Significance of Extent of Lobular Neoplasia on Breast Core Biopsy

Abstract

Objective We reviewed our excisional biopsy findings in cases when core needle biopsy (CB) found lobular neoplasia (LN) as a primary diagnosis. We also correlated the core needle biopsy and excisional biopsy findings according to the quantitative and qualitative extent of lobular neoplasia found on the core needle biopsy specimen. Design We reviewed the mammographic findings and correlated the histopathological findings of core needle biopsy and subsequent surgical excision in cases when the diagnosis on core needle biopsy was lobular neoplasia. On the core needle biopsy the quantity of lobular neoplasia was categorized as involving one to two lobules, three to four lobules, or more than four lobules and qualitatively the lobular neoplasia was characterized as either atypical lobular hyperplasia (ALH) or lobular carcinoma in situ (LCIS). Results In the twelve cases with lobular neoplasia alone on core needle biopsy, excision showed lobular neoplasia in seven cases, atypical ductal hyperplasia (ADH) in three cases, intraductal carcinoma in one case, and in one case infiltrating carcinoma (17% with carcinoma). From the ten cases when the diagnosis was lobular neoplasia and atypical intraductal hyperplasia on core needle biopsy, excision showed lobular neoplasia in four cases, ADH in two cases, intraductal carcinoma in two cases, and in two cases infiltrating carcinoma (40% with carcinoma). The quantitative or qualitative characterization of the lobular neoplasia on core needle biopsy did not prove to be a predictor of outcome in the subsequent excisional biopsies. Conclusions Although these results must be confirmed by larger studies our findings suggest that excisional biopsy should be performed when lobular neoplasia is diagnosed on core needle biopsy regardless of the radiologic findings or extent of lobular neoplasia on core needle biopsy.