Hormone replacement therapy and risk of breast cancer with a favorable histology: results of the Iowa Women's Health Study

Is There a Special Role for Ovarian Hormones in the Pathogenesis of Lobular Carcinoma?

Lobular carcinoma represent the most common special histological subtype of breast cancer, with the majority classed as hormone receptor positive. Rates of invasive lobular carcinoma in postmenopausal women have been seen to increase globally, while other hormone receptor-positive breast cancers proportionally have not followed the same trend. This has been linked to exposure to exogenous ovarian hormones such as hormone replacement therapy. Reproductive factors resulting in increased lifetime exposure to endogenous ovarian hormones have also been linked to an increased risk of lobular breast cancer, and taken together, these data make a case for the role of ovarian hormones in the genesis and progression of the disease. In this review, we summarize current understanding of the epidemiological associations between ovarian hormones and lobular breast cancer and highlight mechanistic links that may underpin the etiology and biology.

DCIS and LCIS: Are the Risk Factors for Developing In Situ Breast Cancer Different?

Ductal carcinoma in situ (DCIS) is widely accepted as a precursor of invasive ductal carcinoma (IDC). Lobular carcinoma in situ (LCIS) is considered a risk factor for invasive lobular carcinoma (ILC), and it is unclear whether LCIS is also a precursor. Therefore, it would be expected that similar risk factors predispose to both DCIS and IDC, but not necessarily LCIS and ILC. This study examined associations with risk factors using data from 3075 DCIS cases, 338 LCIS cases, and 1584 controls aged 35-60, recruited from the UK-based GLACIER and ICICLE case-control studies between 2007 and 2012. Analysis showed that breastfeeding in parous women was protective against DCIS and LCIS, which is consistent with research on invasive breast cancer (IBC). Additionally, long-term use of HRT in post-menopausal women increased the risk of DCIS and LCIS, with a stronger association in LCIS, similar to the association with ILC. Contrary to findings with IBC, parity and the number of births were not protective against DCIS or LCIS, while oral contraceptives showed an unexpected protective effect. These findings suggest both similarities and differences in risk factors for DCIS and LCIS compared to IBC and that there may be justification for increased breast surveillance in post-menopausal women taking long-term HRT.

Dose-dependent relation between metformin and the risk of hormone receptor-positive, her2-negative breast cancer among postmenopausal women with type-2 diabetes

PURPOSE

Metformin has demonstrated a chemoprotective effect in breast cancer but there is limited evidence on the effect of cumulative exposure to metformin and the risk of hormone receptor-positive and human epidermal growth factor receptor 2-negative (HR + /HER2-) breast cancer. This study assessed this risk with dose and intensity of metformin in postmenopausal women with type-2 diabetes mellitus (T2DM).

METHODS

This nested case-control study used the Surveillance, Epidemiology, and End Results-Medicare data (2008-2015). Cohort entry was the date of incident T2DM diagnosis. Cases were those diagnosed with HR + /HER2- breast cancer (event date) as their first/only cancer. Non-cancer T2DM controls were matched using variable-ratio-matching. Cumulative dose and average intensity of metformin were measured during the 1-year lookback period. Dose(mg) was categorized as: (1)0, (2)0-30,000, (3)30,001-136,000, (4)136,001-293,000, and (5) > 293,000, and intensity(mg/day) as: 0, 1-500, and > 500. Covariates were conceptualized using the Andersen Behavioral Model. Conditional logistic regression was used to assess the risk of HR + /HER2- breast cancer with metformin-use.

RESULTS

There were 690 cases and 2747 controls. The median duration of T2DM was 1178 days in controls and 1180 days in cases. Higher cumulative dose categories: 4 (adjusted odds ratio(aOR) = 0.72, 95% CI 0.55-0.95,p = 0.02), and 5 (OR = 0.60, 95% CI 0.42-0.85,p < 0.01) had significantly lower odds of HR + /HER2- breast cancer compared to category 0. The highest intensity category of metformin had 39% lower odds of HR + /HER2- breast cancer (OR = 0.61, 95% CI 0.46-0.82,p < 0.01) compared to the 0 mg/day group.

CONCLUSIONS

Higher metformin exposure was associated with reduced risk of HR + /HER2- breast cancer, adding to the evidence supporting metformin's chemoprotective effect.

Postmenopausal Hormone Therapy and Its Association with Breast Cancer

With the cessation of estrogen and progesterone at menopause, the hormone withdrawal affects various systems in the woman's body. In earlier days, menopausal hormone therapy (HT) was prescribed for primary prevention of coronary artery disease (CAD) and osteoporosis, which were thought to be because of estrogen deprivation and epidemiologic data supported a beneficial effect of estrogen on the heart and bone. Later on, robust data from the Women's Health Initiative study comparing two HT trials demonstrated adverse outcomes in terms of excess risk of CAD, stroke, venous thromboembolism, and breast cancer. Even with risk stratification based on family history, approximately only 15% of women diagnosed with breast cancer have such a risk factor. This implies that family history will not be elicited in more than 85% of women who develop breast cancer. Literature review suggests that the prior use of conjugated equine estrogen (CEE) alone has the potential to be effective as an intervention, leading to a reduction in mortality due to breast cancer. Therefore, it is time to reevaluate the risk reduction strategies for breast cancer that are currently in practice. In terms of absolute numbers, for every 10,000 person-years of prior use of CEE alone, there would be only two fewer deaths from breast cancer and two fewer deaths secondary to its sequelae. This translates into a significant number of women in our country with a population of 1.38 billion (of which 48%, nearly 650 million, are women).

Hormone Replacement Therapy, Breast Cancer Risk Factors, and Breast Cancer Risk: A Nationwide Population-Based Cohort

BACKGROUND

Hormone replacement therapy (HRT) increases the risk of breast cancer, but the association may vary according to patient factors. We investigated the association between HRT and breast cancer in a nationwide cohort with risk stratification according to risk factors for breast cancer.

METHODS

Using the Korean National Health Insurance Service database, 4,558,376 postmenopausal women who underwent breast cancer screening and regular health checkups from 2009 to 2014 were analyzed.

RESULTS

A total of 696,084 (15.3%) women reported current or previous HRT use. Breast cancer was newly diagnosed in 26,797 (0.6%) women during a median follow-up of 5.35 years. The HR of the risk of breast cancer in HRT users was 1.25 [95% confidence interval (CI), 1.22-1.29] compared with HRT nonusers. The risk of breast cancer increased according to HRT duration [adjusted HR = 1.08; 95% CI, 1.04-1.12, for <2 years; adjusted HR = 1.33; 95% CI, 1.25-1.40, for 2 to <5 years; and adjusted HR = 1.72; 95% CI, 1.63-1.82, for ≥5 years). The effects of HRT on breast cancer risk applied to both invasive and in situ cancer. The HRT-related risk of breast cancer was higher in women who were leaner and those who had dense breasts.

CONCLUSIONS

This nationwide population-based study confirms the association between HRT use and breast cancer risk. The risk increased proportionally with duration of HRT and differed according to body weight and breast density.

IMPACTS

Risk stratification would be useful when deciding whether to apply HRT for relief of menopausal symptoms.

Risk factors for Luminal A ductal carcinoma in situ (DCIS) and invasive breast cancer in the Carolina Breast Cancer Study

Purpose

Invasive breast cancers are thought to arise from in situ lesions, but some ductal carcinoma in situ (DCIS) are indolent with low likelihood of progressing to invasive carcinoma. Comparison of risk factor associations between DCIS and invasive disease may elucidate which factors influence early versus late stages of carcinogenesis. Therefore, we determined whether there were differences in risk factor profiles for screen-detected DCIS and invasive breast cancer among Luminal A lesions.

Methods

We conducted a case-control analysis using data from the Carolina Breast Cancer Study (1993–2001). Analyses were restricted to Luminal A tumors and screen-detected tumors among mammography-eligible women, to limit confounding by mode of detection (N = 108 DCIS; N = 203 invasive). Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for associations between risk factors and lesion type.

Results

In stratified analyses, we observed qualitative differences in the direction of association for ever smoking, obese BMI, high waist-to-hip-ratio (WHR), and ≥10 years of oral contraceptive use between DCIS and invasive disease. Breastfeeding was inversely associated with invasive disease and was not associated with DCIS. Interaction tests for risk factor associations between Luminal A DCIS and invasive breast cancer were not statistically significant (p>0.05).

Conclusions

Among Luminal A tumors, established breast cancer risk factors may exert stronger effects on progression of early lesions to invasive disease, with lesser effects on risk of DCIS.

The mammography screening detection of ductal carcinoma in situ and invasive breast cancer according to women's characteristics: is it the same?

PURPOSE

Detection of ductal carcinoma in situ (DCIS) has increased with the mammography dissemination. Given the potential role of DCIS as a precursor of invasive breast cancer (IBC), we aimed to assess whether women's characteristics have a different effect on the DCIS compared to IBC detection rate.

METHODS

This study included 3,609,569 screening mammograms performed from 2002 to 2015 in our organized breast cancer screening program, which actively invites women 50-69 years of age. The association between women's characteristics and the DCIS detection rate, the IBC detection rate and the odds ratio of DCIS among screen-detected cancers was assessed by logistic regression and generalized estimating equations with independent correlation matrix and sandwich estimator.

RESULTS

A total of 4173 DCIS and 15,136 IBC were screen-detected. Increasing women's age, current hormone replacement therapy use and higher body mass index were less associated with the DCIS than with IBC detection rates (p value for the odds of DCIS among screen-detected cancers of, respectively, < 0.0001, 0.0244 and < 0.0001). In contrast, having a previous breast aspiration or biopsy and increasing breast density were more strongly associated with DCIS than with IBC detection rates (p value of, respectively, 0.0050 and < 0.0001).

CONCLUSION

The results suggest that some women's characteristics could be playing a role in the initiation and other in the progression from in situ to invasive breast cancer. These characteristics can also affect the screening sensitivity, and this effect may differ depending on whether screen-detected cases were DCIS or IBC.

E-cadherin breast tumor expression, risk factors and survival: Pooled analysis of 5,933 cases from 12 studies in the Breast Cancer Association Consortium

E-cadherin (CDH1) is a putative tumor suppressor gene implicated in breast carcinogenesis. Yet, whether risk factors or survival differ by E-cadherin tumor expression is unclear. We evaluated E-cadherin tumor immunohistochemistry expression using tissue microarrays of 5,933 female invasive breast cancers from 12 studies from the Breast Cancer Consortium. H-scores were calculated and case-case odds ratios (OR) and 95% confidence intervals (CIs) were estimated using logistic regression. Survival analyses were performed using Cox regression models. All analyses were stratified by estrogen receptor (ER) status and histologic subtype. E-cadherin low cases (N = 1191, 20%) were more frequently of lobular histology, low grade, >2 cm, and HER2-negative. Loss of E-cadherin expression (score < 100) was associated with menopausal hormone use among ER-positive tumors (ever compared to never users, OR = 1.24, 95% CI = 0.97-1.59), which was stronger when we evaluated complete loss of E-cadherin (i.e. H-score = 0), OR = 1.57, 95% CI = 1.06-2.33. Breast cancer specific mortality was unrelated to E-cadherin expression in multivariable models. E-cadherin low expression is associated with lobular histology, tumor characteristics and menopausal hormone use, with no evidence of an association with breast cancer specific survival. These data support loss of E-cadherin expression as an important marker of tumor subtypes.

Change in risk of breast cancer after receiving hormone replacement therapy by considering effect-modifiers: a systematic review and dose-response meta-analysis of prospective studies

We synthesize the current literatures and use the power of meta-analysis to examine trends on association between hormone replacement therapy (HRT) and the risk of breast cancer (BC). We performed a comprehensive literature search using PubMed, EMBASE, and Web of Science from their inception until Jan 2017. Prospective studies that provided adjusted risk estimates of HRT and BC risk were eligible. Categorical and dose-response meta-analyses followed the PRISMA were conducted using random effects model and restricted cubic spline model, respectively. Forty-seven publications from thirty-five unique studies were included, involving 3,898,376 of participants and 87,845 of BC cases. Compared with non-users, RR for current estrogen-only therapy (ET) users was 1.14 (95% confidence interval (CI) = 1.05–1.22), and for per year increases was 1.02 (95% CI = 1.02–1.02). Moreover, RR for current estrogen plus progestin therapy (EPT) users was 1.76, (95% CI = 1.56–1.96), and for per year increases was 1.08 (95% CI = 1.08–1.08). Dose-response analyses revealed 8–10 years’ onset peaks, and indicated residual increased BC risk remained after stopping use of ET regimen rather than for EPT. Effect-modifiers like BMI, duration of use, race/ethnicity, routes of administration were recognized. In Conclusions, current use of EP or EPT and ever use of tibolone are associated with an elevated risk of BC. Compared with slim HRT users and non-users, lower BC risks were found among overweight/obese HRT users and former EPT users, respectively. Both ET and EPT users are associated with higher risk of lobular BC than ductal BC, and more ER-positive than negative BC cases were detected among EPT users.

Therapeutic Role of Punica Granatum (Pomegranate) Seed Oil Extract on Bone Turnover and Resorption Induced in Ovariectomized Rats

CONTEXT

Postmenopausal osteoporosis is mostly caused by increased bone remodeling resulting from estrogen deficiency. Hormone replacement therapy (HRT) is used to prevent osteoporosis, but it increases the risk for breast cancer, thromboembolism, strokes, and heart attacks. Pomegranate seed oil extract (SOE) is rich in phytoestrogen and antioxidant compounds.

OBJECTIVES

To evaluate the therapeutic role of SOE against bone turnover, resorption and osteoporosis induced in ovariectomized rats as a postmenopausal model and comparing the results with those from Generic CycloProgynova drug (D).

DESIGN

The study used western albino rats undergo bilaterally ovariectomization as a model for postmenopausal.

SETTING

The study took part in a laboratory setting.

ANIMALS

Forty female western albino rats (age: 3-4 months) weighing 150-180 gm.

MEASUREMENTS

Rats were divided into four groups, 10 rats each; SC-group: Sham control = untreated and unovariectomized rats; OVX-group = ovariectomized rats; (OVX-SOE) and (OVX-D) groups = OVX rats were treated with SOE and D, respectively. Bone markers (BMs) especially osteocalcin (BGP), alkaline phosphatase (ALP), tartarate resistance acid phosphatase (TRAcP), bone weight, bone calcium concentration, serum electrolytes (calcium, sodium and potassium) and serum estradiol (E2) level and histopathological examination of bones were determined. Also lipid profile, uric acid, prothrombin time (INR) and liver and kidney functions were measured to evaluate the adverse effects of SOE and D.

RESULTS

In OVX group the activities of ALP and TRAcP and the levels of BGP, serum calcium, sodium and body weight were significantly higher (p≤0.05) than SC-group, while bone calcium concentration, bone mass, serum E2 and potassium level as well as uterus mass were significantly lower (p≤0.05). Also histopathological results revealed that the outer cortical bone became thinner, while the cancellous bone trabeculae lost their normal architecture. Moreover in OVX group lipid profile and uric acid levels were significantly higher (p≤0.05) than SC group, but there were no significant changes (p≤0.05) in INR level, liver and kidney functions. Treatment of OVX rats with SOE or D for 12 weeks improved both the architecture of bones as shown from the histopathological results and BMs, serum electrolytes and E2 levels (p≤0.05) which approached SC-group. Moreover after treatment of OVX rats with SOE the levels of lipid profile and uric acid were improved and approached SC-group, while liver function became significant lower (p≤0.05) than SC-group. Also there were no significant changes (p≤0.05) in kidney functions and INR of (OVX-SOE), OVX and SC groups. In contrast in (OVX-D) group the levels of lipid profile, liver and kidney functions, uric acid and INR were significantly higher (p≤0.05) than those of OVX and SC groups.

CONCLUSION

The results of this study show that SOE has therapeutic effects on osteoporosis, while it has no adverse effects on lipid profile, uric acid, liver and kidney functions when compared to HRT. SOE offers a promising alternative in the design of new strategies in nutritional management of age-related bone complications.

Gender Differences in Depression

Depression is among the most prevalent and debilitating psychiatric disorders in the world. A striking feature of this disorder is that women are twice as likely to experience depression compared with men. Research indicates that genetic, biological and environmental factors contribute to the gender differences noted in depression. Women are more likely to suffer a greater number of and more severe stressful life events compared with men, although no gender difference has been found to explain the genetic vulnerability. As individuals with depression most frequently present to general practitioners, healthcare providers should consider screening for depression and using rigorous treatment strategies for depressed patients with comorbid medical illnesses.

Effects of estradiol and genistein on the insulin signaling pathway in the cerebral cortex of aged female rats

Menopause leads to a decrease in estrogen production that increases central insulin resistance, contributing to the development of neurodegenerative diseases. We have evaluated the influence of aging and estradiol or genistein treatments on some key stages of the insulin signaling pathway in the cerebral cortex. Young and aged female Wistar rats were ovariectomized and treated acutely with 17β-estradiol (1.4μg/kg body weight), two doses of genistein (10 or 40mg/kg body weight), or vehicle. The cortical expression of several key insulin signaling pathway components was analyzed by western blotting. Our results showed an age-related deterioration in the interactions between the regulatory subunit of phosphatidylinositol 3-kinase (p85α) and the activated form of insulin receptor substrate 1 (p-IRS1tyr612), as well as between p85α and the 46kDa isoform of the estrogen receptor α (ERα46). Moreover, aging also decreased the translocation of glucose transporter-4 (GLUT4) to the plasma membrane. 17β-Estradiol but not genistein reduced the negative impact of aging on central insulin sensitivity by favoring this GLUT4 translocation, and therefore could be neuroprotective against the associated neurodegenerative diseases. However, protein kinase B (Akt) activation by genistein suggests that other possible mechanisms are involved in the neuroprotective effects of this phytoestrogen during the aging process.

Interactions of hormone replacement therapy, body weight, and bilateral oophorectomy in breast cancer risk

PURPOSE

To examine potential modifying effects of body weight and bilateral oophorectomy on the association of hormone replacement therapy (HRT) with risk of breast cancer, overall and by subtypes according to status of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (Her2) among postmenopausal women.

EXPERIMENTAL DESIGN

This analysis included 2,510 postmenopausal white women recruited in the Nashville Breast Health Study, a population-based case-control study of breast cancer. Multivariable logistic regression was used to estimate ORs and 95% confidence intervals (CI) for associations between HRT use and risk of breast cancer overall and by subtypes, adjusted for age and education.

RESULTS

Among women with natural menopause and body mass index (BMI) < 25 kg/m(2), ever-use of HRT was associated with increased breast cancer risk (OR, 1.95; 95% CI, 1.32-2.88). Risk was elevated with duration of HRT use (P for trend = 0.002). Similar association patterns were found for ER(+), ER(+)PR(+), and luminal A cancer subtypes but not ER(-), ER(-)PR(-), and triple-negative cancer. In contrast, ever-HRT use in overweight women (BMI ≥ 25 kg/m(2)) showed no association with risk of breast cancer overall or by subtypes; interaction tests for modifying effect of BMI were statistically significant. Ever-HRT use was associated with decreased breast cancer risk (OR, 0.70; 95% CI, 0.38-1.31) among women with prior bilateral oophorectomy but elevated risk (OR, 1.45; 95% CI, 0.92-2.29) among those with hysterectomy without bilateral oophorectomy (P for interaction = 0.057). Similar associations were seen for virtually all breast cancer subtypes, although interaction tests were statistically significant for ER(+) and luminal A only.

CONCLUSION

Body weight and bilateral oophorectomy modify associations between HRT use and breast cancer risk, especially the risk of hormone receptor-positive tumors.

2-methoxyestradiol binding of GPR30 down-regulates angiotensin AT(1) receptor

Controlling angiotensin AT1 receptor function has been shown to be protective for many pathophysiological disorders. Although estrogen metabolite, 2-methoxyestradiol (2ME2) can down-regulate angiotensin AT1 receptor expression independently of nuclear receptors, no specific cellular targets have been identified. This study was focused on identification and validation of a cellular target responsible for 2ME2-mediated angiotensin AT1 receptor down-regulation in a continuously passaged rat liver epithelial cell line. Cell membranes were isolated and used to determine 2ME2 specific binding. Cell membranes exposed to [(3)H]2ME2 showed specific saturable binding, which was found to be pertussis toxin (PTx) sensitive. Under similar conditions, G-protein coupled receptor 30 (GPR30) agonist (G1) and antagonist (G15) inhibited 2ME2 specific binding. In these cells GPR30 was found localized to endoplasmic reticulum (ER) membranes. In intact cells, G1 down-regulated angiotensin AT1 receptor expression and this effect was reversed by G15. Furthermore, 2ME2 mediated activation of epidermal growth factor receptor (EGFR) followed by ERK1/2 phosphorylation, an essential signaling step in angiotensin AT1 receptor down-regulation, was abrogated by G15, suggesting that this signal is GPR30 dependent. Additionally, EGF was found to independently down-regulate angiotensin AT1 receptor in an ERK1/2-dependent manner. In summary, our results demonstrate for the first time that 2ME2 down-regulation of angiotensin AT1 receptor is dependent on ER membrane-associated GRP30. Moreover, this effect is facilitated by GPR30 dependent transactivation of EGFR and ERK1/2 phosphorylation. This study provides further understanding of the physiological significance of 2ME2 and its role in modulating angiotensin AT1 receptor expression.

Bone mass density estimation: Archimede's principle versus automatic X-ray histogram and edge detection technique in ovariectomized rats treated with germinated brown rice bioactives

Background

Bone mass density is an important parameter used in the estimation of the severity and depth of lesions in osteoporosis. Estimation of bone density using existing methods in experimental models has its advantages as well as drawbacks.

Materials and methods

In this study, the X-ray histogram edge detection technique was used to estimate the bone mass density in ovariectomized rats treated orally with germinated brown rice (GBR) bioactives, and the results were compared with estimated results obtained using Archimede’s principle. New bone cell proliferation was assessed by histology and immunohistochemical reaction using polyclonal nuclear antigen. Additionally, serum alkaline phosphatase activity, serum and bone calcium and zinc concentrations were detected using a chemistry analyzer and atomic absorption spectroscopy. Rats were divided into groups of six as follows: sham (nonovariectomized, nontreated); ovariectomized, nontreated; and ovariectomized and treated with estrogen, or Remifemin®, GBR-phenolics, acylated steryl glucosides, gamma oryzanol, and gamma amino-butyric acid extracted from GBR at different doses.

Results

Our results indicate a significant increase in alkaline phosphatase activity, serum and bone calcium, and zinc and ash content in the treated groups compared with the ovariectomized nontreated group (P < 0.05). Bone density increased significantly (P < 0.05) in groups treated with estrogen, GBR, Remifemin®, and gamma oryzanol compared to the ovariectomized nontreated group. Histological sections revealed more osteoblasts in the treated groups when compared with the untreated groups. A polyclonal nuclear antigen reaction showing proliferating new cells was observed in groups treated with estrogen, Remifemin®, GBR, acylated steryl glucosides, and gamma oryzanol. There was a good correlation between bone mass densities estimated using Archimede’s principle and the edge detection technique between the treated groups (r² = 0.737, P = 0.004).

Conclusion

Our study shows that GBR bioactives increase bone density, which might be via the activation of zinc formation and increased calcium content, and that X-ray edge detection technique is effective in the measurement of bone density and can be employed effectively in this respect.

Ductal Carcinoma In Situ of the Breast

Ductal carcinoma in situ (DCIS) of the breast is a potentially invasive neoplasm. Risk factors include high estrogen states such as use of oral contraceptive (OC) pills, nulliparity, advanced age at first birth, and also family history and genetic mutations. The incidence of this usually clinically silent condition has risen in the past few decades due to widespread screening and diagnostic mammography, with final diagnosis confirmed by biopsy. At present, treatment options include total or simple mastectomy or lumpectomy with radiation. Adjuvant therapy includes antiestrogens like tamoxifen and human epidermal growth factor receptor 2 (HER2) suppression therapy. With the latest advances in chemotherapy and better understanding on the pathogenesis of the lesion, it is anticipated that more effective modalities of treatment may soon be available.

Reproductive, lifestyle, and anthropometric risk factors for cancer in elderly women

BACKGROUND

With an increasing elderly population, the United States will experience an increased cancer burden in the coming years. We evaluated associations between anthropometric, lifestyle, and reproductive factors and risk of breast, ovarian, and colorectal cancer in a prospective study of postmenopausal women with a focus on diagnoses occurring among very elderly women (≥75 years).

METHODS

For each cancer type, we estimated associations with relevant exposures in 2 age bands (<75 vs. ≥75 years of age). During 22 years of follow-up, 322 ovarian, 1,311 colon, 315 rectal, and 2,664 breast cancers occurred among 37,459 postmenopausal women (mean age at baseline 62 years, range 55-71 years).

RESULTS

For ovarian cancer, we identified few significant associations in either age band. Colon cancer cases had a higher body mass index and were less likely to report estrogen or aspirin use than non-cases, yet these associations were consistent in both age bands. Few risk factors were identified for rectal cancer in women of 75 years of age or more. For breast cancer, notably different patterns were revealed, with alcohol consumption associated with risk in the younger group and previous hysterectomy associated with risk only in the older group.

CONCLUSION

These analyses suggest some important differences in risk factors for cancer depending on the age at diagnosis.

IMPACT

This study suggests that etiologic differences may exist in cancers occurring in the very elderly women. The ongoing demographic shift in the United States provides a strong rationale for studies evaluating cancer etiology in the elderly.

17β-Estradiol and genistein acute treatments improve some cerebral cortex homeostasis aspects deteriorated by aging in female rats

Aging is associated with decreased insulin sensitivity and impaired cerebral glucose homeostasis. These changes increase neural sensitivity to metabolic damage contributing to cognitive decline, being the decrease in plasma estrogen following menopause one of the main factors involved in aged females. Phytoestrogens as genistein are structurally similar to 17β-estradiol, bind to estrogen receptors, and can evoke both estrogenic and anti-estrogenic effects. Estrogens and phytoestrogens have neuroprotective potential, but the physiological mechanisms are not fully understood. Young and aged female Wistar rats were ovariectomized and treated acutely with 17β-estradiol (1.4μg/kg body weight), genistein (10 or 40 mg/kg body weight), or vehicle. Cortical expression of glucose transporter-3 (GLUT-3) and -4 (GLUT-4), cytochrome c oxidase (CO), estrogen receptor-α (ERα) and -β (ERβ) was measured by Western blotting. There was an age-related decline in GLUT-4, CO and ERβ levels. Both drugs, estradiol and genistein, were able to reverse GLUT-3 downregulation in the cortex following late ovariectomy. However, genistein was the only treatment able to restore completely GLUT-4 levels in aged rats. In contrast, estradiol was more potent than genistein at increasing CO, a marker of cerebral oxidative metabolism. As regards ER levels, estradiol increased the ERα67 quantity diminished by late ovariectomy, while genistein did the same with the other ERα isoform, ERα46, highlighting drug-specific differences in expression changes for both isoforms. On the other hand, no treatment-related differences were found regarding ERβ levels. Therefore, genistein like estradiol could be suitable treatments against cortical metabolic dysfunction caused by aging. These treatments may hold promise as neuroprotective strategies against diabetes and age-related neurodegenerative diseases.

Effects of menopausal hormone therapy on ductal carcinoma in situ of the breast

Post-menopausal hormone therapy with estrogen plus progestin is consistently reported to be associated with an increased risk of invasive breast cancer. However, findings on an association between hormone use and ductal carcinoma in situ of the breast (DCIS), a possible precursor lesion of invasive breast cancer, are sparse and inconsistent. Women's Health Initiative data were used to assess the effects of hormone therapy on the risk of DCIS in two clinical trials of hormone therapy (16,276 women enrolled in the trial of daily conjugated equine estrogens plus medroxyprogesterone acetate (CEE + MPA) vs placebo; 10,187 women enrolled in the trial of CEE-alone vs placebo). The effects of hormone therapy on DCIS in clinical trial participants were assessed during the intervention, post-intervention, and entire followup periods, and in the observational study (OS; 30,421 CEE + MPA users and non-users and 18,657 CEE-alone users and non-users who met eligibility criteria similar to the clinical trial). Compared to placebo, CEE + MPA was non-significantly associated with higher risk of DCIS over approximate average of 11 years of follow-up (HR = 1.23; 95 % CI: 0.91-1.64). No statistical difference was detected between intervention and post-intervention phases (p = 0.32). Corresponding OS results supported an increased risk for DCIS in CEE + MPA users compared to women who were non-users (HR = 1.65; 95 % CI: 1.25-2.19) after adjusting for potential confounders. There was no clear association between CEE-alone use and risk of DCIS. CEE-alone trial data showed that the risk of DCIS was non-significantly lower in the treatment than in the placebo group, while analysis of the corresponding OS showed a non-significantly higher risk of DCIS in the CEE-alone users than non-users. Our analysis suggests that combined estrogen plus progestin use in post-menopausal women may increase risk of DCIS. Whether estrogen-alone use is associated with DCIS requires further investigation.

A comparison of the polytomous logistic regression and joint cox proportional hazards models for evaluating multiple disease subtypes in prospective cohort studies

BACKGROUND

Polytomous logistic regression models are commonly used in case-control studies of cancer to directly compare the risks associated with an exposure variable across multiple cancer subtypes. However, the validity, accuracy, and efficiency of this approach for prospective cohort studies have not been formally evaluated.

METHODS

We investigated the performance of the polytomous logistic regression model and compared it with an alternative approach based on a joint Cox proportional hazards model using simulation studies. We then applied both methods to a prospective cohort study to assess whether the association of breast cancer with body size differs according to estrogen and progesterone receptor-defined subtypes.

RESULTS

Our simulations showed that the polytomous logistic regression model but not the joint Cox regression model yielded biased results in comparing exposure and disease subtype associations when the baseline hazards for different disease subtypes are nonproportional. For this reason, an analysis of a real data set was based on the joint Cox proportional hazards model and showed that body size has a significantly greater association with estrogen- and progesterone-positive breast cancer than with other subtypes.

CONCLUSIONS

Because of the limitations of the polytomous logistic regression model for the comparison of exposure-disease associations across disease subtypes, the joint Cox proportional hazards model is recommended over the polytomous logistic regression model in prospective cohort studies.

IMPACT

The article will promote the use of the joint Cox model in a prospective cohort study. Examples of SAS and S-plus programming codes are provided to facilitate use by nonstatisticians.

Ductal carcinoma in situ of the breast: a surgical perspective

Ductal carcinoma in situ (DCIS) of the breast is a heterogeneous neoplasm with invasive potential. Risk factors include age, family history, hormone replacement therapy, genetic mutation, and patient lifestyle. The incidence of DCIS has increased due to more widespread use of screening and diagnostic mammography; almost 80% of cases are diagnosed with imaging with final diagnosis established by biopsy and histological examination. There are various classification systems used for DCIS, the most recent of which is based on the presence of intraepithelial neoplasia of the ductal epithelium (DIN). A number of molecular assays are now available that can identify high-risk patients as well as help establish the prognosis of patients with diagnosed DCIS. Current surgical treatment options include total mastectomy, simple lumpectomy in very low-risk patients, and lumpectomy with radiation. Adjuvant therapy is tailored based on the molecular profile of the neoplasm and can include aromatase inhibitors, anti-estrogen, anti-progesterone (or a combination of antiestrogen and antiprogesterone), and HER2 neu suppression therapy. Chemopreventive therapies are under investigation for DCIS, as are various molecular-targeted drugs. It is anticipated that new biologic agents, when combined with hormonal agents such as SERMs and aromatase inhibitors, may one day prevent all forms of breast cancer.

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.

Postmenopausal hormone therapy and ductal carcinoma in situ: a population-based case-control study

BACKGROUND AND AIM

The relationship between hormone therapy (HT) and invasive breast cancer has been extensively investigated, but the relationship between HT and in situ breast cancer has received relatively little attention. We examined the relationship between HT and ductal carcinoma in situ (DCIS) among postmenopausal women who participated in a population-based case-control study in Connecticut, USA.

METHODS

This analysis included 1179 post-menopausal women (603 controls and 576 cases), who comprised a subset of a population-based case-control study that included all incident cases of breast carcinoma in situ (BCIS) in Connecticut and frequency-matched controls by 5-year age intervals.

RESULTS

We found no association between DCIS and ever use of any HT (adjusted odds ratio (OR)=0.85, 95% confidence interval (CI): 0.65-1.11); of estrogen alone (adjusted OR=0.93; 95% CI: 0.68-1.29) or of estrogen and progesterone (adjusted OR=0.75; 95% CI: 0.52-1.08). There was also no association between DCIS and current use of these hormones. In addition, estimated risk of DCIS did not increase with duration of use of these preparations.

CONCLUSIONS

These results add to a small literature that remains inconclusive. To determine whether HT poses risk of in situ breast cancer, larger studies with greater power and precise control of important covariates (e.g., mammography screening) are needed, as are meta-analyses of available data.

Understanding recent trends in incidence of invasive breast cancer in Norway: age-period-cohort analysis based on registry data on mammography screening and hormone treatment use

OBJECTIVE

To quantify the separate contributions of menopausal hormone treatment and mammography screening activities on trends in incidence of invasive breast cancer between 1987 and 2008.

DESIGN

Population study using aggregated data analysed by an extended age-period-cohort model.

SETTING

Norway. Population Norwegian women aged 30-90 between 1987 and 2008, including 50,102 newly diagnosed cases of invasive breast cancer. Main outcomes measures Attributable proportions of mammography screening and hormone treatment to recent incidence of invasive breast cancer, and the remaining variation in incidence after adjustment for mammography screening and hormone treatment.

RESULTS

The incidence of invasive breast cancer in Norway increased steadily until 2002, levelled off, and then declined from 2006. All non-linear changes in incidence were explained by use of hormone treatment and mammography screening activities, with about similar contributions of each factor. In 2002, when the incidence among women aged 50-69 was highest, an estimated 23% of the cases in that age group could be attributed to mammography screening and 27% to use of hormone treatment.

CONCLUSIONS

Changes in incidence trends of invasive breast cancer since the early 1990s may be fully attributed to mammography screening and hormone treatment, with about similar contributions of each factor.

Menopausal hormone therapy: what we know now

OVERVIEW

This article describes the findings and limitations of the major research thus far on hormone therapy, particularly that of the Women's Health Initiative; examines practice recommendations; clarifies common terminology related to menopause and hormone therapy; and provides the implications for nurses. This is part one of a four-part series on postmenopausal health.

KEYWORDS

bioidentical hormones, combined estrogen and progestogen therapy, estrogen, estrogen therapy, hormone therapy, menopause, menopausal transition, postmenopause, progestin, progestogen, women's health, Women's Health Initiative.

Ductal carcinoma in situ: risk factors and impact of screening

BACKGROUND

The National Institutes of Health Office of Medical Applications of Research commissioned a structured literature review on the incidence of ductal carcinoma in situ (DCIS) as a background paper for the State of the Science Conference on Diagnosis and Management of DCIS.

METHODS

Published studies were abstracted from MEDLINE and other sources. We include articles published through January 31, 2009; 92 publications were abstracted.

RESULTS

DCIS incidence rose from 1.87 per 100,000 in 1973-1975 to 32.5 per 100,000 in 2005. Increases in incidence were greatest in tumors without comedo necrosis. Incidence increased in all ages but more in women older than 50 years. Increased use of mammography explains some but not all of the increased incidence. Risk factors for incident DCIS include older age and positive family history. Whereas tamoxifen prevents both invasive breast cancer and DCIS, raloxifene is associated with decreased invasive breast cancer but not decreased DCIS.

CONCLUSIONS

Scientific questions deserving further investigation include the relationship between mammography use and DCIS incidence and the role of chemoprevention for reducing the incidence of DCIS and invasive breast cancer.

Age-related variation in the relationship between menopausal hormone therapy and the risk of dying from breast cancer

Multiple past studies have reported a reduced risk of breast cancer-related mortality (BCM) in relation to pre-diagnostic use of hormone therapy (HT); however, the extent to which this reduction is due to heightened screening or tumor biology is unknown. Using a population-based cohort of 1,911 post-menopausal women diagnosed with invasive breast cancer at ages 45-79 from 1993 to 1999, we investigated the extent to which the reduced risk in BCM observed in relation to HT might be explained by screening patterns or tumor features. Estrogen-progestin therapy (EPT) use was associated with a decreased risk of BCM (after adjustment for age, study, mammography, stage, and treatment), but only among older women (ever use: ≥ 65 years: HR = 0.45 [95% CI 0.26-0.80]; <65 years: HR = 1.03 [95% CI 0.60-1.79]). Estrogen-alone therapy (ET) use was not associated with risk of BCM (ever use: ≥ 65 years: HR = 0.76 [95% CI 0.51-1.12]; <65 years: HR = 1.20 [95% CI 0.71-2.02]). HT users had a much greater frequency of mammography (P value <0.001). EPT use was associated with tumor characteristics related to improved prognosis in older women after adjustment for screening, including an inverse association with poorly differentiated tumors (OR = 0.57 [95% CI 0.38-0.85]) and an association with lobular tumors (OR = 1.68 [95% CI 1.07-2.65]). Beyond the influence of EPT use on screening uptake, these data indicate that the improved survival associated with pre-diagnostic EPT use may be due in part to the development of more favorable tumor characteristics.

Cigarette smoking in relation to risk of ductal carcinoma in situ of the breast in a cohort of postmenopausal women

In numerous studies, investigators have examined the association of active smoking with risk of invasive breast cancer, but to the authors' knowledge, no cohort study has assessed smoking in relation to the risk of in situ breast cancer, the postulated penultimate stage preceding invasive breast cancer. The authors examined the latter association using data collected at baseline from 63,393 women in the Women's Health Initiative Clinical Trial. A total of 486 cases of ductal carcinoma in situ (DCIS) of the breast were identified during 8 years of follow-up between 1993 and 2005. Cox proportional hazards models were used to estimate hazard ratios and 95% confidence intervals. For the primary analysis, invasive breast cancer was treated as a competing risk. After adjustment for covariates, associations with smoking status, smoking intensity, duration, pack-years, and age at quitting were all close to the null value and showed few meaningful trends. Sensitivity analyses performed to address different possibilities with respect to the natural history of breast cancer also did not provide consistent evidence of an association of smoking with DCIS. The results of this large cohort study provide little support for an association of cigarette smoking with risk of DCIS in postmenopausal women.

Pregnancy-related factors and the risk of breast carcinoma in situ and invasive breast cancer among postmenopausal women in the California Teachers Study cohort

Introduction

Although pregnancy-related factors such as nulliparity and late age at first full-term pregnancy are well-established risk factors for invasive breast cancer, the roles of these factors in the natural history of breast cancer development remain unclear.

Methods

Among 52,464 postmenopausal women participating in the California Teachers Study (CTS), 624 were diagnosed with breast carcinoma in situ (CIS) and 2,828 with invasive breast cancer between 1995 and 2007. Multivariable Cox proportional hazards regression methods were used to estimate relative risks associated with parity, age at first full-term pregnancy, breastfeeding, nausea or vomiting during pregnancy, and preeclampsia.

Results

Compared with never-pregnant women, an increasing number of full-term pregnancies was associated with greater risk reduction for both breast CIS and invasive breast cancer (both P trend < 0.01). Women having four or more full-term pregnancies had a 31% lower breast CIS risk (RR = 0.69, 95% CI = 0.51 to 0.93) and 18% lower invasive breast cancer risk (RR = 0.82, 95% CI = 0.72 to 0.94). Parous women whose first full-term pregnancy occurred at age 35 years or later had a 118% greater risk for breast CIS (RR = 2.18, 95% CI = 1.36 to 3.49) and 27% greater risk for invasive breast cancer (RR = 1.27, 95% CI = 0.99 to 1.65) than those whose first full-term pregnancy occurred before age 21 years. Furthermore, parity was negatively associated with the risk of estrogen receptor-positive (ER+) or ER+/progesterone receptor-positive (PR+) while age at first full-term pregnancy was positively associated with the risk of ER+ or ER+/PR+ invasive breast cancer. Neither of these factors was statistically significantly associated with the risk of ER-negative (ER-) or ER-/PR- invasive breast cancer, tests for heterogeneity between subtypes did not reach statistical significance. No clear associations were detected for other pregnancy-related factors.

Conclusions

These results provide some epidemiologic evidence that parity and age at first full-term pregnancy are involved in the development of breast cancer among postmenopausal women. The role of these factors in risk of in situ versus invasive, and hormone receptor-positive versus -negative breast cancer merits further exploration.

Ductal carcinoma in situ of the breast: a systematic review of incidence, treatment, and outcomes

BACKGROUND

The National Institutes of Health Office of Medical Applications of Research commissioned a structured literature review on the incidence, treatment, and outcomes of ductal carcinoma in situ (DCIS) as a background article for the State of the Science Conference on Diagnosis and Management of DCIS.

METHODS

Published studies were identified and abstracted from MEDLINE and other sources. We include articles published between 1965 and January 31, 2009; 374 publications were identified that addressed DCIS incidence, staging, treatment, and outcomes in adult women.

RESULTS

In the United States, DCIS incidence rose from 1.87 per 100 000 in 1973-1975 to 32.5 in 2004. Incidence increased in all ages but more so in women older than 50 years. Increased use of mammography explains some but not all of the increased incidence. Risk factors for incident DCIS include older age and family history. Although tamoxifen treatment prevented both invasive breast cancer and DCIS, raloxifene treatment decreased incidence of invasive breast cancer but not DCIS. Among patients with DCIS, magnetic resonance imaging was more sensitive than mammography for detecting multicentric disease and estimating tumor size. Because about 15% of patients with DCIS identified on core needle biopsy are diagnosed with invasive breast cancer after excision or mastectomy, the accuracy of sentinel lymph node biopsy after excision is relevant to surgical management of DCIS. Most studies demonstrated that sentinel lymph node biopsy is feasible after breast-conserving surgery (BCS). Younger age, positive surgical margins, tumor size and grade, and comedo necrosis were consistently related to DCIS recurrence. DCIS outcomes after either mastectomy or BCS plus radiation therapy were superior to BCS alone. Tamoxifen treatment after DCIS diagnosis reduced risk of recurrent disease.

CONCLUSIONS

Scientific questions deserving further investigation include the relationship between mammography use and DCIS incidence and whether imaging technologies and treatment guidelines can be modified to focus on lesions that are most likely to become clinically problematic.

Hormone Replacement Therapy: A Critical Review

The aim of this chapter is to review the most recent aspects of hormone replacement therapy (HRT), and to clarify its impact on associated health conditions amidst growing uncertainties. Special emphasis has been placed on its effect on cardiovascular conditions and breast cancer, the two most important outcomes affected by HRT, and on identifying ideal candidates for HRT as well as defining the optimum new HRT regimens.

Hormone replacement therapy (HRT), breast cancer and tumor pathology

Within an average observation period of 5-6 years, several clinical trials reported an increased risk of breast cancer due to hormone replacement therapy (HRT). However, it remains disputable, whether the increased rate of breast cancers detected within the given time frame is indeed due to newly induced tumors and thus constitutes HRT-initiated primary breast cancers. Onco-pathologically speaking it appears more likely that HRT stimulates the growth of already existing small tumor nests which - due to their small size - would otherwise go undiagnosed. The major arguments are: In summary, HRT is hence more likely to be a tumor promoter than a de novo-inducer of breast cancers.

Progress in osteoporosis and fracture prevention: focus on postmenopausal women

In the past decade, we have witnessed a revolution in osteoporosis diagnosis and therapeutics. This includes enhanced understanding of basic bone biology, recognizing the severe consequences of fractures in terms of morbidity and short-term re-fracture and mortality risk and case finding based on clinical risks, bone mineral density, new imaging approaches, and contributors to secondary osteoporosis. Medical interventions that reduce fracture risk include sufficient calcium and vitamin D together with a wide spectrum of drug therapies (with antiresorptive, anabolic, or mixed effects). Emerging therapeutic options that target molecules of bone metabolism indicate that the next decade should offer even greater promise for further improving our diagnostic and treatment approaches.

Hormone therapy and breast cancer risk

Hormone therapy (HT) is the most efficacious intervention for the relief of climacteric symptoms. Controversies surrounding HT have left many women puzzled and afraid. Gynecologists are faced with long-standing beneficial assumptions challenged by an abundance of robust detrimental new data, with little guidance on how to interpret these findings. Prescriptions for HT (and incidence of breast cancers in some areas) have fallen over the last 3 years due to anxiety provoked about breast cancer risk and recurrence. The current 'clinical climate' is against HT. Due to a lack of effective alternatives, women suffering from estrogen-deficiency symptoms are still requesting objective information about HT, particularly those at higher risk of breast cancer or those with a past history of breast cancer. In this situation, discussion of the current clinical uncertainty surrounding the use of HT must be undertaken to ensure that women are adequately informed. The objective of this presentation is to provide a framework for understanding breast cancer risk associated with HT. What are the precise molecular mechanisms of estrogen and progestin in the initiation of breast cancer? Does the risk of estrogen-only therapy on breast cancer vary by dose, constituent, route and duration of administration and cessation of use? Does HT, in addition to increasing risk for breast cancer, affect the type of breast cancer (lobular and ductal) diagnosed? Is HT associated with breast cancers that have better prognostic factors? How relevant are the changes in mammographic breast density associated with HT for the evaluation of breast cancer risk? What is the additional global health risk/benefit ratio associated with the selective use of progesterone or progestin that may confer a significant cardiovascular benefit, such as drospirenone? It is currently assumed and tested that new hormones with particular pharmacological profiles may ultimately achieve their therapeutic goal of relieving climacteric symptoms without an associated moderate increased risk of breast cancer.

Recent trends in breast cancer incidence in US white women by county-level urban/rural and poverty status

BACKGROUND

Unprecedented declines in invasive breast cancer rates occurred in the United States between 2001 and 2004, particularly for estrogen receptor-positive tumors among non-Hispanic white women over 50 years. To understand the broader public health import of these reductions among previously unstudied populations, we utilized the largest available US cancer registry resource to describe age-adjusted invasive and in situ breast cancer incidence trends for non-Hispanic white women aged 50 to 74 years overall and by county-level rural/urban and poverty status.

METHODS

We obtained invasive and in situ breast cancer incidence data for the years 1997 to 2004 from 29 population-based cancer registries participating in the North American Association of Central Cancer Registries resource. Annual age-adjusted rates were examined overall and by rural/urban and poverty of patients' counties of residence at diagnosis. Joinpoint regression was used to assess trends by annual quarter of diagnosis.

RESULTS

Between 2001 and 2004, overall invasive breast cancer incidence fell 13.2%, with greater reductions among women living in urban (-13.8%) versus rural (-7.5%) and low- (-13.0%) or middle- (-13.8%) versus high- (-9.6%) poverty counties. Most incidence rates peaked around 1999 then declined after second quarter 2002, although in rural counties, rates decreased monotonically after 1999. Similar but more attenuated patterns were seen for in situ cancers.

CONCLUSION

Breast cancer rates fell more substantially in urban and low-poverty, affluent counties than in rural or high-poverty counties. These patterns likely reflect a major influence of reductions in hormone therapy use after July 2002 but cannot exclude possible effects due to screening patterns, particularly among rural populations where hormone therapy use was probably less prevalent.

The influence of menopausal hormone therapy on tumour characteristics and survival in endometrial cancer patients

INTRODUCTION

Menopausal hormone therapy (MHT) is a well-established factor in endometrial carcinogenesis, and therefore, could have prognostic implications. We investigated the effects of ever use of MHT on tumour grade and depth of myometrial invasion and 5-year relative survival in postmenopausal endometrial cancer patients.

MATERIALS AND METHODS

We used a nationwide, population-based case-case design, of 683 Swedish women aged 50-74 years diagnosed with endometrial cancer during 1994 to 1995, followed up to 5 years after diagnosis. We applied polytomous multiple logistic regression to investigate the associations between the use of MHT and tumour grade, and myometrial invasion and Poisson regression for modelling 5-year excess mortality.

RESULTS

Compared to never use, ever use of any MHT entailed lower risks of having moderately and poorly differentiated tumours. The lowest odds ratios for poorly differentiated tumours were seen for ever users of cyclically combined oestrogen-progestin [OR=0.23 (95% CI=0.07-0.73)]. Ever users of any form of MHT; particularly, medium potency MHT users, had significantly lower risks for tumours with deep myometrial invasion. Adjusted estimated relative excess hazard ratios revealed significantly improved survival for ever users of any form of MHT [RER=0.40 (95% CI=0.16-0.97)]; in particular ever users of any form of oestrogens [RER=0.38 (95% CI=0.15-0.99)].

CONCLUSION

Endometrial cancer patients who were ever users of MHT had more favourable tumour characteristics and better survival compared to never users of MHT. These findings support the notion that MHT induces endometrial cancer with less aggressive characteristics.

Reproductive and hormonal risk factors for ductal carcinoma in situ of the breast

One-fifth of all newly diagnosed breast cancer cases are ductal carcinoma in situ (DCIS), but little is known about DCIS risk factors. Recent studies suggest that some subtypes of DCIS (high grade or comedo) share histopathologic and epidemiologic characteristics with invasive disease, whereas others (medium or low grade or non-comedo) show different patterns. To investigate whether reproductive and hormonal risk factors differ among comedo and non-comedo types of DCIS and invasive breast cancer (IBC), we used a population-based case-control study of 1,808 invasive and 446 DCIS breast cancer cases and their age and race frequency-matched controls (1,564 invasive and 458 DCIS). Three or more full-term pregnancies showed a strong inverse association with comedo-type DCIS [odds ratio (OR), 0.53; 95% confidence interval (95% CI), 0.30-0.95] and a weaker inverse association for non-comedo DCIS (OR, 0.73; 95% CI, 0.42-1.27). Several risk factors (age at first full-term pregnancy, breast-feeding, and age at menopause) showed similar associations for comedo-type DCIS and IBC but different associations for non-comedo DCIS. Ten or more years of oral contraceptive showed a positive association with comedo-type DCIS (OR, 1.31; 95% CI, 0.70-2.47) and IBC (OR, 2.33; 95% CI, 1.06-5.09) but an inverse association for non-comedo DCIS (OR, 0.51; 95% CI, 0.25-1.04). Our results support the theory that comedo-type DCIS may share hormonal and reproductive risk factors with IBC, whereas the etiology of non-comedo DCIS deserves further investigation.

The effects of hormone replacement therapy on postmenopausal breast cancer biology and survival

BACKGROUND

The goal of this study was to compare the characteristics of breast cancers and survival rates in HRT users versus nonusers.

METHODS

Data were analyzed for 1055 patients > or = 50 years of age who had definitive therapy for breast cancer from 1994 through 2002.

RESULTS

There were 471 (45%) HRT users. The median age at diagnosis was 61.0 years for HRT users and 68.0 years for HRT nonusers (P < .001). HRT users more often had tumors that were <1 cm (P = .007), node negative (P = .033), and grade I (P = .016). HRT users had a decreased risk of death versus nonusers (hazard ratio = .438, 95% confidence limit = .263 to .729, P = .002).

CONCLUSIONS

HRT users developed breast cancer at a younger age than nonusers; HRT use was associated with the development of biologically more favorable cancers than those that developed in nonusers; and overall and disease-free survival rates were higher in HRT users than nonusers.

Menopausal hormone therapy and risk of clinical breast cancer subtypes

BACKGROUND

Breast cancer is a heterogeneous disease with subtypes that may vary in their etiologies. Menopausal hormone therapy has been associated more strongly with lobular and tubular than ductal histologic types and with tumors that are smaller, hormone receptor-positive, and of lower grade. At the same time, correlations have been observed between histology and clinical characteristics. To identify those tumor subtypes most strongly associated with hormone therapy use, it is necessary to disentangle these interrelationships.

METHODS

Based on 3,464 postmenopausal breast cancer cases and 6,657 controls from the population-based Mammary carcinoma Risk factor Investigation study, we used polytomous logistic regression to evaluate associations between hormone therapy use and risk of invasive breast cancer subtypes. We assessed variations in risk for selected tumor characteristics among histologic and hormone receptor subtypes, both overall and for specific hormone therapy regimens.

RESULTS

Lobular and mixed types showed less variation by prognostic factors than did ductal tumors. Current hormone therapy use had the strongest associations with prognostic variables in estrogen receptor (ER)-positive and/or progesterone receptor (PR)-positive ductal tumors and in lobular tumors regardless of ER/PR status, with little effect on ER/PR-negative ductal tumors. The observed associations varied minimally by hormone therapy type or regimen.

CONCLUSION

Current hormone therapy use was associated with more favorable breast cancer characteristics for ductal tumors but had less effect on prognostic characteristics in women with lobular tumors. Both histologic type and estrogen receptor/progesterone receptor status seem to be important in explaining the role of hormone therapy in the etiology of breast cancer subtypes.

Menopausal hormone therapy and breast cancer risk in the NIH-AARP Diet and Health Study Cohort

BACKGROUND

Results from the Women's Health Initiative trial raise new questions regarding the effects of estrogen therapy (ET) and estrogen plus progestin therapy (EPT) on breast cancer risk.

METHODS

We analyzed data from 126,638 females, ages 50 to 71 years at baseline, who completed two questionnaires (1995--1996 and 1996--1997) as part of the NIH-AARP Diet and Health Cohort Study and in whom 3,657 incident breast cancers were identified through June 30, 2002. Hormone-associated relative risks (RR) and 95% confidence intervals (CI) of breast cancer were estimated via multivariable regression models.

RESULTS

Among thin women (body mass index < 25 kg/m2), ET use was associated with a significant 60% excess risk after 10 years of use. EPT was associated with a significantly increased risk among women with intact uteri, with the highest risk among current, long-term (> or = 10 years) users (RR, 2.44; 95% CI, 2.13-2.79). These risks were slightly higher when progestins were prescribed continuously than sequentially (< 15 days/mo; respective RRs of 2.76 versus 2.01). EPT associations were strongest in thin women, but elevated risks persisted among heavy women. EPT use was strongly related to estrogen receptor (ER)-positive tumors, requiring consideration of this variable when assessing relationships according to other clinical features. For instance, ER- ductal tumors were unaffected by EPT use, but all histologic subgroups of ER+ tumors were increased, especially low-grade and mixed ductal-lobular tumors.

CONCLUSIONS

Both ET and EPT were associated with breast cancer risks with the magnitude of increase varying according to body mass and clinical characteristics of the tumors.

Breast cancer and hormonal therapy

Valid evidence from randomized-controlled trials indicates that breast cancer risk is increased with combined estrogen/progestogen use and that such treatment implies a risk greater than that of estrogen alone. Overall, risk estimates from observational studies are somewhat higher than in randomized-controlled trials but remain modest as compared with other risk factors even after long-term treatment. For combined estrogen/progestogen therapy, risk increases gradually to reach statistical significance after 4 to 5 years. Apart from its many beneficial health effects, the safety data for use of estrogen alone are quite reassuring. The only justifications for progestogen addition are for bleeding control and endometrial protection. At present, there are several new therapeutic compounds and concepts in development, which hold promise to provide both endometrial protection and breast safety.

Is breast cancer prognosis inherited?

INTRODUCTION

A genetic component is well established in the etiology of breast cancer. It is not well known, however, whether genetic traits also influence prognostic features of the malignant phenotype.

METHODS

We carried out a population-based cohort study in Sweden based on the nationwide Multi-Generation Register. Among all women with breast cancer diagnosed from 1961 to 2001, 2,787 mother-daughter pairs and 831 sister pairs with breast cancer were identified; we achieved complete follow-up and classified 5-year breast cancer-specific prognosis among proband (mother or oldest sister) into tertiles as poor, intermediary, or good. We used Kaplan-Meier estimates of survival proportions and Cox models to calculate relative risks of dying from breast cancer within 5 years depending on the proband's outcome.

RESULTS

The 5-year survival proportion among daughters whose mothers died within 5 years was 87% compared to 91% if the mother was alive (p = 0.03). Among sisters, the corresponding proportions were 70% and 88%, respectively (p = 0.001). After adjustment for potential confounders, daughters and sisters of a proband with poor prognosis had a 60% higher 5-year breast cancer mortality compared to those of a proband with good prognosis (hazard ratio [HR], 1.6; 95% confidence interval [CI], 1.2 to 2.2; p for trend 0.002). This association was slightly stronger among sisters (HR, 1.8; 95% CI, 1.0 to 3.4) than among daughters (HR, 1.6; 95% CI, 1.1 to 2.3).

CONCLUSION

Breast cancer prognosis of a woman predicts the survival in her first-degree relatives with breast cancer. Our novel findings suggest that breast cancer prognosis might be inherited.