Examination of ancestral informative markers and self-reported race with tumor characteristics of breast cancer among Black and White women.
African American (AA) women have a higher mortality from breast cancer (BC) compared to European American (EA) women. This may be due to the higher proportion of AA women with tumors that are diagnosed at more advanced stages and are characterized as being estrogen receptor negative (ER-)/progesterone receptor negative (PR-). Our study sought to determine whether self-reported race and percent African ancestry were associated with BC tumor characteristics. In a multi-center, population-based case-control study of BC, we determined percent African ancestry using ancestry informative markers (AIM) among women self-reporting race as AA or Black. BC tumor characteristics were associated with self-reported race (including a 30 % reduction in ER+/PR+ tumors [95 % confidence interval [CI]: 0.6-0.9] and a 1.5-fold increased risk of high grade [95 % CI: 1.2-1.9] for AA women compared to EA women). AIMs among AA women were not associated with BC tumor characteristics (AA women with ≥95 % versus <80 % African ancestry, odds ratio [OR] = 1.0 for ER+/PR+ [95 % CI: 0.6-1.8] and OR = 0.9 for high-grade tumors [95 % CI: 0.6-1.4]). Similar findings were observed for BC stage. While BC subtypes were associated with self-reported race, BC subtypes were not associated with percent African ancestry. These study results suggest that subtle differences in percent African ancestry are less important than the overall presence of African ancestry in relation to BC tumor characteristics.
Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave. N., Mail Stop M4-B874, Seattle, WA 98109-1024, USA. kreding@u.washington.edu
Kerryn W
KW
Reding
Christopher S
CS
Carlson
Orsalem
O
Kahsai
Christina C
CC
Chen
Andrew
A
McDavid
David R
DR
Doody
Chu
C
Chen
India
I
Ornelas
Kimberly
K
Lowe
Leslie
L
Bernstein
Linda
L
Weiss
Jill A
JA
McDonald
Michael S
MS
Simon
Brian
B
Strom
Polly A
PA
Marchbanks
Ronald
R
Burkman
Robert
R
Spirtas
Jonathan M
JM
Liff
Kathleen E
KE
Malone
D000328:Adult; D001741:Black or African American / Q000235:genetics*; D001943:Breast Neoplasms / Q000208:ethnology / Q000378:metabolism* / Q000473:pathology; D016022:Case-Control Studies; D005260:Female; D005819:Genetic Markers; D006801:Humans; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D012307:Risk Factors; D057566:Self Report; D044465:White People
D005819:Genetic Markers; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone