Abstract B45: A pilot trial of dietary fish and ω-3 fatty acid supplements in women at high risk for breast cancer

Abstract Background: The type of fat consumed in the diet may influence mammary tissue biology and breast cancer risk, with preclinical evidence for inhibitory effects of n-3 versus n-6 polyunsaturated fatty acids (PUFAs) on mammary carcinogenesis. Fish consumption and fish oil supplements are two strategies to increase dietary n-3 fatty acids. Objective: To determine the effects of increased fish consumption on breast adipose tissue fatty acids, we conducted a study of dietary fish versus an n-3 fatty acid supplement in women at increased risk for developing breast cancer. Design: In this three month randomized study, women at high risk for breast cancer received either (a) dietary fish in the form of canned salmon and albacore tuna at a dose of four 6 ounce servings/week or (b) two n-3 fatty acid capsules (1.68 g EPA+DHA)/day for three months. Subjects underwent fasting blood draws monthly and breast adipose tissue samples at baseline and three months for fatty acid profiling by gas chromatography. Results: Both study interventions of dietary fish and n-3 PUFA capsule yielded increased EPA and DHA content in plasma (p<0.0001), erythrocyte membranes (p<0.0001), and breast adipose tissue samples (p <0.01) at 3 months, with also significantly increased total ω-3 PUFAs and decreased n-3/n-6 ratios (p<0.0001). Women taking n-3 PUFA capsules had a greater rise in plasma and erythrocyte membrane EPA relative to those consuming fish (p=0.002), without significant differences in DHA. BMI attenuated the incremental increase in EPA and DHA. Adherence was excellent in both groups at 93.9%, and higher in the dietary fish arm (p=0.01). Conclusions: Dietary fish and n-3 PUFA capsules significantly increase breast adipose tissue EPA and DHA content and represent two well tolerated strategies for future clinical trials of dietary n-3 PUFAs for breast cancer prevention. Citation Format: Shana Straka, Joanne L. Lester, Sarah Puchala, Angela Rose, Rachel Cole, Rebecca R. Andridge, Steven K. Clinton, Martha A. Belury, Lisa D. Yee. A pilot trial of dietary fish and ω-3 fatty acid supplements in women at high risk for breast cancer. [abstract]. In: Proceedings of the Thirteenth Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2014 Sep 27-Oct 1; New Orleans, LA. Philadelphia (PA): AACR; Can Prev Res 2015;8(10 Suppl): Abstract nr B45.