Abstract
Breast cancer remains one of the most prevalent and socially significant malignancies among women worldwide. Advances in molecular biology and oncogenetics have substantially transformed approaches to the diagnosis, prognosis, and treatment of breast cancer, with a growing emphasis on personalized medicine. This review explores the molecular-genetic landscape of breast cancer, focusing on the distinctions between germline and somatic mutations, their clinical relevance, and their role in guiding individualized therapeutic strategies.The results of the literature review demonstrated that germline mutations-particularly in BRCA1and BRCA2-are strongly associated with hereditary breast cancer predisposition, influencing both risk assessment and preventive strategies. Incontrast, somatic mutations, including alterations in TP53, PIK3CA,and ESR1,play a pivotal role in tumor behavior, treatment resistance, and disease progression.Moreover, integrative molecular profilingusing next generation sequencingincorporates both germline and somatic mutation data provides a more accurate framework for clinical decision-makingin personalized therapy. Studies have shown that patients with combined profiling benefit from more precise therapeutic targeting, including PARP inhibitors, endocrine therapies, and immune checkpoint inhibitors.The integration of germline and somatic analyses represents a critical step in the realization of precision medicine, ultimately improving therapeutic outcomes and prognosis in breast cancer patients.Keywords: breast cancer, BRCA1/2, germlinesomaticmutation,next-generation sequencing, precision medicine.