Abstract 1878: Dietary vitamin A intake and breast cancer risk among African American women: The AMBER Consortium
Authors: Cheng Ting-Yuan D. , McCann Susan E. , Zirpoli Gary , Yao Song , Bandera Elisa V. , Kolonel Laurence N. , Rosenberg Lynn , Olshan Andrew F. , Palmer Julie R. , Ambrosone Christine B. 
Published: August 2015

Abstract
Introduction: Some studies in women of European descent showed an inverse association of dietary vitamin A intake with breast cancer risk, in particular, among premenopausal women. However, it is unknown whether the associations exist among women of African descent.
Methods: In the African American Breast Cancer Epidemiology and Risk (AMBER) Consortium, we included data from 2487 breast cancer cases and 11,843 controls from the three studies that had food frequency questionnaires (FFQs) (Black Women's Health Study [BWHS], Multiethnic Cohort Study [MEC], and Women's Circle of Health Study [WCHS]). Total vitamin A (preformed vitamin A from animal sources plus carotenoids from fruits and vegetable) intake in μg retinol equivalent (RE) from diet only was assessed by FFQ, and estrogen receptor (ER) status was abstracted from pathology reports. Logistic regression was performed to estimate odds ratios (OR) and 95% confidence intervals (CI) for study-specific quintiles adjusting for age, education, body mass index, study, time period, geographical region, family history of breast cancer, age at menarche, parity, age at first birth, use of hormone replacement therapy, duration of oral contraceptive use, smoking, alcohol use, and total energy intake.
Results: We observed no association of dietary total vitamin A intake with ER-positive breast cancer overall. However, dietary total vitamin A intake was inversely associated with ER-positive breast cancer among premenopausal women (quintiles 5 vs. 1: OR = 0.66, 95% CI = 0.47-0.93; p-trend = 0.022), but not among postmenopausal women (quintiles 5 vs 1: OR 1.06, 95% CI 0.81-1.39; p-trend = 0.89). There was no evidence for an association of dietary total vitamin A intake with ER-negative breast cancer, regardless of menopausal status. Only BWHS and MEC had information on multivitamin supplement use; adjusting for this variable did not change the associations in these two studies.
Conclusion: A higher versus lower consumption of total vitamin A from diet was associated with a lower risk of ER-positive breast cancer among premenopausal African American women. This finding is consistent with the observation in women of European decent; the potentially beneficial influence of vitamin A on ER-positive breast cancer warrants investigation. (Funding: NIH/NCI P01 CA151135)
Citation Format: Ting-Yuan D. Cheng, Susan E. McCann, Gary Zirpoli, Song Yao, Elisa V. Bandera, Laurence N. Kolonel, Lynn Rosenberg, Andrew F. Olshan, Julie R. Palmer, Christine B. Ambrosone. Dietary vitamin A intake and breast cancer risk among African American women: The AMBER Consortium. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1878. doi:10.1158/1538-7445.AM2015-1878