Racial differences in the familial aggregation of breast cancer and other female cancers

Breast Cancer Res Treat. 2005 Feb;89(3):227-35. doi: 10.1007/s10549-004-2046-9.


Although breast cancer familial aggregation has been studied in Caucasians, information for African-Americans is scant. We used family cancer history from the Women's Contraceptive and Reproductive Experiences study to assess the aggregation of breast and gynecological cancers in African-American and Caucasian families. Information was available on 41,825 first and second-degree relatives of Caucasian and 28,956 relatives of African-American participants. We used a cohort approach in which the relative's cancer status was the outcome in unconditional logistic regression and adjusted for correlated data using generalized estimating equations. Race-specific models included a family history indicator, the relative's age, and type. Relative risk (RR) estimates for breast cancer were highest for first-degree relatives, and the overall RR for breast cancer among case relatives was 1.96 (95% CI = 1.68-2.30) for Caucasian and 1.78 (95% CI = 1.41-2.25) for African-Americans. The effect of CARE participants' reference age on their relatives' breast cancer risk was greatest among first-degree relatives of African-American patients with RRs (95% CI) for ages <45 and > or =45 of 2.97 (1.86-4.74) and 1.48 (1.14-1.92), respectively. Among Caucasians, first-degree relatives of case subjects were at greater risk for ovarian cancer, particularly relatives younger than 45 years (RR (95% CI) = 2.06 (1.02-4.12)), whereas African-American first-degree relatives of case subjects were at increased cervical cancer risk (RR (95% CI) = 2.17 (1.22-3.85). In conclusion, these racially distinct aggregation patterns may reflect different modes of inheritance and/or environmental factors that impact cancer risk.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • African Continental Ancestry Group*
  • Breast Neoplasms / ethnology*
  • Breast Neoplasms / pathology
  • Breast Neoplasms / therapy
  • Case-Control Studies
  • Disease-Free Survival
  • European Continental Ancestry Group*
  • Family
  • Female
  • Humans
  • Middle Aged
  • Odds Ratio
  • Ovarian Neoplasms / ethnology*
  • Ovarian Neoplasms / pathology
  • Ovarian Neoplasms / therapy
  • Uterine Neoplasms / ethnology*
  • Uterine Neoplasms / pathology
  • Uterine Neoplasms / therapy