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Fat Free Mass and Sub-Cutaneous Fat Mass optimal cut-off to predict the overall survival. Results 54 patients (55.6%) were sarcopenic. There were 50 deaths in sarcopenic patients (92.6%) versus 26 deaths in non sarcopenic patients (60.5%). The median overall survival was 21.5 months in sarcopenic patients versus 61.3 months in no sarcopenic patients (p<0.001). Sarcopenia (SMI), BMI<21, NRI<97.5, and WHO status>0 were the only significant features in univariate analysis. In multivariate analysis sarcopenia was the only significant independent prognostic factor (HR=2.32[1.24- 4.34], p=0.008). We couldn’t define an optimal cut-off for Fat Free Mass and Sub-Cutaneous Fat Mass.

March 2017, the data of four consecutive patients with liver tumors were retrospectively analyzed in this study. All of the patients provided written informed consent prior to treatment. The fiducial marker was percutaneously placed, under local anesthesia, near the tumor by a hepatobiliary surgeon. The GA was 0.28 mm in diameter and 10 mm in length and had a shape that could be bent to fold the marker. MRI was performed 1 week after the implantation of the GA. Planning contrast- enhanced four-dimensional (4D) computed tomography (CT) scans and MRI images were used to determine gross tumor volume. The prescription radiation doses were designed to deliver the prescription dose to cover 95% of the planning target volume (PTV) in stereotactic body radiation therapy (SBRT) and to deliver the mean dose of the prescription dose for PTV in conventional radiotherapy using IMRT. IMRT was administered using volumetric modulated arc therapy (VMAT). A phantom study was performed in order to evaluate if the variety of the placed forms affects the precision of the verification. The GA was placed in three different forms (linear, folded, and tadpole-like forms) in gelatin. 4D-CT and 4D cone-beam CT (CB-CT) were performed in order to acquire the localization images.Then, automatic verification was performed between average images of the reference images and those of the localization images. Each 3D vector setup error was calculated from the acquired setup errors using the following formula; d3D=√dx2+dy2+dz2. Results All procedures for placement of GA were successfully performed with no complications. The GA showed various forms and was well detected in both CT and MRI and in CB-CT images in all fractions of the radiotherapy course. In the phantom study, no significant differences were observed in the automatic validated setup errors among the three different forms of the GA. Conclusion Our findings show that an iron-containing marker, the GA, is useful in image registration including CB-CT and MRI and that the tadpole-like shape can be recommended for liver radiotherapy. The present findings suggest that the GA will indeed be useful in clinical practice. EP-1426 ChemoRadiotherapy for Oesophageal cancer followed by Surgery Study (CROSS): Single Center Experience A. Tozzi 1 , C. Iftode 1 , T. Comito 1 , C. Franzese 1 , F. De Rose 1 , D. Franceschini 1 , G.R. D'Agostino 1 , G.A. Carta 1 , G. Reggiori 1 , M. Scorsetti 1 1 Istituto Clinico Humanitas, Radiotherapy and Radiosurgery, Rozzano Milan, Italy Purpose or Objective Multimodal approach is a standard treatment for locally advanced oesophageal and junctional cancer (OC). CROSS is one of the referral regimens for the treatment of this disease and it has been adopted as our center’s main regimen since 2012. The purpose of our study was to evaluate the role of volumetric-modulated arc therapy (VMAT) in the neoadjuvant chemoradiotherapy management of advanced medium and distal oesophageal cancer in terms of toxicity and response to treatment. Material and Methods From November 2012 to June 2017 consecutive fit patients (ECOG-PS) with resectable, locally advanced (T3-4,N0 and AnyT,N+ M0) OC were enrolled to receive neoadjuvant CROSS regimen. All underwent FDG-PET scanning before and after induction chemoradiotherapy. Pathologic uptake was observed in all patients. Patients showing no progression over neoadjuvant treatment were evaluated for oesophagectomy. Results The analysis included 66 patients, with a median age of 65 years (range of 40 - 81) and a generally low ECOG-PS

Conclusion Sarcopenia is a powerful independent prognostic factor, associated with a rise of the overall mortality in patients treated by exclusive radiochemotherapy for a locally advanced oesophageal cancer. PET-CT images are easily gathering data and can allow one to identify population at risk who needed an adapted therapy. EP-1425 Clinical implications of a novel iron- containing fiducial marker in radiotherapy for liver tumors. H. Doi 1,2 , S. Harui 1 , A. Sugimoto 1 , M. Fujiwara 1 , K. Kamino 1 , T. Nakajima 3 , S. Ikuta 3 , T. Aihara 3 , N. Yamanaka 3 , Y. Hishikawa 1 1 Meiwa Cancer Clinic, Department of Radiation Oncology, Nishinomiya, Japan 2 Kindai University Faculty of Medicine, Department of Radiation Oncology, Osaka-Sayama, Japan 3 Meiwa Hospital, Department of Surgery, Nishinomiya, Japan Purpose or Objective A 0.5%-iron-containing fiducial marker has been recently reported to have a high visibility in magnetic resonance imaging (MRI) and is possibly superior to markers containing no iron. However, only a few reports have reported the clinical implications of the 0.5%-iron- containing fiducial marker in radiotherapy for liver tumors. In this study, we report our findings regarding the utility of a 0.5%-iron-containing fiducial marker, Gold Anchor TM (GA; Naslund Medical AB, Huddinge, Sweden), in radiotherapy for liver tumors from our initial experience. Material and Methods Our institutional review board approved data collection and analysis (Approval No. 28–35). From June 2016 to