A Prospective Observational Study About Adjuvant or Neoadjuvant Chemotherapy Related Adverse Effects in Premenopausal Breast Cancer Patients

Breast cancer is one of the most common malignant tumor in women. About 60% of breast cancer patients are still in premenopausal status at the time of diagnosis in China. It is a multicenter prospective observational study. We will collect basic information, medical history, chemotherapy-related adverse reactions, and the results of hormone, blood lipid, and bone density test before, during and after adjuvant or neoadjuvant chemotherapy. The aim of the study is to evaluate the effect of chemotherapy on ovarian function and fertility and the protective effect of GnRHa. In addition, the collected information of the subjects are analyzed to provide suggestions for the relevant prevention strategy.