Características clínico-patológicas de pacientes con cáncer de mama operable HER2_low tratadas con quimioterapia neoadyuvante

Abstract

Objectives: To evaluate the clinical pathological characteristics of patients with operable Her2_low breast cancer treated with neoadjuvant chemotherapy and to identify clinicopathological variables related to survival. Methods: Observational, retrospective study in patients with operable Her2-negative breast cancer (Her2_low and Her2_zero) treated with neoadjuvant chemotherapy at Clínica Vida (Medellín) between 2013-2016. Clinical and pathological characteristics, response rates are described, and disease-free survival and overall survival were estimated between the Her2_low and Her2_zero subgroups. Results: 185 Her2_negative operable breast cancer patients treated with neoadjuvant chemotherapy were included. 80 patients (43.2%) were Her2_low subtypes, of these, 72% were luminal/Her2_low subtypes. There were no significant differences between stage T, stage N, histological grade, hormone receptor status between the Her2_zero Vs Her2_low groups. The pathologic complete response rate was similar between the Her2_low Vs Her2_zero subgroups. With a median follow-up of 79.6 months, DFS and OS are similar between subgroups of the Her2-negative population. Her2_low patients without progesterone receptor expression and ypN+ disease were associated with higher mortality rates. Conclusions: Her2-negative breast cancer subtype Her2_low appears to have a similar clinical course to the Her2-negative (0) population treated with neoadjuvant chemotherapy. Residual ypN+ disease and progesterone receptor expression have prognostic value in Her2_low breast cancer treated with neoadjuvant chemotherapy.