Associations of hormone-related factors with breast cancer risk according to hormone receptor status among white and African American women

Analysis of Breast Cancer Screening Results and Influencing Factors of Breast Cancer in Guangdong Province from 2017 to 2021

BACKGROUNDS

Breast cancer screening plays an important role in the early detection, diagnosis and treatment of breast cancer. The aim of this study was to evaluate the screening results and explore the influencing factors of breast cancer detection rate in Guangdong.

METHODS

This cross-sectional study was conducted among 2,024,960 women aged 35-64 in Guangdong Province during 2017-2021. The data about breast cancer screening information were collected from the Guangdong maternal and child health information system. Descriptive statistical analysis was used to explain demographic characteristics and results of breast cancer screening. The generalized linear regression model was applied to analyze the related influencing factors of breast cancer detection rate.

RESULTS

The estimated detection rate of breast cancer in Guangdong Province is 70.32/105, with an early diagnosis rate of 82.06%. After adjusting covariates, those women with older age (45-55 [OR (95% CI) 2.174 (1.872, 2.526)], 55-65 [OR (95% CI) 2.162 (1.760, 2.657)]), education for high school ([OR (95% CI) 1.491 (1.254, 1.773)]) and older age at first birth ([OR (95% CI) 1.632 (1.445, 1.844)]) were more likely to have higher detection rate of breast cancer. No history of surgery or biopsy ([OR (95% CI) 0.527 (0.387, 0.718)]), no history of breast cancer check ([OR (95% CI) 0.873 (0.774, 0.985)]) and no family history of breast cancer ([OR (95% CI) 0.255 (0.151, 0.432)]) women were more likely to screen negative for breast cancer (P < 0.05).

CONCLUSION

The detection rate of breast cancer in screening showed an increasing trend year by year in Guangdong Province. Older age, education for high school and older age at first birth were risk factors for breast cancer detection rate, while no surgery or biopsy history, no family history of breast cancer and no history of breast cancer check were protective factors.

The Military Health System: Minimizing Disparities in Breast Cancer Treatment

BACKGROUND

The Military Health System (MHS) is a universal health care system, in which health care disparities are theoretically minimized. This study aimed to identify disparities and assess their impact on the initiation of timely treatment for breast cancer within a universally insured population.

METHODS

A retrospective cohort study was performed to evaluate the treatment of female breast cancer patients ≥18 years of age within the MHS from January 1, 2014, to December 31, 2018. Incident breast cancer was defined as ≥2 breast cancer diagnoses without a prior diagnosis of breast cancer during the three continuous years before index diagnosis. Time from index diagnosis to initial treatment was calculated and dichotomized as receiving treatment within a clinically acceptable time course. Poisson regression was used to estimate relative risk (RR) with 95% CIs.

RESULTS

Among the 30,761 female breast cancer patients identified in the MHS, only 6% of patients had a prolonged time to initial treatment. Time to initial treatment decreased during the study period from a mean (SD) of 63.2 (152.0) days in 2014 to 37.1 (28.8) days in 2018 (P < 0.0001). Age, region, and military characteristics remained significantly associated with receiving timely treatment even after the adjustment of confounders. Patients 70-79 years old were twice as likely as 18-39 years olds to receive timely treatment (RR: 2.0100, 95% CI, 1.52-2.6563, P < 0.0001). Senior officers and their dependents were more likely to receive timely initial treatment compared to junior enlisted patients and their dependents (RR: 1.5956, 95% CI, 1.2119-2.1005, P = 0.004).

CONCLUSIONS

There have been significant improvements in the timely initiation of breast cancer treatment within the MHS. However, demographic and socioeconomic disparities can be identified that affect the timely initiation of therapy.

A pooled case-only analysis of obesity and breast cancer subtype among Black women in the southeastern United States

PURPOSE

To evaluate the association between obesity and the relative prevalence of tumor subtypes among Black women with breast cancer (BC).

METHODS

We conducted a pooled case-only analysis of 1,793 Black women with invasive BC recruited through three existing studies in the southeastern US. Multivariable case-only polytomous logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association between obesity, measured by pre-diagnostic body mass index (BMI), and human epidermal growth factor receptor 2 + (HER2 +) and triple negative BC (TNBC) subtype relative to hormone receptor (HR) + /HER2- status (referent).

RESULTS

Among 359 premenopausal women, 55.4% of cases were HR + /HER2 -, 20.1% were HER2 + , and 24.5% were TNBC; corresponding percentages among 1,434 postmenopausal women were 59.3%, 17.0%, and 23.6%. Approximately, 50-60% of both pre- and postmenopausal women were obese (BMI > 30 kg/m²), regardless of BC subtype. We did not observe a significant association between obesity and BC subtype. Among postmenopausal women, class I obesity (BMI 35 + kg/m²) was not associated with the development of HER2 + BC (OR 0.69; 95% CI 0.42-1.14) or TNBC (OR 0.93; 95% CI 0.60-1.45) relative to HR + /HER2- tumors. Corresponding estimates among premenopausal women were 1.03 (95% CI 0.43-2.48) and 1.13 (95% CI 0.48-2.64).

CONCLUSION

In this large study of Black women with BC, there was no evidence of heterogeneity of BMI by BC subtype.

Racial/ethnic differences in postmenopausal breast cancer risk by hormone receptor status: The multiethnic cohort study

There are racial/ethnic differences in the incidence of hormone receptor positive and negative breast cancer. To understand why these differences exist, we investigated associations between hormone-related factors and breast cancer risk by race/ethnicity in the Multiethnic Cohort (MEC) Study. Among 81 511 MEC participants (Native Hawaiian, Japanese American, Latina, African American and White women), 3806 estrogen receptor positive (ER+) and 828 ER- incident invasive breast cancers were diagnosed during a median of 21 years of follow-up. We used Cox proportional hazards regression models to calculate associations between race/ethnicity and breast cancer risk, and associations between hormone-related factors and breast cancer risk by race/ethnicity. Relative to White women, ER+ breast cancer risk was higher in Native Hawaiians and lower in Latinas and African Americans; ER- disease risk was higher in African Americans. We observed interaction with race/ethnicity in associations between oral contraceptive use (OC; Pint .03) and body mass index (BMI; Pint .05) with ER+ disease risk; ever versus never OC use increased risk only in Latinas and positive associations for obese versus lean BMI were strongest in Japanese Americans. For ER- disease risk, associations for OC use, particularly duration of use, were strongest for African Americans (Pint .04). Our study shows that associations of OC use and obesity with ER+ and ER- breast cancer risk differ by race/ethnicity, but established risk factors do not fully explain racial/ethnic differences in risk. Further studies are needed to identify factors to explain observed racial/ethnic differences in breast cancer incidence.

Cumulative menstrual months and breast cancer risk by hormone receptor status and ethnicity: The Breast Cancer Etiology in Minorities Study

Reproductive and hormonal factors may influence breast cancer risk via endogenous estrogen exposure. Cumulative menstrual months (CMM) can be used as a surrogate measure of this exposure. Using harmonized data from four population-based breast cancer studies (7284 cases and 7242 controls), we examined ethnicity-specific associations between CMM and breast cancer risk using logistic regression, adjusting for menopausal status and other risk factors. Higher CMM was associated with increased breast cancer risk in non-Hispanic Whites, Hispanics and Asian Americans regardless of menopausal status (all FDR adjusted P trends = .0004), but not in African Americans. In premenopausal African Americans, there was a suggestive trend of lower risk with higher CMM. Stratification by body mass index (BMI) among premenopausal African American women showed a nonsignificant positive association with CMM in nonobese (BMI <30 kg/m² ) women and a significant inverse association in obese women (OR per 50 CMM = 0.56, 95% CI 0.37-0.87, P_trend  = .03). Risk patterns were similar for hormone receptor positive (HR+; ER+ or PR+) breast cancer; a positive association was found in all premenopausal and postmenopausal ethnic groups except in African Americans. HR- (ER- and PR-) breast cancer was not associated with CMM in all groups combined, except for a suggestive positive association among premenopausal Asian Americans (OR per 50 CMM = 1.33, P = .07). In summary, these results add to the accumulating evidence that established reproductive and hormonal factors impact breast cancer risk differently in African American women compared to other ethnic groups, and also differently for HR- breast cancer than HR+ breast cancer.

A Pooled Case-only Analysis of Reproductive Risk Factors and Breast Cancer Subtype Among Black Women in the Southeastern United States

BACKGROUND

We investigated the association between reproductive risk factors and breast cancer subtype in Black women. On the basis of the previous literature, we hypothesized that the relative prevalence of specific breast cancer subtypes might differ according to reproductive factors.

METHODS

We conducted a pooled analysis of 2,188 (591 premenopausal, 1,597 postmenopausal) Black women with a primary diagnosis of breast cancer from four studies in the southeastern United States. Breast cancers were classified by clinical subtype. Case-only polytomous logistic regression models were used to estimate ORs and 95% confidence intervals (CI) for HER2⁺ and triple-negative breast cancer (TNBC) status in relation to estrogen receptor-positive (ER⁺)/HER2^- status (referent) for reproductive risk factors.

RESULTS

Relative to women who had ER⁺/HER2^- tumors, women who were age 19-24 years at first birth (OR, 1.78; 95% CI, 1.22-2.59) were more likely to have TNBC. Parous women were less likely to be diagnosed with HER2⁺ breast cancer and more likely to be diagnosed with TNBC relative to ER⁺/HER2^- breast cancer. Postmenopausal parous women who breastfed were less likely to have TNBC [OR, 0.65 (95% CI, 0.43-0.99)].

CONCLUSIONS

This large pooled study of Black women with breast cancer revealed etiologic heterogeneity among breast cancer subtypes.

IMPACT

Black parous women who do not breastfeed are more likely to be diagnosed with TNBC, which has a worse prognosis, than with ER⁺/HER2^- breast cancer.

Reproductive factors and risk of breast cancer in black South African women

PURPOSE

Breast cancer (BC) is increasing in black South African women, but few studies have investigated its risk factors.

METHODS

We conducted an analysis of reproductive factors and BC risk in the South African Breast Cancer (SABC) study-a population-based case-control study of black South African women from Soweto that included 399 cases and 399 matched controls. Information on lifestyle and reproductive history was obtained by interviews. Conditional logistic regression was used to determine the association of reproductive factors with BC, adjusting for potential confounding factors.

RESULTS

Seventy-five percent of all BC cases were ER+, 66% PR+, 30% HER2+, and 16% TN. None of the reproductive variables were associated with BC overall or by subtype in the overall population, nor in pre- (n = 135 cases) or in post-menopausal women separately. In HIV-negative pre-menopausal women (n = 97 cases), later age at first pregnancy and longer time between menarche and first full-time pregnancy were inversely related to BC risk (OR 0.89 (95% CI 0.82-0.97; and 0.93 95% CI 0.86-1.01, respectively).

CONCLUSION

In this population of black South African women, reproductive factors were not associated with BC risk.

Menstrual and reproductive characteristics and breast cancer risk by hormone receptor status and ethnicity: The Breast Cancer Etiology in Minorities study

We pooled multiethnic data from four population-based studies and examined associations of menstrual and reproductive characteristics with breast cancer (BC) risk by tumor hormone receptor (HR) status [defined by estrogen receptor (ER) and progesterone receptor (PR)]. We estimated odds ratios and 95% confidence intervals using multivariable logistic regression, stratified by age (<50, ≥50 years) and ethnicity, for 5,186 HR+ (ER+ or PR+) cases, 1,365 HR- (ER- and PR-) cases and 7,480 controls. For HR+ BC, later menarche and earlier menopause were associated with lower risk in non-Hispanic whites (NHWs) and Hispanics, and higher parity and longer breast-feeding were associated with lower risk in Hispanics and Asian Americans, and suggestively in NHWs. Positive associations with later first full-term pregnancy (FTP), longer interval between menarche and first FTP and shorter time since last FTP were limited to younger Hispanics and Asian Americans. Except for nulliparity, reproductive characteristics were not associated with risk in African Americans. For HR- BC, lower risk was associated with later menarche, except in African Americans and older Asian Americans and with longer breast-feeding in Hispanics and Asian Americans only. In younger African Americans, HR- BC risk associated with higher parity (≥3 vs. 1 FTP) was increased fourfold in women who never breast-fed, but not in those with a breast-feeding history, suggesting that breast-feeding may mitigate the adverse effect of higher parity in younger African American women. Further work needs to evaluate why menstrual and reproductive risk factors vary in importance according to age and ethnicity.

Pubertal mammary development as a "susceptibility window" for breast cancer disparity

Factors such as socioeconomic status, age at menarche and childbearing patterns are components that have been shown to influence mammary gland development and establish breast cancer disparity. Pubertal mammary gland development is selected as the focus of this review, as it is identified as a "window of susceptibility" for breast cancer risk and disparity. Here we recognize non-Hispanic White, African American, and Asian American women as the focus of breast cancer disparity, in conjunction with diets associated with changes in breast cancer risk. Diets consisting of high fat, N-3 polyunsaturated fatty acids, N-6 polyunsaturated fatty acids, as well as obesity and the Western diet have shown to lead to changes in pubertal mammary gland development in mammalian models, therefore increasing the risk of breast cancer and breast cancer disparity. While limited intervention strategies are offered to adolescents to mitigate development changes and breast cancer risk, the prominent solution to closing the disparity among the selected population is to foster lifestyle changes that avoid the deleterious effects of unhealthy diets.

Number of Risky Lifestyle Behaviors and Breast Cancer Risk

Background

Lifestyle factors are associated with overall breast cancer risk, but less is known about their associations, alone or jointly, with risk of specific breast cancer subtypes.

Methods

We conducted a case-control subjects study nested within a cohort of women who participated in the Norwegian Breast Cancer Screening Program during 2006-2014 to examine associations between risky lifestyle factors and breast cancer risk. In all, 4402 breast cancer cases subjects with information on risk factors and hormone receptor status were identified. Conditional logistic regression was used to estimate odds ratios (ORs), with 95% confidence intervals (CIs), in relation to five risky lifestyle factors: body mass index (BMI) of 25 kg/m² or greater, three or more glasses of alcoholic beverages per week, ever smoking, fewer than four hours of physical activity per week, and ever use of menopausal hormone therapy. Analyses were adjusted for education, age at menarche, number of pregnancies, and menopausal status. All statistical tests were two-sided.

Results

Compared with women with no risky lifestyle behaviors, those with five had 85% (OR = 1.85, 95% CI = 1.42 to 2.42, P _trend < .0001) increased risk of breast cancer overall. This association was limited to luminal A-like (OR = 2.20, 95% CI = 1.55 to 3.12, P _trend < .0001) and luminal B-like human epidermal growth factor receptor 2 (HER2)-positive (OR = 1.66, 95% CI = 0.61 to 4.54, P _trend < .004) subtypes. Number of risky lifestyle factors was not associated with increased risk of luminal B-like HER2-negative, HER2-positive, or triple-negative subtypes (P _trend > .18 for all).

Conclusions

Number of risky lifestyle factors was positively associated with increased risk for luminal A-like and luminal B-like HER2-positive breast cancer.

Identification of differentially expressed genes in human breast cancer cells induced by 4-hydroxyltamoxifen and elucidation of their pathophysiological relevance and mechanisms

While tamoxifen (TAM) is used for treating estrogen receptor (ER)a-positive breast cancer patients, its anti-breast cancer mechanisms are not completely elucidated. This study aimed to examine effects of 4-hydroxyltamoxifen (4-OH-TAM) on ER-positive (ER⁺) breast cancer MCF-7 cell growth and gene expression profiles. MCF-7 cell growth was inhibited by 4-OH-TAM dose-dependently with IC₅₀ of 29 μM. 332 genes were up-regulated while 320 genes were down-regulated. The mRNA levels of up-regulated genes including STAT1, STAT2, EIF2AK2, TGM2, DDX58, PARP9, SASH1, RBL2 and USP18 as well as down-regulated genes including CCDN1, S100A9, S100A8, ANXA1 and PGR were confirmed by quantitative real-time PCR (qRT-PCR). In human breast tumor tissues, mRNA levels of EIF2Ak2, USP18, DDX58, RBL2, STAT2, PGR, S1000A9, and CCND1 were significantly higher in ER⁺- than in ER^--breast cancer tissues. The mRNA levels of EIF2AK2, TGM2, USP18, DDX58, PARP9, STAT2, STAT1, PGR and CCND1 were all significantly higher in ER⁺-tumor tissues than in their corresponding tumor-adjacent tissues. These genes, except PGR and CCND1 which were down-regulated, were also up-regulated in ER⁺ MCF-7 cells by 4-OH-TAM. Total 14 genes mentioned above are involved in regulation of cell proliferation, apoptosis, cell cycles, and estrogen and interferon signal pathways. Bioinformatics analysis also revealed other novel and important regulatory factors that are associated with these genes and involved in the mentioned functional processes. This study has paved a foundation for elucidating TAM anti-breast cancer mechanisms in E2/ER-dependent and independent pathways.

Race, Menopausal Hormone Therapy, and Invasive Breast Cancer in the Carolina Breast Cancer Study

PURPOSE

The use of combined estrogen-progestin menopausal hormone therapy (MHT) has been shown to increase the risk of breast cancer, however, recent observational studies have suggested that the association between MHT and breast cancer may be modified by race. The objective of this study was to investigate the association between MHT use and incidence of invasive breast cancer in Black and White women aged ≥40 years at diagnosis after accounting for racial differences in patterns of MHT use and formulation.

METHODS

Data from the Carolina Breast Cancer Study, a population-based case-control study of Black and White women in North Carolina conducted between 1993 and 2001, was used to analyze 1474 invasive breast cancer cases and 1339 controls using unconditional logistic regression.

RESULTS

Black women were less likely than White women to use any MHT and were more likely to use an unopposed-estrogen formulation. Combined estrogen-progestin MHT use was associated with a greater odds of breast cancer in White (adjusted odds ratio [OR] 1.48, 95% confidence interval [CI]: 1.03-2.13) and Black (OR 1.43, 95% CI: 0.76-2.70) women, although the estimate in Black women was imprecise. In contrast, use of unopposed-estrogen MHT among women with prior hysterectomy was not associated with breast cancer in women of either race.

CONCLUSION

The association between MHT and invasive breast cancer appears to be similar in both Black and White women after accounting for differences in formulation and prior hysterectomy. These findings emphasize the importance of accounting for MHT formulation in race-stratified analyses of breast cancer risk.

Parity, hormones and breast cancer subtypes - results from a large nested case-control study in a national screening program

Background

Breast cancer comprises several molecular subtypes with different prognoses and possibly different etiology. Reproductive and hormonal factors are associated with breast cancer overall, and with luminal subtypes, but the associations with other subtypes are unclear. We used data from a national screening program to conduct a large nested case-control study.

Methods

We conducted a nested case-control study on participants in the Norwegian Breast Cancer Screening Program in 2006 − 2014. There was information on estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) for 4748 cases of breast cancer. Breast cancer subtypes were defined as luminal A-like (ER+ PR+ HER2-), luminal B-like (ER+ PR- HER2- or ER+ PR+/PR-HER2+), HER2-positive (ER- PR- HER2+) and triple-negative (ER- PR- HER2-). Conditional logistic regression was used to estimate odds ratios (ORs) of breast cancer associated with age at first birth, number of pregnancies, oral contraceptive use, intrauterine devices and menopausal hormone therapy. Analyses were adjusted for age, body mass index, education, age at menarche, number of pregnancies and menopausal status.

Results

Number of pregnancies was inversely associated with relative risk of luminal-like breast cancers (p-trend ≤0.02), and although not statistically significant, with HER2-positive (OR = 0.60, 95% CI 0.31–1.19) and triple-negative cancer (OR = 0.70, 95% CI 0.41–1.21). Women who had ≥4 pregnancies were at >40% lower risk of luminal-like and HER2-positive cancers than women who had never been pregnant. However, there was a larger discrepancy between tumor subtypes with menopausal hormone use. Women who used estrogen and progesterone therapy (EPT) had almost threefold increased risk of luminal A-like cancer (OR = 2.92, 95% CI 2.36–3.62) compared to never-users, but were not at elevated risk of HER2-positive (OR = 0.88, 95% CI 0.33–2.30) or triple-negative (OR = 0.92, 95% CI 0.43 − 1.98) subtypes.

Conclusions

Reproductive factors were to some extent associated with all subtypes; the strongest trends were with luminal-like subtypes. Hormone therapy use was strongly associated with risk of luminal-like breast cancer, and less so with risk of HER2-positive or triple-negative cancer. There are clearly some, but possibly limited, etiologic differences between subtypes, with the greatest contrast between luminal A-like and triple-negative subtypes.

Trial registration

Not applicable.

Differential Patterns of Risk Factors for Early-Onset Breast Cancer by ER Status in African American Women

BACKGROUND

Given the disproportionately high incidence of early-onset breast cancer and aggressive subtypes, such as estrogen receptor (ER)-negative tumors, in African American (AA) women, elucidation of risk factors for early onset of specific subtypes of breast cancer is needed.

METHODS

We evaluated associations of reproductive, anthropometric, and other factors with incidence of invasive breast cancer by age at onset (<45, ≥45) in 57,708 AA women in the prospective Black Women's Health Study. From 1995 to 2013, we identified 529 invasive breast cancers among women <45 years of age (151 ER^-, 219 ER⁺) and 1,534 among women ≥45 years (385 ER^-, 804 ER⁺). We used multivariable Cox proportional hazards regression to estimate hazard ratios (HRs) for associations by age and ER status.

RESULTS

Higher parity, older age at first birth, never having breastfed, and abdominal adiposity were associated with increased risk of early-onset ER^- breast cancer: HRs were 1.71 for ≥3 births versus one birth; 2.29 for first birth after age 25 versus <20 years; 0.61 for ever having breastfed versus never; and 1.64 for highest versus lowest tertile of waist-to-hip ratio. These factors were not associated with ER^- cancer in older women or with ER⁺ cancer regardless of age.

CONCLUSIONS

Differences in risk factors by ER subtype were observed for breast cancer diagnosed before the age of 45 years.

IMPACT

Etiological heterogeneity by tumor subtype in early-onset breast cancer, in combination with a higher prevalence of the risk factors in AA women, may explain, in part, racial disparities in breast cancer incidence. Cancer Epidemiol Biomarkers Prev; 26(2); 270-7. ©2016 AACR.

Rate of Distant Metastases on 18F-FDG PET/CT at Initial Staging of Breast Cancer: Comparison of Women Younger and Older Than 40 Years

Women who have breast cancer and are younger than 40 y have a poorer outcome than older women. A higher rate of undetected metastases at the time of diagnosis in younger women has been proposed to account for this difference. Our main objective was to test this hypothesis by comparing the distant metastasis rate (DMR) on initial ¹⁸F-FDG PET/CT in a group of breast cancer patients younger than 40 y (<40 y group) with that in a group of breast cancer patients older than 40 y (≥40 y group). An assessment of associations between distant metastases and tumor characteristics was a second objective of the present study.

METHODS

A retrospective single-institution study was performed on women who had breast cancer and no prior malignancy, who were asymptomatic for metastatic lesions on initial clinical examination, and who had initial ¹⁸F-FDG PET/CT within 3 mo after pathologic breast cancer diagnosis and before initial treatment. On the basis of these criteria, data for 2 groups of women differing only in age (<40 y and ≥40 y) were extracted from the hospital information system of Curie Institute-Paris. ¹⁸F-FDG PET/CT examinations were reviewed, and the DMR was recorded for each clinical stage subgroup (stages I-III).

RESULTS

For each group (<40 y and ≥40 y), 107 patients were included, with the same number of patients in each clinical stage subgroup (12 stage I patients, 32 stage IIA patients, 30 stage IIB patients, and 33 stage III patients). The ages of the patients (mean ± SD) were 34.5 ± 4.0 y (<40 y group) and 56.0 ± 10.7 y (≥40 y group). No significant difference in DMRs was observed between the <40 y group and the ≥40 y group (DMRs, 21% and 22%, respectively; P = 1). The DMRs in patients not selected for age were 8% for stage I, 11% for stage IIA, 15% for stage IIB, and 44% for stage III.

CONCLUSION

The DMR was not significantly higher in younger breast cancer patients (<40 y) than in older breast cancer patients (≥40 y), ruling out the assumption that undetected metastases at diagnosis explain the poorer outcome of younger women. However, our results highlight the high yield of ¹⁸F-FDG PET/CT for initial breast cancer staging, even in stage II patients, whatever their age.

Rampant centrosome amplification underlies more aggressive disease course of triple negative breast cancers

Centrosome amplification (CA), a cell-biological trait, characterizes pre-neoplastic and pre-invasive lesions and is associated with tumor aggressiveness. Recent studies suggest that CA leads to malignant transformation and promotes invasion in mammary epithelial cells. Triple negative breast cancer (TNBC), a histologically-aggressive subtype shows high recurrence, metastases, and mortality rates. Since TNBC and non-TNBC follow variable kinetics of metastatic progression, they constitute a novel test bed to explore if severity and nature of CA can distinguish them apart. We quantitatively assessed structural and numerical centrosomal aberrations for each patient sample in a large-cohort of grade-matched TNBC (n = 30) and non-TNBC (n = 98) cases employing multi-color confocal imaging. Our data establish differences in incidence and severity of CA between TNBC and non-TNBC cell lines and clinical specimens. We found strong correlation between CA and aggressiveness markers associated with metastasis in 20 pairs of grade-matched TNBC and non-TNBC specimens (p < 0.02). Time-lapse imaging of MDA-MB-231 cells harboring amplified centrosomes demonstrated enhanced migratory ability. Our study bridges a vital knowledge gap by pinpointing that CA underlies breast cancer aggressiveness. This previously unrecognized organellar inequality at the centrosome level may allow early-risk prediction and explain higher tumor aggressiveness and mortality rates in TNBC patients.

Postmenopausal Female Hormone Use and Estrogen Receptor-Positive and -Negative Breast Cancer in African American Women

BACKGROUND

Use of estrogen with progestin (combination therapy) is associated with increased incidence of estrogen receptor-positive (ER+) breast cancer in observational studies and randomized trials among postmenopausal white women. Whether this is also the case among African American women is not established.

METHODS

Using data from the AMBER consortium collected from 1993 to 2013, we assessed use of estrogen alone and of combination therapy in relation to ER+ and ER-negative (ER-) breast cancer risk in postmenopausal African American women, based on 1132 ER+ case patients, 512 ER- case patients, and 6693 control patients. Odds ratios (ORs) and confidence intervals (CIs) were estimated using multinomial logistic regression with control for breast cancer risk factors.

RESULTS

Forty-seven percent of control patients had used estrogen alone, combination therapy, or both. The odds ratio for ER+ breast cancer associated with combination use, relative to never use of either estrogen alone or combination therapy, was 1.50 (95% CI = 1.25 to 1.79). The increase was greater for recent (OR = 1.55, 95% CI = 1.21 to 1.99) and long-term use (OR = 1.75, 95% CI = 1.13 to 2.73) and among nonobese women (OR = 1.91, 95% CI = 1.29 to 2.83). Breast cancer risk was increased regardless of the interval between onset of menopause and initiation of combination use (OR = 1.43, 95% CI = 1.11 to 1.85, for <5 year interval; OR = 1.78, 95% CI = 1.34 to 2.37, for ≥5 year interval). Combination use was not associated with risk of ER- breast cancer, and use of estrogen alone was not associated with risk of either ER+ or ER- breast cancer.

CONCLUSION

Use of estrogen with progestin increases risk of ER+ breast cancer in African American women. A decrease in use would be expected to reduce the number of ER+ cancers.

Copy Number Analysis of the DLX4 and ERBB2 Genes in South African Breast Cancer Patients

Breast cancer is one of the main causes of cancer death among South African women. Although several risk factors can be attributed to the observed high mortality rate, the biology of the tumors is not extensively investigated. Copy number gain of the DLX4 homeobox gene has been observed in breast cancer in association with poor prognosis and specific racial groups. Therefore, we aimed to assess the copy number and prognostic role of DLX4 in breast cancer from South African patients. Due to the co-location of ERBB2 and DLX4 in the 17q21 region, its copy number was also evaluated. Our results in the analysis of 66 cases demonstrated copy number gains of DLX4 and ERBB2 in 24.1 and 29.7% of the cases, respectively. Linear regression analysis showed no dependency between the copy number alterations in these genes. Although not significant, patients with DLX4 and ERBB2 gains presented a higher frequency of advanced-grade tumors. In addition, copy number alterations of these genes were not significantly differently observed in the 3 main racial groups of the Western Cape population: Colored, White, and Black. These findings indicate that gains of DLX4 and ERBB2 occur in South African breast cancer patients irrespectively of their race and factors known to influence prognosis.

Important Role of Menarche in Development of Estrogen Receptor-Negative Breast Cancer in African American Women

BACKGROUND

Menarche is a critical time point for diverging fates of mammary cells of origin. African American women have young age at menarche, which could be associated with their high rates of estrogen receptor-negative (ER-) breast cancer.

METHODS

In the AMBER Consortium, using harmonized data from 4426 African American women with breast cancer and 17 474 controls, we used polytomous logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for ages at menarche and first live birth (FLB), and the interval between, in relation to ER+ and ER- breast cancer. All statistical tests were two-sided.

RESULTS

Risk of ER- breast cancer was reduced with later age at menarche among both parous and nulliparous women (≥15 vs <11 years OR = 0.62, 95% CI = 0.48 to 0.81 and OR = 0.56, 95% CI = 0.29 to 1.10, respectively), with no effect of age at FLB. For ER+ breast cancer, the inverse association was weaker among nulliparous women. While longer intervals between menarche and FLB were associated with increased risk of ER+ breast cancer in a dose-response fashion (OR for 20 year interval = 1.39, 95% CI = 1.08 to 1.79, P trend = .003), ER- risk was only increased for intervals up to 14 years and not beyond (P trend = .33).

CONCLUSIONS

While ER- breast cancer risk was markedly reduced in women with a late age at menarche, there was not a clear pattern of increased risk with longer interval between menarche and FLB, as was observed for ER+ breast cancer. These findings indicate that etiologic pathways involving adolescence and pregnancy may differ for ER- and ER+ breast cancer.

Annual Report to the Nation on the Status of Cancer, 1975-2011, Featuring Incidence of Breast Cancer Subtypes by Race/Ethnicity, Poverty, and State

BACKGROUND

The American Cancer Society (ACS), Centers for Disease Control and Prevention (CDC), National Cancer Institute (NCI), and North American Association of Central Cancer Registries (NAACCR) collaborate annually to produce updated, national cancer statistics. This Annual Report includes a focus on breast cancer incidence by subtype using new, national-level data.

METHODS

Population-based cancer trends and breast cancer incidence by molecular subtype were calculated. Breast cancer subtypes were classified using tumor biomarkers for hormone receptor (HR) and human growth factor-neu receptor (HER2) expression.

RESULTS

Overall cancer incidence decreased for men by 1.8% annually from 2007 to 2011 [corrected]. Rates for women were stable from 1998 to 2011. Within these trends there was racial/ethnic variation, and some sites have increasing rates. Among children, incidence rates continued to increase by 0.8% per year over the past decade while, like adults, mortality declined. HR+/HER2- breast cancers, the subtype with the best prognosis, were the most common for all races/ethnicities with highest rates among non-Hispanic white women, local stage cases, and low poverty areas (92.7, 63.51, and 98.69 per 100000 non-Hispanic white women, respectively). HR+/HER2- breast cancer incidence rates were strongly, positively correlated with mammography use, particularly for non-Hispanic white women (Pearson 0.57, two-sided P < .001). Triple-negative breast cancers, the subtype with the worst prognosis, were highest among non-Hispanic black women (27.2 per 100000 non-Hispanic black women), which is reflected in high rates in southeastern states.

CONCLUSIONS

Progress continues in reducing the burden of cancer in the United States. There are unique racial/ethnic-specific incidence patterns for breast cancer subtypes; likely because of both biologic and social risk factors, including variation in mammography use. Breast cancer subtype analysis confirms the capacity of cancer registries to adjust national collection standards to produce clinically relevant data based on evolving medical knowledge.

Estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 status in invasive breast cancer: a 3,198 cases study at National Cancer Center, China

Smears from paraffin sections from 3,198 cases of surgical resection mammary carcinomas were assessed immunohistochemically for estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) expressions in National Cancer Center (NCC), China, to explore the correlation of these markers to each other, to tumor histologic subtype, and to explore breast cancer four molecular subtypes clinicopathological characteristics. Pathology material of surgical resection patients presenting to NCC during July 1, 2010-July 1, 2012 were reviewed for patients' age, tumor size, subtype, grade, and ER, PR, HER2 immunohistochemistry (IHC) status. For HER2 IHC 2+ score cases, fluorescence in situ hybridization was used, as the 2007 American society of clinical oncology/college of American pathologists guidelines. There were 3,198 cases, with a median age of 51 years, a mean tumor size of 2.1 cm, and 42.3 % lymph node positivity. Of all cases, 2,506 (78.4 %) were ER+, 2,548 (79.7 %) were PR+, and 816 (25.5 %) were HER2+. Among the four molecular subtypes of breast cancer, luminal A were the majority accounting for 65.3 %, and triple-negative breast cancer accounted for 9.2 %. ER, PR, and HER2 status showed a direct correlation to tumor onset age, tumor type, and grade of ductal carcinoma. Meanwhile the four subtypes of breast cancer differed from onset age, tumor size, lymph node metastasis, and tumor grade. This study was an important documentation of Chinese breast cancer patients and the report would serve as a baseline for other future studies.