ESTRO 2022 - Abstract Book

S1098

Abstract book

ESTRO 2022

1 Medical Faculty University Hospital Magdeburg, University Clinic for Radiation Therapy, Magdeburg, Germany

Purpose or Objective We provide single-institution results for patients with non-resectable locally advanced cholangiocarcinoma, both with and without further neoadjuvant stereotactic body radiation treatment (SBRT) and chemotherapy. Materials and Methods Twenty-two consecutive patients with extrahepatic or intrahepatic cholangiocarcinoma had SBRT and were retrospectively evaluated between October 2017 and June 2021. No patient was a candidate for a liver transplantation , however three patients underwent a complete resection after SBRT. SBRT was delivered in 12 fractions with a median dose of 60 Gy. The toxicity of each participant was rated using the CTC for Adverse Events. Using the Kaplan-Meier technique, overall survival (OS), time to progression, and local control were calculated. Results The median follow-up was 15 months (range 3-29 months). The actuarial 1 year local control rate was 85 %. The 2-year OS rates was 30 %, , with a median survival of 15.7 months. The 1- and 2-year freedom from progression was 68% and 45 %, respectively. Median time to progression was 13 months. 20 patients (90%) experienced some form of acute grade 1-2 toxicity, most commonly fatigue or pain. no patient experienced grade ≥ 3 toxicity. Conclusion When cholangiocarcinoma cannot be surgically removed or in recurrence situation after surgery, SBRT may be considered as an alternative treatment option. It may be used as part of neoadjuvant therapy or as part of definitive treatment in patients with cholangiocarcinoma. Purpose or Objective The toxicity of the gallbladder from hypofractionated and stereotactic body radiation treatment is not well recognized (SBRT). In a retrospective cohort of patients with primary and metastatic liver cancers undergoing ablative-intent, we reported on gallbladder and bile system toxicity. Materials and Methods Between 2018-2021, 55 Patients underwent SBRT of liver lesions in our department. The Patients received 56-66 Gy in 5- 12 fractions. No gallbladder dose constraints were used at treatment, and gallbladder volumes and dose-volume histograms were created retrospectively. Attributable toxicity was defined as cholecystitis or perforation without preexisting gallbladder disease. Baseline factors were evaluated using Fisher exact test and the nonparametric K-sample test. The biliary system was irradiated with >20 Gy in 45 individuals. Twenty-five individuals had their gallbladders irradiated with more than 50 Gy. Only nine individuals had bile duct stenosis; all had preexisting cholelithiasis and received biliary stenting before RT. Conclusion We found no link between gallbladder dosage and toxicity and did not approach the maximum tolerable gallbladder dose in this radiation-treated group. To preserve the gallbladder during ablative and SBR treatments, we propose not limiting the dosage to the gross tumor volume. G.M. Petrianni 1 , M. Fiore 1 , P. Trecca 1 , G. D'Ercole 1 , L.E. Trodella 1 , C. Greco 1 , E. Ippolito 1 , D. Caputo 2 , R. Coppola 2 , S. Ramella 1 1 University Campus Bio-Medico of Rome, Radiotherapy, Rome, Italy; 2 University Campus Bio-Medico of Rome, General Surgery, Rome, Italy Purpose or Objective The aim of this study was to evaluate the safety and efficacy of induction treatments in patients with borderline resectable or unresectable locally advanced pancreatic cancer and the efficacy of pre-operatory staging with 18FDG PET-CT and laparoscopy in addition to CT scan. Materials and Methods From 2015 to 2021 we evaluated 42 patients with borderline resectable or unresectable pancreatic cancer. A pre-treatment staging was performed with CT scan, 18FDG PET-CT scan and laparoscopy. Patients with metastatic disease were excluded. Suitable patients received induction treatments with FOLFIRINOX. After 4 cycles patients were restaged with CT scan and Results The average duration of follow-up was 18.2 months (range, 3 -36 months). PO-1303 Prospective phase 2 study of induction FOLFIRINOX followed by chemoradiation in LA-Pancreatic Cancer PO-1302 Toxicity of the gallbladder with stereotactic body radiotherapy for liver tumors A. Gawish 1 , M. Walke 1 , T. Brunner 1 1 Medical Faculty University Hospital Magdeburg, University Clinic for Radiation Therapy, Magdeburg, Germany