In any medical center around the world, there is a problem of breast cancer patients who request to have the opposite normal breast removed along with the surgery (medically known as prophylactic resection), however, in the hands of doctors, there is also a great doubt because they do not know if prophylactic resection reduces the patient’s risk of developing cancer or if prophylactic resection improves the patient’s survival, and so, at the The preventive resection was thus performed in various breast centers around the world at the strong request of patients, although not many, yet it did happen. In particular, in 2013, Angelina Jolie had both of her breasts removed to prevent breast cancer, sparking a lively worldwide debate about prophylactic excision. Although there is still much controversy as to whether patients with unilateral breast cancer should undergo contralateral prophylactic mastectomy, the number of clinical cases treated with contralateral prophylactic mastectomy continues to grow and studies have been reported, yet the results vary from one to the other! Therefore, Dr. Julie A. Margenthaler, a researcher from the Alvin J. Siteman Cancer Center at Barnes-Jewish Hospital and the University of Washington School of Medicine, conducted a Meta-analysis of the current literature on contralateral prophylactic mastectomy for patients with unilateral breast cancer to evaluate whether contralateral prophylactic mastectomy for patients with unilateral breast cancer This study is the first study to evaluate the effectiveness of unilateral prophylactic mastectomy in patients with unilateral breast cancer. The study is the first meta-analysis to evaluate the prognosis of patients with unilateral breast cancer after contralateral prophylactic mastectomy, and the results were published in the June 2014 issue of the American Journal Ann Surg. The researchers collected a total of 14 relevant studies published before March 2012 by searching five databases, which were tightly designed and of high quality. After analysis, the authors found that patients who underwent contralateral prophylactic mastectomy had higher overall survival (OS, RR = 1.09) and lower breast cancer mortality (BCM, RR = 0.69) than those who did not undergo contralateral prophylactic mastectomy, but the incidence of heterozygous contralateral breast cancer was not significantly lower; patients with a family history of breast cancer or who carried a BRCA gene mutation were more likely to have a higher incidence of heterozygous contralateral breast cancer than those who underwent contralateral prophylactic mastectomy. Patients with a family history of breast cancer or carrying a BRCA gene mutation had a significantly lower relative and absolute risk of developing heterochronic breast cancer after contralateral prophylactic mastectomy, but there was no significant difference in overall survival and breast cancer death rates. These findings suggest that in patients with high breast cancer risk (those with a family history of breast cancer and those carrying the BRCA gene), undergoing contralateral prophylactic mastectomy significantly reduces the incidence of heterozygous breast cancer, but does not improve the survival rate of these patients, in short, the survival time is the same for these high risk patients if they undergo prophylactic mastectomy together with this surgery and wait until the contralateral side develops. The difference is that waiting for surgery after the onset of disease may increase the number of treatment procedures (requiring a second surgery, chemotherapy, radiotherapy, endocrine therapy, etc.), while this prophylactic resection may lead to overtreatment (because although it is a high-risk group, it does not mean that the contralateral side will develop cancer). The analysis also found that in the general population, the finding that patients who underwent contralateral prophylactic mastectomy had a better prognosis compared with those who did not undergo contralateral prophylactic mastectomy does not prove that contralateral prophylactic mastectomy in the general population does not reduce the incidence of heterochronous breast cancer. Therefore, the researchers concluded that contralateral prophylactic mastectomy is associated with a reduced risk of heterozygous breast cancer in high-risk groups, but does not improve survival in patients with a higher family/genetic risk, so if patients are proven to be at high risk (BRAC1 and BRAC2 mutations detected by genetic testing), contralateral prophylactic mastectomy may be considered to simplify the treatment process in the future, but it does not mean that it is necessary. It does not mean that resection is necessary, as it does not improve survival time. Contralateral prophylactic mastectomy is not recommended for patients with unilateral breast cancer whose family/genetic risk is unknown.