Histologic specimens from excisional biopsy in 22 subjects with malignant breast masses were assessed and compared to OA imaging that was done prior to both core biopsy and excision. ER, PR, and HER2 status from the excisional biopsy histology were used to approximate the molecular subtype. The three internal OA findings (density of vascularity, relative blood oxygen saturation, and total blood accumulation) and two external OA findings (total blood and peri-tumoral radiating vessels) were assigned qualitative scores from 0-5. The internal scores were summed to obtain an OA internal total score and the external scores were summed to obtain an OA external total score. The total internal and external scores were summed to obtain an OA total score.  The mean total internal, mean total external, and mean total scores were then compared to molecular subtype of carcinoma.