ESTRO 2022 - Abstract Book

S1069

Abstract book

ESTRO 2022

PO-1266 Evaluation of acute cardiac toxicity in locally advanced lung cancer patients

M. Cerrolaza 1 , M.D.M. Puertas 1 , C. Escuin 1 , V. Alonso 2 , D. De las Cuevas 2 , A. Lanuza 1 , B. García 1 , E. Moreno 2 , M. Tejedor 1

1 University Hospital Miguel Servet, Radiotherapy, ZARAGOZA, Spain; 2 University Hospital Miguel Servet, Cardiology, ZARAGOZA, Spain Purpose or Objective 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. Materials and Methods 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. Results 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.

Conclusion Thoracic radiotherapy does not increase cardiotoxicity in the acute setting.

PO-1267 Pulmonary toxicities after chemoradiation followed by durvalumab for stage III NSCLC: a real setting

C. Nicolet 1 , N. Briot 2 , C. Amoyal 1 , C. Chevalier 1 , C. Jeandidier 1 , C. Kaderbhai 3 , P. Foucher 4 , V. Westeel 5 , E. Martin 1

1 Centre Georges François Leclerc, Radiotherapy, Dijon, France; 2 Centre Georges François Leclerc, Statistical analysis department, Dijon, France; 3 Centre Georges François Leclerc, Medical Oncology , Dijon, France; 4 University Hospital Center François Mitterand, Thoracic Oncology, Dijon, France; 5 University Hospital Center Jean Minjoz, Thoracic Oncology, Besançon, France Purpose or Objective Evaluation of the incidence of pulmonary toxicities, especially pneumonitis, for patients treated in a real setting with concurrent chemoradiation (CRT) followed by adjuvant durvalumab for unresectable stage III non-small-cell lung cancer (NSCLC). Materials and Methods This study included retrospectively 84 patients with unresectable stage III NSCLC treated by CRT followed by durvalumab in 5 french centers from May 2017 to May 2021. Pneumonitis incidence was analysed with a distinction between immune pneumonitis, lung infection and radiation pneumonitis. A multivariate analysis was realized for radiation pneumonitis to find predictive factors. Overall survival (OS) and Progression Free Survival (PFS) were also evaluated. Results With a median follow-up of 23 months, grade 3-4 pneumonitis were as follows: 3.4% of radiation pneumonitis, 5.9% of immune pneumonitis and 13.4% of lung infections. . In multivariate analysis, age ≥ 68 years-old, cardiovascular history and use of docetaxel came out as predictive factors for radiation pneumonitis.