Breast cancer, the most common type of cancer among women in the western world, affects approximately one out of every eight women over their lifetime. In recognition of the high invasiveness of surgical excision and severe side effects of chemical and radiation therapies, increasing efforts are made to seek minimally invasive modalities with fewer side effects. Nanoparticles (<100 nm in size) have shown promising capabilities for delivering targeted therapeutic drugs to cancer cells and confining the treatment mainly within tumors. Additionally, some nanoparticles exhibit distinct properties, such as conversion of photonic energy into heat, and these properties enable eradication of cancer cells. In this review, current utilization of nanostructures for cancer therapy, especially in minimally invasive therapy, is summarized with a particular interest in breast cancer.