Abstract P1-15-06: Localized triple negative breast cancer in extremes of life
Authors: Morante Z , De la Cruz-Ku G , Pinto J , Enriquez D , Saavedra A , Luján M , Luque R , Eyzaguirre E , Fuentes H , Neciosup S , Gomez H 
Published: February 2018

Background: Triple-negative breast cancer (TNBC) in young and older patients has specific features and outcomes. While in younger patients, it is characterized by being aggressive with worse survival, in advanced ages it may have a better outcome which reasons have not yet fully elucidated. Our objective was to compare clinicopathological characteristics, treatment and survival rates between very young with elderly population diagnosed of TNBC.

Methods: We conducted a retrospective study analysis of patients with TNBC at clinical stages I-III between 2000 to 2014 at “Instituto Nacional de Enfermedades Neoplasicas”. A total of 273 medical records were reviewed, our patients were divided in very young (≤35 years) and older (≥65 years) population. The Kaplan-Meier method was conducted to compare Disease-free survival (DFS) and Overall Survival (OS) by age and chemotherapy, while Cox regression analysis assessed hazard ratios.

Results: From 273 patients with TNBC, 132 were ≤35 years, and 141 were ≥65 years. Elderly population had more obesity (13.1% vs 23.6%, p=0.03) and comorbidities (15.9% vs 46.1%, p&lt;0.001); 42 (15.4%) had antecedent of breast and/or ovarian cancer (≤35y vs. ≥65y - 18.2% vs. 12.8% - p=0.22). Younger patients were diagnosed at a higher T stage (T3:27.9% vs 11.3%, p&lt; 0.001) and N (N0 vs N1-2, 47.6% vs 34.9%, p=0.04), hence CS was higher among this group of age (IIIA: 24.2% vs 12.8%, p=0.005). Pathological features, 80.3% presented high histological grade, positive margins (p=0.008) and vascular permeation (p=0.048) were identified in a younger population. Neoadjuvant chemotherapy (NAC) (24.2% vs 12.8%, p=0.01), adjuvant chemotherapy (AC) (72.7% vs 46%, p&lt;0.001) and radiotherapy (RT) (56.8% vs 44%, p=0.03) were less received in elderly patients, while mastectomy (51.7% vs 65.1%, p=0.03) was mostly surgical technique used. There were no differences between locoregional (22.7% vs 32.6%, p=0.07) and distant (31.1% vs 39%, p=0.17) relapse rates. With a median follow-up of 8.8 years, at 5-year DFS, was better in younger patients (76% vs 60%, p=0.02), but no difference was obtained in OS (80% vs 70%, p=0.05). Chemotherapy showed to have an impact in a better DFS (HR:0.47, 95%CI: 0.27-0.83) and OS (HR: 0.53, 95%CI: 0.31-0.91, p=0.02). Indeed, at 5-year OS was 89% for young patients with CT, 78% for elderly population with CT, 64% for ≥65y without CT and 54% for young without CT.

Conclusions: Despite the differences between characteristics of young and old patients, chemotherapy plays a critical role in DFS and OS in both populations. In elderly patients, chemotherapy should be considered in order to offer better outcomes.

Citation Format: Morante Z, De la Cruz-Ku G, Pinto J, Enriquez D, Saavedra A, Luján M, Luque R, Eyzaguirre E, Fuentes H, Neciosup S, Gomez H. Localized triple negative breast cancer in extremes of life [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-15-06.