乳腺癌是危害妇女健康的主要恶性肿瘤[1]。近年来世界范围内,乳腺癌发病率不断上升,尤其是在一些欧美发达国家,严重危害了广大妇女的身心健康乃至剥夺了其生命。虽然,我国是乳腺癌相对低发的国家,但近20年,像北京、上海、天津、南京等一些大城市,乳腺癌的发病率也在不断地增加[2]。全球每年大概诊断出130万人患有乳腺癌,而大约40万患者死于该癌症[3]。迄今为止,乳腺癌的病因尚未完全阐明,有大约50%的乳腺癌发病原因无法解释[4],但国内外诸多流行病学专家、学 Breast cancer is a major malignancy that affects women’s health [1]. In recent years, the worldwide incidence of breast cancer has been on the rise, especially in some developed countries in Europe and the United States, which has seriously endanger the physical and psychological health of the vast number of women and even deprive their lives. Although China is a country with relatively low incidence of breast cancer, the incidence of breast cancer has been continuously increasing in recent 20 years in some big cities like Beijing, Shanghai, Tianjin and Nanjing [2]. Approximately 1.3 million people worldwide are diagnosed with breast cancer each year, while about 400,000 people die of the cancer [3]. So far, the cause of breast cancer has not been fully elucidated, about 50% of the causes of breast cancer can not be explained [4], but many epidemiologists at home and abroad, learning