Surgery for nonpalpable breast lesions.

Nonpalpable lesions detected on mammograms were localized in 475 women between 1976 and 1988 by means of the spot method. A malignant neoplasm was noted in 149 patients (31%), including 69 (33%) of 206 with clusters of microcalcifications, 16 (41%) of 39 with calcifications associated with densities and 64 (28%) of 230 with nonpalpable masses. Infiltrating lesions were present in 89 (60%) of 149 patients.