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presented radiation induced liver disease RILD or toxic death. One patient had grade 3 gastric duodenal ulcers. Conclusion Our results indicate that SBRT is efficient and well tolerated for inoperable HCC. However, prospective randomized studies are warranted to confirm the place of SBRT in the treatment of HCC. EP-1423 variation of cardiac volume based on repeated enhanced 4DCT during radiotherapy in esophageal cancer X. Wang 1,2 , J.Z. Wang 2 , J.B. Li 2 , Y.J. Zhang 2 , F.X. Li 2 , W. Wang 2 , Y.L. Guo 3 , Q. Shao 2 , M. Xu 2 , X.J. Liu 2 , Y. Wang 4 1 University of Jinan-Shandong Academy of Medical Sciences, School of Medicine and Life Sciences, Jinan, China 2 Shandong Cancer Hospital affiliated to Shandong University, Thoracic Radiation Oncology, Jinan, Chile 3 Shandong Cancer Hospital affiliated to Shandong University, Department of PET-CT Room, Jinan, Chile 4 Shandong Cancer Hospital affiliated to Shandong University, Medical imaging department, Jinan, Chile Purpose or Objective Concurrent chemoradiotherapy (CCRT) is considered curative intent treatment for patients with non-operative esophageal cancer. Radiation-induced heart damage receives much attention. The aim of this study was to detect the change of cardiac volume over the course of radiotherapy for esophageal cancer based on repeated enhanced 4DCT and to explore the factors that might affect the change in cardiac volume during radiotherapy. Material and Methods In this prospective study, since September 2015 to January 2017, forty-six patients with pathologically proven thoracic esophageal squamous cell carcinoma who were scheduled to receive CCRT with a total dose of 60Gy in 30 fractions in our department were enrolled in the study. All the patients underwent enhanced 4DCT and 3DCT scans before radiotherapy and then repeated the CT scans every 10 fractions during treatment. The heart was contoured on 3DCT, end expiratory (EE) of 4DCT and maximum intensity projection (MIP) of 4DCT by the same radiation oncologist according to the same guidelines. Heart volumes and other relative parameters during radiotherapy were analyzed. Results The patients’ basic characters are summarized in table 1. Compared with the initial value, heart volume decreased significantly at the tenth fraction (reduction=3.27%, 4.45% and 4.52% respectively on 3DCT, EE and MIP, p<0.05) and the twentieth fraction (reduction=6.05%, 5.64% and 4.51% respectively on 3DCT, EE and MIP, p<0.05). The reduction between the initial measurement and the measurement at the thirtieth fraction was not significant (p>0.05). There was a decrease in both systolic (16.95±16.69mmHg, p<0.05) and diastolic blood pressure (7.14±11.64mmHg, p<0.05) and an increase in heart rate with 5.27±6.25 beats/min (p<0.05) after radiotherapy. The patients with mid-thoracic esophageal cancer were found to have significantly greater heart dose than the upper and lower tumors (p<0.05). As show in table 1, there was no correlation between the potential explanatory variables and heart volume change.

Conclusion By eliminating the effect of respiratory motion on the heart, 4DCT can better reflect the change of cardiac volume during radiotherapy of esophageal cancer. Heart volume was significantly reduced in the early treatment stage and maintained the reduction until the middle treatment stage, then showed a tendency to restore to the initial level at the thirtieth fraction. The blood pressure decreased and the heart rate increased during radiotherapy. These observed changes may be valuable indicators of cardiac impairment and target dose changes. EP-1424 Impact of sarcopenia in patients treated by radiochemotherapy for a Advanced Esophageal Cancer R. MALLET 1 , R. Modzelewski 2 , J. Lequesne 3 , H. Auvray 1 , A. Benyoucef 1 , F. Di Fiore 4 , P. Vera 2 , B. Dubray 1 , S. Thureau 1 1 Centre Henri Becquerel, Radiation Therapy, Rouen, France 2 Centre Henri Becquerel, Nuclear Medicine, Rouen, France 3 Centre Henri Becquerel, Clinical Research, Rouen, Franc 4 Centre Henri Becquerel, Medical Oncology, Rouen, France Purpose or Objective Sarcopenia is a prognostic factor for patients operated for oesophageal cancer. However, the impact of sarcopenia hadn’t been explored for patients treated by exclusive curative radiochemotherapy for a locally advanced oesophageal cancer. This study tries to evaluate its impact on this population. Material and Methods Clinical, nutritional, anthropometrics and functional- imaging (on 18 FDG-PET/CT) data were collected on 97 patients treated for a locally advanced oesophageal cancer between 2006 and 2012. L3-Skeletal Muscle was segmented on L3 cross-sectional CT images and normalized by patient’s height (SML3/h²) to obtain Skeletal Muscle Indice (SMI). Sarcopenia was defined by sex specific cut-off: SMI <38.5cm²/m² for women and 52.4cm²/m² for men. The primary end point was the overall survival. Secondary end points were to define a