Breast Cancer in Latinas: Gene Expression, Differential Response to Treatments, and Differential Toxicities in Latinas Compared with Other Population Groups

Abstract

Disparities in clinical outcomes of breast cancer have been described among different racial and ethnic groups in the U.S. Convincing data exist showing that Latina women have a lower incidence of breast cancer but a higher breast cancer-related mortality rate compared with white women. Noticeable differences in breast cancer incidence are present even within different Latina subsets with a higher incidence in secondand third-generation women compared with foreign born. An increasing amount of data exists pointing to significant differences in the genetics and biology of breast cancer in Latinas as a significant contributor to the higher mortality, including a higher incidence of triple-negative breast cancers (which do not overexpress HER-2 protein and are negative for estrogen receptors and progesterone receptors). Other social and environmental factors are likely to play a significant role as well, including a lower rate of screening mammography, variable access to medical care, among others. Recent data are inconclusive regarding differences among racial/ethnic groups in the response to chemotherapy. Data on racial/ethnic variations in the pharmacogenomics of chemotherapy, endocrine treatments, and toxicity are more limited, with some data suggesting differences in frequencies of polymorphisms of genes involved in the metabolism of some of these agents. Further studies are needed on this subject. The Oncologist 2010;15: 466 -475

Family History and Breast Cancer Hormone Receptor Status in a Spanish Cohort

“…It is possible that genetic susceptibility to breast cancer may differ among ethnic populations. Major differences in gene expression between Hispanics and NHW have also been described [27]. Baumbach et al [28] presented genetic microarray analysis of 28 paraffin-embedded, triple-negative breast cancer samples from Hispanic, white, and black women.…”

Elevated PCNA+ tumor-associated macrophages in breast cancer are associated with early recurrence and non-Caucasian ethnicity

“…Despite improvements in screening and treatment, African American and Hispanic women bear a disproportionate burden of aggressive breast cancer with poor outcomes [2][3][4]. Traditionally, such outcomes disparities have been attributed to lower socioeconomic status (SES) and an associated decrease in access to care.…”

“…Latina patients also have an elevated incidence of triple negative disease, with biological differences in tumors contributing to poor outcomes [4]. A family history of breast cancer confers a higher risk of developing estrogen receptor (ER) negative disease in Hispanic women compared to Caucasian women, suggesting a possible difference in breast cancer subtypes [16].…”

Outcomes of Hispanic women with lymph-node positive, HER2 positive breast cancer treated with neoadjuvant chemotherapy and trastuzumab in Mexico

“…Recent data from Mexico mirror these figures, and breast cancer is, since 2006, the leading cause of cancer mortality in Mexican women, accounting for 14% of cancerrelated deaths [3]. Hispanic women have a lower incidence of breast cancer but a higher breast cancer-related mortality rate compared with white women [4]. There is some evidence that points towards the fact that this is particularly true for women with hormone receptor (HR) negative breast cancer subtypes, both triple negative and HRÀ/HER2þ [5].…”