Lobular neoplasia on core needle biopsy does not require excision

BACKGROUND. Lobular neoplasia (LN), encompassing atypical lobular hyperplasia (ALH) and lobular carcinoma in situ (LCIS), is often an incidental finding on core needle biopsies (CNBs) performed in instances of radiologic densities and/or calcifications. Because LN is generally considered a risk factor for breast carcinoma, the utility of subsequent excision is controversial. METHODS. The authors' database yielded 98 cases of LCIS and/or ALH. Cases containing LN accompanied by a second lesion mandating excision (eg, radial scar, atypical ductal hyperplasia (ADH) and those failing to meet strict diagnostic criteria for LN (eg, atypical cells, mitoses, single-cell necrosis) were excluded. Radiographic calcifications were correlated with their histologic counterparts in tenus of size, number, and pattern. RESULTS. Ninety-one biopsies were performed for calcifications and 7 were performed for mass lesions. The ages of the patients ranged from 35 to 82 years. Fifty-three patients were followed radiologically without excision, 42 of whom had available clinicoradiologic information. The 45 patients who underwent excision were without disease at follow-up periods ranging from 1 to 8 years. Of these 45 patients, 42 (93%) had biopsy results demonstrating only LN. The remaining 3 patients had biopsies with the following findings: ADH in 1 biopsy, residual LCIS and a separate minute focus of infiltrating lobular carcinoma (clearly an incidental finding) in the second biopsy, and ductal carcinoma in situ admixed with LCIS in the third biopsy (a retrospective examination performed by 2 blinded breast pathologists revealed foci of atypical cells and mitoses). CONCLUSIONS. Excision of LN is unnecessary provided that: 1) careful radiographic-pathologic correlation is performed; and 2) strict histologic criteria are adhered to when making the diagnosis. Close radiologic and clinical follow-up is adequate.