Breast Cancer Research and Treatment

, Volume 109, Issue 1, pp 123–139 | Cite as

Epidemiology of basal-like breast cancer

  • Robert C. MillikanEmail author
  • Beth Newman
  • Chiu-Kit Tse
  • Patricia G. Moorman
  • Kathleen Conway
  • Lisa V. Smith
  • Miriam H. Labbok
  • Joseph Geradts
  • Jeannette T. Bensen
  • Susan Jackson
  • Sarah Nyante
  • Chad Livasy
  • Lisa Carey
  • H. Shelton Earp
  • Charles M. Perou


Risk factors for the newly identified “intrinsic” breast cancer subtypes (luminal A, luminal B, basal-like and human epidermal growth factor receptor 2-positive/estrogen receptor-negative) were determined in the Carolina Breast Cancer Study, a population-based, case–control study of African-American and white women. Immunohistochemical markers were used to subtype 1,424 cases of invasive and in situ breast cancer, and case subtypes were compared to 2,022 controls. Luminal A, the most common subtype, exhibited risk factors typically reported for breast cancer in previous studies, including inverse associations for increased parity and younger age at first full-term pregnancy. Basal-like cases exhibited several associations that were opposite to those observed for luminal A, including increased risk for parity and younger age at first term full-term pregnancy. Longer duration breastfeeding, increasing number of children breastfed, and increasing number of months breastfeeding per child were each associated with reduced risk of basal-like breast cancer, but not luminal A. Women with multiple live births who did not breastfeed and women who used medications to suppress lactation were at increased risk of basal-like, but not luminal A, breast cancer. Elevated waist-hip ratio was associated with increased risk of luminal A in postmenopausal women, and increased risk of basal-like breast cancer in pre- and postmenopausal women. The prevalence of basal-like breast cancer was highest among premenopausal African-American women, who also showed the highest prevalence of basal-like risk factors. Among younger African-American women, we estimate that up to 68% of basal-like breast cancer could be prevented by promoting breastfeeding and reducing abdominal adiposity.


Breast cancer subtypes molecular epidemiology 



The work was funded by the Specialized Program of Research Excellence (SPORE) in Breast Cancer at UNC (NIH/NCI P50-CA58223) and the Lineberger Comprehensive Cancer Center Core Grant (P30-CA16086). CMP was supported by NCI R01-CA101227, the Breast Cancer Research Foundation, and the V Foundation for Cancer Research. The authors acknowledge the technical assistance and support of the Immunohistochemistry Core Facility at UNC directed by Dr. Lynn G. Dressler and David Cowan. The authors wish to thank participants in the National Breast Cancer Coalition Advocacy Conference, April 2007, for comments on the results of this study. The authors also thank Drs. Christine Friedenreich and Giske Ursin for helpful discussions.


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Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • Robert C. Millikan
    • 1
    • 2
    Email author
  • Beth Newman
    • 3
  • Chiu-Kit Tse
    • 1
  • Patricia G. Moorman
    • 4
  • Kathleen Conway
    • 1
    • 2
  • Lisa V. Smith
    • 5
    • 6
  • Miriam H. Labbok
    • 7
  • Joseph Geradts
    • 8
  • Jeannette T. Bensen
    • 1
    • 2
  • Susan Jackson
    • 1
    • 2
  • Sarah Nyante
    • 1
  • Chad Livasy
    • 9
  • Lisa Carey
    • 10
  • H. Shelton Earp
    • 2
  • Charles M. Perou
    • 2
    • 11
  1. 1.Department of Epidemiology, CB #7435, School of Public HealthUniversity of North CarolinaChapel HillUSA
  2. 2.Lineberger Comprehensive Cancer Center, School of MedicineUniversity of North CarolinaChapel HillUSA
  3. 3.School of Public HealthQueensland University of TechnologyKelvin GroveAustralia
  4. 4.Department of Community and Family Medicine, School of MedicineDuke UniversityDurhamUSA
  5. 5.Division of Chronic Disease and Injury Prevention, Department of Public HealthLos Angeles CountyLos AngelesUSA
  6. 6.Department of Epidemiology, School of Public HealthUniversity of CaliforniaLos AngelesUSA
  7. 7.Center for Infant and Young Child Feeding and Care, Department of Maternal and Child Health, School of Public HealthUniversity of North CarolinaChapel HillUSA
  8. 8.Department of Pathology, School of MedicineDuke UniversityDurhamUSA
  9. 9.Department of Pathology and Lab MedicineUniversity of North CarolinaChapel HillUSA
  10. 10.Department of Oncology, School of MedicineUniversity of North CarolinaChapel HillUSA
  11. 11.Department of GeneticsUniversity of North CarolinaChapel HillUSA

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