ESTRO 36 Abstract Book

S759 ESTRO 36 _______________________________________________________________________________________________

Narumi 1 , Y. Uesugi 2 1 Osaka Medical College, Radiation Oncology, Osaka, Japan 2 Kansai University of Welfare Sciences, Medical treatment for health, Kashihara, Japan Purpose or Objective Goreisan （ TJ-17 ） is one of Japanese traditional Kampo medicine which is composed of five kinds of herbal medicines. TJ-17 has been found to suppress the abnormal water movement through the aquaporin inhibitory effect and an anti-inflammatory effect. Recently, TJ-17 has been indicated for cerebral edema and chronic subdural hematoma, and appears its effects soon. We have investigated whether the TJ-17 is effective in radiation enteritis. Material and Methods TJ-17 (7.5g/day) was administered 68 patients who received radiation therapy for the whole pelvis. The median age was 64 years old (range; 50-88). Fifty cases were male and eighteen cases were female. Sixty cases (92.6%) were combined chemotherapy (cisplatin and/or gemcitabine), eight cases received radiation alone. When patients showed the diarrhea grade 2 or more in the CTCAE v4.0, we administered TJ-17 without stopping radiation therapy. After prescription, we examined the number of defecation and stool property using a Bristol stool scale. Results All patients showed grade 2 or more diarrhea during radiation therapy. At the time of prescription, the median irradiation dose was 23Gy (range; 12-44). Before the administration, the median stool frequency was eight times (range; 4-20). Eighteen cases was type 6 (mushy stool), and fifteen cases was type 7 (watery) in the Bristol stool scale, the median scale was type 7 (average; 6.7). Bloody stools were observed in six cases. After one week administration of TJ- 17, fifty-three cases (77.9%) were improved the symptoms. In improved group, the median of decrease in the number of stool frequency was four times (range; 1- 19), and the median Bristol stool scale was type 6 (average; 5.4). Bloody stools were disappeared in three of 6 cases (50%). By using the Pearson product-moment correlation coefficient, from the appearance enteritis symptoms, it showed a correlation of moderate to start administering the TJ-17 earlier. Conclusion Japanese traditional Kampo medicines Goreisan (TJ-17) was effective against in acute radiation enteritis. EP-1421 Outcome by prognostic factors of AVM treated with LINAC:18 years experience, Spanish Institution S. Cafiero 1 1 Clinica de Occidente, Radiation Oncology, Santiago de Cali, Colombia Purpose or Objective Outcomes of cerebral arteriovenous malformations (cAVMs) treated with SRS by using LINAC, and results according to the Spetzler-Martin (SM) grading system and the Pollock-Flickinger (PF) score, in a series of patients (pts) from Onkologikoa in Spain Material and Methods 1995 to 2013, 320 pts with cAVMs treated with SRS by using a Clinac 21EX . Mean age 40 years ( 9-76), 61% men and 39% women. 57% of cAMVs in an eloquent area, 93% at the surface site (hemispheric/corpus callosum/cerebellar) and 7% at a deep site (basal ganglia/thalamus/ brainstem). Prior embolization in 36% of pts. A deep venous drainage was in 30% of cAVMs. The cAVM nidus volume PTV was divided into 3 groups: 0-2 cc (30.3%), 2.1

Science Centre- The Christie NHS Foundation Trust, Manchester, United Kingdom 10 University of Rochester, Medical Center, Rochester, USA 11 University of Manchester, Translational Radiobiology Group I Institute of Cancer Sciences- The Christie NHS Foundation Trust, Manchester, United Kingdom Purpose or Objective To define the optimal design and patient selection for interventional trials in radiogenomics, as radiogenomics do not give binary information like in e.g. targetable mutation biomarkers. Here, the risk to develop severe side effects is continuous, with increasing incidences of side effects with higher doses and/or volumes. Material and Methods The most appropriate interventions, endpoints, trial designs, model performance, identification of patient groups that could benefit most from a radio-genomic biomarker, and patient considerations were identified. Patients’ advocacy representatives were part of this work. Results Interventions that can be considered are: alternative treatment, dose modification, altered radiotherapy, mitigation / amelioration and the omission of postoperative radiotherapy in patients with a low risk for tumour recurrence. The optimal intervention is dependent on pre-defined risk factors, which were identified. There is clearly no simple endpoint or time point that can be selected when designing a clinical trial. Composite endpoints should be considered. Randomised clinical trials and retrospective observational studies have pros and cons in radiogenomics, which will be discussed. As model precision improves, thresholds can be relaxed, e.g., a very precise model could select patients for receiving a higher radiation dose with no risk of undue toxicity. Although more precise models will typically result in more benefit, less precise models might be informative to some degree. The consequences of the incidence of toxicity/toxicities on the number of patients needed for prospective validation as a function of the prevalence of a genetic profile must be considered. A polygenic risk score will likely be needed as individual genetic variants each contribute only modestly to risk of developing toxicity. Decreasing the standard radiation dose in the most susceptible patients is highly dependent on the dose- effect relationship.. These relations are highly dependent on the endpoint, e.g. radiation pneumonitis vs. fibrosis. An in-depth knowledge of the dose-volume relation for a specific endpoint taking into account the clinical usefulness of the dose reduction is needed in order to select the correct patient for this strategy. For the results of a study to be of value for patients, there should be a therapeutic alternative for the standard of care radiotherapy and the quantitative gain should be measurable and relevant. The incidence of peak reactions after radiotherapy is not the only parameter that should be taken into account. It is their severity, reversibility, the possible salvage treatments and the overall influence on quality of life that is also crucial to take into account. Conclusion The REQUITE and radiogenomics consortium has defined recommendations for the optimal design and patient selection for interventional trials using radiogenomic biomarkers, which will be presented in detail. Funding: EU 601826 SK: K07CA187546 NCI USA EP-1420 Effects of Japanese traditional Kampo medicines “Goreisan” for acute radiation enteritis H. Matsutani 1 , T. Shimbo 1 , H. Yoshioka 1 , N. Yoshikawa 1 , K. Yoshida 1 , M. Nakata 1 , T. Hamada 1 , T. Komori 1 , Y.