Breast cancer is the most common form of cancer among women in the United States and is second only to lung cancer as the cause of cancer-related death;in 2007, more than 200,000 new cases of breast cancer were diagnosed and approximately 40,000 women died.  The five-year survival rate for breast cancer is about 95% if the cancer has not spread at the time of diagnosis;hence early diagnostics is vital.  One of the important challenges is blood-based, low cost detection of breast cancers, especially for very young women wherein mammography is not reliable.  Actually, availability of low cost, blood based breast cancer detection will drastically increase efficiency of detection of BC for women of all ages.  Ten- to twenty-fold lower cost of blood-based modalities will be a strong selling point in comparison to current imaging modalities.  This project focuses on increase of statistics of cohort on which the validation of our method was performed.  We expect to reach the 98% sensitivity and 96% specificity.  PUBLIC HEALTH RELEVANCE: Breast cancer is the most common form of cancer among women in the United States.  The five-year survival rate for breast cancer is about 95% if the cancer has not spread at the time of diagnosis;hence early diagnostics is vital.  Important challenge is detection of breast cancers in younger women, because they often occur at a relatively young age and are difficult to detect by both mammography and MRI.  However, because of relatively low prevalence, the method with sensitivity/specificity of about 98% needs to be developed.  We propose the additional validation of our blood-based tests, which already achieved the 95% sensitivity/specificity.