ESTRO 37 Abstract book

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ESTRO 37

commonest presenting symptom was post menopausal bleeding (84%) followed by pain (8%). 7 patients (28%) had a baseline performance status (PS) of 1 and 15 patients (60%) had a PS 2. Radiotherapy was planned and delivered conformally in 23 patients (92%). The most frequent fractionation regime was 30Gy in 6 fractions delivered twice a week over 3 weeks (84%) with a median delivered dose of 30Gy (27 – 30). 23 patients (92%) completed their treatment as planned. 68% of patients experienced grade 1 - 2 toxicities, mainly diarrhoea (48%). Only 2 patients (8%) experienced grade 3 – 4 toxicities; both were grade 3 diarrhoea where 1 was managed conservatively and completed treatment and another discontinued treatment as a result. 23 patients (92%) had documented symptomatic relief at follow up with resolution of bleeding and/or reduction in pain. 3 patients were lost to follow up and two patients were still alive at time of analysis. Although not all patients had further imaging later in their disease course, 18 had a documented progression date with a median progression free survival of 9.0 months (0.2 – 22.9). Estimated median overall survival was 14.8 months (0.1 – 31.6). Conclusion High dose hypofractionated palliative radiotherapy provides an effective and convenient treatment option for patients who are not suitable for radical therapy. It is effective at symptom control, is well tolerated and can potentially provide durable disease control. EP-1671 Inappropriate Radiologic Staging Examinations in Early-Stage Breast Cancer: A cost assessment T. Hijal 1 , H. Habibullah 2 , S. Rahman 2 , H. Almarzouki 2 , C. Freeman 1 , B. Gallix 3 1 Cedars Cancer Centre - McGill University Health Centre, Radiation Oncology, Montréal, Canada 2 McGill University, Radiation Oncology, Montréal, Canada 3 McGill University, Radiology, Montréal, Canada Purpose or Objective Cancer staging is essential before the initiation of therapy. A sizeable proportion of patients undergoes unnecessary staging tests, which are costly. This study seeks to quantify the cost of such unnecessary tests in patients with early-stage breast cancer in the province of Québec, Canada. Material and Methods All patients diagnosed with breast cancer between 2012 and 2014 at the McGill University Health Centre were included in this retrospective study. For each patient, the type and number of unnecessary staging tests, as per national guidelines, was extracted from the medical chart. The cost of each was obtained from Quebec government manuals of payment in order to derive the total cost of unnecessary staging tests. An extrapolation was then done to estimate the total cost for the whole province of Québec per year. Results Of 1845 patients with breast cancer listed in the cancer registry of the MUHC, 1116 had early-stage disease. 82.5% of these underwent at least one inappropriate staging test. Less than 0.5% of tests performed detected metastatic disease. The average cost of inappropriate Electronic Poster: Clinical track: Health services research / health economics

staging tests per patient was $235.84, $251.83 and $217.34 for 2012, 2013, and 2014 respectively, for an average 10-year cost to the province of Quebec of $8,306,596.18. Conclusion The majority of patients with early-stage breast cancer undergoes unnecessary staging tests at considerable cost to the single payer Québec government. EP-1672 Do physicians follow guidelines? A review of radiation therapy for uncomplicated bone metastases V. Di Lalla 1 , B. Fortin 2 , C. Pembroke 3 , C. Freeman 3 , M. Yassa 2 , T. Hijal 3 1 McGill University, Faculty of Medicine, Montreal, Canada 2 Hôpital Maisonneuve-Rosemont, Radiation Oncology, Montreal, Canada 3 McGill University Health Centre, Radiation Oncology, Montreal, Canada Purpose or Objective Best-practice guidelines recommend that patients receiving palliative radiation therapy for uncomplicated symptomatic bone metastases receive single fraction (SFRT) instead of multi-fraction radiation therapy (MFRT). Despite an association with higher retreatment rates, SFRT has been demonstrated to be more cost- effective and equivalent to MFRT in terms of pain control and toxicity. Global and national patterns of practice, however, reveal that SFRT is still underused, with significant intraprovincial variability in Canada. Our study assesses the use of SFRT and the factors that may influence treatment decisions at a large tertiary care center in Montreal, Canada. Material and Methods Patients who received radiotherapy (RT) for uncomplicated bone metastases between February 2014 and March 2015 were reviewed. Patient age, gender, primary histology, presence of spinal metastases, treatment site, and performance status were identified as potential factors affecting the choice of a single vs. multi-fraction radiation regimen. Predictors of fractionation regimen were explored by Fisher’s test on univariate analysis and logistic regression for multivariate analyses. Retreatment rates were analyzed with cumulative incidence and compared with Gray’s test. Results A total of 254 RT courses were administered to 165 patients. We demonstrated that 85.4% of treatments were performed using a single fraction of 8 Gy. Univariate analysis revealed that patients under 70 were more likely to receive MFRT (p=0.04), and breast histology was associated with higher rates of MFRT use (p=0.0046). Performance status (ECOG) was the only remaining significant predictor of fractionation on multivariate analysis because of high correlations between young age, breast histology, and ECOG (p = 0.03). Follow up was too short in 40% of patients to derive definitive conclusions on retreatment rates and predictors of retreatment. Conclusion In accordance with current guidelines, our study confirms that the use of SFRT in patients with uncomplicated symptomatic bone metastases at our centre is very high. We identified that patient age, primary histology, and performance status were factors that influenced fractionation choice. Further follow-up is needed to assess retreatment differences and other criteria that may also influence treatment choice.