title: Ki-67 expression in sclerosing adenosis and adjacent normal breast terminal ductal lobular units: a nested case-control study from the Mayo Benign Breast Disease Cohort.
abstract: Sclerosing adenosis (SA) increases risk for invasive breast cancer (BC) 2.1 times relative to that in the general population. Here, we sought to evaluate whether the proliferation marker Ki-67 stratifies risk among women with SA. A nested case-control sample of patients with SA was obtained from the Mayo Clinic Benign Breast Disease Cohort. Ki-67 expression was evaluated in SA lesions and in the adjacent normal terminal duct lobular units (TDLU) in women who did (cases, n = 133) or did not (controls, n = 239) develop BC. Ki-67 was scored by intensity and number of positively stained cells per one high-power field (magnification, ×40) (40× HPF) for both SA and normal TDLU. Associations of Ki-67 expression with case-control status were assessed using conditional logistic regression. Higher Ki-67 expression was significantly associated with case-control status in both SA (P = 0.03) and normal background TDLU (P = 0.006). For the SA lesion, >2 average positively stained cells/40× HPF showed an adjusted odds ratio (OR) of 1.9 (95 % CI, 1.1-3.4) compared to samples with an average of ≤2 positively stained cells. For background TDLU, lobules with >2 but ≤6 average positively stained cells showed an adjusted OR of 1.3-1.5, whereas those with an average of >6 positively stained cells had an OR of 2.4 (95 % CI, 1.1-5.3) compared to those with an average of <2 positively stained cells. Among women with SA, increased Ki-67 expression in either the SA lesion or the normal background TDLU carried an approximately twofold increased odds of subsequent BC as compared to lower Ki-67 expression.
authors: Department of Laboratory Medicine and Pathology, Mayo Clinic, 4500 San Pablo Rd, Jacksonville, FL, 32224, USA, nassar.aziza@mayo.edu.
authors: Aziza
authors: A
authors: Nassar
authors: Tanya L
authors: TL
authors: Hoskin
authors: Melody L
authors: ML
authors: Stallings-Mann
authors: Amy C
authors: AC
authors: Degnim
authors: Derek C
authors: DC
authors: Radisky
authors: Marlene H
authors: MH
authors: Frost
authors: Robert A
authors: RA
authors: Vierkant
authors: Lynn C
authors: LC
authors: Hartmann
authors: Daniel W
authors: DW
authors: Visscher
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000150:complications / Q000235:genetics* / Q000473:pathology; D005260:Female; D005348:Fibrocystic Breast Disease / Q000150:complications / Q000235:genetics* / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D019394:Ki-67 Antigen / Q000096:biosynthesis* / Q000235:genetics; D042361:Mammary Glands, Human / Q000378:metabolism* / Q000473:pathology; D008875:Middle Aged; D012307:Risk Factors
chemical_list: D019394:Ki-67 Antigen