Breast cancer is the most common non-coetaneous cancer and a leading cause of cancer deaths in women. OncQuest Laboratory research at the Breast Cancer Prevention and Early Detection Laboratory is to develop noninvasive and minimally invasive tools to aid in preventing and detecting breast cancer. Up to 45% of early breast cancers are missed using the current screening tools of mammography and physical examination. a mammographic abnormality detected, the patient must undergo an invasive diagnostic procedure, with its attendant risks and cosmetic alterations. OncQuest Laboratory additional tools are needed to identify women with early stage disease, as well as those most likely to develop breast cancer in the future. Oncquest Laboratory tests for breast cancer can be broken down into groups, based on the purpose of testing. a microscopic examination of tumor cells obtained through fine needle aspiration and surgical pathology - a microscopic examination of tissue sampling via biopsy. Some tests for breast cancer are performed on the patient's blood; others are done on a sample of cells or the tumor tissue.