Abstract Book

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ESTRO 37

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 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. 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 = EP-1672 Do physicians follow guidelines? A review of radiation therapy for uncomplicated bone metastases

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. A.B.B. Borges 1 , C.B. Budib 1 , F.C. Batista 1 , M.D. De Mattos 1 , D.A. Cunha 1 , A.G. Zucca-Matthes 1 , S.A. McCloskey 2 1 Barretos Cancer Hospital, Radiotherapy, Barretos, Brazil 2 UCLA - University of California, Radiotherapy, Los Angeles, USA Purpose or Objective To evaluate distance between patient’s hometown (HT) and the Radiotherapy Center (RC) in patients treated with APBI (acelerated partial breast irradiation) and to review initial outcomes after implementing this technique. Material and Methods Patients treated with APBI in a Brazilian Cancer Center, between October 2014 and October 2016 were evaluated. All patients treated met the “Suitable” criteria for APBI per the ASTRO 2017 consensus statement. The radiotherapy regimen used was 10 x 3.85 Gy, 5 times per week, delivered using an external beam three dimensional conformal technique. The distance between HT and RC was calculated for each patient receiving APBI. Secondary endpoints evaluated included overall survival (OS), locoregional recurrence free survival (LRF) and acute toxicity. Acute toxicity was assessed using the RTOG / EORTC scale. Results We included 26 patients, with median follow-up of 12 months (range 7 – 26 months) and median age 70 years (range 55 – 85 y). The median elapsed days for radiation delivery was 14 days (range 11-20 days). At the time of this analysis there were no recurrences and there was one death unrelated to cancer or cancer treatment. The only observable toxicity was Grade 1 dermatitis which occurred in 19% of patients. There were no Grade 2 or higher toxicities. Distance between HT and RC was ≤50km in 23%, 51-100km in 19%, 101-200km in 8%, 201- 400km in 31%, and >400km in 19%. Conclusion More than 50% of patients receiving APBI in our initial experience live >200km from the radiation center. We believe this technique can serve to significantly reduce the logistic and social impact of radiation therapy, especially in low and middle income countries where treatment centers are scarce, as Brazil, by reducing the treatment days and thus time displaced from home. EP-1674 financial burden of cervical cancer in patients treated at a tertiary health facility in Nigeria M.I. Mustapha 1 , M. ALI-GOMBE 2 , A. ABDULLAHI 3 , A. ADENIPEKUN 4 , O.B. CAMPBELL 4 1 RASHEED SHEKONI TEACHING HOSPITAL, RADIATION AND CLINICAL ONCOLOGY, DUTSE, Nigeria 2 GOMBE STATE UNIVERSITY, RADIOTHERAPY, GOMBE, EP-1673 Can APBI reduce the logistic/social impact of breast cancer treatment in Middle Income Country?