在欧美国家,女性乳腺癌是仅次于肺癌的第二大死因。在美国,1973～1976年每年有10万人患乳腺癌,每年有3万人死于该病。1990年全年约有15万新发病例,有4.4万人死亡。1997年全美国新检出乳腺癌181600例,年内死于乳腺癌的病人数达44190人[1]。在20世纪末的美国,如果妇女能够活到90 In Europe and the United States, female breast cancer is the second leading cause of death after lung cancer. In the United States, 100,000 people have breast cancer every year from 1973 to 1976, and 30,000 people die each year from the disease. In the whole year of 1990, there were about 150,000 new cases and 44,000 people died. In 1997, 181600 new cases of breast cancer were detected in the United States. The number of patients who died of breast cancer during the year reached 44,190 [1]. In the United States at the end of the 20th century, if women were able to live to 90