The authors analyze current approaches to diagnosing and treating breast cancer (BC) with supraclavicular and parasternal lymph node (LN) metastases. The features of metastatic BC are considered; among the supraclavicular LNs, the sentinel node is stated as being identified as anatomically most important. It is noted that when a tumor is located in the medial and central quadrants of the gland, the role of the parasternal trajectory increases since the internal mammary collector is one of the main ways of BC metastasis. The paper considers the role of radiation therapy as one of the methods that locally affect the collector involved with metastasis. It gives the results of clinical trials evaluating the efficacy and safety of treatment for metastatic BC in the supraclavicular and parasternal LNs. These patients are noted to have a high risk of undiagnosed distant metastases, even in the absence of obvious clinical signs of their presence. Combination treatment (chemotherapy, surgical treatment, and radiation therapy) is recommended in these patients. At the same time, today there is no convincing evidence confirming that it is expedient to prescribe combined treatment for the considered category of BC patients, and the role of surgical treatment for supraclavicular LN metastases has been insufficiently studied. Nevertheless, supraclavicular lymphadenectomy has been established to be a predictor for overall survival in this cohort of patients. A number of authors hold that with this in mind, BC with supraclavicular and parasternal LN metastases without signs of distant metastasis can be considered as regional and, therefore, potentially treatable.