[158] Significance of Focal Lobular Neoplasia in Breast Core Needle Biopsy

SM El Jamal, S Klimberg, R Henry-Tillman, S Korourian. University of Arkansas for Medical Sciences, Little Rock, AR

Background: Management of Lobular neoplasia (LN), encompassing atypical lobular hyperplasia (ALH) and lobular carcinoma in situ (LCIS) remains controversial. Many studies suggest surgical excision following a diagnosis of LN on core needle biopsy; others see no need for any intervention. This study is aimed to assess the risk for concurrent invasive carcinoma or ductal carcinoma in situ.
Design: We searched the database of the Pathology Department at a tertiary referral center for breast core biopsies from July 1997 to June 2008. We identified all biopsies diagnosed as LN, LCIS, and ALH. All biopsies with concurrent diagnosis of atypical ductal hyperplasia (ADH), ductal carcinoma in situ (DCIS), pleomorphic variant of LCIS, or invasive carcinomas were excluded from the study. Immunostain for E-cadherin was performed on all cases. Follow-up studies were reviewed. The presence of flat epithelial atypia (FEA) was also evaluated.
Results: 3763 breast biopsies were performed during this period. 176 patients (4.6%) were diagnosed with LN. 127 patients were excluded from this study due to the presence of other malignant or premalignant lesions. 49 cases (1.3%) were diagnosed with LN or LN with a benign lesion. 10 patients were excluded due to lack of follow-up. Of the remaining 39 patients; 4 had prior history of invasive cancer and 9 had a family history of breast or ovarian cancer. Lobular neoplasia was confirmed by E-cadherin on all but 6 core biopsies in which the area of interest was absent on the deeper cut. 25 of these patients had biopsies due to abnormal calcification. 8 patients had associated mass lesions, and 6 patients had other radiographic abnormalities. 7 patients had associated FEA. The follow-up excision of 2 of the 39 patients (5.1%) showed DCIS. One of them had prior history of infiltrating carcinoma, and the other had a family history of breast cancer. A third patient had a 9 mm focus of infiltrating carcinoma on excision. This patient had also prior history of infiltrating lobular carcinoma in the same breast. The mammogram of all three patients showed mass lesion, one of them also showed calcifications. Only one of the three patients had FEA. 24 of 39 patients (61%) in this study had additional foci of LN on excision.
Conclusions: These results suggest the diagnosis of non-pleomorphic variant of LN on core needle biopsy may not mandate excision in all cases. Our study also suggests that FEA associated with LN probably does not carry any significant additional risk, however; more detailed studies on FEA are needed.
Category: Breast

Tuesday, March 10, 2009 9:30 AM

Poster Session III # 34, Tuesday Morning