Abstract PO3-07-12: Effect of neoadjuvant chemotherapy on peritumoral edema in early stage breast cancer and its prognostic value

Abstract

Abstract Objectives: We aimed to evaluate the effect of neoadjuvant chemotherapy (NAC) on peritumoral edema (PE) and its prognostic value in operable breast cancer. Materials & Methods: This retrospective study included 128 cT1-4N0-3M0 breast cancer patients who underwent contrast-enhanced magnetic resonance imaging (MRI) of the breast before and after anthracycline- and/or taxane-based NAC, followed by curative surgery at our hospital, between 2006 and 2016. T2-weighted MRI revealed PE, and PE before NAC (pre-PE) and PE after NAC (residual PE) were evaluated. The correlation between the presence or absence of PE and relapse-free survival was evaluated using a log-rank test and multivariable Cox regression analysis. The risk of recurrence was stratified according to the residual cancer burden (RCB). Results: Pre-PE was observed in 64 out of 128 patients (50%). Among 64 patients with pre-PE-positive breast cancer, residual PE was observed in 21 (32.8%). In the log-rank test, breast cancer with residual PE had a poorer prognosis than breast cancer with PE that had disappeared (p < 0.0001). In the multivariable Cox regression analysis, residual PE was a significant factor of poor prognosis (RR, 20.5; 95% confidence interval, 5.3–108.2; p < 0.0001). Regarding RCB stratification, compared to patients with breast cancer with disappeared PE, those with breast cancer with residual PE exhibited significantly poor prognosis in class II and class III (p = 0.006, 0.02). Conclusion: In breast cancer with PE, residual PE after NAC is a significant factor related to poor prognosis. Effect of neoadjuvant chemotherapy on peritumoral edema in patients with breast cancer and its clinical significance XX XX Citation Format: Hideo Shigematsu, Mutsumi Fujimoto, Yoshie Kobayashi, Tomoyuki Yoshiyama, Noriaki Matsuura, Daisuke Komoto, Kazuya Kuraoka. Effect of neoadjuvant chemotherapy on peritumoral edema in early stage breast cancer and its prognostic value [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-07-12.