Breast biopsy for nonpalpable lesions: a worthwhile endeavor?

The purpose of this study was to determine our yield of carcinoma in patients with a nonpalpable mammographic abnormality and to identify which mammographic criteria will most likely yield a positive biopsy. We conducted a review of all patients with nonpalpable mammographic abnormality who underwent needle-localized breast biopsy at our institution from 1988 to 1991. Charts of 295 patients who underwent 332 needle-localized breast biopsy were reviewed for age, family history, cancer history, mammographic findings, operative time, volume of excised breast tissue, and histology. Mammographic abnormalities were categorized as suspicious (clustered) microcalcification, stellate mass, ill-defined mass, well-circumscribed mass, developing density, or asymmetric density. The overall yield of cancer positive biopsies was 48 of 332 (14.5%). The frequency of diagnosed cancers was DCIS (8), LCIS (1), Stage I (31) and Stage II (8). The frequency that each single mammographic criteria resulted in a cancer diagnosis was: suspicious calcification (12%), stellate mass (22%), ill-defined mass (14%), well-circumscribed mass (11%), developing density (9%) and asymmetric density (0%). However, patients with both a stellate mass and microcalcifications formed the highest risk subgroup, with cancer detected 66 per cent of the time (P = 0.03).