In order to understand the mechanism of human breast cancer we use the growth rates of clonal expansion of intermediate cells and mutation rates as parameters and build two-six stage models to fit the age-specific incidence of breast cancers in the surveillance, epidemiology, and end results (SEER) registry. We propose four types of different mechanisms for the human breast cancer and test those mechanisms by Chi-square test. Our results suggest that loss of functions of instability genes is an early event in the tumorigenesis, which is useful for early diagnosis of breast cancer. The clonal e...
