A Multicenter, Randomized Clinical Trail Evaluate Effectiveness and Security of Capecitabine or Endocrinotherapy as a Maintenance Therapy Regimen After the 1st-line Chemotherapy With Capecitabine Combine Regimen in Hormone Receptor Positive and HER2 Negative Metastatic Breast Cancer(Overstep)

A Multicenter, Randomized Clinical Trail Evaluate Effectiveness and Security of Capecitabine or Endocrinotherapy as a Maintenance Therapy Regimen After the 1st-line Chemotherapy With Capecitabine Combine Regimen in Hormone Receptor Positive and HER2 Negative Metastatic Breast Cancer(Overstep)

A multi-sites study about the efficacy of sequential monotherapy: Capecitabine vs. endocrine therapy, in metastatic breast cancer patients with HR-positive & HER2-negative after capecitabine-base chemotherapy.

capecitabine-base chemotherapy must be first-line chemotherapy.

Inclusion Criteria:

• Signed informed consent
• The age is Above 18 years of age, <70 years old
• HR-positive & HER2-negative
• Metastatic breast cancer,incurable.
• No prior chemotherapy for metastatic recurrence, if there is disease progression within 6 months after the end of the adjuvant chemotherapy, adjuvant chemotherapy as first-line treatment for metastatic lesions
• Eastern Cooperative Oncology Group performance status (ECOG PS)=0~1
• The basic function of normal bone marrow
• Functions of liver and kidney is normal
• Expectation of life is more than 3 months
• Agreed to take contraceptive measures during treatment

Exclusion Criteria:

• Previous toxicity was not recovered to 0-1 degrees
• Central nervous system metastasis
• Pregnancy or lactation
• There are uncontrolled infection, myocardial infarction, thrombosis, etc.
• There are uncontrolled chronic diseases such as diabetes, hypertension, peptic ulcer, chronic hepatitis, mental disease;
• Researchers believe that is not suitable for the study
• Patients with other malignant tumor history, except the healed skin basal cell carcinoma and carcinoma of uterine cervix;
• Bilateral breast cancer