Breast Cancer Risk Estimates for Relatives of White and African American Women With Breast Cancer in the Women's Contraceptive and Reproductive Experiences Study

Evaluation of the Families SHARE workbook: an educational tool outlining disease risk and healthy guidelines to reduce risk of heart disease, diabetes, breast cancer and colorectal cancer

BACKGROUND

Common diseases such as heart disease, diabetes, and cancer are etiologically complex with multiple risk factors (e.g., environment, genetic, lifestyle). These risk factors tend to cluster in families, making families an important social context for intervention and lifestyle-focused disease prevention. The Families Sharing Health Assessment and Risk Evaluation (SHARE) workbook was designed as an educational tool outlining family health history based risk of heart disease, type 2 diabetes, breast cancer, and colorectal cancer. The current paper describes the steps taken to develop and evaluate the workbook employing a user-centered design approach.

METHODS

The workbook was developed in four steps, culminating in an evaluation focusing on understanding and usability of the tool. The evaluation was based on two Phases of data collected from a sample of mothers of young children in the Washington, D.C., area. A baseline assessment and follow-up approximately two weeks after receipt of the workbook were conducted, as well as focus groups with participants. The design of the workbook was refined in response to participant feedback from the first evaluation Phase and subsequently re-evaluated with a new sample.

RESULTS

After incorporating user-based feedback and revising the workbook, Phase 2 evaluation results indicated that understanding of the workbook components improved for all sections (from 6.26 to 6.81 on a 7-point scale). In addition, 100% of users were able to use the algorithm to assess their disease risk and over 60% used the algorithm to assess family members' disease risk. At follow-up, confidence to increase fruit, vegetable and fiber intake improved significantly, as well.

CONCLUSIONS

The Families SHARE workbook was developed and evaluated resulting in a family health history tool that is both understandable and usable by key stakeholders. This educational tool will be used in intervention studies assessing the effectiveness of family genomics health educators who use the Families SHARE workbook to disseminate family risk information and encourage risk reducing behaviors.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT01498276 . Registered 21 December 2011.

Familial clustering of breast and prostate cancer and risk of postmenopausal breast cancer in the Women's Health Initiative Study

BACKGROUND

Evidence suggests that the risk of breast and prostate cancer is increased among those with a family history of the same disease and particularly among first-degree relatives. However, less is known about the relationship between breast and prostate cancer within families and particularly among minority populations.

METHODS

Analyses of participants in the Women's Health Initiative observational cohort who were free of breast cancer at the time of their baseline examination were conducted. Subjects were followed for breast cancer through August 31, 2009. A Cox proportional hazards regression modeling approach was used to estimate the risk of breast cancer associated with a family history of prostate cancer, breast cancer, and both among first-degree relatives.

RESULTS

There were 78,171 eligible participants, and 3506 breast cancer cases were diagnosed during the study period. A family history of prostate cancer was associated with a modest increase in breast cancer risk after adjustments for confounders (adjusted hazard ratio [aHR], 1.14; 95% confidence interval [CI], 1.02-1.26). In a separate analysis examining the joint impact of both cancers, a family history of both breast and prostate cancer was associated with a 78% increase in breast cancer risk (aHR, 1.78; 95% CI, 1.45-2.19). Risk estimates associated with a family history of both breast and prostate cancer were higher among African American women (aHR, 2.34; 95% CI, 1.09-5.02) versus white women (aHR, 1.66; 95% CI, 1.33-2.08).

CONCLUSIONS

These findings suggest that prostate cancer diagnosed among first-degree family members increases a woman's risk of developing breast cancer. Future studies are needed to determine the relative contributions of genes and a shared environment to the risk for both cancers.

BRCA genetic counseling among at-risk Latinas in New York City: new beliefs shape new generation

Despite the life-saving information that genetic counseling can provide for women at hereditary breast and/or ovarian cancer (HBOC) risk, Latinas disproportionately underuse such services. Understanding Latinas' beliefs and attitudes about BRCA genetic counseling may be the key to better health promotion within this underserved, at-risk group. We conducted 12 focus groups (N = 54) with at-risk Latina women in New York City, followed by 30 in-depth interviews among a subset of the focus group women. Both were professionally transcribed, translated where applicable and data analysis was completed by two coders trained in qualitative methods. Results revealed personal and community knowledge about BRCA genetic counseling was relatively low, although women felt largely positive about counseling. The main motivator to undergo genetic counseling was concerns about learning family members' cancer status, while the main barrier was competing demands. Generational differences were apparent, with younger women (approximately <55 years) reporting that they were more interested in educating themselves about counseling and other ways to prevent cancer. Younger women were also less likely to ascribe to traditionally Latino-centered cultural beliefs which could serve as barriers (e.g. machismo, fatalismo, destino) to undergoing genetic counseling. Participants were largely enthusiastic about educational efforts to increase awareness of genetic counseling among Latinos. Revealing the beliefs and attitudes of underserved Latinas may help shape culturally appropriate educational materials and promotion programs to increase BRCA genetic counseling uptake within this underrepresented community.

African American women's limited knowledge and experiences with genetic counseling for hereditary breast cancer

Genetic counseling and testing for hereditary breast cancer have the potential benefit of early detection and early interventions in African American women. However, African American women have low use of these services compared to White women. We conducted two focus groups with African American women diagnosed with breast cancer (affected group, n = 13) and women with at least one first-degree relative with breast/ovarian cancer (unaffected group, n = 8). A content analysis approach was employed to analyze interview data. Breast cancer survivors had more knowledge about genetic counseling and testing than participants who were unaffected with cancer. However, knowledge about genetic counseling was limited in both groups. Barriers to pursuing genetic counseling and testing included poor understanding of the genetic counseling and testing process, fear of carrying the mutation, concerns about discrimination, and cost. Motivators to participate in genetic counseling and testing included desire to help family members, insurance coverage, and potential of benefiting the larger African American community. Education efforts are needed to increase genetic counseling and testing awareness in the African American community.

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.

Estrogen-related genes and their contribution to racial differences in breast cancer risk

Racial differences in breast cancer risk, including the risks of hormone receptor subtypes of breast cancer, have been previously reported. We evaluated whether variation in genes related to estrogen metabolism (COMT, CYP1A1, CYP1B1, CYP17A1, CYP19A1, ESR1, GSTM1, GSTP1, GSTT1, HSD17B1, SULT1A1, and UGT1A1) contributes to breast cancer risk and/or racial differences in risk within the CARE study, a multi-centered, population-based case-control study of breast cancer. Genetic variation was assessed as single nucleotide polymorphisms (SNPs), haplotypes, and SNP-hormone therapy (HT) interactions within a subset of 1,644 cases and 1,451 controls, including 949 Black women (493 cases and 456 controls), sampled from the CARE study population. No appreciable associations with breast cancer risk were detected for single SNPs or haplotypes in women overall. We detected SNP-HT interactions in women overall within CYP1B1 (rs1800440; p (het) = 0.003) and within CYP17A1 (rs743572; p (het) = 0.009) in which never users of HT were at a decreased risk of breast cancer, while ever users were at a non-significant increased risk. When investigated among racial groups, we detected evidence of an SNP-HT interaction with CYP1B1 in White women (p value = 0.02) and with CYP17A1 in Black women (p value = 0.04). This analysis suggests that HT use may modify the effect of variation in estrogen-related genes on breast cancer risk, which may affect Black and White women to a different extent.

Ethnic, racial and cultural identity and perceived benefits and barriers related to genetic testing for breast cancer among at-risk women of African descent in New York City

BACKGROUND

Due to disparities in the use of genetic services, there has been growing interest in examining beliefs and attitudes related to genetic testing for breast and/or ovarian cancer risk among women of African descent. However, to date, few studies have addressed critical cultural variations among this minority group and their influence on such beliefs and attitudes.

METHODS

We assessed ethnic, racial and cultural identity and examined their relationships with perceived benefits and barriers related to genetic testing for cancer risk in a sample of 160 women of African descent (49% self-identified African American, 39% Black-West Indian/Caribbean, 12% Black-Other) who met genetic risk criteria and were participating in a larger longitudinal study including the opportunity for free genetic counseling and testing in New York City. All participants completed the following previously validated measures: (a) the multi-group ethnic identity measure (including ethnic search and affirmation subscales) and other-group orientation for ethnic identity, (b) centrality to assess racial identity, and (c) Africentrism to measure cultural identity. Perceived benefits and barriers related to genetic testing included: (1) pros/advantages (including family-related pros), (2) cons/disadvantages (including family-related cons, stigma and confidentiality concerns), and (3) concerns about abuses of genetic testing.

RESULTS

In multivariate analyses, several ethnic identity elements showed significant, largely positive relationships to perceived benefits about genetic testing for breast and/or ovarian cancer risk, the exception being ethnic search, which was positively associated with cons/disadvantages, in general, and family-related cons/disadvantages. Racial identity (centrality) showed a significant association with confidentiality concerns. Cultural identity (Africentrism) was not related to perceived benefits and/or barriers.

CONCLUSIONS

Ethnic and racial identity may influence perceived benefits and barriers related to genetic testing for breast and/or ovarian cancer risk among at-risk women of African descent. Genetic counseling services may want to take into account these factors in the creation of culturally-appropriate services which best meet the needs of this heterogenous population.

Use of four biomarkers to evaluate the risk of breast cancer subtypes in the women's contraceptive and reproductive experiences study

Epidemiologic studies suggest that some hormone-related risk factors in breast cancer differentially influence risk for disease subtypes classified by the status of the estrogen and progesterone receptors (ER/PR). However, it remains unclear whether human epidermal growth factor receptor 2 (HER2) or p53 expression status further differentiates these exposure-risk group associations. We evaluated the associations of oral contraceptive (OC) use and reproductive factors with incident invasive breast cancer subtypes among 1,197 population-based cases and 2,015 controls from the Los Angeles County or Detroit components of the Women's Contraceptive and Reproductive Experiences Study. Case-control comparisons by ER/PR/HER2/p53 status were conducted by multivariable polychotomous unconditional logistic regression methods. We found that OC use was not associated with any breast cancer subtype as defined by ER/PR/HER2/p53 status, except for a 2.9-fold increased risk of so-called triple-negative tumors (ER(-)/PR(-)/HER2(-)) among women of 45 to 64 years of age who started OC use before age 18. Parity was associated with a decreased risk of luminal A (ER(+) or PR(+), HER2(-)), luminal B (ER(+) or PR(+)/HER2(+)), and ER(-)/PR(-)/HER2(+) tumors. Age at first full-term pregnancy was positively associated with luminal A tumors among older women. Neither of these reproductive factors was associated with triple-negative tumors. Long duration of breast-feeding lowered the risk of triple-negative and luminal A tumors. p53 status did not define further differential risk patterns. Our findings offer evidence of differences in the hormone-related risk factors between triple-negative cancers and other ER/PR/HER2-defined subtypes of breast cancer.

Family history of cancer and risk of breast cancer in the Black Women's Health Study

INTRODUCTION

Relatively little research has been conducted on familial breast cancer in African American women.

METHODS

Data from the Black Women's Health Study, a prospective cohort study of African American women, were used to assess breast cancer risk in relation to family history of cancer. Since 1995, participants have completed biennial postal questionnaires on health status, risk factors, and family history of cancer. Cox proportional hazards analyses were used to calculate incidence rate ratios (IRRs) and 95% confidence intervals (CI) for family history of breast and other types of cancer.

RESULTS

Among 57,364 participants who were cancer-free at baseline, 1,306 incident breast cancer cases occurred during 12 years of follow-up. The IRR for a first-degree family history of breast cancer relative to no family history was 1.78 (95% CI 1.55-2.06). IRRs varied by the age at diagnosis, from 1.60 (>or=age 55) to 2.76 (<age 35). Results were consistent across subtypes of breast tumor defined by estrogen and progesterone receptor status. Breast cancer risk was also associated with family history of colon cancer (IRR 1.35, 95% CI 1.12-1.63) and possibly with family history of leukemia (IRR 1.42, 95% CI 0.82-2.46).

CONCLUSIONS

These findings indicate a strong familial relationship for breast cancer in African American women. The associations with family history of colon cancer and leukemia warrant further investigation.

Hereditary breast and ovarian cancer syndrome : the impact of race on uptake of genetic counseling and testing

Breast cancer is a significant cause of morbidity and mortality in the United States. Although breast cancer is more common among White American (WA) women, incidence rates are higher among young African American (AA) women. Approximately 5-10% of all breast cancer can be accounted for by germline mutations in the breast cancer (BRCA)1 and BRCA2 genes responsible for hereditary breast and ovarian cancer (HBOC) syndrome. Although genetic counseling (GC) and genetic testing (GT) for HBOC have become widely accepted by the WA population, cancer genetic services are underused among AA. Many investigators have evaluated a wide spectrum of BRCA1 and BRCA2 mutations in the AA and African population with the possible identification of African founder mutations. Barriers to GC and GT include lack of knowledge and/or negative attitudes regarding genetics and genetics research, and concerns regarding the potential for racial discrimination. It is important for future research to focus on ways in which to eliminate barriers to GC and GT to alleviate disparity in the use of genetic services among high-risk AA women.

Incorporating ethnicity into genetic risk assessment for Alzheimer disease: the REVEAL study experience

PURPOSE

To describe how investigators in a multisite randomized clinical trial addressed scientific and ethical issues involved in creating risk models based on genetic testing for African American participants.

METHODS

The following informed our decision whether to stratify risk assessment by ethnicity: evaluation of epidemiological data, appraisal of benefits and risks of incorporating ethnicity into calculations, and feasibility of creating ethnicity-specific risk curves. Once the decision was made, risk curves were created based on data from a large, diverse study of first-degree relatives of patients with Alzheimer disease.

RESULTS

Review of epidemiological data suggested notable differences in risk between African Americans and whites and that Apolipoprotein E genotype predicts risk in both groups. Discussions about the benefits and risks of stratified risk assessments reached consensus that estimates based on data from whites should not preclude enrolling African Americans, but population-specific risk curves should be created if feasible. Risk models specific to ethnicity, gender, and Apolipoprotein E genotype were subsequently developed for the randomized clinical trial that oversampled African Americans.

CONCLUSION

The Risk Evaluation and Education for Alzheimer Disease study provides an instructive example of a process to develop risk assessment protocols that are sensitive to the implications of genetic testing for multiple ethnic groups with differing levels of risk.

Risk assessment models to estimate cancer probabilities

Cancer risk has become a significant research topic due to an increase in statistical risk models built to predict cancer incidence or mortality. Over the past 3 years, 15 models on the development of different types of cancer, including breast, colorectal, prostate, gastric, lung, ovarian, pancreatic, testicular, and skin, have been published. Risk assessment models are dynamic; they need to be updated as often as risks are discovered or changed. Not only are cancer risk models challenging to build, but, due to literacy-related issues, the cancer risk itself is challenging to communicate to the public. Clearly, guidelines outlining how to create valid and reliable risk assessment models are needed.

Diagnostic accuracy of the Gail model in the Black Women's Health Study

The Gail model is used to predict the risk of breast cancer in women of diverse race/ethnic groups for clinical trial protocols. However, this model has only been validated in US white women. Using a nested case-control study design, we evaluated the diagnostic accuracy of the original Gail model (GM) and that of the revised Gail model algorithm for blacks/African-Americans (GM-B) in the Black Women's Health Study (BWHS). Risk profiles were derived via a self reported questionnaire at the time of enrollment into the BWHS in 1995. Biennial questionnaires were obtained from the participants to determine the incident cases of breast cancer. The study of 725 breast cancer cases and 725 controls revealed that the 5-year risk of breast cancer based on the GM ranged from 0.2% to 15.4% among cases and 0.2% to 13.6% among the controls. Based on the GM-B, the 5-year risk of breast cancer ranged from 0.2% to 8.7% among cases and 0.2% to 7.2% among the controls. The sensitivities of the GM and GM-B model with the standard cutoff of 1.7% were 17.9% (95% CI: 15.9-19.9%) and 4.1% (95% CI: 3.0-5.2), respectively. Both the original and the modified version of the Gail model underestimate the risk of developing breast cancer in African-American women. More importantly, the modified Gail Model (GM-B) does a worse job at predicting the development of breast cancer for blacks than the original model (GM).