Clinical Research Directory

Inclusion Criteria: 1. Patients diagnosed with breast cancer by histopathology; 2. Age between 20 and 70 years old; 3. The first diagnosis time is between 2010 and 2020; 4. Complete diagnosis and treatment information, including basic information, breast cancer diagnosis, surgery, recurrence diagnosis data (including the diagnosis of the metastasis sites), anti-tumor treatment data, bone health and bone metastasis-related diagnosis and treatment data, etc.; 5. Sufficient available follow-up information. Exclusion Criteria: 1. Missing important basic information (including initial and recurrent pathology, stage, pathological grade and time, surgery time, and drug treatment); 2. With distant metastasis at the initial diagnosis; 3. Patients with autoimmune diseases or aggressive viral infections (such as HIV or hepatitis); 4. Other malignant tumors; 5. Unclear information about distant metastasis.