Abstract P1-09-04: Comparison of length and quality of life (QoL) and the side effects of therapy between breast conserving surgery with intraoperative radiotherapy (TARGIT-IORT) versus mastectomy for in-breast-recurrence of breast cancer
Authors: Kolberg Hans-Christian , Niesing Helena , Vaidya Jayant S , Akpolat-Basci Leyla , Maguz Abdrhman , Hoffmann Oliver , Lövey György , Stephanou Miltiades , Kolberg-Liedtke Cornelia 
Published: March 2023

Abstract
Background: Mastectomy is the treatment recommended by most national and international guidelines for in-breast-recurrence of breast cancer after breast conserving surgery (BCS) and external beam radiation therapy (EBRT). In selected cases it is possible to preserve the breast if TARGIT-IORT can be given during the second lumpectomy. We present a comparative analysis of overall survival, QoL and side effects. Methods: We identified patients who had local recurrence of breast cancer after BCS and EBRT in our prospectively maintained database. Patients were included if they had undergone either a mastectomy or BCS along with TARGIT-IORT. Patients with distant disease were excluded. Identified patients were contacted and offered participation in a prospective QoL-analysis using the BREAST-Q questionnaire. The cohorts were compared for confounding parameters, overall survival, side effects, physical, sexual and psychosocial wellbeing and satisfaction with the surgical result. Results: 36 patients treated for local recurrence were included in this analysis, 21 had received a mastectomy and 16 patients had chosen to preserve their breast and after interdisciplinary tumor board decision received BCS and TARGIT-IORT. Mean follow-up was 12.8 years since primary diagnosis and 4.2 years since recurrence. There were no significant differences between both groups regarding age, ER, PR, HER2neu, tumor size or nodal status at primary diagnosis or at recurrence and the distribution of invasive versus non-invasive recurrences. 1 patient in the BCT and TARGIT-IORT group (6.7%) and 3 patients in the mastectomy group (14.3%) died during follow up. Overall survival was numerically longer for BCS and TARGIT-IORT either calculated from primary diagnosis (median 18 years versus 8 years) or from recurrence (median 5.1 years versus 3.2 years). The numbers were too small for formal statistical analysis. No patient had another local recurrence of breast cancer during follow-up. 12 patients in the mastectomy group and 10 patients in the BCS and IORT group returned the BREAST-Q questionnaire. Psychosocial wellbeing, sexual wellbeing and satisfaction with the surgeon did not differ between both groups. Physical wellbeing was significantly superior for those whose breast could be preserved (median score for BCS and TARGIT-IORT group was 91 (71-100) vs. 66 (14-100) for the mastectomy group, p-value = 0.021). Whereas most side effects were comparable and showed no significant differences, patient-reported incidence and severity of lymphedema of the arm on the side of surgery was significantly worse in the mastectomy group (p=0.007). Conclusion: Many patients who have local recurrence of breast cancer are reluctant to lose their breast. We found that preserving the breast by use of TARGIT-IORT was safe with no re-recurrence and no detriment to overall survival. This is necessarily a small series, because local recurrence is rare, yet, this novel approach led to a statistically significant improvement in physical wellbeing and incidence and severity of lymphedema. These data increase the confidence in offering breast preservation and TARGIT-IORT for surgery of in-breast-recurrence of breast cancer.
Citation Format: Hans-Christian Kolberg, Helena Niesing, Jayant S Vaidya, Leyla Akpolat-Basci, Abdrhman Maguz, Oliver Hoffmann, György Lövey, Miltiades Stephanou, Cornelia Kolberg-Liedtke. Comparison of length and quality of life (QoL) and the side effects of therapy between breast conserving surgery with intraoperative radiotherapy (TARGIT-IORT) versus mastectomy for in-breast-recurrence of breast cancer [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P1-09-04.