Delayed diagnosis of breast cancer as a result of normal mammograms.

Review of the effects of a normal mammogram on the treatment of 36 women with palpable breast carcinomas during a two-year period showed that 17 patients had biopsies performed within two months of their normal mammograms and 19 patients had biopsies delayed for three to 24 months. Of the 17 who had biopsies within one month of a normal mammogram, three (17.6%) had extension of disease to axillary nodes. Of 19 patients whose biopsy was delayed, cancer was found in axillary nodes of 11 (57.9%). Normal mammograms should not preclude biopsy of a breast mass.