Intraoperative open-cavity implant (IOCI) technique for accelerated partial breast irradiation (APBI) using HDR multicatheter brachytherapy for breast cancer patients with small breasts.

e11088 Background: Breast-conserving treatment (BCT) is comprised of lumpectomy followed by whole-breast irradiation (WBI). The efficacy of an accelerated partial breast irradiation (APBI) has been investigated compared with WBI. APBI starting just after surgery might give more benefit by intraoperative insertion of catheters. Although balloon catheter-based APBI is available in the US, it would not be adapted for Asian women with small breast. When the applicators are implanted during operation for the tumor, APBI can start just after surgery. The aim of this study is an assessment of the efficacy and safety of APBI using Intraoperative Open-cavity Implant (IOCI) technique. Methods: Patients (≥ 40 yrs) with invasive breast cancer (≤ 3 cm) were enrolled. Before the lumpectomy, the insertion of applicators and delivery doses were simulated with CT. After the confirmation of the free margin and negative SNs for metastasis using frozen section analysis, applicators were inserted. Dose distribution analysis, ...