The changing mammogram. A primary indication for needle localization biopsy.

Screening mammography results in improved detection and survival for women with breast cancer. Interval mammographic changes may be one of the major indications for biopsy. Four hundred fifty-two needle localization biopsies carried out for microcalcifications, mass, asymmetric density, or a combination of calcifications with mass or asymmetric density detected 95 cancers (21%). Interval mammographic changes detected 35 cases (17.9%). Invasive cancers constituted 51% of the initial group but only 34% of the cancers detected because of interval change. Benign breast disease occurred in 160 of 195 women who had undergone biopsy because of interval changes. These changes continued into the postmenopausal period. Hyperplasia and/or atypia was found in 57 (35%) of 160 of the interval group. Interval mammographic abnormalities detect significant pathologic changes in the breast and should be considered a major indication for breast biopsy.