title: Histopathology of fibroadenoma of the breast.
abstract: The aim of this study was to make a thorough inventory of the histologic features of epithelium and stroma within and adjacent to breast fibroadenomas in 396 cases. Breast fibroadenomas seemed to display a wide spectrum of proliferative and nonproliferative histologic changes. Hyperplasia (excluding mild hyperplasia) within the fibroadenoma was found in 32.3% of cases. Carcinoma in situ (CIS; 5 ductal, 3 lobular) was found in 8 fibroadenomas (2.0%) removed from 6 patients, the youngest of whom was 40 years of age. In 3 cases CIS was not confined to the fibroadenoma, but also involved the adjacent parenchyma. No invasive carcinoma was present within this series. Complex histologic features were seen in 40.4% of cases, mostly in relatively older patients (mean age, 35.4 years). Hyperplasia in adjacent tissue was found in 8.8% of cases, usually in older patients (mean age, 45.5 years). Known risk-elevating lesions in and around breast fibroadenomas occur frequently and mostly in patients older than 35 years. These findings may have consequences for the clinical management of a subgroup of patients with fibroadenoma.
authors.affiliation: Departments of Pathology, Free University Hospital, PO Box 7057, 1007 MB Amsterdam, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: Kuijper
authors.forename: E C
authors.initials: EC
authors.lastname: Mommers
authors.forename: E
authors.initials: E
authors.lastname: van der Wall
authors.forename: P J
authors.initials: PJ
authors.lastname: van Diest
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000473:pathology*; D002278:Carcinoma in Situ / Q000473:pathology; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000473:pathology; D018275:Carcinoma, Lobular / Q000473:pathology; D002648:Child; D005260:Female; D018226:Fibroadenoma / Q000473:pathology*; D006801:Humans; D006965:Hyperplasia / Q000473:pathology; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary / Q000473:pathology