Article

The epidemiology of triple-negative breast cancer, including race.

Division of Cancer Prevention and Control, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA.
Cancer Causes and Control (impact factor: 2.88). 05/2009; 20(7):1071-82. DOI:10.1007/s10552-009-9331-1 pp.1071-82
Source: PubMed

ABSTRACT Predictors of intrinsic breast cancer subtypes, including the triple-negative (TN) subtype, are largely unknown. We evaluated whether anthropometrics, demographics, and reproductive history were associated with distinct breast cancer subtypes.
Invasive breast tumors from a population-based case-control study of 476 (116 black and 360 white) Atlanta women aged 20-54, diagnosed between 1990 and 1992, were centrally reviewed and immunohistochemically analyzed for estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2); then grouped [TN (ER-PR-HER2-); ER-PR-HER2+; ER/PR+HER2+; ER/PR+HER2- (case-only reference group)]. Data were from interviews and anthropometric measurements; adjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated using logistic regression, including both case-only and case-control comparisons.
From the case-only analyses and compared with the ER/PR+HER2- subtype, women with TN tumors were more likely to be obese than normal/underweight [OR = 1.89 (95% CI = 1.22, 2.92)]. Regardless of HER2 status, ER-PR- tumors were associated with black race, young age at first birth, having a recent birth, and being overweight.
Distinct breast cancer subtypes have unique sociodemographic, anthropometric and reproductive characteristics and possibly different pathways for development.

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    Article: Breast feeding, parity and breast cancer subtypes in a Spanish cohort.
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    Article: Parity and lactation in relation to estrogen receptor negative breast cancer in African American women.
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Keywords

95% confidence intervals
 
anthropometric measurements
 
black race
 
case-only analyses
 
case-only reference group)]
 
distinct breast cancer subtypes
 
ER-PR- tumors
 
ER-PR-HER2+
 
ER-PR-HER2-
 
ER/PR+HER2- subtype
 
HER2 status
 
immunohistochemically analyzed
 
intrinsic breast cancer subtypes
 
Invasive breast tumors
 
logistic regression
 
population-based case-control study
 
Predictors
 
recent birth
 
reproductive characteristics
 
reproductive history
 

Katrina Trivers