Immune Tumor Stroma Factors and Pathologic Complete Response After Neoadjuvant Chemotherapy in Early Breast Cancer

This prospective observational cohort study investigates the relationship between immune-related tumor stroma factors and response to neoadjuvant chemotherapy (NACT) in patients with early breast cancer treated at the Institute of Oncology Ljubljana. The primary objective is to identify immune predictive markers in the tumor microenvironment that are associated with achieving pathological complete remission (pCR) after neoadjuvant chemotherapy. Tumor tissue and blood samples will be analyzed to evaluate immune-related biomarkers and their prognostic and predictive value. In addition, circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA) will be assessed in peripheral blood samples collected before initiation of treatment, in order to determine their association with immune-related tumor stroma characteristics and clinical outcomes. The study aims to improve understanding of biological mechanisms influencing treatment response and may support future personalized treatment strategies by identifying patients who are most likely to benefit from neoadjuvant chemotherapy.