Breast cancer remains one of the most prevalent oncological diseases worldwide and continues to be a leading cause of cancer-related mortality among women. Among its molecular subtypes, luminal B breast cancer is distinguished by higher proliferative activity, partial resistance to endocrine therapy, and a more aggressive clinical course compared to luminal A subtype. The present study aimed to evaluate the effectiveness of modern multimodal treatment strategies in patients with luminal B breast cancer. A comprehensive clinical and immunohistochemical analysis was performed, and treatment outcomes were assessed using survival indicators and response criteria. The results demonstrated that combined therapy, including endocrine therapy, chemotherapy, and targeted therapy, significantly improves treatment response, reduces recurrence rates, and prolongs survival. These findings confirm the importance of individualized treatment strategies based on tumor biology and molecular characteristics.

breast cancer, luminal B subtype, endocrine therapy, chemotherapy, targeted therapy, HER2, Ki-67

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