ESTRO 2021 Abstract Book

S168

ESTRO 2021

safe, effective, and efficient radiation care and delivery. The development of those leadership skills is not necessarily an inherent process. At some point in the life of every radiation therapist, the demonstration of leadership will be expected of them; they must be prepared accordingly. In the presentation of this talk, the subject matter will introduce the participants to the essentials of leadership and the challenge of leading others. Discussion on setting and communicating direction and the avoidance of derailment will be presented. The presentation will examine concepts of leadership style and therapist motivation. Also, the management of change and innovation will be presented as a critical skill set in surpassing any level of status quo operations. The presentation will also highlight the role of influence and persuasion and the means of building credibility to energize staff to stretch and perform at expected levels and beyond. Finally, the presentation will provide practical examples throughout the session on using leadership skills geared towards this group. SP-0259 In-breast recurrences: Patients selection for salvage lumpectomy and brachytherapy P. Csaba 1 1 National Institute of Oncology, Center of Radiotherapy, Budapest, Hungary Abstract Text Breast-conserving surgery (BCS) and postoperative radiotherapy (RT) became widely accepted for the treatment of early-stage invasive breast cancer in the last four decades. In spite of adequate BCS and RT, the rate of ipsilateral breast tumor recurrence (IBTR) is approximately 10%. In such cases salvage mastectomy (MT) is the standard treatment, however second BCS is also a reasonable option for selected patients. The incidence of second local recurrence (LR) after repeat conservative surgery has been reported in the range of 7 to 50%, which can be decreased with reirradiation using interstitial brachytherapy (iBT) implants. Based on the promising results of single-institution studies, and the multicentric retrospective analysis of the GEC- ESTRO Breast Cancer Working Group, second BCS and iBT became a valid alternative to MT for the management of IBTR after previous breast conserving therapy. Patient selection criteria for second BCS + iBT are mainly based on the results of retrospective series. Based SP-0260 Techniques and results of salvage brachytherapy after 2nd breast conserving surgery J. Hannoun-Levi 1 1 Antoine Lacassagne Cancer Center, Radiation Therapy, Nice, France Abstract Text Until recently, the historical and only treatment for ipsilateral breast tumor recurrence was salvage mastectomy (SM). However, based on unicentric, small and old studies, the principle of second conservative treatment (2 nd CT) was already proposed without clearly convince the breast cancer treatment professional community. Currently, it is well recognized that a randomized phase III trial comparing SM versus 2 nd CT is not conceivable. Since the last 10 years, international research groups provided mature and convincing results leading to consider 2 nd CT based on lumpectomy plus re-irradiation of the tumor bed as an acceptable salvage therapeutic option. The choice between SM versus 2 nd CT is mainly based on histopathological factors. If they lead to consider a SM, a 2 nd CT must be ruled out (idem primary breast cancer - PBC). On the other hand, in the absence of bad histopathological prognosis factors, breast size after the primary conservative treatment and the cutaneous/subcutaneous consequences of the first irradiation should be taken into account in order to discuss a 2 nd CT + re-irradiation. Indeed, regarding the published data, it is well demonstrated that, in case of 2 nd CT a re-irradiation of the tumor bed is mandatory in order to improve local control rate (idem PBC). According to the results of the propensity score-matched cohort analysis published by the GEC-ESTRO Breast Cancer Working Group, with a median follow-up of 74 months, no differences in 5-year overall survival and cumulative incidence of third breast event were noted between mastectomy and conservative treatment (88% vs 87%) and (2.3% vs 2.8%) respectively with a 5-year cumulative incidence of mastectomy of 3.1%. In terms of late side effects after 2 nd CT, the GEC-ESTRO study reported a rate of 75% of complications with less than 10% for Grade 3 and worse toxicities (9.5%). Cutaneous (24.7%) and subcutaneous fibrosis (42.1%) were the most frequent observed side effects while breast deformation, hyperpigmentation, telangiectasia, and ulceration were observed in 12.4%, 10.2%, 8.8%, and 1.8% of cases, respectively. Cosmetic results were rated as excellent (99 patients; 46.7%), good (71 patients; 33.5%), fair (27 patients; 12.7%), and poor (15 patients; 7.1%). Regarding the available techniques used for tumor bed re-irradiation, while external beam and intra-operative radiation therapy are currently under investigation, mutlicatheter interstitial brachytherapy represents the technique which provide the best oncological outcome with the longest follow-up. In case of second breast event, second conservative treatment is a validated salvage therapy. The decision- making process in patients with second breast event must be based on a full and detailed explanation of the risk and benefits of each salvage treatment in order to honestly and precisely guide the patient’s choice. Symposium: Salvage brachytherapy for breast cancer on retrospective data, patient selection criteria include: - Unicentric, parenchymal IBTR without skin involvement; - Isolated IBTR (lack of concurrent regional and distant recurrence); - IBTR size ≤ 3 cm; - Time to IBTR < 3 years. In conclusion, second BCS + iBT is a viable alternative to MT for the management of isolated, solitary, parenchymal IBTR after previous breast conserving therapy. Reirradiation with iBT may decrease the risk of second LR without significantly increasing the risk of radiation side effects. Further prospective studies are required to define the value of second BCS plus reirradiation in comparison with salvage MT, as well as with second BCS without RT.