Mammographic changes after excisional breast biopsy for benign disease

The purpose of this study was to establish the incidence and natural history of mammographic changes in patients within 5 years of an excisional breast biopsy.

We reviewed the records of 428 consecutive patients who had undergone excisional biopsy for benign breast disease. We recorded year by year the mammographic changes seen after surgery. Because the site of surgery was known in each patient and because follow-up imaging continued for at least 2 years after biopsy, our analysis was able to exclude interval malignancy in the area of surgery. We then applied linear regression analysis to determine trends regarding progression, stability, or regression of changes after surgery.

We evaluated 293 patients with 296 biopsies for which the initial mammographic study occurred within 5 years of surgery. Of those 293 patients, 237 (81%) underwent serial mammographic studies. Of the 293 patients studied, 146 patients (50%) showed no changes related to surgery. Of the remaining 147 patients (50%) who showed mammographic changes, the most common changes at initial mammographic follow-up were architectural distortion (98/205, 48%), skin thickening (35/205, 17%), and increased focal density (parenchymal scar) (30/205, 15%). Regression analysis showed no significant change of mammographic features in all patients during 5 years of follow-up (p > .2).

Mammographic changes after excisional breast biopsy were seen in 50% of patients. When mammographic changes were seen, they remained stable during 5 years of follow-up. Recognition of such trends during routine surveillance should facilitate the identification of changes that represent developing malignancy.