Management of microcalcifications developing at the lumpectomy bed after conservative surgery and radiation therapy

The purpose of our study was to determine whether the mammographic features (morphology and distribution) of new microcalcifications that develop in women treated with lumpectomy and radiation therapy can allow differentiation of benign changes from recurrent neoplasm.

A retrospective review of mammograms of 402 patients who were treated with conservative surgery and radiation therapy between 1987 and 2005 revealed 68 cases of new calcifications (in 66 patients) with follow-up (n = 55) or biopsy (n = 13) results. Analysis included the time between completion of radiation therapy and the appearance of calcifications; location of calcifications relative to the site of the original lesion; the morphology and distribution of calcifications; and changes in number, density, morphology, and rate of change of calcifications.

The median rate of development after lumpectomy was 24 months (range, 6-84 months) for benign and 52 months (range, 20-90 months) for malignant calcifications. In 63 cases (93%), the new calcifications developed in the same quadrant as the primary tumor. None of the calcifications initially interpreted as BI-RADS category 2 (n = 40/68; 59%) and category 3 (n = 19/68; 28%) represented recurrent disease. Nine (13%) of 68 calcifications were initially classified as BI-RADS category 4 or 5; six (67%) of the nine were malignant and three (33%) were benign at biopsy.

Newly occurring calcifications in the treated breast are usually benign, and they can be managed conservatively in many cases by using morphology and pattern of distribution as a guide.