title: Fatty-acid composition in serum phospholipids and risk of breast cancer: an incident case-control study in Sweden.
abstract: The study of the relationship between dietary intake of fatty acids and the risk of breast cancer has not yielded definite conclusions with respect to causality, possibly because of methodological issues inherent to nutritional epidemiology. To evaluate the hypothesis of possible protection of n-3 polyunsaturated fatty acids (PUFA) against breast cancer in women, we examined the fatty-acid composition of phospholipids in pre-diagnostic sera of 196 women who developed breast cancer, and of 388 controls matched for age at recruitment and duration of follow-up, in a prospective cohort study in Umeâ, northern Sweden. Individual fatty acids were measured as a percentage of total fatty acids, using capillary gas chromatography. Conditional logistic-regression models showed no significant association between n-3 PUFA and breast-cancer risk. In contrast, women in the highest quartile of stearic acid had a relative risk of 0.49 (95% confidence interval, 0.22-1.08) compared with women in the lowest quartile (trend p = 0.047), suggesting a protective role of stearic acid in breast-cancer risk. Besides stearic acid, women in the highest quartile of the 18:0/18:1 n-9c ratio had a relative risk of 0.50 (95% confidence interval, 0.23-1.10) compared with women in the lowest quartile (trend p = 0.064), suggesting a decrease in breast-cancer risk in women with low activity of the enzyme delta 9-desaturase (stearoyl CoA desaturase), which may reflect an underlying metabolic profile characterized by insulin resistance and chronic hyper-insulinemia.
authors.affiliation: Laboratoire de Biologie des Tumeurs, E.A. 2103, Unité de Recherche Associée Université-INRA, Faculté de Médecine, Tours, France.
authors.forename: V
authors.initials: V
authors.lastname: Chajès
authors.forename: K
authors.initials: K
authors.lastname: Hultén
authors.forename: A L
authors.initials: AL
authors.lastname: Van Kappel
authors.forename: A
authors.initials: A
authors.lastname: Winkvist
authors.forename: R
authors.initials: R
authors.lastname: Kaaks
authors.forename: G
authors.initials: G
authors.lastname: Hallmans
authors.forename: P
authors.initials: P
authors.lastname: Lenner
authors.forename: E
authors.initials: E
authors.lastname: Riboli
mesh_terms: D001943:Breast Neoplasms / Q000097:blood / Q000737:chemistry* / Q000453:epidemiology; D016022:Case-Control Studies; D005231:Fatty Acids, Unsaturated / Q000032:analysis* / Q000097:blood; D005260:Female; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D019308:Palmitic Acid / Q000032:analysis / Q000097:blood; D010743:Phospholipids / Q000097:blood / Q000737:chemistry*; D011446:Prospective Studies; D012306:Risk; D013229:Stearic Acids / Q000032:analysis / Q000097:blood; D013548:Sweden / Q000453:epidemiology
chemical_list: D005231:Fatty Acids, Unsaturated; D010743:Phospholipids; D013229:Stearic Acids; D019308:Palmitic Acid; C031183:stearic acid