For locally advanced or recurrent metastatic breast cancer that is resistant to systemic therapy, radiotherapy (RT) may be considered as the preferred treatment option when the lesion is unresectable, or the patient is not suitable for surgery. This study aim to evelatuate the local control of radical dose RT or new RT technique (such as patially fractionated radiation therapy, SFRT) for the locally advanced or recurrent metastatic breast cancer.

Inclusion Criteria:

• Eastern Cooperative Oncology Group (ECOG) performance status of 0-2;
• Locally advanced or recurrent metastatic breast cancer, pathologically confirmed;
• At least one extracranial measurable lesion suitable for radiotherapy;
• Signature of informed consent form.

Exclusion Criteria:

• Pregnant or lactation women;
• Severe concomitant conditions, including persistent or active infections, symptomatic congestive heart failure, unstable angina pectoris, and serious arrhythmias et al.