Original Contribution Lobular carcinoma in situ/atypical lobular hyperplasia on breast needle biopsies: does it warrant surgical excisional biopsy? A study of 27 cases Maura O’Neil, MD, Rashna Madan, MD, Ossama W. Tawfik, MD, PhD, Patricia A. Thomas, MD, Fang Fan, MD, PhD ⁎ Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, KS 66160-7417, USA Abstract Lobular neoplasia including lobular carcinoma in situ (LCIS) and atypical lobular hyperplasia (ALH) may be identified in breast core needle biopsies as incidental findings or associated with microcalcifications. There are no general consensus guidelines for follow-up management in patients when lobular neoplasia is the only abnormal finding on core needle biopsy. The aim of this study was to evaluate our experience in the follow-up of these patients. A total of 3163 breast core needle biopsies were retrieved from the surgical pathology files between 2003 and 2009; among them, 56 (1.8%) cases were identified with a diagnosis of ALH or LCIS. Eleven cases were excluded because of the presence of a concurrent more severe lesion in the biopsies that mandated excision. The remaining 45 cases contained only ALH or LCIS and otherwise benign breast tissue; 27 had surgical excision follow-up. In the surgical excision specimens, 5 (19%) of 27 cases showed more severe lesions or were “upgraded” (3 invasive ductal carcinomas, 1 invasive lobular carcinoma, and 1 ductal carcinoma in situ). Histologic features of the lobular neoplasia on the cores, including association with microcalcifications, pagetoid involvement of ducts, and extensive lobular involvement, were retrospectively evaluated. These histologic features were found to have no predictive value for a more severe lesion in the subsequent excision. We suggest that patients with LCIS/ALH on core needle biopsy should be considered for surgical excision to rule out a more significant lesion regardless of the histologic features. © 2010 Elsevier Inc. All rights reserved. Keywords: Lobular carcinoma in situ; Atypical lobular hyperplasia; Core needle biopsy 1. Introduction The term lobular carcinoma in situ (LCIS) was first introduced by Foote and Stewart in 1941 [1] as a rare form of mammary carcinoma. They described it as a noninvasive lesion with characteristic proliferation within lobules and frequently associated with invasive lobular carcinoma (ILC) with similar cytologic features. Atypical lobular hyperplasia (ALH) was later defined as a similar lesion as LCIS but with a lesser extent of acinar involvement. The designation of lobular neoplasia or lobular intraepithelial neoplasia was suggested to encompass ALH and LCIS [2]; however, this term is still not widely accepted in clinical practice as stated in the most recent seventh edition of the AJCC Cancer Staging Handbook [3]. When Foote and Stewart [1] described LCIS, they recommended mastectomy for treatment because they con- sidered LCIS a precursor lesion. Subsequent long-term follow- up studies showed that LCIS and ALH were associated with increased risk of developing invasive breast carcinomas; the risk was approximately equal in both breasts, and the majority of breast cancer that developed was invasive ductal carcinoma (IDC) of no special type [4,5]. Therefore, LCIS and ALH have traditionally been considered to be risk factors rather than precursors for the subsequent development of breast carcino- ma. However, more recent studies have shown that breast carcinoma is 3 times more prevalent in the ipsilateral breast of LCIS compared with the contralateral breast; and coexistent LCIS and ILC often contain similar genetic alterations, suggesting that at least some LCISs represent actual precursors with progression to carcinoma [6,7]. Available online at www.sciencedirect.com Annals of Diagnostic Pathology 14 (2010) 251 – 255 ⁎ Corresponding author. E-mail address: ffan@kumc.edu (F. Fan). 1092-9134/$ – see front matter © 2010 Elsevier Inc. All rights reserved. doi:10.1016/j.anndiagpath.2010.04.002