Session Item

Innovation in the oncological treatment of locally advanced lung cancer has increased patient survival; however, both antineoplastic drugs and thoracic irradiation can produce acute or chronic cardiotoxicity.

Our aim is to know the acute echocardiographic hemodynamic changes secondary to thoracic irradiation and to establish predictors of cardiac damage that will allow us to design strategies for the diagnosis and treatment of cardiac disease. 

Patients with locally advanced lung cancer who were candidates for thoracic radiotherapy were prospectively analyzed. An electrocardiogram (ECG) was performed before and after completion of radiotherapy and a baseline echocardiogram pre-treatment and at 3 months after completion of radiotherapy.

CTV-PTV and organs at risk: lungs, esophagus, great vessels and cardiac substructures (cavities, coronary arteries and valves) were contoured following cardiac contouring atlases. A dose of 50-66 Gy (1.8-2Gy/fraction) was administered in IMRT using MONACO for treatment planning.

Echocardiographic data, maximum, mean and minimum dose of each structure, PTV volume (cc), target coverage (D98%) and hotspots (D2%), lung V20, 10 and V5 and acute toxicity observed (CTCAE v.5) were collected. 

Analysis was performed with the paired two-sample t-test and ANOVA.  P-values < 0.05 were considered as statistically significant.

Fifteen patients were analyzed with a mean age of 65.4 years, 76.5% being male. Fifty-nine percent presented the neoplasm at the LSD. The majority histology was 35.3% squamous, and 23.5% undifferentiated non-small cell.

The mean PTV volume was 898.86 cc with a mean dose of 59.65 Gy (D98 52.74 Gy, D2 61.97 Gy). The mean pulmonary V20 was 24.12% and the mean esophageal dose was 26.89 Gy.

The mean dose received in the great vessels was 27.66 Gy in ascending aorta and 32.46 Gy in pulmonary artery. The mean dose achieved in cavities was 23.17 Gy in right atrium, 22.90 Gy in left atrium, 8.05 Gy in right ventricle and 6.76 Gy in left ventricle.

The mean doses achieved in the coronary arteries were 14.96 Gy in circumflex, 15.17 Gy in anterior descending and 10.19 Gy in right coronary. The mean dose in valves was: aortic 17.64 Gy, pulmonary 18.83 Gy, mitral 10.03 Gy and tricuspid 7.40 Gy. The mean cardiac dose received was 12.88 Gy.

No alterations were visualized between ECGs. After analyzing the changes between echocardiograms we found a mean increase in DTDVI, VTDVI, VTSVI, SLG, PAPs and E/e' volumes and a mean decrease in LVEF, TAPSE and LA volume, all without reaching statistical significance. Two patients presented pericardial effusion. Three patients (17.6%) presented G3 esophageal toxicity with resolution at subsequent follow-up. 

Thoracic radiotherapy does not increase cardiotoxicity in the acute setting.