Molecular pathways of common breast cancer metastases and the distinguishing features of triple-negative breast cancer

Abstract

Breast cancer is the most common type of female cancer in Turkey, and metastasis is the most important cause of death, as in other solid organ cancers. Triple-negative tumors constitute 15-20% of breast cancer patients. Within three years after the development of the primary tumor, the tumor spreads to other organs. Breast cancer tends to spread to distant organs, such as bone, liver, brain, lung, and adrenal gland, either through regional lymph nodes or vascular channels. This condition, defined as the tendency to metastasize to specific organs, is called organotropism. Triple-negative breast cancer is a heterogeneous breast cancer subtype showing organotropism for the brain and the lungs. Identifying the molecular changes that may cause tropism for various regions and organs in non-metastatic tumors at the time of diagnosis is vital to developing targeted therapies and achieving longer overall and disease-free survival. In this review, we aimed to summarize the pathogenesis of breast cancer metastasis, the molecular changes involved in the metastatic process, and organotropism, as well as to emphasize the distinguishing features of triple-negative breast cancer in terms of metastatic organotropism.