Molecular Mechanisms of Lymphatic Metastasis in Breast Cancer: An Updated Review

Breast cancer is the most prevalent malignancy among women and a leading cause of morbidity and mortality worldwide. Metastasis-the dissemination of tumor cells to distant organs-is the primary driver of breast cancer-related deaths, often leading to organ dysfunction and treatment resistance. While sentinel lymph nodes are the initial site of metastasis, the molecular mechanisms driving lymphatic spread are still not well understood. Multifarious questions remain on the role, requirement, and significance of the lymphatic system in the context of the distant metastasis of breast cancer. To address these questions, this review explores the recent advancements achieved in studies related to the molecular processes behind lymphatic metastasis in breast cancer, highlighting the tumor microenvironment's role in supporting circulating tumor cells. We also examine the key molecular pathways involved in metastatic progression by analyzing the cellular, genetic, and physiological factors that drive lymphatic metastasis. The insights gained may contribute to the development of new therapeutic approaches to prevent or mitigate breast cancer metastasis.