Abstract Book

S85

ESTRO 37

Results Two hundred and five patients were treated with 20 Gy (31%), 30 Gy (38%) or 39 Gy (32%). In the departmental protocol, choice for any of the treatment schedules was based on expected survival, performance score, metastatic status, and, patient preference. Metastases were present in 81%, 79% and 20% in the 20 Gy, 30 Gy and 39 Gy group (p < 0.001). Most patients had symptoms of dysphagia (90%) and weight loss (73%), 61% had a dysphagia score > 2. Improvement of dysphagia was observed in 72%. At six weeks, after 20 Gy, 52%, after 30 Gy, 39%, and after 39 Gy, 39% had improved dysphagia scores of at least 1 point. Treatment with 20 Gy showed more recurrent dysphagia problems (59%), compared to 30 Gy (39%) and 39 Gy (37%). Treatment with 30 Gy and 39 Gy was related to longer time to second intervention compared to 20 Gy (HR 0.5; p = 0.05 and HR 0.3; p = 0.001, respectively) (Figure 1). Median OS after 20 Gy, 30 Gy and 39 Gy was 4.6 months (95% CI 2.6-6.6), 5.2 months (95% CI 3.7-6.7) and 9.7 months (95% CI 6.9-12.5), respectively (p = 0.02) (Figure 2). In univariate analysis, the 39 Gy group had longer OS. After correction for confounders, treatment schedule was no longer associated with survival. Poor performance status (HR 2.2, p < 0.001), recurrent oesophageal cancer (HR 1.69, p = 0.007) and distant metastasis (HR 1.7, p = 0.001) were significantly related to worse OS.

Conclusion Palliative EBRT provides good symptom control in the majority of patients with symptomatic oesophageal cancer. A higher dose schedule was related to a longer time to second intervention. Hence, life expectancy is valuable in selecting the optimal treatment schedule to prevent an unnecessary long treatment and limit the chance of second intervention when life expectancy is longer. Poor performance status, recurrent oesophageal cancer and distant metastasis are useful predictors of limited OS. OC-0166 Dose of stereotactic radiotherapy, local control and overall survival in cholangiocarcinoma T. Brunner 1 , O. Blanck 2 , V. Lewitzki 3 , N. Abbasi-Senger 4 , F. Momm 5 , N. Andratschke 6 , D. Habermehl 7 , S. Wachter 8 , W. Baus 9 , S. Gerum 10 , M. Guckenberger 6 , E. Gkika 11 1 Universitatsklinik Freiburg / University Hospitals Magdeburg, Dept. of Radiation Oncology, Freiburg / Magdeburg, Germany 2 University Medical Center Schleswig-Holstein- Saphir Radiosurgery Center, Department for Radiation Oncology, Kiel / Frankfurt Main / Güstrow, Germany 3 University Würzburg, Department of Radiation Oncology, Würzburg, Germany 4 Friedrich-Schiller-University Jena, 4Department of Radiation Oncology, Jena, Germany 5 Offenburg Hospital, Department of Radiation Oncology, Offenburg, Germany 6 University Hospital Zürich, Department of Radiation Oncology, Zürich, Switzerland 7 Institute of Innovative Radiotherapy- Helmholtz Zentrum Munich / Klinikum Rechts der Isar- TU Munich, Department of Radiation Sciences / Department of Radiation Oncology, München, Germany 8 Klinikum Passau, Radiation Oncology, Passau, Germany 9 University Hospital of Cologne, Department of Radiation-Oncology, Köln, Germany 10 Ludwig-Maximilians-University Munich, Department of Radiation Oncology, München, Germany 11 Universitatsklinik Freiburg, Dept. of Radiation Oncology, Freiburg, Germany Purpose or Objective Cholangiocarcinoma (CCC) is an orphan cancer with little progress and which is under-researched. Stereotactic body radiotherapy (SBRT) in conjunction with image guidance (IGRT) allows the application of escalated doses