Li Facheng, director of plastic surgery at China Academy of Medical Sciences, said that implanting silicone prosthesis is a common method for breast augmentation all over the world, and the safety is the patient's most concerned about whether the prosthesis will cause cancer. An interesting phenomenon was found through a large sample epidemiological investigation and a follow-up of 10 years. The incidence of breast cancer in patients with breast augmentation is lower than that in patients without breast augmentation. Possible reasons: 1: Patients who need breast augmentation have smaller breasts, and patients with smaller breasts are less likely to develop breast cancer than patients with larger breasts. 2. Silicone prosthesis has anticancer effect. Animal experiments show that the incidence of breast cancer in animals implanted with silicone prosthesis after breast cancer is lower than that in the control group without silicone prosthesis. In addition, the blood of women implanted with silicone prosthesis and breast augmentation can kill breast cancer cells in tissue culture. Two large epidemiological studies examined the follow-up risk of breast cancer after breast augmentation. One study was based on the implant cohort of 676 women in Alberta, Canada 1 1, and they were followed up for 13 years. The other study was conducted in Los Angeles, and the median exposure time of patients with silicone implants was 15.5 years. The conclusion of these studies is that the incidence of breast cancer in enhanced patients is lower than that in non-implanted control subjects. Some possible explanations for these unexpected findings are that women with smaller breasts may be less prone to breast cancer, or silicone may have a biological protection against breast cancer. The latter possibility is based on animal experiments, which show that the incidence of breast cancer in rats receiving silica gel implants before stimulation with proven carcinogens is reduced. The incidence of breast cancer in animals implanted with silicone breast prosthesis under breast tissue was 52.5% lower than that in the control group. In another report with similar findings, blood from women with breast augmentation killed breast cancer cells in tissue culture.