Atypical ductal hyperplasia at margin of breast biopsy - Is re-excision indicated?

Background: Atypical duct hyperplasia (ADH) observed during core needle biopsy is associated with a high rate of cancer upon excision. Controversy exists regarding the need to re-excise ADH involving a margin. The purpose of this study was to determine the rate of residual pathology in patients that underwent re-excision for ADH involving the margin. Methods: In a retrospective review of the pathology database from 1 January 2000 to 1 June 2006, we identified 44 lumpectomy specimens with ADH involving the margin; 24 patients (55%) had a re-excision. Slides were reviewed to verify the diagnosis of ADH near the margin and the presence of residual disease on re-excision associated with the biopsy cavity. Results: Patients had pure ADH (15, 63%), ADH and ductal carcinoma in situ (DCIS) (7, 29%) or ADH with invasive carcinoma (2, 8%). Residual ADH or cancer was found in 14 of 24 patients (58%). Of 15 patients with pure ADH, 6 (40%) had residual pathology: ADH (2), DCIS (2) and invasive carcinoma (2). In this group, 27% of patients were reassessed as having DCIS or invasive carcinoma. Of the 9 patients with cancer, 8 (89%) had residual disease in the form of ADH (4) or DCIS (4). Conclusions: ADH found at the margin of a lumpectomy specimen is associated with a high rate of residual ADH and cancer. Over one quarter of the patients with an initial diagnosis of ADH were reassessed as having DCIS or invasive carcinoma. Re-excision in all patients with ADH involving the margin is recommended.