Abstract B17: Family history of breast and ovarian cancer prevalence and its association with triple-negative subtype in Hispanic women

Background: A family history of breast cancer in a first-degree relative is an established risk factor for breast cancer; however, little is known about the profile of breast and ovarian family history in Hispanic/Latina women. Importance of this relates to recent reports showing a high prevalence of BRCA mutations in Hispanic/Latina women and a pattern of multiple recurrent mutations. In addition, less is known about the association of family history and tumor subtype in this growing ethnic group in the U.S.

Methods: Study participants included breast cancer patients of Mexican descent enrolled in the Ella Binational Breast Cancer Study. We first assessed the self-reported breast and ovarian family history profile in 1,150 women. Second, we compared differences in family history of breast and ovarian cancer prevalence between triple negative breast cancer (TNBC) and non-TNBC in 914 patients with available tumor subtype data. Logistic regression was conducted to compare odds of TNBC to non-TNBC according to family history of breast and ovarian cancer.

Results: Prevalence of breast cancer family history in a first- and first- or second-degree relative was 13.1% and 24.1%, respectively. A history of breast or ovarian cancer in first-degree relatives was reported in 14.9% of the women. After adjustment for age and country of residence, women with a first-degree relative with breast cancer were more likely to be diagnosed with TNBC compared to non-TNBC (OR=1.98; 95% CI, 1.26-3.11). The odds of TNBC compared to non-TNBC was 1.93 (95% CI, 1.26–2.97) for women with first-degree relatives with breast or ovarian cancer. There was a suggestion of stronger associations between family history and TNBC among women diagnosed at age <50 compared to those >50 years for breast cancer history in first-degree (P-interaction=0.14) and first- or second-degree relatives (P-interaction=0.07).

Conclusion: Findings suggest that familial cancers are associated with triple negative subtype, possibly related to the prevalence of BRCA mutations in Hispanic women, which are strongly associated with TNBC. Improvement in collection of family history through new tools and instruments targeting English- and Spanish-speaking Hispanic women should be a priority for future research. Identification of a strong family history can ultimately affect treatment plans, screening practices, and prevention options both for patients and their relatives.

Citation Format: Maria Elena Martinez, Kristin Anderson, Patricia Thompson, Betsy C. Wertheim, Lorena Martin, Ian Komenaka, Melissa Bondy, Adrian Daneri-Navarro, Maria Mercedes Meza-Montenegro, Luis Enrique Gutierrez-Millan, Abenaa Brewster, Lisa Madlensky, Malaika Tobias, Loki Natarajan. Family history of breast and ovarian cancer prevalence and its association with triple-negative subtype in Hispanic women. [abstract]. In: Proceedings of the Seventh AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 9-12, 2014; San Antonio, TX. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2015;24(10 Suppl):Abstract nr B17.

Abstract B09: Acculturation, behavioral factors, and family history of breast cancer among Mexican and Mexican-American women

Introduction: Incidence rates for breast cancer are higher among Mexican-American (MA) women in the US than women living in Mexico. Studies have shown higher prevalence of breast cancer risk factors in higher vs. lower acculturated Hispanic/Latina women in the US. We compared the prevalence for behavioral risk factors and family history of breast cancer by level of acculturation and country of residence in women of Mexican descent.

Methods: Data were collected from 1,201 recently diagnosed breast cancer patients living in Mexico (n=581) and MAs in the US (n=620). MA participants were categorized into three acculturation groups (Spanish dominant, bilingual and English dominant) according to responses to an 8-item language acculturation scale, while women living in Mexico were used as the reference group. Prevalence of behavioral risk factors and family history of breast cancer were compared among the acculturation groups adjusting for age at diagnosis and education level.

Results: In the final adjusted models, bilingual and English-dominant MAs were significantly more likely to have a body mass index > 30 kg/m2, consume more than one alcoholic beverage a week, and report having a family history of breast cancer when compared to women living in Mexico. All three US acculturation groups were significantly more likely to have low total energy expenditure (<533 kcal/day) than women in Mexico. English-dominant women were significantly less likely to smoke cigarettes than the Mexican comparison group.

Conclusions: Our findings on acculturation and distributions of behavioral risk factors and family history of breast cancer add to the growing body of evidence suggesting acculturation has both positive and negative impacts on health behavior in Hispanic/Latino populations living in the US. Interventions and public health policies may benefit from considering these relationships when targeting health programs and campaigns to Mexican-American and Mexican women.

Citation Format: Jesse Nodora, Renee Cooper, Maria Elena Martinez, Gregory Talavera, Patricia Thompson, Ian Komenaka, Melissa Bondy, Abenaa Brewster, Adrian Daneri-Navarro, Maria Mercedes Meza-Montenegro, Luis Enrique Gutierrez-Millan. Acculturation, behavioral factors, and family history of breast cancer among Mexican and Mexican-American women. [abstract]. In: Proceedings of the Seventh AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 9-12, 2014; San Antonio, TX. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2015;24(10 Suppl):Abstract nr B09.

Genome-wide association study identifies multiple susceptibility loci for glioma

Previous genome-wide association studies (GWASs) have shown that common genetic variation contributes to the heritable risk of glioma. To identify new glioma susceptibility loci, we conducted a meta-analysis of four GWAS (totalling 4,147 cases and 7,435 controls), with imputation using 1000 Genomes and UK10K Project data as reference. After genotyping an additional 1,490 cases and 1,723 controls we identify new risk loci for glioblastoma (GBM) at 12q23.33 (rs3851634, near POLR3B, P=3.02 × 10(-9)) and non-GBM at 10q25.2 (rs11196067, near VTI1A, P=4.32 × 10(-8)), 11q23.2 (rs648044, near ZBTB16, P=6.26 × 10(-11)), 12q21.2 (rs12230172, P=7.53 × 10(-11)) and 15q24.2 (rs1801591, near ETFA, P=5.71 × 10(-9)). Our findings provide further insights into the genetic basis of the different glioma subtypes.

Acculturation, Behavioral Factors, and Family History of Breast Cancer among Mexican and Mexican-American Women

BACKGROUND

Incidence rates for breast cancer are higher among Mexican-American (MA) women in the United States than women living in Mexico. Studies have shown higher prevalence of breast cancer risk factors in more acculturated than less acculturated Hispanic/Latinas in the United States. We compared the prevalence of behavioral risk factors and family history of breast cancer by level of acculturation and country of residence in women of Mexican descent.

METHODS

Data were collected from 1,201 newly diagnosed breast cancer patients living in Mexico (n = 581) and MAs in the United States (n = 620). MA participants were categorized into three acculturation groups (Spanish dominant, bilingual, and English dominant); women living in Mexico were used as the referent group. The prevalence of behavioral risk factors and family history of breast cancer were assessed according to acculturation level, adjusting for age at diagnosis and education.

RESULTS

In the adjusted models, bilingual and English-dominant MAs were significantly more likely to have a body mass index of 30 kg/m(2) or greater, consume more than one alcoholic beverage a week, and report having a family history of breast cancer than women living in Mexico. All three U.S. acculturation groups were significantly more likely to have lower total energy expenditure (≤533 kcal/d) than women in Mexico. English-dominant women were significantly less likely to ever smoke cigarettes than the Mexican group.

CONCLUSIONS

Our findings add to the limited scientific literature on the relationships among acculturation, health behavior, and family history of breast cancer in Mexican and MA women.

A cross-sectional analysis of polycyclic aromatic hydrocarbons and diesel particulate matter exposures and hypertension among individuals of Mexican origin

BACKGROUND

Epidemiological studies have found that particulate matter is associated with increases in blood pressure. Yet, less is known about the effects of specific sources or constituents of particulate matter, such as diesel particulate matter or polycyclic aromatic hydrocarbons (PAHs). We evaluated associations between self-reported hypertension and residential air levels of diesel particulate matter and PAHs among individuals of Mexican origin living in a large inner city.

METHODS

The Mano a Mano cohort (established in 2001 by the University of Texas MD Anderson Cancer Center) is comprised of individuals of Mexican origin residing in Houston, Texas. Using geographical information systems, we linked modeled annual estimates of PAHs and diesel particulate matter at the census tract level from the 2002 and 2005 U.S. Environmental Protection Agency's National-Scale Air Toxics Assessment to baseline residential addresses of cohort members who enrolled from 2001 to 2003 or 2004 to 2006, respectively. For each enrollment period, we applied mixed-effects logistic regression models to determine associations between diesel particulate matter and PAHs, separately, and self-reported hypertension while adjusting for confounders and the clustering of observations within census tracts and households.

RESULTS

The study population consisted of 11218 participants of which 77% were women. The mean participant age at baseline was 41 years. Following adjustment for age, there was a dose-dependent, positive association between PAHs and hypertension (medium exposure, adjusted odds ratio (OR) = 1.09, 95% CI: 0.88-1.36; high exposure, OR = 1.40, 95% CI: 1.01-1.94) for individuals enrolled during 2001-2003; associations were generally similar in magnitude, but less precise, following adjustment for age, gender, smoking, and BMI. No association was detected for the later period. There was no evidence of an association between residential levels of diesel particulate matter and hypertension.

CONCLUSIONS

This study builds on a limited number of prior investigations of the association between ambient air levels of PAHs or diesel particulate matter and hypertension by focusing on a relatively young cohort of predominantly adult women of Mexican origin. Future analyses are warranted to explore associations in the cohort using incident hypertension when sufficient data become available and to further examine associations between specific chemical constituents of particulate matter and hypertension in this and other populations.

A pooled multisite analysis of the effects of atopic medical conditions in glioma risk in different ethnic groups

PURPOSE

The incidences of atopic conditions (allergies, asthma, or eczema) and glioma vary by ethnicity. Atopic conditions are inversely associated with gliomas. We conducted a pooled multisite study investigating the associations of atopic conditions with glioma in different race/ethnicity groups.

METHODS

Using glioma cases and healthy controls, unconditional logistic regression was conducted to assess the associations of atopic conditions with glioma separately in white, black, Asian, and Hispanic subpopulations. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

RESULTS

Glioblastoma multiforme cases were less likely than controls to report a history of atopic conditions in whites (OR = 0.46, [95% CI, 0.38-0.54]) and Asians (OR = 0.27, [95% CI, 0.10-0.73]). The same trend was seen when looking at glioma cases of all histologies. An inverse association was not seen in blacks for glioblastoma multiforme or all histologies combined.

CONCLUSIONS

The inverse association between glioma and atopic conditions may vary by ethnicity due to a difference in the biology of atopic conditions in different ethnicities but may be due to chance because of the limitations of small nonwhite sample sizes.

Family history of breast and ovarian cancer and triple negative subtype in hispanic/latina women

Familial breast and ovarian cancer prevalence was assessed among 1150 women of Mexican descent enrolled in a case-only, binational breast cancer study. Logistic regression was conducted to compare odds of triple negative breast cancer (TNBC) to non-TNBC according to family history of breast and breast or ovarian cancer among 914 of these women. Prevalence of breast cancer family history in a first- and first- or second-degree relative was 13.1% and 24.1%, respectively; that for breast or ovarian cancer in a first-degree relative was 14.9%. After adjustment for age and country of residence, women with a first-degree relative with breast cancer were more likely to be diagnosed with TNBC than non-TNBC (OR=1.98; 95% CI, 1.26-3.11). The odds of TNBC compared to non-TNBC were 1.93 (95% CI, 1.26-2.97) for women with a first-degree relative with breast or ovarian cancer. There were non-significant stronger associations between family history and TNBC among women diagnosed at age <50 compared to ≥50 years for breast cancer in a first-degree relative (P-interaction = 0.14) and a first- or second-degree relative (P-interaction = 0.07). Findings suggest that familial breast cancers are associated with triple negative subtype, possibly related to BRCA mutations in Hispanic/Latina women, which are strongly associated with TNBC. Family history is an important tool to identify Hispanic/Latina women who may be at increased risk of TNBC, and could benefit from prevention and early detection strategies.

Abstract 3271: The association between germline genetic variants in the PI3K-AKT-mTOR pathway and breast cancer disease free survival

Background: PI3K-AKT-mTOR pathway activation in breast tumors is associated with poorer breast cancer disease-free survival and decreased responsiveness to tamoxifen and trastuzumab. However, the role of germline variation in this pathway and breast cancer outcomes has not been previously evaluated. We hypothesized that single nucleotide polymorphisms (SNPs) in candidate genes affecting the PI3K-AKT-mTOR signaling pathway may act as genetic modifiers of breast cancer specific outcomes in patients diagnosed with early stage disease.

Methods: We genotyped 106 SNPs in 13 genes (ADIPOQ, IGF1, INS, IRS1, LEP, LEPR, LEPROT, PIK3CA, PIK3R5, PTEN, TSC1, TSC2, and AKT1) in the P13K-AKT-mTOR pathway in a sample of 1020 women with stages I-II breast cancer treated at the MD Anderson Cancer Center between 1985 and 1999 and for whom long term follow-up on recurrence and death were available. The relationship between SNPs and breast cancer disease free survival (DFS) was assessed using Cox regression analysis. After correcting for false discovery rate (0.10) SNPs significantly associated with DFS in any genetic model (additive, dominant or recessive) were included in multivariable analysis.

Results: After adjusting for race, age at diagnosis, tumor stage and treatment, rs1063539 in ADIPOQ (Hazard ratio [HR] 0.40, 95% confidence interval [CI] 0.19 - 0.86), rs11585329 in LEPROT (HR 0.72, 95% CI 0.53 - 0.98), and rs2519757 in TSC1 (HR 0.29, 95% CI 0.09 - 0.91) were associated with improved DFS and rs1520220 in IGF1 (HR 1.56, 95% CI 1.21 - 2.00) and rs2677760 in PIK3CA (HR 1.43, 95% CI 1.70 - 1.92) were associated with worse DFS. The associations were not modified by type of systemic treatment received. The SNPs were not associated with tumor characteristics such as tumor size, lymph node status, nuclear grade, or hormone receptor status.

Conclusion: In this study, germline allelic variation inthe PI3K-AKT-mTOR pathway appears to modify breast cancer patient outcomes. Future studies are needed to replicate our results and to evaluate the relationship between these polymorphisms and activation of the PI3K-AKT-mTOR pathway in breast tumors.

Citation Format: Mala Pande, Melissa Bondy, Kim-Anh Do, Aysegul A. Sahin, Jun Ying, Gordon B. Mills, Patricia Thompson, Abenaa Brewster. The association between germline genetic variants in the PI3K-AKT-mTOR pathway and breast cancer disease free survival. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3271. doi:10.1158/1538-7445.AM2014-3271

A multi-center population-based case-control study of ovarian cancer in African-American women: the African American Cancer Epidemiology Study (AACES)

BACKGROUND

Ovarian cancer (OVCA) is the leading cause of death from gynecological cancer, with poorer survival for African American (AA) women compared to whites. However, little is known about risk factors for OVCA in AA. To study the epidemiology of OVCA in this population, we started a collaborative effort in 10 sites in the US. Here we describe the study and highlight the challenges of conducting a study of a lethal disease in a minority population.

METHODS

The African American Cancer Epidemiology Study (AACES) is an ongoing, population-based case-control study of OVCA in AA in 10 geographic locations, aiming to recruit 850 women with invasive epithelial OVCA and 850 controls age- and geographically-matched to cases. Rapid case ascertainment and random-digit-dialing systems are in place to ascertain cases and controls, respectively. A telephone survey focuses on risk factors as well as factors of particular relevance for AAs. Food-frequency questionnaires, follow-up surveys, biospecimens and medical records are also obtained.

RESULTS

Current accrual of 403 AA OVCA cases and 639 controls exceeds that of any existing study to date. We observed a high proportion (15%) of deceased non-responders among the cases that in part is explained by advanced stage at diagnosis. A logistic regression model did not support that socio-economic status was a factor in advanced stage at diagnosis. Most risk factor associations were in the expected direction and magnitude. High BMI was associated with ovarian cancer risk, with multivariable adjusted ORs and 95% CIs of 1.50 (0.99-2.27) for obese and 1.27 (0.85- 1.91) for morbidly obese women compared to normal/underweight women.

CONCLUSIONS

AACES targets a rare tumor in AAs and addresses issues most relevant to this population. The importance of the study is accentuated by the high proportion of OVCA cases ascertained as deceased. Our analyses indicated that obesity, highly prevalent in this population (>60% of the cases), was associated with increased OVCA risk. While these findings need to be replicated, they suggest the potential for an effective intervention on the risk in AAs. Upon completion of enrollment, AACES will be the largest epidemiologic study of OVCA in AA women.

Family history and breast cancer subtype among women of Mexican descent

41

Background: A family history of breast cancer in a first-degree relative is associated with a 2-fold increase in breast cancer risk; however, breast cancer is a heterogeneous disease and there may be differences in risk profiles driven by tumor subtype or by racial/ethnic group. Methods: We assessed prevalence of familial breast cancer and its association with tumor subtype among 914 women with breast cancer of Mexican descent enrolled in the Ella Study, a case-only, binational (U.S.-Mexico) breast cancer study. Logistic regression was conducted to compare odds of triple negative breast cancers to non triple-negative breast cancers according to family history. Results: The prevalence of family history of breast cancer in a first- or second-degree relative was 24.1%, with 13.1% having an affected first-degree relative. Among participants who were diagnosed at age < 50, prevalence of family history of breast cancer in a first- or second-degree relative was 27.4%. After adjustment for age and country of residence, women with a first-degree relative with breast cancer were significantly more likely to be diagnosed with triple-negative breast cancers compared to non triple-negative breast cancers (OR = 1.98; 95% CI, 1.26-3.11). Similar results were seen for odds of triple-negative breast cancers compared to non-triple negative breast cancers for women with affected first- or second-degree relatives (OR=2.04; 95% CI, 1.40–2.98). The odds of triple-negative breast cancer compared to non-triple negative breast cancer was 1.93 (95% CI, 1.26–2.97) for women with first-degree relatives affected with breast or ovarian cancer. Conclusions: Findings suggest that familial cancers are most likely to be associated with triple negative subtype, supporting etiologic heterogeneity by tumor subtype in this population of Hispanic women. This association may be related to the prevalence of BRCA1 founder mutations in this population, which are strongly associated with triple-negative breast cancers. Identification of such differences in risk factors can help personalize screening and prevention approaches.

Reproductive and hormonal risk profile according to language acculturation and country of residence in the Ella Binational Breast Cancer Study

BACKGROUND

We compared the distribution of breast cancer reproductive and hormonal risk factors by level of acculturation and country of residence in women of Mexican descent.

METHODS

To compare the distribution of breast cancer reproductive and hormonal risk factors by level of acculturation and country of residence in women of Mexican descent, taking into account level of education, we analyzed data on 581 Mexican and 620 Mexican American (MA) women with a history of invasive breast cancer from the Ella Binational Breast Cancer Study. An eight-item language-based acculturation measure was used to classify MA women. Multivariate logistic regression was used to test associations between language acculturation, country of residence, and reproductive and hormonal risk factors.

RESULTS

After adjustment for age and education, compared to women residing in Mexico, English-dominant MAs were significantly more likely to have an earlier age at menarche (<12 years; odds ratio [OR]=2.08; 95% confidence interval [CI], 1.30-3.34), less likely to have a late age at first birth (≥30 years; OR=0.49; 95% CI, 0.25-0.97), and less likely to ever breastfeed (OR=0.13; 95% CI, 0.08-0.21).

CONCLUSIONS

Differences in reproductive and hormonal risk profile according to language acculturation and country of residence are evident; some of these were explained by education. Results support continued efforts to educate Mexican and MA women on screening and early detection of breast cancer along with promotion of modifiable factors, such as breastfeeding.

Association between parity and obesity in Mexican and Mexican-American women: findings from the Ella binational breast cancer study

Obesity at diagnosis of breast cancer is associated with higher all-cause mortality and treatment-associated toxicities. We evaluated the association between parity and obesity in the Ella study, a population of Mexican and Mexican-American breast cancer patients with high parity. Obesity outcomes included body mass index (BMI) ≥30 kg/m(2), waist circumference (WC) ≥35 in (88 cm), and waist-to-hip-ratio (WHR) ≥0.85. Prevalence of obesity ([BMI] ≥ 30 kg/m(2)) was 38.9 %. For WC, the multivariate odds ratio (OR) (95 % confidence interval [CI]) for having WC ≥ 35 inches in women with ≥4 pregnancies relative to those with 1-2 pregnancies was 1.59 (1.01-2.47). Higher parity (≥4 pregnancies) was non-significantly associated with high BMI (OR = 1.10; 95 % CI 0.73-1.67). No positive association was observed for WHR. Our results suggest WC is independently associated with high parity in Hispanic women and may be an optimal target for post-partum weight loss interventions.

Abstract B119: Presence of etiologic heterogeneity by breast tumor subtypes in Hispanic women with unique reproductive risk factor patterns

Background: Published data support the presence of etiologic heterogeneity by breast tumor subtype, but few studies have assessed this in Hispanic populations. Methods: We assessed tumor subtype prevalence and associations between reproductive factors and tumor subtypes in 1041 women of Mexican descent (559 U.S. and 482 Mexico) who participated in the Ella Binational Breast Cancer Study. Multinomial logistic regression comparing human epidermal growth factor receptor 2 positive tumors (HER2+, regardless of ER or PR status) and triple negative breast cancer (TNBC) to hormone receptor positive (HR+) tumors was conducted. Results: A higher proportion of ER- tumors was shown for women in Mexico (40.5%) vs. those in the U.S. (27.2%) and slightly higher proportions of HR+ (61.2% vs. 57.9%) and HER2+ (23.8% vs. 20.3%) tumors were observed in the U.S. compared to Mexico. Prevalence of TNBC was 16.7% overall; the percentage was higher for Mexican vs. U.S. women (19.5% vs. 14.5%). After adjustment for age and country of residence, compared to women with HR+ tumors, those with a later age at first pregnancy were significantly less likely to have TNBC (odds ratio [OR]=0.61; 95% confidence interval [CI]=0.39-0.95), whereas those with ≥ 3 full-term pregnancies were significantly more likely to have TNBC (OR=1.68; 95% CI=1.10-2.55). Patients who reported breastfeeding for &gt;12 months were over twice as likely to have TNBC than HR+ tumors (OR=2.14; 95% CI=1.24–3.68). A lower odds of TNBC was shown for longer menstruation duration, whether prior to first pregnancy (OR=0.78; 95% CI= 0.65–0.93 per 10 years) or prior to menopause (OR=0.79; 95% CI, 0.69–0.91 per 10 years). Associations comparing HER2+ to HR+ tumors were weak or non-existent except for the interval between last full-term pregnancy and breast cancer diagnosis. Conclusions: Findings show etiologic heterogeneity by tumor subtype in a population of Hispanic women with a unique reproductive profile. Given that Hispanic women have higher risk of breast cancer-specific mortality than non-Hispanic whites, our findings add to growing evidence of opposing effects of reproductive factors on breast tumor subtypes, which may partly explain disparities in outcomes.

Citation Format: Maria Elena Martinez, Betsy Wertheim, Loki Natarajan, Richard Schwab, Melissa Bondy, Adrian Daneri-Navarro, Maria Mercedes Meza-Montenegro, Luis Enrique Gutierrez-Millan, Abenaa Brewster, Ian K. Komenaka, Patricia A. Thompson. Presence of etiologic heterogeneity by breast tumor subtypes in Hispanic women with unique reproductive risk factor patterns. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Breast Cancer Research: Genetics, Biology, and Clinical Applications; Oct 3-6, 2013; San Diego, CA. Philadelphia (PA): AACR; Mol Cancer Res 2013;11(10 Suppl):Abstract nr B119.

Reproductive factors, heterogeneity, and breast tumor subtypes in women of mexican descent

BACKGROUND

Published data support the presence of etiologic heterogeneity by breast tumor subtype, but few studies have assessed this in Hispanic populations.

METHODS

We assessed tumor subtype prevalence and associations between reproductive factors and tumor subtypes in 1,041 women of Mexican descent enrolled in a case-only, binational breast cancer study. Multinomial logistic regression comparing HER2(+) tumors and triple-negative breast cancer (TNBC) to luminal A tumors was conducted.

RESULTS

Compared with women with luminal A tumors, those with a later age at first pregnancy were less likely to have TNBC [OR, 0.61; 95% confidence interval (CI), 0.39-0.95], whereas those with three or more full-term pregnancies were more likely to have TNBC (OR, 1.68; 95% CI, 1.10-2.55). A lower odds of TNBC was shown for longer menstruation duration, whether before first pregnancy (OR, 0.78; 95% CI, 0.65-0.93 per 10 years) or menopause (OR, 0.79; 95% CI, 0.69-0.91 per 10 years). Patients who reported breastfeeding for more than 12 months were over twice as likely to have TNBC than luminal A tumors (OR, 2.14; 95% CI, 1.24-3.68). Associations comparing HER2(+) with luminal A tumors were weak or nonexistent except for the interval between last full-term pregnancy and breast cancer diagnosis.

CONCLUSIONS

Findings show etiologic heterogeneity by tumor subtype in a population of Hispanic women with unique reproductive profiles.

IMPACT

Identification of etiologically distinct breast tumor subtypes can further improve our understanding of the disease and help provide personalized prevention and treatment regimens.

Deciphering the 8q24.21 association for glioma

We have previously identified tagSNPs at 8q24.21 influencing glioma risk. We have sought to fine-map the location of the functional basis of this association using data from four genome-wide association studies, comprising a total of 4147 glioma cases and 7435 controls. To improve marker density across the 700 kb region, we imputed genotypes using 1000 Genomes Project data and high-coverage sequencing data generated on 253 individuals. Analysis revealed an imputed low-frequency SNP rs55705857 (P = 2.24 × 10(-38)) which was sufficient to fully capture the 8q24.21 association. Analysis by glioma subtype showed the association with rs55705857 confined to non-glioblastoma multiforme (non-GBM) tumours (P = 1.07 × 10(-67)). Validation of the non-GBM association was shown in three additional datasets (625 non-GBM cases, 2412 controls; P = 1.41 × 10(-28)). In the pooled analysis, the odds ratio for low-grade glioma associated with rs55705857 was 4.3 (P = 2.31 × 10(-94)). rs55705857 maps to a highly evolutionarily conserved sequence within the long non-coding RNA CCDC26 raising the possibility of direct functionality. These data provide additional insights into the aetiological basis of glioma development.

Changes in body mass index and alcohol and tobacco consumption among breast cancer survivors and cancer-free women: a prospective study in the Danish Diet, Cancer and Health Cohort

BACKGROUND

A breast cancer diagnosis has been suggested as a teachable moment when a woman is more open to making healthier lifestyle changes. Little is known about the health behaviour changes women with breast cancer initiate compared to those made by other women.

MATERIAL AND METHODS

We examined changes in body mass index (BMI) and tobacco and alcohol consumption among women with a diagnosis of breast cancer and among cancer-free women. We used data from 23 420 women aged 50-64 years who participated in the Diet, Cancer and Health cohort, of whom 449 were diagnosed with breast cancer between baseline (1993-1997) and follow-up (2000-2002), and 22 971 remained cancer-free. We used multiple linear regression analysis to examine differences in BMI and alcohol and tobacco consumption between the two groups and to examine whether demographic and prognostic factors were associated with behavioural changes in women with breast cancer.

RESULTS

There were no significant differences in changes in BMI, alcohol and tobacco consumption between the two groups. Only in sub-analyses among women who lost weight between baseline and follow-up, women with breast cancer lost more weight than cancer-free women (β = 0.2; CI 0.1; 0.4), but residual confounding from stage cannot be excluded. Among the women with breast cancer we found no significant changes in BMI, alcohol and tobacco consumption by level of education, marital status, chemotherapy, hormone therapy or radiation.

CONCLUSION

Women with breast cancer did not reduce their BMI, or modify their alcohol use or tobacco consumption compared with cancer-free women. This study indicates that guidelines and interventions to change health behaviour are needed after a cancer diagnosis.