A comprehensive review of de novo oligometastatic breast cancer: Current treatment options, surgical outcomes, and systemic therapy.

De novo metastatic breast cancer (dnMBC) represents a biologically diverse malignancy, manifesting with variable clinical trajectories. While systemic therapy (ST) constitutes the primary modality in its treatment paradigm, the role of locoregional interventions such as surgery and radiotherapy is increasingly being explored, particularly in patients with oligometastatic breast cancer. This subset, defined by a limited number of metastatic sites, may follow a less aggressive course and thus become candidates for intensified multimodal therapeutic strategies. Although locoregional treatment (LRT) alone does not offer a curative outcome in the metastatic setting, it can provide meaningful benefits in terms of local disease control, palliation of symptoms, and overall improvement in quality of life. The survival benefit associated with surgical removal of the primary tumor in dnMBC remains a subject of ongoing investigation, with current evidence yielding inconclusive results regarding its effect on overall survival. Nevertheless, a range of individual parameters including the biological characteristics of the tumor, the extent of metastatic spread, response to ST, and the patient's overall functional status play a decisive role in guiding therapeutic choices. Employing a multidisciplinary framework is crucial to appropriately select patients who are most likely to benefit from the addition of LRT as part of an integrated treatment approach.