ESTRO 36 Abstract Book

S394 ESTRO 36 _______________________________________________________________________________________________

7 Hospital Txagorritxu, Radiation Oncology, Vitoria, Spain 8 Hospital Virgen del Rocio, Radiation Oncology, Sevilla, Spain 9 Hospital Virgen Macarena, Radiation Oncology, Sevilla, Spain 10 Hospital Sanchinarro, Radiation Oncology, Madrid, Spain 11 Cruces University Hospital, Clinical Epidemiology Unit, Barakaldo, Spain Purpose or Objective Elderly frequently receive different medical treatments than younger patients because of fear of higher toxicity and expected lower effectiveness. Painful bone metastases have a major impact on quality of life of cancer patients. We investigated whether age is a predictor for pain response after radiotherapy (RT) for painful bone metastases. Material and Methods Between June 2010 and June 2014, 204 pati ents from ten Radiation Oncology Departments in Spain parti cipated in a prospective observational study* to evaluat e the flare effect in patients with bone metastasis undergoing palliative RT. The pre-treatment evaluation con sisted of a full history and physical examination, administration of Brief Pain Inventory (BPI) and record of analgesic consumption within the previous 24 h. A follow-up visit was scheduled 4-weeks after the end of the RT. At this time the BPI was again administered, and analgesic consumption was recorded. From this cohort, 128 patients (62.7%) completed the BPI at the first visit and in the follow-up (4-weeks after RT), and therefore were evaluable for treatment response in the present study. Pain response was measured using the International Bone Metastases Consensus from 2002. Worst pain was recorded using the Brief Pain Inventory (BPI): ranged from 0–10. To identify which variables predicted pain response and in particular to determine whether age is a predictor, Cox proportional hazard models were used. The preselected baseline variables, were age (cohorts ≤65 (A)/ 65- 75 (B)/ >75 (C) ), gender, Eastern Cooperative Oncology Group (ECOG) performance status scale (0-1/≥2), pain score (≤4/5–7/8–10), treatment schedule (single fraction/multiple), primary tumor (prostate / breast / lung / other cancer types), presence of visceral metastases (yes/no), concomitant systemic chemotherapy (yes/no) and concomitant bisphosphonates (yes/no). Results Table 1 shows patient characteristics. Median age was 66 years (38-89). Overall treatment response (including partial and complete responses) was 61.7%. According to univariate analysis pain response was significantly better in patients > 75(C) years: 53.6% in (A) versus 60.9% in (B) (OR, 1.3; 95% CI, 0.6-2.9; p=0.459) and 80.8% in (C) (OR, 3.6; 95% CI, 1.2-11.0; p=0.022 ). Patients receiving multiple fractions presented better response (70.5%) that those receiving a single fraction (49.5%) of 8 Gy (OR, 2.8; 95% CI, 1.2-6.1; p=0.01 ). Moreover, patients presenting a pain score of 8-10 before RT presented better response (70.8%) than those with a pain score <8 (50%) after palliative RT (OR, 2.4; 95% CI, 1.1-5.0; p= 0.017 ). No other factors previously mentioned were found statistically significant. The multivariate analysis showed that only the treatment schedule (p = 0.005) and the pain score >8 before RT (p = 0.011) were independent factors for pain response.The age was not found a statistically significant factor.

respectively. The directives were reviewed with physician staff within in the first week of enactment; directives were allowed to be edited at the physician’s discretion if an alternative fx was indicated. Patients treated with SBRT were excluded from analysis. Retrospective chart review of patients treated between 1/2012 and 9/2016 revealed 1233 treatment courses (888 unique patients). Statistical analysis included the Chi square test. Results Following implementation, treatment directives were used for 89% of cases (n=125) and were modified to an alternative prescription in 17 cases. Among directive- based treatments, 27% were simple metastases and 73% were complex. Single fx use increased from 17% to 25% among palliative bone metastasis treatments (p=0.02) and hypofractionation (1 or 5 fx) utilization increased from 72% to 88% (p<0.001)(Figure 1). Among simple and complex treatments, the default fractionations (1 fx or 5 fx, respectively) were selected in 84% and 87% of cases.

Conclusion Setting defaults for palliative treatment through an institution-wide adoption of evidence-based, treatment- guiding directives proved to be a straightforward and successful intervention, which significantly increased the utilization of hypofractionation. Our data suggests that treatment directives may be a useful approach in overcoming resistance to other hypofractionated treatment paradigms. Further palliative treatment directive use is planned within our institution for other sites (lung, pelvis). We believe that widespread examination and adoption of evidence-based directives can be used to improve value and reduce overtreatment in palliative oncologic care. PO-0748 Efficacy of radiotherapy for painful bone metastases in elderly patients J. Cacicedo 1 , A. Gomez-Iturriaga 1 , L. Sanchez 2 , A. Navarro 3 , V. Morillo 4 , P. Willisch 5 , C. Carvajal 6 , E. Hortelano 7 , J. Lopez-Guerra 8 , A. Illescas 9 , F. Casquero 6 , O. Del Hoyo 6 , R. Ciervide 10 , L. Martinez-Indart 11 , P. Bilbao 6 1 Hospital Universitario de Cruces, Radiation Oncology- Cruces University Hospital, Baracaldo-Vizcaya, Spain 2 Univesrsity of the Basque country, Medicine Faculty, Barakado, Spain 3 Instituto Catalán de Oncologia, Radiation Oncology, Hospitalet Barcelona, Spain 4 Hospital de Castellón, Radiation Oncology, Castellón, Spain 5 Hospital Meixoeiro, Radiation Oncology, Vigo, Spain 6 Hospital Universitario de Cruces, Radiation Oncology, Barakaldo, Spain Poster: Clinical track: Elderly