MG, US, and post-surgical pathology results from a 43-year-old patient with a lump in her right breast. (A) Craniocaudal and mediolateral oblique views of the molybdenum target MG of the right breast. MG were unsatisfactory (BI-RADS category 0) because of the dense gland structure. (B) MG of the left breast of the same patient. (C) US detected an irregular hypoechoic lesion with clear boundaries. (D) Intra-operative pathology revealed an invasive ductal carcinoma (HE staining, ×100). This is a typical example of a missed diagnosis of breast disease by MG.