Stability of Malignant Breast Microcalcifications

Purpose: To determine the frequency of stability in malignant microcalcifications and its relationship to specific histologic diagnoses.

Materials And Methods: During a 34-month period, microcalcifications were proved malignant in 182 patients referred for needle-guided biopsy. In 105 patients, the mammograms were compared with one or more than one previous mammogram. These patients were classified on the basis of interval change in two groups: those with stable and those with increasing or new microcalcifications. The histologic diagnoses were reviewed.

Results: Microcalcifications were stable for 8-63 months (mean, 25.4 months) in 26 patients (24.8%), only three (12%) of whom had invasive ductal carcinoma, which was found in 29 (37%) of the 79 patients with increasing or new microcalcifications.

Conclusion: The odds for presence of invasive ductal carcinoma are statistically significantly lower (P < .025) among patients with stable microcalcifications than among those with increasing or new microcalcifications. Stability of indeterminate or suspicious microcalcifications is unreliable for exclusion of a diagnosis of malignancy.