Biopsy of mammographically-detected breast lesions in a district hospital

Seventy-nine consecutive needle localization biopsies were performed for non-palpable breast lesions discovered on screening mammography over a two-and-a-half-year period in a district hospital by 15 surgeons. Malignant disease was found in 24 biopsies (30%). Eight were in situ and 16 were infiltrative carcinomas. Half the cancers met the criteria of 'minimal' carcinoma as described by Gallagher and Martin. Forty percent of women 50 years and older (20 of 50) but only 13% of women less than 50 years (4 of 29) had a carcinoma. Of thirty-two mammograms read as 'probably' benign, two (6%) were malignant pathologically. Of forty-seven mammograms considered 'probably' malignant, 22 (47%) were malignant pathologically. Abnormal calcification (38%), density (34%) or both (28%) were suspicious mammographic features. All 'minimal' invasive carcinomas were associated with calcification. Complete removal of the lesion was not achieved in three cases (3.7%) of which none showed invasive malignancy. Of the seven complications, two required treatment. Localization biopsy of non-palpable breast lesions, detected by screening mammography in a district hospital, performed by general surgeons, has produced a yield of malignancies similar to that seen in more specialized units.