Preoperative hormone sensitivity test as a tool for personalizing systemic therapy in breast cancer patients

Breast cancer is a heterogeneous disease. Luminal breast cancers account for up to 75 % of all breast cancer cases. However, even within this large group, there are significant differences in the course of the disease and therapeutic response to endocrine therapy, which dictates the need to explore and consider all available biological characteristics of the malignant tumor in optimal treatment decision making. Currently, adjuvant therapy for patients with breast cancer is mainly based on clinical and pathological factors. Multigene signatures that would help in personalizing systemic therapy are currently not available in our country. Therefore, there is a constant search for tools that could effectively predict the effectiveness of endocrine therapy at the early stages of treatment. One of such tools is a preoperative hormone sensitivity test.