Díaz-Casas SE, et al. - In this observational, descriptive, historical cohort study, researchers examined patients (n = 414) with locally advanced breast cancer treated within the National Cancer Institute Functional Breast Cancer Unit in Bogotá, Colombia, to determine the pathological response to neoadjuvant chemotherapy (NACT) according to the molecular classification of breast cancer. Luminal B HER2-negative tumors were detected in most patients. In locally advanced breast tumors, a link was found between pathological response and molecular subtype; pure HER2 and triple-negative tumors were associated with higher pathological complete response (pCR) rates. They also found a direct link between disease recurrences and the pathological response; patients who did not respond to NACT (Chevallier 3 and 4) suffered greater tumor recurrence. Patients with pCR had greater event-free survival and overall survival; statistical importance was only seen in triple-negative tumors.