ESTRO 36 Abstract Book

S360 ESTRO 36 _______________________________________________________________________________________________

analyze available literature data to provide guidelines on lymph nodes target volume delineation in unresectable biliary tumor. Material and Methods The systematic search of the electronic databases was performed from 1990 through July 2016. Primary outcome measure was the rate of lymph node involvement according to the primary biliary tumor location. Sites with ≥ 5% incidence of nodal metastases were considered in the clinical target volume for radiotherapy planning. Results Thirteen studies were included. The most frequent site of metastatic lymph nodes in intrahepatic biliary tree carcinoma was along the hepatoduodenal ligament [38.7%, 95%CI=31.0-47.0%]. Other frequently involved lymph nodes were the retroportal [61.1%, 95%CI=50.7-70-6%], the hilar [16.9%, 95%CI=13.2-21.4%] and the nodes along the common hepatic artery [17.0%, 95%CI=8.2-31.9%].In extrahepatic biliary tree cancer, the most frequently involved lymph nodes were along the hepatoduodenal ligament [40.3%, 95%CI=32.4-48.8%] and the pericholedochal nodes [42.7%, 95%CI=33.8-52.1%]. Other commonly involved nodal regions included retroportal lymph nodes [30.9%, 95%CI=23.0-40.1%], pancreaticoduodenal anterior and posterior nodes [30.1%, 95%CI=12.2-57.1%], paraaortic nodes [15.2%, 95%CI=8.0- 27.0%] and nodes along the common hepatic artery [19.7%, 95%CI=11.8-31.0%]. The most common site of metastases in gallbladder cancer were the nodes along cystic duct [23%, 95% CI=16.6-30.8%], the pericholedochal [25.2%, 95%CI=18.6-33.2%] and the retroportal nodes [17.1%, 95% CI=11.6-24.5%]. Conclusion Biliary tract cancer has a high propensity for regional lymphatic metastases. An evidence-based nodal target definition of biliary tract cancer based on primary tumor location was proposed. PO-0690 An initial result of carbon-ion radiotherapy for metastatic liver tumors. S. Toyama 1 , H. Suefuji 1 , M. Shinoto 1 , K. Matsumoto 1 , Y. Shioyama 1 1 Saga Himat Foundation, Ion Beam Therapy Center, Tosu, Japan Purpose or Objective To evaluate an efficacy and a safety of carbon-ion radiotherapy (C-ion RT) for metastatic liver tumors (MLT). Material and Methods We retrospectively analyzed 22 patients with MLT received the C-ion RT from April 2014 to March 2016. Male and female was 14 and 8, respectively. The median age at the treatment was 68 years old (range; 48-91). Regarding to the primary site, there were 14 patients with colorectal cancer (CRC) and the remaining 8 patients with the different malignancies. The median maximum diameter was 51 mm (range; 10-109). Seventeen patients had a singular disease and 5 had multiple ones. Out of all the patients, 17 patients received 60 Gy (RBE) for 4 fractions in 1 week, and 5 did 60 Gy (RBE) for 12 fractions in 3 weeks; the 12-fraction schedule was chosen when the tumors were close to the organs at risk: the digestive tract, the main trunk of the portal vein, the inferior vena cava, the common bile duct or the skin. The patients were fixed by thermoplastic fixation devices, and the tumor was irradiated from multiple directions with a respiratory synchronization. The overall survival (OS) and the local control rate (LCR) were calculated by a Kaplan-Meier method, and the statistical difference was evaluated by a log-rank test. Adverse events were classified according to the Common Terminology Criteria for Adverse Events version 4.0. Results The median observation duration was 383 days (range; 131-875), the 1-year OS and LCR were 90% and 79%, respectively. At the time of this analysis, 19 patients were

Conclusion Our favorable survival and toxicity data support the potential paradigm shift whereby the use of SBRT in oligorecurrent liver disease could benefit patients with unresectable or resectable liver metastases. Our study shows the importance of adequate dose coverage and proposes a prescription threshold dose of 45Gy on CTV and 43Gy on PTV to at least 95% of both volumes to significantly improve LC. PO-0689 clinical target volume in biliary carcinoma: a systematic review of pathological studies I. Marinelli 1 , L. Fuccio 2 , A. Guido 3 , A. Farioli 2 , V. Panni 3 , G. Ercolani 2 , G. Brandi 2 , S. Cammelli 3 , A. Galuppi 3 , G. Macchia 4 , R. Frakulli 3 , G. MAttiucci 5 , F. Cellini 5 , M. Buwenge 3 , M. Renzulli 2 , F. Deodato 4 , S. Cilla 4 , V. Valentini 5 , V. Tombolini 1 , R. Golfieri 2 , A. Morganti 3 1 Policlinico Umberto I, Division of Radiation Oncology, Rome, Italy 2 S.Orsola-Malpighi University Hospital, Department of Medical and Surgical Sciences, Bologna, Italy 3 S.Orsola-Malpighi University Hospital, Division of Radiation Oncology, Bologna, Italy 4 Fondazione Giovanni Paolo II, Division of Radiation Oncology, Campobasso, Italy 5 Sacro Cuore Catholic University, Division of Radiation Oncology, Rome, Italy Purpose or Objective Radiation therapy is a treatment option in both adjuvant and advanced biliary tract cancer. However, lymph nodes target volume delineation guidelines are lacking. Only generic indications are available but without specific recommendations for different primary tumor location (intrahepatic, extrahepatic biliary tract or gallbladder cancer). The aim of this study was to systematically