Excisional biopsy should be performed if lobular carcinoma in situ is seen on needle core biopsy

CONTEXT: Percutaneous image-guided core biopsy is increasingly becoming the method of choice to evaluate impalpable breast lesions presenting with mammographically detected calcifications or as a mammographically detected mass. Infrequently, a diagnosis of a primary lobular lesion is rendered by needle core biopsy. Although lobular carcinoma in situ (LCIS) and atypical lobular hyperplasia (ALH) are not themselves detectable by mammography, they can be associated with calcifications. The management of patients with a primary diagnosis of LCIS or ALH on needle core biopsy is uncertain. Recommendations include excisional biopsy, tamoxifen citrate therapy, mammographic surveillance, or a combination of these approaches. OBJECTIVE: The purpose of this study was to report the histologic findings of excisional biopsies performed after ALH or LCIS was found in a needle core biopsy. DESIGN: Hematoxylin-eosin-stained slides of 20 needle core biopsy specimens from patients with a primary diagnosis of LCIS or ALH were retrieved from the consultation and surgical pathology files of New York Presbyterian Hospital-Weill Medical College of Cornell University. Histologic diagnoses were confirmed in all cases. RESULTS: Fourteen cases of primary LCIS and 6 cases of ALH found on needle core biopsy were identified. Subsequent excisional biopsy of the 14 LCIS cases revealed the following: LCIS, ductal carcinoma in situ, invasive carcinoma (1 patient; 7%); LCIS, infiltrating lobular carcinoma (1 patient; 7%); LCIS, ductal carcinoma in situ (1 patient; 7%); LCIS (8 patients; 57%); and ALH with or without atypical ductal hyperplasia (3 patients; 21%). Among the 6 patients with ALH on needle core biopsy, 1 had infiltrating lobular carcinoma and LCIS and 2 had LCIS in subsequent excision; other excisions for ALH were benign. Overall, 3 (21%) of 14 patients with a primary diagnosis of LCIS on needle core biopsy had a more significant lesion (ductal carcinoma in situ or invasive carcinoma) in a subsequent excisional biopsy. CONCLUSIONS: Data obtained in this study and in previously published reports lead us to conclude that excisional biopsy may be indicated and should be considered when LCIS is found on needle core biopsy in order to more fully examine the biopsy site for coexistent, clinically inapparent intraductal or invasive carcinoma that may be present in about 25% of these patients. The small number of ALH cases studied produced inconclusive results. We recommend that excisional biopsy be considered if atypical ductal hyperplasia is present with ALH in a needle core biopsy or if the diagnosis of the biopsy specimen is discordant with the mammographic findings.