Case 18 Answer 2
This patient had known ovarian carcinoma, and the biopsy showed metastatic ovarian carcinoma, but the differential diagnosis included a primary breast cancer. The diffuse calcifications are more typical of the psammomatous calcifications seen with ovarian tumors. In fact, when primary breast tumors are the papillary type and have multiple calcifications, the pathologist may include ovarian metastasis in the differential after core biopsy.
These are not the typical pop-corn or coarse calcifications one sees with fibroadenomas. Phylloides tumors do not have typical calcifications. Papillomas do occasionally have diffuse calcifications, so this answer is possible, but less likely.
The calcifications really make the mass look echogenic on ultrasound. Hyperechogenicity is a benign ultrasound characteristic. It is important to remember that when a mass is suspicious by mammography, one cannot back away from a biopsy because of a benign ultrasound appearance.