Abstract P4-14-06: Characteristics of benign breast disease and subsequent risk of breast cancer differ by age among African Americans
Authors: Cote Michele L , Ruterbusch Julie J , Bandyopadhyay Sudeshna , Ahmed Quratulain , Alosh Barra , Abdulfatah Eman , Arabi Haitham , Ali-Fehmi Rouba Lynn 
Published: May 2015

Introduction: A history of benign breast disease (BBD) is common and certain established pathologic features are associated with increased breast cancer risk. These associations have been reported primarily from studies of white women, where incidence of BBD peaks in the 4th or 5th decade of life. Previous work in an African American (AA) cohort of women with BBD showed AA women were younger at their first BBD diagnosis. Thus investigating whether different features of benign lesions may be associated with age and/or subsequent breast cancer risk in this population is warranted.

Methods: Benign breast biopsies from 1,867 AA women with BBD diagnosed from 1997-2003 were microscopically reviewed for 15 benign features (apocrine metaplasia (AM), ductal hyperplasia (DH), atypical ductal hyperplasia (ADH), lobular hyperplasia (LH), calcifications (Calc), cysts, duct ectasisa (DE), fibroadenoma (FA), fibrosis, intraductal papilloma (IDP), radial scar (RS), sclerosing adenosis (SA), columnar cell alterations (CC), mucocele-like tumors (MLT), and atropy), and followed for subsequent breast cancer in metropolitan Detroit, Michigan. Data from 439 women under 40 and 1,428 women 40 and older at BBD diagnosis were available for analysis, with a mean follow-up time of 14 years. Differences between age categories for BBD features were compared using chi-square tests, and risk of breast cancer was estimated with odds ratios (OR) and 95% confidence intervals (95% CI) calculated from logistic regression analysis.

Results: Women 40 and over were more likely to be diagnosed with nearly all of the benign characteristics compared to younger women, including: AM, DH, Calc, cysts, CC, and ADH (all p-values &lt;0.001). Younger women were more likely to present with FA (56% to 43%, p-value&lt;0.001) and no atrophy (44% versus 24%, p-value&lt;0.001) compared to older women. Risk of subsequent breast cancer was associated with cysts (OR=3.95, 95% CI: 1.09, 14.29) in the younger age group, but not the older (OR=1.25, 95% CI: 0.76, 2.03). CC were also associated with breast cancer risk in the young (OR=5.35, 95% CI: 1.45, 19.73) but not the older women (OR=1.44, 95% CI: 0.82, 2.50). RS were associated with increased risk in both groups, but only statistically significant for the older women (OR=3.60, 95% CI: 1.54, 8.39), and not the younger women (OR=6.64, (95% CI: 0.73, 60.67). Similarly, risk of cancer was associated with a diagnosis of ADH in both groups, but only statistically significant among older women (OR=3.02, 95% CI: 1.34, 6.79), and not younger women (OR=6.75, 95% CI: 0.71, 64.43).

Conclusions: Characteristics of BBD differ by age, with more women over the age of 40 being diagnosed with various conditions. Risk of subsequent cancer also varies, although RS, CC and ADH appear to increase risk in both age groups.

Citation Format: Michele L Cote, Julie J Ruterbusch, Sudeshna Bandyopadhyay, Quratulain Ahmed, Barra Alosh, Eman Abdulfatah, Haitham Arabi, Rouba Lynn Ali-Fehmi. Characteristics of benign breast disease and subsequent risk of breast cancer differ by age among African Americans [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P4-14-06.