ESTRO 37 Abstract book

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ESTRO 37

Most of these tumors are poorly advanced when diagnosed and can be cured by removing them with or without a complementary treatment. When the tumor is more advanced, healing can be difficult or impossible and the aim of the treatment is palliative, decreasing or delaying the symptoms. The purpose of our study is to evaluate the role of exclusive palliative radiotherapy in those patients diagnosed with locally advanced bladder cancer who are not candidates for treatment with advanced age chemotherapy or associated comorbidities. To value the role of palliative radiotherapy (RT): identification of optimal candidates, outcome and length of palliation of symptoms and treatment-related toxicity. Material and Methods We retrospectively reviewed 17 patients treated between 2015-2017 with histologically diagnosed locally advanced urothelial carcinoma, not candidates for radical treatment with low perfomance status with advanced locoregional disease, metastatic or recurrent. All patients are treated with three-dimensional (3D) external radiotherapy with the same fractionation scheme: 42.4 Gy in fractionation of 265 cGy / day x 5 days / week. Results With a mean follow-up of 20 months, 100% of patients completed planned course of treatment. The median time to symptom progression is 8 months. The objective tumor response is Complete response: 29.4% (5), Partial / stabilization 70.58% (12). The median time to tumor progression was 8 months. The median overall survival is 10 months. The acute toxicity recorded after RT is genito-urinary G1 47% (8), transient urinary incontinence 35.3% (6), 0% radiation cystitis. Conclusion In patients with advanced urothelial carcinoma and non- subsidiary radical treatment, the exclusive hypofractionated palliative RT provides a satisfactory rate of disease control and symptom control with tolerable secondary toxicity. N. Klass 1,2 , I. De Pree 1 , E. Oomen-de Hoop 1 , M. Loi 1 , L. Otto-Vollaard 1 , A. Swaak-Kragten 1 , C. Van Zwienen 1 , J. Nuyttens 1 1 Erasmus MC Cancer Institute, Radiation-Oncology, Rotterdam, The Netherlands 2 University Hospital of Bern- Inselspital- University of Bern, Radiation Oncology, Bern, Switzerland Purpose or Objective Lung cancer is worldwide the most common cause of cancer related death. Most patients with lung cancer are already incurable at diagnosis and their prognosis is very limited. Despite new targeting treatment options, overall survival (OS) is usually still measured in months. To offer an optimal palliative treatment to these patients, especially towards end of life, a reliable estimation of OS is indispensable. Therefore, the aim of this study was to find new clinical factors related to OS. Material and Methods Prospectively, we collected 17 clinical factors in 168 patients with lung cancer who were referred to palliative radiotherapy between 09/2015 and 12/2016. We aimed to assess possibly relevant predictive factors on survival, including patient and tumour characteristics, social factors and medication (like morphine equivalent dose). EP-1656 Influence factors on limited overall survival in palliative patients with lung cancer

The Kaplan-Meier method and Cox`s proportional hazards model were used. Results Median overall survival was 2.95 months (95%CI, 2.37- 3.54). Median age was 66 years (range 32-91 years), 57% of patients were male. Most patients were diagnosed with adenocarcinoma (44%). Reason for referral were mainly bone metastases (49.4%), followed by brain metastases (33.3%). Out of 17 factors, 4 factors showed a significant relation with OS in univariate analysis: 1) Karnofsky performance score (KPS) <70 (HR: 2.13 [95%CI, 1.48- 3.08], p<.001), 2) age ≤66 (HR: 1.45 [95%CI, 1.02-2.05], p=0.037), 3) total number of metastases ≥4 at time point of treatment (HR: 3.92 [95%CI, 1.23-12.45], p=0.020), and 4) morphine equivalent dose >100mg/day (HR: 1.78 [95%CI, 1.15-2.75], p=0.010). Finally, in the multivariable analyses 3 of these factors remained statistically significant in relation to OS: 1) KPS (HR: 2.04 [95%CI, 1.37-3.03], p<.001), 2) age (HR: 1.65 [95%CI, 1.15-2.38], p=0.007), and 3) total number of metastases at time point of treatment (HR: 5.72 [95%CI, 1.39-23.55], p=0.016). Median OS of patients with a KPS <70 was only 1.8 months (range 1.13-2.47 months). Conclusion The present study has identified poor performance status (KPS <70), age ≤66 and ≥4 metastases at time point of treatment as strong negative prediction factors on OS. All 3 factors are easily applicable in the clinic. Among these factors KPS shows the highest impact and should be definitely be taken into account to identify patients who are most at risk of adverse outcomes after treatment. EP-1657 A Study of re-radiation rate after 8 gy single fraction radiotherapy to symptomatic bone metastases S. Juneja 1 , K.L. Bradley 1 1 Queen Alexandra Hospital, Hematology and Oncology, Portsmouth, United Kingdom Purpose or Objective Metastases to bones are frequently observed in advanced malignancies, leading to debilitating symptoms, affecting the quality of life adversely. Not uncommonly, metastatic vertebral deposits pose a threat to the spinal cord, and, if unaddressed, can lead to permanent neurological impairment. There are recent conflicting reports questioning the efficacy and longevity of response to 8 Gy / single fraction radiotherapy to bone metastases. Re- radiation rates have been reported to be as high as 25% in some studies. This real life study evaluates clinically observed re-radiation rates following this regimen in our institution, to find a cause for discrepancy of results, if any, and to establish an updated protocol for management of bone metastases, keeping patient and tumour factors into account. Material and Methods This is a single arm, retrospective study. Records of 100 patients and 154 sites of symptomatic bone metastases, treated in 2016 with 8 Gy/1 fraction of radiotherapy were studied. Re-radiation rate, median time to re-radiation, symptomatic improvement, tumour, patient and physician factors were examined. Kaplan Meier survival curves were plotted, median overall survival and survival from first treatment with 8 Gy/1 fraction was calculated for the cohort. Regression analysis and appropriate tests of significance are being applied to establish factors governing re-radiation. Available literature is being reviewed, with a view to propose an algorithm for management of bone metastases, with appropriate radiotherapy fractionation schedule.