ESTRO 37 Abstract book

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ESTRO 37

Transplantation, Freiburg, Germany 4 Medical Center University of Freiburg- Faculty of Medicine - University of Freiburg, Department of Radiology, Freiburg, Germany 5 Medical Center University of Freiburg- Faculty of Medicine - University of Freiburg, Department of General and Visceral Surgery, Freiburg, Germany 6 Medical Center University of Freiburg- Faculty of Medicine - University of Freiburg, Department of Radiation Oncology, Freiburg, Germany 7 Kliniken Maria Hilf- Moenchengladbach- Germany, Department of Radiation Oncology, Moenchengladbach, Germany Purpose or Objective To evaluate the feasibility and toxicity profile of reirradiation of recurrent primary or secondary liver tumors after stereotactic body radiotherapy (SBRT). Material and Methods Patients with hepatocellular carcinoma (HCC, n=8) cholangiocarcinoma (CCC, n=2) and liver metastases (LM, n=9) with a total of 23 lesions, with intrahepatic recurrence or progression after SBRT, underwent re-SBRT in 3 to 12 fractions with a median time of 7.4 (range: 2- 67) months between treatments. Results The median follow-up after re-irradiation for patients alive was 14 months with a median overall survival of 10 months. The median prescribed dose for the first SBRT was 45 (range: 33-66 Gy, EQD2 10 =56) Gy and 48 (range: 27-66 Gy, EQD2 10 =71) Gy for the re-SBRT. The median mean liver dose (D mean,liver ) was 7 (1-25) Gy with a corresponding EQD2 3 of 7 (0.2-25) Gy for the initial treatment and 10(1-63)Gy and 9 (1-67) Gy for the re- treatment. Of the 23 lesions 6 were re-irradiated in-field resulting in a median EQD2 3, maxium of 269 (range: 120-406) Gy for both treatments, with an α/β=3 to account for liver parenchyma, and a median EQD2 3, mean of 213 (range: 105-352) Gy. Treatment was well tolerated. Two patients with stent placement before SBRT developed a cholangitis 4 and 14 months after re-SBRT. One patient developed a CTC grade 3 gastrointestinal bleed. There was no radiation induced liver disease observed. Conclusion Repeated liver SBRT is feasible, without excessive liver toxicity, when there is no considerable overlapping with pre-irradiated portions of the stomach or bowel. EP-1433 Induction chemotherapy of albumin-bound paclitaxel in carcinoma of esophagus unsuitable for surgery A.K. Gandhi 1 , M. Rastogi 1 , S.S. Nanda 1 , S. Rath 1 , R. Khurana 1 , R. Hadi 1 , K. Sahni 1 , A. Srivastava 1 , S. Farzana 1 , S. Mishra 1 1 Dr Ram Manohar Lohia institute of Medical Sciences, Radiation Oncology, Lucknow, India Purpose or Objective Weekly chemotherapy (WK-PC) with concurrent radiation (CCRT) using solvent based paclitaxel (SB-Pac) and carboplatin as neo-adjuvant treatment prior to surgery is the standard of care for resectable carcinoma of oesophagus. WK-PC as induction regimen (NACT) followed by definitive radiotherapy (RT) or CTRT with WK-PC is a novel approach in patients unsuitable for surgery or cisplatin based CTRT; however the tolerance of this regimen could be an issue. With a hypothesis that this regimen could be better tolerated if nano-particle albumin bound paclitaxel (NB-Pac) is used instead of SB- Pac, we aimed to evaluate the role of this regimen using NB-Pac. Material and Methods Details of 52 patients (Jan 2013-Dec 2016) of histopathologically proven carcinoma of oesophagus deemed unsuitable for surgery or cisplatin based CTRT

standard therapies based on up-front surgery followed by adjuvant treatments. Aim of this systematic review is to analyze the current evidences of literature on the impact of neoadjuvant chemoradiation on outcome of patients with resectable PC Material and Methods A systematic review of literature from 2000 to 2017 on Pubmed and Scopus was performed. We included retrospective and prospective studies published in English enrolling more than 25 patients. Overall survival was the primary endpoint. Secondary endpoints included local control, acute and late toxicity, perioperative complications, response rate, R0 resection rate, and pCR rate Results A total of 16 studies including 1411 patients met the selection criteria. Median local failure rate was 12% (range: 0-29.7%). Out of operated patients, median R0 resection rate was 92% (range: 68-100%). Only 9 papers reported pCR rate with a median value of 3.8% (0-17.6%). Median survival in patients with resected PC was 27 months (range: 11.7-50.2 months) compared to patients not undergoing surgery (median: 9.5 months; range: 5.5- 11.0 months). Median acute gastrointestinal ≥ G3 toxicity rate was 19.2% (range: 3.0-40.7%)

Conclusion Neoadjuvant therapy is feasible and relatively safe, able to improve R0 resection rate and median OS, with a positive impact on local control. The role of this therapy is still debated and controversial and only prospective randomized controlled trials with adequate sample size will clarify the real benefit of neoadjuvant therapy in resectable PC EP-1432 Safety of repeated stereotactic body radiotherapy (SBRT) for recurrent liver malignancies. E. Gkika 1 , I. Strouthos 1 , S. Adebahr 1 , S. Kirste 1 , D. Bettinger 2 , R. Fritsch 3 , V. Brass 2 , L. Maruschke 4 , H.P. Neeff 5 , S.A. Lang 5 , U. Nestle 6,7 , A.L. Grosu 1 , T. Brunner 1 1 University Medical Center Freiburg, Department of Radiation Oncology, Freiburg, Germany 2 Medical Center University of Freiburg- Faculty of Medicine - University of Freiburg, Department of Medicine II, Freiburg, Germany 3 Medical Center University of Freiburg- Faculty of Medicine - University of Freiburg, Department of Internal Medicine- Haematology- Oncology and Stem-Cell