The high prevalence of TNTs among younger women and particularly younger AA women, along with unique protein expression patterns and poorer survival, suggests varying gene-environment etiologies with respect to age and race/ethnicity and a need for effective therapies.

Objective 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. Methods 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. Results 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. Conclusions Distinct breast cancer subtypes have unique sociodemographic, anthropometric and reproductive characteristics and possibly different pathways for development.

BACKGROUND Few studies have addressed the issue of whether delays in the interval between medical consultation and the diagnosis and treatment of breast carcinoma are greater for African American women than for white women. The authors examined differences with respect to these delays and analyzed the factors that may have contributed to such differences among women ages 20–54 years who had invasive breast carcinoma diagnosed between 1990 and 1992 and who lived in Atlanta, Georgia. METHODS A total of 251 African American women and 580 white women were interviewed and had their medical records reviewed. The authors estimated racial differences in delay times and used polytomous logistic regression to determine the contributions of various factors (socioeconomic and other) to these differences. RESULTS Although most women in both groups were treated within 3 months of initial consultation, 22.4% of African American women and 14.3% of white women had clinical delays of > 3 months. Compared with white women, African American women were more likely to experience delays in diagnosis and treatment. Access to care (as represented by method of detection and insurance status) and poverty index partially accounted for these differences in delay time; however, racial differences in terms of delayed treatment and diagnosis remained even after adjustment for contributing factors. CONCLUSIONS The findings of the current study suggest that among women ages 20–54 years who have breast carcinoma, potentially clinically significant differences in terms of delayed diagnosis and treatment exist between African American women and white women. Improvements in access to care and in socioeconomic circumstances may address these differences to some degree, but additional research is needed to identify other contributing factors. Cancer 2004. Published 2004 American Cancer Society.