The key to surviving breast cancer is early detection and treatment. Current technologies rely heavily on imaging of the breast and have their limitations. There is a need for a more accurate screening test which can detect the cancer at a cellular level and before metastasis. There have been extensive studies into markers for breast cancer including protein and micro RNA biomarkers, but to date, these have not been truly successful. An upcoming field of interest is the association between breast cancer and lipids, which is documented in the literature. Studies have found there is an alteration in specific lipid species in tissue of breast cancer compared to healthy tissue and similar results have been found in blood. BCAL Diagnostics is working with the University of Kentucky to develop a process by which novel lipid biomarkers for breast cancer, found in the blood, could be used as the basis of a breast cancer-screening test. Blood plasma contains different extracellular vesicles (including microvesicles and exosomes), which are shed from the cells of most tissues. Exosomes are derived from the endosomal membrane of cells, and contain a variety of proteins, lipids, mRNA and micro RNAs. There is now considerable interest in the role of exosomes in immunology and cancer biology. Our preliminary data, from the plasma of 50 women confirmed to have ductal invasive breast carcinoma and 50 disease- free controls, indicate that the lipid composition of exosomes differs between healthy individuals, and patients with the disease. The data from this study confirmed significant discrimination between the two groups with an Area Under the Curve (AUC) of 93% when using 14 lipid discriminators. This indicates a final sensitivity and specificity of 90%. Such distinction may be developed into a sensitive, specific, minimally invasive, and low-cost diagnostic test for breast cancer.