JOUR
T1 - The impact of cardiac radiation dosimetry on survival following radiotherapy for non-small cell lung cancer
AU - Vivekanandan, S.
AU - Landau, D.B.
AU - Counsell, N.
AU - Warren, D.R.
AU - Khwanda, A.
AU - Rosen, S.D.
AU - Parsons, E.
AU - Ngai, Y.
AU - Farrelly, L.
AU - Hughes, Lucy
AU - Hawkins, M.A.
AU - Fenwick, J.D.
PY - 2017/4/27
Y1 - 2017/4/27
N2 - Purpose The heart receives high radiation doses during radiotherapy of advanced-stage lung cancer. We have explored associations between overall survival, cardiac radiation doses and electrocardiographic (ECG) changes in patients treated in IDEAL-CRT, a trial of isotoxically-escalated concurrent chemoradiation delivering tumor doses of 63-73Gy. Patients and Methods Dosimetric and survival data were analyzed for 78 patients. The whole heart, pericardium, AV node, and walls of left and right atria (LA/RA-Wall) and ventricles (LV/RV-Wall) were outlined on radiotherapy planning scans, and differential dose-volume-histograms (dDVHs) were calculated. For each structure, dDVHs were approximated using the average dDVH and the 10 highest ranked structure-specific principal components (PCs). ECGs at baseline and 6 months post-radiotherapy were analyzed for 53 patients, dichotomizing patients according to presence or absence of ‘any ECG change’ (conduction or ischemic/pericarditis-like change). All-cause death-rate (DR) was analyzed from the start of treatment using Cox regression. Results 38% had ECG changes at 6 months. On univariable analysis, higher scores for LA-Wall-PC6, Heart-PC6, ‘any ECG change’ and larger planning target volume (PTV) were significantly associated with higher DR (p = .003, .009, .029 and .037 respectively). Heart-PC6 and LA-Wall-PC6 represent larger volumes of whole heart and left atrial wall receiving 63-69Gy. Cardiac doses ≥63Gy were concentrated in the LA-wall and consequently Heart-PC6 was highly correlated with LA-Wall-PC6. ‘Any ECG change’, LA-Wall-PC6 scores and PTV size were retained in the multivariable model. Conclusion We found associations between higher DR and conduction or ischemic/pericarditis-like changes on ECG at 6 months, and between higher DR and higher Heart-PC6 or LA-Wall-PC6 scores, which are closely related to heart or left atrial wall volumes receiving 63-69Gy in this small cohort of patients.
AB - Purpose The heart receives high radiation doses during radiotherapy of advanced-stage lung cancer. We have explored associations between overall survival, cardiac radiation doses and electrocardiographic (ECG) changes in patients treated in IDEAL-CRT, a trial of isotoxically-escalated concurrent chemoradiation delivering tumor doses of 63-73Gy. Patients and Methods Dosimetric and survival data were analyzed for 78 patients. The whole heart, pericardium, AV node, and walls of left and right atria (LA/RA-Wall) and ventricles (LV/RV-Wall) were outlined on radiotherapy planning scans, and differential dose-volume-histograms (dDVHs) were calculated. For each structure, dDVHs were approximated using the average dDVH and the 10 highest ranked structure-specific principal components (PCs). ECGs at baseline and 6 months post-radiotherapy were analyzed for 53 patients, dichotomizing patients according to presence or absence of ‘any ECG change’ (conduction or ischemic/pericarditis-like change). All-cause death-rate (DR) was analyzed from the start of treatment using Cox regression. Results 38% had ECG changes at 6 months. On univariable analysis, higher scores for LA-Wall-PC6, Heart-PC6, ‘any ECG change’ and larger planning target volume (PTV) were significantly associated with higher DR (p = .003, .009, .029 and .037 respectively). Heart-PC6 and LA-Wall-PC6 represent larger volumes of whole heart and left atrial wall receiving 63-69Gy. Cardiac doses ≥63Gy were concentrated in the LA-wall and consequently Heart-PC6 was highly correlated with LA-Wall-PC6. ‘Any ECG change’, LA-Wall-PC6 scores and PTV size were retained in the multivariable model. Conclusion We found associations between higher DR and conduction or ischemic/pericarditis-like changes on ECG at 6 months, and between higher DR and higher Heart-PC6 or LA-Wall-PC6 scores, which are closely related to heart or left atrial wall volumes receiving 63-69Gy in this small cohort of patients.
U2 - 10.1016/j.ijrobp.2017.04.026
DO - 10.1016/j.ijrobp.2017.04.026
M3 - Article
SN - 0360-3016
JO - International Journal of Radiation Oncology Biology Physics
JF - International Journal of Radiation Oncology Biology Physics
ER -
