ESTRO 37 Abstract book

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ESTRO 37

univariate sensitivity analysis. Then, incremental cost- effectiveness ratio (ICER) was calculated to verify the cost against the clinical outcome. Finally, a simulation of public payer’s expenditures for the treatment of early breast cancer with APBI and WBI in 2013 and 2025 has been conducted. Results The average cost of treatment with APBI is lower than for WBI, even assuming a potential increase in the unit price of the former procedure. There was no additional health benefit of WBI and the calculation of cost-effectiveness was based on the absolute difference in overall local control rate. However, this difference (0.92% versus 1.44%) was fairly minimal and was not identified as statistically significant during 5 years. Conclusion The use of APBI as an alternative to WBI in the treatment of early breast cancer would substantially reduce healthcare expenditures in both 2013 and 2025, even assuming an increase in the price per single APBI procedure. EP-1348 Target Delineation Of Internal Mammary Nodes in Locally advanced Breast Cancer G. Narayanan 1 , R. Kumar 2 1 Vydehi Institute of Medical Sciences, Radiation Oncology, Bangalore, India 2 Vydehi Institute of Medical Sciences, Radiation Oncology, gurgaon, India Purpose or Objective Regional nodal irradiation as a component of both postmastectomy and postl umpectomy radiation has been shown in numerous randomized trials and meta-analyses to have a significant impact on locoregional control, breast cancer mortality, and, in some cases, overall survival. A recent meta-analysis showed an improvement in overall survival on addition of internal mammary nodes as a target in nodal radiation. There is paucity on data on IMN contouring, though ESTRO recommends a margin of 5mm around the internal mammary vessels, there is no objective proof of what percentage of nodes would get covered in a treatment naive patient when we use a 5mm margin. We intend to investigate the same. Material and Methods 30 clinically node positive non metastatic consenting breast cancer patients were subjected to a diagnostic contrast-enhanced CT, reconstructed to 1.25 mm slice thickness. Internal mammary vessels were contoured on the treatment planning system and an isotropic margin of 2.5, 5, 7 and 10mm were given. With each margin, percentage of the covered or missed nodes was recorded. Total number of nodes and its location with respect to the tumor location was also recorded. Results 147 nodes in total were contoured in the studied 30 treatment naïve patients. 8%, 72%, 96% and 100% of the nodes were covered using margins of 2.5, 5, 7 and 10mm margins respectively. Nodes were located anteriorly medially or laterally and no nodes were found posteriorly. Maximum Nodes were found in the 1 st , 2 nd and 3 rd intercostal space with an occasional node in the 4 th 5 th and 6 th spaces

Conclusion Stereotactic body radiation therapy using the CyberKnife system is a suitable APBI technique for the treatment of select early-stage breast cancer patients. Early outcomes are comparable with other APBI techniques while producing significant normal tissue sparing and excellent short-term cosmetic outcomes. Longer follow up is required to assess oncologic outcomes and late toxicity. multicatheter brachytherapy in early breast cancer –simulation of treatment costs M. Harat 1 , A. Harat 2 , R. Makarewicz 3 1 Collegium Medicum- Nicolaus Copernicus University, Radiotherapy, Bydgoszcz, Poland 2 Collegium Medicum- Nicolaus Copernicus University, Public Health, Bydgoszcz, Poland 3 Collegium Medicum- Nicolaus Copernicus University, Brachytherapy, Bydgoszcz, Poland efficacy of accelerated partial-breast irradiation (APBI) in the treatment of early breast cancer is non-inferior to that of whole breast irradiation (WBI) commonly used in this indication. The aim of this study was to compare the costs of treatment with APBI and WBI in a population of patients after conserving surgery for early breast cancer, and to verify if the use of APBI can result in direct savings of a public payer. Material and Methods The hereby presented cost analysis was based on the results of GEC-ESTRO trial. Expenditures for identified cost centers were estimated on the basis of reimbursement data for the public payer. After determining the average cost early breast cancer treatment with APBI and WBI over a 5-year period, variance in this parameter resulting from fluctuations in the price per single procedure was examined on EP-1347 WBI vs APBI using Purpose or Objective A recent large phase 3 trial demonstrated that the