PO-0669: External validation of a survival model for stage III NSCLC: focus on similarities or differences?
Year: 2015
Type: conference-abstract
Abstract: Cardiac serum biomarker results will not be available for this cohort of patients.Cardiac MRI is performed on a Siemens 3.0 Tesla scanner.The imaging protocol includes short axis scans of the base, mid and apical positions of the left ventricle and 4-chamber scan, including standard cine scans for anatomy, mass and function.The cardiac MRI images are registered with the radiotherapy planning CT scan and analysed for the radiotherapy dose to cardiac macrostructures and the left ventricle 17 segment model.The radiotherapy dose will be correlated with cardiac MRI, ECG and cardiac biomarkers.Results: To date 24 patients have been recruited, 7 were withdrawn due to issues with completion of cardiac MRI scan, and 5 have completed the study.On treatment radiotherapy physics data has been analysed for 12 of these patients.Maximum radiotherapy dose was highest in the left (mean 4680cGy, 95CI (3711-5649) and right atria (mean 3885cGy, 95CI 2635-5135) compared to the left (mean 2625 cGy, 95CI 1567-3682) and right ventricles (mean 2448 cGy, 95CI 1678-3217) (p=0.005 and p=0.021 respectively).Furthermore review of the dose to the left ventricular segments, identified areas which received radiation dose in excess of 35Gy.Cardiac function, measured by cardiac MRI, was significantly affected during radiotherapy.There was a small but significant relative reduction in LVEF compared to baseline (-4.7%, p=0.040).In comparison, right sided cardiac function was more impaired, with a mean relative fall in RVEF of 21.6% (95CI 13.01-30.26,p < 0.0001).Conclusions: Preliminary evidence suggests an acute effect on right heart function by thoracic radiotherapy in NSCLC.Further analyses will be performed as the data matures.
Source: Radiotherapy and Oncology
Language: English
Subfield: Pulmonary and Respiratory Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
Estimated APC paid: $3,770
OpenAlex ID: W2593685012