The objective of this systematic review is to assess the effectiveness of aggressive treatment of oligometastatic breast cancer (OMBC) on survival outcomes by conducting a meta-analysis of current available evidence.More specifically, the objectives are to identify the effectiveness of intensified multidisciplinary treatment with aggressive locoregional therapies on survival time, five-year survival rates and disease free survival. The population is adult women (18 years and over) with OMBC defined as single or few (five or less) metastases limited to a single organ and the comparative group is conventional palliative treatment aimed at disease control. Secondary objectives to be assessed will be adverse outcomes associated with intensified treatment regimes.