In recent years, emerging approaches in breast cancer diagnosis and treatment have leveraged advanced molecular imaging and biomarker technologies, targeted therapies, and immunotherapy. On the diagnostic front, liquid biopsy techniques-analyzing circulating tumor DNA-enable early detection of metastasis and real-time monitoring of treatment response. Therapeutically, PARP inhibitors have shown significant efficacy in BRCA-mutated patients, while CDK4/6 inhibitors have transformed care for hormone receptor-positive subtypes. Additionally, therapeutic vaccines and novel monoclonal antibodies such as trastuzumab deruxtecan demonstrate high potency against HER2-positive tumors. Cutting-edge research into nanotechnology and theranostic platforms, which combine diagnostic and therapeutic functions in a single system, promises to reduce side effects and enhance treatment precision.