Abstract:As a breakthrough of precision medicine, intratumor heterogeneity is a research hotspot and is correlated to tumorigenesis, metastasis and resistance to therapies. In breast cancer, evidence of intratumor heterogeneity has been documented by numerous studies and it is the main obstacle to find ideal tumor markers and personalized medicine. Further analysis including the feature and generation mechanism of intratumor heterogeneity and the methods to assessment intratumor heterogeneity in the clinic are the key to cancer precision medicine.

Key words:Breast neoplasms,Intra-tumor heterogeneity,Precision medicine