Cancer is a complex cellular disease caused by multiple factors via genetic mutations (hereditary or somatic) or environmental factors. The emerging omics technologies, including genomics, epigenomics, transcriptomics, proteomics, metabolomics, and interactomics, are increasingly being used for cancer research and personalized medicine; they have provided new opportunities in the molecular analysis of human cancer with unprecedented speed and detail. The omic approach has brought powerful ability to screen cancer cells at different levels from gene to metabolite and to search for novel drug targets, expounding the drug mechanism of action, identifying adverse effects in unexpected interaction, validating current drug targets, exploring potential applications for novel drugs, and enabling the translation from bench to bedside. As a clinical research tool, the neoadjuvant approach in breast cancer is the perfect setting for individualization of treatment based on clinical, pathological, image-guided, or molecular assessment, based on the omics techniques of tumors during treatment; neoadjuvant treatment offers the ability to discern treatment effect in vivo and may allow smaller trials targeting specific breast cancer subtypes.