KI67 is only an indicator to reflect the proliferative activity of breast cancer cells, and it is not possible to estimate the survival period of patients directly through KI67. KI67 is one of the commonly used indicators in breast cancer pathology report, its main function is to measure the proliferation activity of cancer cells, the value is generally in the range of 0~100%, the higher the value, the higher the proliferation activity of cancer cells, which is usually used to determine the diagnostic and treatment plan of the patient, and it can’t be used to estimate the survival time directly. The prognosis of breast cancer is related to the tumor stage. Generally speaking, the five-year survival rate of early-stage breast cancer can be up to 90%, and even the ten-year survival rate of some patients with better pathological types can still be up to 90%. However, the survival rate of advanced stage patients is lower, and the general five-year survival rate is 20%.