Multidisciplinary shared decision making of fertility preservation in Young womenwith Breast Cancer (MYBC): A Pragmatic stepped wedge cluster randomised trial

Inclusion Criteria:

• Women aged 19 to 40 years old
• A person diagnosed with breast cancer by biopsy
• Those who don't have evidence of distant metastasis
• Eastern Cooperative Oncology Group(ECOG) performance status: 0-2 score
• Before registering for clinical trials, chemotherapy, radiation therapy, anti-hormone therapy, immunotherapy, and surgery are not performed
• A person who has fully understood and listened to the explanation of this clinical trial and then gave written consent

Exclusion Criteria:

• Histologically, a person diagnosed with follicular or sarcoma
• Those with a history of breast cancer (including recurrent breast cancer)
• A person diagnosed with another cancer before breast cancer
• A person diagnosed with metastatic breast cancer
• A person who has a mental illness and has a hard time understanding clinical trials
• Those who plan to conduct follow-up observation elsewhere(to change of hometowm)
• Menopausal factors without menstruation after more than a year from the last menstrual date
• A pregnant woman
• Inappropriate for participation in clinical trials