Local Therapy for ER/PR-positive Oligometastatic Breast Cancer

Inclusion Criteria

• •Female sex
• •≥ 18 years of age
• •Histologically confirmed invasive breast cancer, with oligometastatic disease defined as one of the following criteria: 1) One to four bone lesions; 2) One to four lung and/ or hepatic lesions; 3) Distant metastasis limited to ipsilateral cervical lymph nodes; 4) Distant metastasis limited to contralateral axillary lymph nodes
• •Oligometastatic sites amenable to treatment with a local therapy modality, including surgical resection, stereotactic radiotherapy, or radiofrequency ablation
• •Estrogen receptor-positive and/ or progesterone receptor-positive breast cancer
• •Partial response or stable disease after at least six months of systemic therapy for breast cancer
• •Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1
• •Measurable or non-measuble disease according to Response Evaluation Criteria in Solid Tumors (RECIST) 1.1
• •Life expectancy of at least 12 weeks
• •For women in childbearing age, negative pregnancy test until 21 days before the date of study enrollment.
• •Signed informed consent form
• •Disposition and aptitude to fulfill the study protocol during the study duration