Is needle-directed breast biopsy overused?

We undertook this study of needle-localized breast biopsy-a frequently done surgical procedure-to examine current practice patterns and to determine if the technique is overused in any group of patients. From a retrospective review of medical records of all patients who had needle-localized breast biopsy at a teaching hospital between June 1, 1988, and October 31, 1990, we found that a total of 125 were done: 24 biopsy specimens showed malignancy (19%). Mammographic indications for biopsy were microcalcification (n = 62, or 50%), mass or density (n = 60, or 48%) and mass and calcifications (n = 3, or 2%). Indications for biopsy in patients with cancer were microcalcification (14 patients) and mass or density (10 patients). The incidence of malignancy increased with age. In patients younger than 40 years, no biopsy showed malignancy. Only 2 of 30 biopsies done in patients younger than 50 showed cancer (7%). Breast cancer was most frequently discovered in patients in the seventh and eighth decades of life, and this group accounted for 75% of 'positive' biopsies. Needle-localized breast biopsy is a useful technique in the early diagnosis of breast cancer. Although indications for the procedure should remain liberal, in women younger than 50, the percentage of biopsies that reveal malignancy is low.