title: Dietary intake and breast cancer among carriers and noncarriers of BRCA mutations in the Korean Hereditary Breast Cancer Study.
abstract: BACKGROUND
  Soy intake is associated with a lower risk of breast cancer. However, it is unclear whether the same reduction in risk associated with high soy intake is also applicable to familial or genetic breast cancer.
  
  
  OBJECTIVE
  The aim of this study was to assess the dietary factors among carriers and noncarriers of BRCA mutations in the Korean Hereditary Breast Cancer Study (KOHBRA).
  
  
  METHODS
  The KOHBRA Study is an ongoing project composed of affected breast cancer patients and familial members of breast cancer cases with BRCA mutations. To assess the association between dietary diversity and breast cancer risk, an HR was estimated by comparing affected subjects with their familial nonaffected members. To assess the interaction between the combination of BRCA mutation and diet diversity, the case-only OR (COR) was estimated by comparing BRCA mutation carriers and noncarriers only in affected subjects.
  
  
  RESULTS
  Soy product intake was associated with a lower risk of breast cancer in carriers (HR: 0.39; 95% CI: 0.19, 0.79 for the highest quartile). The highest quartile of meat intake was associated with a higher risk of breast cancer regardless of BRCA mutation in carriers (HR: 1.97; 95% CI: 1.13, 3.44) and noncarriers (95% CI: 1.41; 1.12, 1.78). The associations of meat intake and soybean intake for breast cancer were more prominent in BRCA2 mutation carriers. In the analysis with only cases, the highest quartile of soy intake, but not meat intake, was associated with BRCA-related breast cancer (COR: 0.57; 95% CI: 0.36, 0.91).
  
  
  CONCLUSIONS
  Our study suggests that soy product consumption is associated with lower breast cancer risk and it had an interaction with BRCA mutation.
authors.affiliation: Department of Preventive Medicine, Gachon University of Medicine and Science, Incheon, Korea (K-PK); the Department of Surgery, Breast and Endocrine Service, Seoul National University Bundang Hospital, Gyeonggi-do, Korea (S-WK and EK); the Departments of Preventive Medicine (SHM and SKP) and Biomedical Science (SKP), Seoul National University College of Medicine, Seoul, Korea; the Cancer Research Institute, Seoul National University, Seoul, Korea (SHM and SKP); the Cancer Policy Branch, National Cancer Control Institute, National Cancer Center, Gyeonggi-do, Korea (BP); the Division of Epidemiology and Health Index, Center for Genome Science, Korea Centers for Disease Control & Prevention, Chungcheongbuk-do, Korea (YA); the Department of Surgery, College of Medicine, University of Ulsan and Asan Medical Center, Seoul, Korea (JWL); the Department of Surgery, College of Medicine, Soonchunhyang University, Seoul, Korea (MHL); the Department of Surgery, Hallym University Sacred Heart Hospital, Anyang, Korea (LSK); the Department of Surgery, Ajou University School of Medicine, Suwon, Korea (YJ); the Department of Surgery, Inha University Hospital, Incheon, Korea (YUC); the Department of Surgery, Chonbuk National University Medical School, Jeonju, Korea (BL); and the Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (JHL).
authors.forename: Kwang-Pil
authors.initials: KP
authors.lastname: Ko
authors.forename: Sung-Won
authors.initials: SW
authors.lastname: Kim
authors.forename: Sung Hyun
authors.initials: SH
authors.lastname: Ma
authors.forename: Boyoung
authors.initials: B
authors.lastname: Park
authors.forename: Younjhin
authors.initials: Y
authors.lastname: Ahn
authors.forename: Jong Won
authors.initials: JW
authors.lastname: Lee
authors.forename: Min Hyuk
authors.initials: MH
authors.lastname: Lee
authors.forename: Eunyoung
authors.initials: E
authors.lastname: Kang
authors.forename: Lee Su
authors.initials: LS
authors.lastname: Kim
authors.forename: Yongsik
authors.initials: Y
authors.lastname: Jung
authors.forename: Young Up
authors.initials: YU
authors.lastname: Cho
authors.forename: ByoungKil
authors.initials: B
authors.lastname: Lee
authors.forename: Jennifer H
authors.initials: JH
authors.lastname: Lin
authors.forename: Sue K
authors.initials: SK
authors.lastname: Park
mesh_terms: D000328:Adult; D001943:Breast Neoplasms / Q000453:epidemiology / Q000209:etiology / Q000235:genetics* / Q000517:prevention & control*; D015331:Cohort Studies; D005192:Family Health; D005260:Female; D005638:Fruit; D019398:Genes, BRCA1; D024522:Genes, BRCA2; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D008460:Meat / Q000009:adverse effects*; D008875:Middle Aged; D009154:Mutation; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D017747:Seafood; D045730:Soy Foods; D014675:Vegetables