The association of plasma DHEA and DHEA sulfate with breast cancer risk in predominantly premenopausal women.

Concentrations of adrenal androgens are positively associated with postmenopausal breast cancer risk; however, results in premenopausal women are conflicting. Therefore, we conducted a prospective nested case-control study within the Nurses' Health Study II cohort to examine the relationship of DHEA and DHEA sulfate (DHEAS) with breast cancer risk in predominantly premenopausal women. Blood samples were collected from 1996 to 1999. The analysis included 317 cases of breast cancer diagnosed after blood collection and before June 1, 2003; for each case, two controls were matched on age, fasting status, time of day and month of blood collection, race/ethnicity, and timing of blood draw within the menstrual cycle. No associations were observed between DHEA or DHEAS levels and breast cancer risk overall [in situ and invasive; DHEA relative risk (RR), top versus bottom quartile, 1.2; 95% confidence interval (95% CI), 0.8-1.8, P(trend) = 0.53; DHEAS RR, 1.3; 95% CI, 0.9-2.0; P(trend) = 0.07]. However, both DHEA and DHEAS were positively associated with estrogen receptor-positive/progesterone receptor-positive breast cancer (DHEA RR, 1.6; 95% CI, 0.9-2.8, P(trend) = 0.09; DHEAS RR, 1.9; 95% CI, 1.1-3.3, P(trend) = 0.02). We observed a significant interaction by age, with an RR for DHEAS of 0.8 (95% CI, 0.4-1.5, P(trend) = 0.62) for women <45 years old and 2.0 (95% CI, 1.2-3.5, P(trend) = 0.003) for women >/=45 years old; results were similar for DHEA. Our results suggest that adrenal androgens are positively associated with breast cancer among predominately premenopausal women, especially for estrogen receptor-positive/progesterone receptor-positive tumors and among women over age 45 years.     

Endogenous sex hormones and breast cancer in postmenopausal women: reanalysis of nine prospective studies

BACKGROUND: Reproductive and hormonal factors are involved in the etiology of breast cancer, but there are only a few prospective studies on endogenous sex hormone levels and breast cancer risk. We reanalyzed the worldwide data from prospective studies to examine the relationship between the levels of endogenous sex hormones and breast cancer risk in postmenopausal women. METHODS: We analyzed the individual data from nine prospective studies on 663 women who developed breast cancer and 1765 women who did not. None of the women was taking exogenous sex hormones when their blood was collected to determine hormone levels. The relative risks (RRs) for breast cancer associated with increasing hormone concentrations were estimated by conditional logistic regression on case-control sets matched within each study. Linear trends and heterogeneity of RRs were assessed by two-sided tests or chi-square tests, as appropriate. RESULTS: The risk for breast cancer increased statistically significantly with increasing concentrations of all sex hormones examined: total estradiol, free estradiol, non-sex hormone-binding globulin (SHBG)-bound estradiol (which comprises free and albumin-bound estradiol), estrone, estrone sulfate, androstenedione, dehydroepiandrosterone, dehydroepiandrosterone sulfate, and testosterone. The RRs for women with increasing quintiles of estradiol concentrations, relative to the lowest quintile, were 1.42 (95% confidence interval [CI] = 1.04 to 1.95), 1.21 (95% CI = 0.89 to 1.66), 1.80 (95% CI = 1.33 to 2.43), and 2.00 (95% CI = 1.47 to 2.71; P(trend)<.001); the RRs for women with increasing quintiles of free estradiol were 1.38 (95% CI = 0.94 to 2.03), 1.84 (95% CI = 1.24 to 2.74), 2.24 (95% CI = 1.53 to 3.27), and 2.58 (95% CI = 1.76 to 3.78; P(trend)<.001). The magnitudes of risk associated with the other estrogens and with the androgens were similar. SHBG was associated with a decrease in breast cancer risk (P(trend) =.041). The increases in risk associated with increased levels of all sex hormones remained after subjects who were diagnosed with breast cancer within 2 years of blood collection were excluded from the analysis. CONCLUSION: Levels of endogenous sex hormones are strongly associated with breast cancer risk in postmenopausal women.     

Circulating steroid hormone concentrations in postmenopausal women in relation to body size and composition

Steroid hormones are associated with the risk of postmenopausal breast cancer and evidence suggests that increased concentrations of oestrogens from peripheral aromatisation in adipose tissue partly explains the association between body mass index (BMI) and risk of postmenopausal breast cancer. This study examined the associations between circulating concentrations of steroid hormones and anthropometric measurements in a sample of naturally postmenopausal women from the Melbourne Collaborative Cohort Study, not using hormone replacement therapy. We measured plasma concentration of total oestradiol, oestrone sulphate, dehydroepiandrosterone sulphate, androstenedione, testosterone and sex hormone binding globulin (SHBG) and calculated concentration of free oestradiol. Body measurements included height, weight, BMI, waist circumference, fat mass and fat-free mass, the last two estimated by bioelectrical impedance analysis. BMI was positively associated with both oestrogens and androgens and negatively with SHBG. Fat mass was the principal measure responsible for the association observed between body size and total oestradiol. The associations between oestrone sulphate and androgens and body size were mainly with waist circumference. The associations between oestrogens and body size were close to null for the first 6 years since menopause and became positive thereafter. Our results are compatible with the hypothesis that after the menopause excess fat mass increases oestrogen concentrations through the peripheral aromatisation of androgens in adipose tissue. This effect requires around 6 years to be detectable by way of circulating steroid hormone levels.     

Serum androgens and prostate cancer among 643 cases and 643 controls in the European Prospective Investigation into Cancer and Nutrition

We examined the hypothesis that serum concentrations of circulating androgens and sex hormone binding globulin (SHBG) are associated with risk for prostate cancer in a case-control study nested in the European Prospective Investigation into Cancer and Nutrition (EPIC). Concentrations of androstenedione, testosterone, androstanediol glucuronide and SHBG were measured in serum samples for 643 prostate cancer cases and 643 matched control participants, and concentrations of free testosterone were calculated. Conditional logistic regression models were used to calculate odds ratios for risk of prostate cancer in relation to the serum concentration of each hormone. After adjustment for potential confounders, there was no significant association with overall risk for prostate cancer for serum total or free testosterone concentrations (highest versus the lowest thirds: OR, 1.02; 95% CI, 0.73-1.41 and OR, 1.07, 95% CI, 0.74-1.55, respectively) or for other androgens or SHBG. Subgroup analyses showed significant heterogeneity for androstenedione by cancer stage, with a significant inverse association of androstenedione concentration and risk for advanced prostate cancer. There were also weak positive associations between free testosterone concentration and risk for total prostate cancer among younger men and risk for high-grade disease. In summary, in this large nested case-control study, concentrations of circulating androgens or SHBG were not strongly associated with risk for total prostate cancer. However, our findings are compatible with a positive association of free testosterone with risk in younger men and possible heterogeneity in the association with androstenedione concentration by stage of disease; these findings warrant further investigation.     

Postmenopausal serum sex steroids and risk of hormone receptor-positive and -negative breast cancer: a nested case-control study

Prediagnostic endogenous sex steroid hormone levels have well established associations with overall risk of breast cancer. While evidence toward the existence of distinct subtypes of breast cancer accumulates, few studies have investigated the associations of sex steroid hormone levels with risk of hormone receptor [estrogen receptor (ER) and/or progesterone receptor (PR)] defined breast cancer. In a case-control study nested within the EPIC cohort (European Prospective Investigation into Cancer and Nutrition), estradiol, testosterone, and sex hormone-binding globulin levels were measured in prediagnostic serum samples from postmenopausal women not using hormone replacement therapy at blood donation. A total of 554 women who developed invasive breast cancer with information on receptor status were matched with 821 control subjects. Conditional logistic regression models estimated breast cancer risk with hormone concentrations according to hormone receptor status of the tumor. Sex steroid hormones were associated with risks of not only ER+PR+ breast cancer [estradiol OR for highest vs. lowest tertile = 2.91 (95% CI: 1.62-5.23), P(trend) = 0.002; testosterone OR = 2.27 (95% CI: 1.35-3.81), P(trend) = 0.002] but also of ER-PR- breast cancer [estradiol OR = 2.11 (95% CI: 1.00-4.46), P(trend) = 0.05; testosterone OR = 2.06 (95% CI: 0.95-4.46), P(trend) = 0.03], with associations appearing somewhat stronger in the receptor-positive disease. Serum androgens and estrogens are associated with risks of both hormone receptor-negative as well as receptor-positive breast tumors. Further research is needed to establish through which molecular pathways, and during which evolutionary stages of development, androgens and estrogens can promote the occurrence of both receptor-positive and -negative clinical breast tumors.     

Premenopausal serum androgens and breast cancer risk: a nested case-control study

Introduction

Prospective epidemiologic studies have consistently shown that levels of circulating androgens in postmenopausal women are positively associated with breast cancer risk. However, data in premenopausal women are limited.

Methods

A case-control study nested within the New York University Women's Health Study was conducted. A total of 356 cases (276 invasive and 80 in situ) and 683 individually-matched controls were included. Matching variables included age and date, phase, and day of menstrual cycle at blood donation. Testosterone, androstenedione, dehydroandrosterone sulfate (DHEAS) and sex hormone-binding globulin (SHBG) were measured using direct immunoassays. Free testosterone was calculated.

Results

Premenopausal serum testosterone and free testosterone concentrations were positively associated with breast cancer risk. In models adjusted for known risk factors of breast cancer, the odds ratios for increasing quintiles of testosterone were 1.0 (reference), 1.5 (95% confidence interval (CI), 0.9 to 2.3), 1.2 (95% CI, 0.7 to 1.9), 1.4 (95% CI, 0.9 to 2.3) and 1.8 (95% CI, 1.1 to 2.9; P _trend = 0.04), and for free testosterone were 1.0 (reference), 1.2 (95% CI, 0.7 to 1.8), 1.5 (95% CI, 0.9 to 2.3), 1.5 (95% CI, 0.9 to 2.3), and 1.8 (95% CI, 1.1 to 2.8, P _trend = 0.01). A marginally significant positive association was observed with androstenedione (P = 0.07), but no association with DHEAS or SHBG. Results were consistent in analyses stratified by tumor type (invasive, in situ), estrogen receptor status, age at blood donation, and menopausal status at diagnosis. Intra-class correlation coefficients for samples collected from 0.8 to 5.3 years apart (median 2 years) in 138 cases and 268 controls were greater than 0.7 for all biomarkers except for androstenedione (0.57 in controls).

Conclusions

Premenopausal concentrations of testosterone and free testosterone are associated with breast cancer risk. Testosterone and free testosterone measurements are also highly reliable (that is, a single measurement is reflective of a woman's average level over time). Results from other prospective studies are consistent with our results. The impact of including testosterone or free testosterone in breast cancer risk prediction models for women between the ages of 40 and 50 years should be assessed. Improving risk prediction models for this age group could help decision making regarding both screening and chemoprevention of breast cancer.     

Circulating steroid hormones and the risk of prostate cancer.

Epidemiologic studies have failed to support the hypothesis that circulating androgens are positively associated with prostate cancer risk and some recent studies have even suggested that high testosterone levels might be protective particularly against aggressive cancer. We tested this hypothesis by measuring total testosterone, androstanediol glucuronide, androstenedione, DHEA sulfate, estradiol, and sex hormone-binding globulin in plasma collected at baseline in a prospective cohort study of 17,049 men. We used a case-cohort design, including 524 cases diagnosed during a mean 8.7 years follow-up and a randomly sampled sub-cohort of 1,859 men. The association between each hormone level and prostate cancer risk was tested using Cox models adjusted for country of birth. The risk of prostate cancer was approximately 30% lower for a doubling of the concentration of estradiol but the evidence was weak (P(trend)=0.07). None of the other hormones was associated with overall prostate cancer (P(trend) >or= 0.3). None of the hormones was associated with nonaggressive prostate cancer (all P(trend) >or= 0.2). The hazard ratio [HR; 95% confidence interval (95% CI)] for aggressive cancer almost halved for a doubling of the concentration of testosterone (HR, 0.55; 95% CI, 0.32-0.95) and androstenedione (HR, 0.51; 95% CI, 0.31-0.83), and was 37% lower for a doubling of the concentration of DHEA sulfate (HR, 0.63; 95% CI, 0.46-0.87). Similar negative but nonsignificant linear trends in risk for aggressive cancer were obtained for free testosterone, estradiol, and sex hormone-binding globulin (P(trend)=0.06, 0.2, and 0.1, respectively). High levels of testosterone and adrenal androgens are thus associated with reduced risk of aggressive prostate cancer but not with nonaggressive disease.     

Human mammary cancer as a site of sex steroid metabolism

Oestrogen-progesterone imbalance in favour of the oestrogens is considered to be an important factor in the development of mammary cancer, although oestrogens are not directly mitogenic. Moreover, this promoter effect of carcinogenesis may be limited in time. Except for increased plasma (free) oestradiol levels, plasma sex hormone levels in breast cancer patients are comparable to those in normal women, matched for age and weight. In both benign and malignant breast tissue, sex hormone concentrations (ng/g) are significantly higher than in plasma (ng/mg), except for dehydroepiandrosterone sulphate, oestrone sulphate and testosterone, but in breast cancer tissues, dehydroepiandrosterone sulphate (DHEAS), 5 alpha-androstane-3 alpha-17 beta-diol and progesterone concentrations are lower than in normal breast tissue. As to the origin of these sex hormones in breast tissue, a positive arteriovenous gradient across the breast tissue has been observed for androstenedione and oestradiol, suggesting uptake from plasma by the tissues. Aromatization of androstenedione, on the other hand, is probably only a minor source of oestrogens in breast tissue. Hydrolysis of oestrone sulphate taken up from the blood, or oestradiol-17 beta fatty acid esters may be another source, but data are too scarce at present to draw a final conclusion as to their role as source of tissue oestrogens. 17 beta-hydroxysteroid dehydrogenase activity, inactivating oestradiol into oestrone, may be an important determinant of tissue oestradiol concentration. This enzyme activity was found to be higher in oestrogen receptor positive than in oestrogen receptor negative tissues and was negatively correlated with DHEA and DHEAS concentrations. As it was shown that the latter two steroids are non-competitive inhibitors of the 17 beta-hydroxysteroid dehydrogenase as well as of the oestrogen-sulphotransferase, it appears that DHEA may be an important modulator of tissue oestradiol concentration, whereas the 17 beta-hydroxysteroid dehydrogenase might constitute an additional marker of hormone dependency of breast cancer.     

Circulating levels of sex steroid hormones and risk of endometrial cancer in postmenopausal women

Experimental and epidemiological data support a role for sex steroid hormones in the pathogenesis of endometrial cancer. The associations of pre‐diagnostic blood concentrations of estradiol, estrone, testosterone, androstenedione, DHEAS and SHBG with endometrial cancer risk were investigated. A case‐control study was nested within 3 cohorts in New York (USA), Umeå (Sweden) and Milan (Italy). Cases were 124 postmenopausal women with invasive endometrial cancer. For each case, 2 controls were selected, matching the case on cohort, age and date of recruitment. Only postmenopausal women who did not use exogenous hormones at the time of blood donation were included. Odds ratios (OR) and their 95% confidence intervals (CI) were estimated by conditional logistic regression. ORs (95% CI) for endometrial cancer for quartiles with the highest hormone levels, relative to the lowest were as follows: 4.13 (1.76–9.72), p_trend = 0.0008 for estradiol, 3.67 (1.71–7.88), p_trend = 0.0007 for estrone, 2.15 (1.05–4.40), p_trend = 0.04 for androstenedione, 1.74 (0.88–3.46), p_trend = 0.06 for testosterone, 2.90 (1.42–5.90), p_trend = 0.002 for DHEAS and 0.46 (0.20–1.05), p_trend = 0.01 for SHBG after adjustment for body mass index, use of oral contraceptives and hormone replacement therapy. The results of our multicenter prospective study showed a strong direct association of circulating estrogens, androgens and an inverse association of SHBG levels with endometrial cancer in postmenopausal women. The effect of elevated androstenedione and testosterone levels on disease risk seems to be mediated mainly through their conversion to estrogens, although an independent effect of androgens on tumor growth cannot be ruled out, in particular in the years close to diagnosis. © 2003 Wiley‐Liss, Inc.     

Endogenous steroid hormone levels in early pregnancy and risk of testicular cancer in the offspring: A nested case–referent study

According to the leading hypothesis on testicular cancer (TC) etiology exposure to a specific pattern of steroid hormones in utero, in particular, to high levels of estrogens and low levels of androgens is the major determinant of TC risk in the offspring. We performed a case–referent study nested within Finnish, Swedish and Icelandic maternity cohorts exploiting early pregnancy serum samples to evaluate the role of maternal endogenous steroid hormones with regard to the risk of TC. TC cases and referents were aged between 0 and 25 years. For each case‐index mother pair, three or four matched referent‐referent mother pairs were identified using national population registries. First trimester or early second trimester sera were retrieved from the index mothers of 73 TC cases and 286 matched referent mothers, and were tested for dehydroepiandrosterone sulfate (DHEAS), androstenedione, testosterone, estradiol, estrone, and sex hormone binding globulin (SHBG). Offspring of mothers with high DHEAS levels had a significantly decreased risk of TC (OR for highest vs. lowest DHEAS quartile, 0.18 (95% CI 0.06–0.58). In contrast, offspring of mothers with high androstenedione levels had an increased risk of TC (OR 4.1; 95% CI 1.2–12.0). High maternal total estradiol level also tended to be associated with an increased risk of TC in the offspring (OR 32; 95% CI 0.98–1,090). We report the first direct evidence that interplay of maternal steroid hormones in the early pregnancy is important in the etiology of TC in the offspring. © 2009 UICC     

Birthweight and body size throughout life in relation to sex hormones and prolactin concentrations in premenopausal women.

The association of birthweight and body size throughout life with premenopausal breast cancer risk may be due, in part, to relationships with sex hormones. Therefore, we assessed whether birthweight, body shape at ages 5 and 10, body mass index (BMI) at age 18 and adulthood, adult waist circumference and waist-to-hip ratio (WHR), and attained height were associated with the plasma concentrations of estrogens, androgens, progesterone, prolactin, and sex hormone-binding globulin (SHBG) in 592 premenopausal women, ages 33 to 52 years old, from the Nurses' Health Study II. About 85% of women provided blood samples during follicular and luteal menstrual phases; other women had a single untimed sample. We observed few associations between sex hormone levels and birthweight or body shape in childhood. However, adult BMI was inversely associated with SHBG (P trend < 0.001) and positively associated with free testosterone (P trend < 0.001) concentrations. Adult BMI was not associated with follicular or luteal free estradiol levels (P trend >or= 0.15) because it was inversely associated with total estradiol levels (P trend < 0.001 for follicular and luteal estradiol levels). Testosterone, androstenedione, and progesterone were inversely associated with BMI. Comparing women with a BMI of >or=30 versus <20 kg/m2, levels were higher by 53% for free testosterone and lower by 51% for SHBG, 39% for follicular estradiol, 20% for luteal estradiol, 14% for androstenedione, 13% for testosterone, and 20% for progesterone. We observed no clear associations between BMI at age 18, waist circumference, WHR, or height, and sex hormone concentrations. Our results suggest that effects on premenopausal sex hormone levels may be one mechanism through which adult adiposity, but not birthweight or childhood body size, affects premenopausal breast cancer risk.     

Premenopausal Circulating Androgens and Risk of Endometrial Cancer: results of a Prospective Study

Endometrial cancer risk is increased by estrogens unopposed by progesterone. In premenopausal women, androgen excess is often associated with progesterone insufficiency, suggesting that premenopausal androgen concentrations may be associated with risk. In a case–control study nested within three cohorts, we assessed the relationship between premenopausal androgens and risk of endometrial cancer (161 cases and 303 controls matched on age and date of blood donation). Testosterone, DHEAS, androstenedione, and SHBG were measured in serum or plasma. Free testosterone was calculated from testosterone and SHBG. We observed trends of increasing risk across tertiles of testosterone (OR_T3-T1?=?1.59, 95 % CI?=?0.96, 2.64, p?=?0.08) and free testosterone (OR_T3-T1?=?1.76, 95 % CI?=?1.01, 3.07, p?=?0.047), which were not statistically significant after adjustment for body mass index (BMI). There was no association for DHEAS, androstenedione, or SHBG. There were significant interactions by age at diagnosis (<55 years, n?=?51 cases; ≥55 years, n?=?110 cases). Among women who were ≥55 years of age (predominantly postmenopausal) at diagnosis, the BMI-adjusted OR was 2.08 (95 % CI?=?1.25, 3.44, p?=?0.005) for a doubling in testosterone and 1.55 (95 % CI?=?1.04, 2.31, p?=?0.049) for a doubling in free testosterone. There was no association among women aged <55 years at diagnosis, consistent with the only other prospective study to date. If pre- and post-menopausal concentrations of androgens are correlated, our observation of an association of premenopausal androgens with risk among women aged ≥55 years at diagnosis could be due to the effect on the endometrium of postmenopausal androgen-derived estrogens in the absence of progesterone, which is no longer secreted.     

Postmenopausal endogenous oestrogens and risk of endometrial cancer: results of a prospective study

We assessed the association of postmenopausal serum levels of oestrogens and sex hormone-binding globulin (SHBG) with endometrial cancer risk in a case-control study nested within the NYU Women's Health Study cohort. Among 7054 women postmenopausal at enrolment, 57 cases of endometrial cancer were diagnosed a median of 5.5 years after blood donation. Each case was compared to 4 controls matched on age, menopausal status at enrolment, and serum storage duration. Endometrial cancer risk increased with higher levels of oestradiol (odds ratio = 2.4 in highest vs lowest tertile, P for trend = 0.02), percent free oestradiol (OR = 3.5, P< 0.001), and oestrone (OR = 3.9, P< 0.001). Risk decreased with higher levels of percent SHBG-bound oestradiol (OR = 0.43, P = 0.03) and SHBG (OR = 0.39, P = 0.01). Trends remained in the same directions after adjusting for height and body mass index. A positive association of body mass index with risk was substantially reduced after adjusting for oestrone level. Our results indicate that risk of endometrial cancer increases with increasing postmenopausal oestrogen levels but do not provide strong support for a role of body mass index independent of its effect on oestrogen levels.     

Serum concentrations of estrogens, sex hormone binding globulin, and androgens and risk of breast hyperplasia in postmenopausal women.

OBJECTIVE: We sought to determine whether serum concentrations of estrogens, androgens, and sex hormone binding globulin in postmenopausal women were related to the presence of mammary hyperplasia, an established breast cancer risk factor. METHODS: Study participants provided serum before breast biopsy or mastectomy in three hospitals in Grand Rapids, Michigan, between 1977 and 1987. A total of 179 subjects with breast hyperplasia were compared with 152 subjects with nonproliferative breast changes that are not associated with increased breast cancer risk. RESULTS: The odds ratios (OR) associated with the three upper quartiles of estradiol in comparison with the lowest quartile were 2.2 [95% confidence interval (95% CI) 1.1-4.6], 2.5 (95% CI, 1.1-5.3), and 4.1 (95% CI, 2.0-8.5; Ptrend = 0.007). The corresponding ORs for bioavailable estradiol, estrone, and estrone sulfate were of generally similar magnitude (Ptrend = 0.003 for bioavailable estradiol, 0.0004 for estrone, and 0.0009 for estrone sulfate). Relative to women concurrently in the lowest tertile for serum estradiol, estrone, and estrone sulfate, women concurrently in the highest tertile for all three hormones had an OR of 5.8 (95% CI, 2.2-15.2). Serum concentrations of sex hormone binding globulin, testosterone, dehydroepiandrosterone, androstenedione, and androstenediol were not associated with risk of hyperplasia. CONCLUSIONS: Serum concentrations of estrogens, but not of androgens or sex hormone binding globulin, were strongly and significantly associated with risk of breast hyperplasia in postmenopausal women, suggesting that estrogens are important early in the pathologic process towards breast cancer.     

Urinary endogenous sex hormone levels and the risk of postmenopausal breast cancer

To assess the relation between urinary endogenous sex steroid levels and the risk of postmenopausal breast cancer, a nested case-cohort study was conducted within a large cohort (the DOM cohort) in the Netherlands (n=9,349). Until the end of follow-up (1 January 1996), 397 postmenopausal breast cancer cases were identified and a subcohort of 424 women was then taken from all eligible women. Women using hormones were excluded, leaving 364 breast cancer cases and 382 women in the subcohort for the analyses. Concentrations of oestrone, oestradiol, testosterone, 5alpha-androstane-3alpha, 17beta-diol and creatinine were measured in first morning urine samples, which had been stored since enrolment at -20 degrees C. A Cox proportional Hazards model was used, with Barlow's adjustment for case-cohort sampling, to estimate breast cancer risk in quartiles of each of the, creatinine corrected, hormone levels, the lowest quartile being the reference group. Women with higher levels of all four of the hormones were at increased risk for postmenopausal breast cancer (highest vs lowest quartile: incidence rate ratio for oestrone (IRR(oestrone)=2.5, 95% CI: 1.6-3.8; IRR(oestradiol)=1.5, 95% CI: 1.0-2.3; IRR(testosterone)=1.6, 95% CI: 1.0-2.4; IRR(5alpha-androstane-3alpha, 17beta-diol)=1.7, 95% CI: 1.1-2.7). In conclusion, women with higher excretion levels of both oestrogens and androgens have an increased risk of breast cancer.     

A prospective study of urinary oestrogen excretion and breast cancer risk.

To test the hypothesis that high levels of endogenous oestrogens increase the risk for developing breast cancer, concentrations of oestrone, oestradiol and oestriol were measured in 24 h urine samples from 1000 women participants in a prospective study of breast cancer on the island of Guernsey. Sixty-nine subjects were diagnosed with breast cancer subsequent to urine collection. Among women who were premenopausal at the time of urine collection, cases excreted less oestrogen than controls; the odds ratios (95% CI) for breast cancer in the middle and upper thirds of the distribution of oestrogen excretion, in comparison with the lower third (reference group, assigned odds ratio = 1.0), were 0.5(0.2-1.2) and 0.4(0.2-1.1) respectively for oestrone, 0.8(0.4-1.8 and 0.4(0.2-1.1) for oestradiol, 0.7(0.3-1.6) and 0.7(0.3-1.6) for oestriol and 0.9(0.4-2.0) and 0.5(0.2-1.3) for total oestrogens. Among women who were post-menopausal at the time of urine collection, the trend was in the opposite direction, with an increase in risk associated with increased oestrogen excretion; the odds ratios were 0.9(0.3-2.2) and 1.1(0.5-2.8) for oestrone, 0.8(0.3-2.3) and 1.9(0.8-4.6) for oestradiol, 1.5(0.6-3.9) and 1.8(0.7-4.6) for oestriol and 0.9(0.4-2.6) and 1.9(0.7-4.7) for total oestrogens. The trends of increasing risk with increasing oestrogen excretion among post-menopausal women were statistically significant for oestradiol (P = 0.022) and for total oestrogens (P = 0.016). We conclude that high levels of endogenous oestrogens in post-menopausal women are associated with increased breast cancer risk, but that the relationship of oestrogens in premenopausal women with risk is unclear.     

Lifetime cumulative number of menstrual cycles and serum sex hormone levels in postmenopausal women

Objective Lifetime cumulative number of menstrual cycles is related to breast cancer risk. The aim of this study is to investigate the relation between this index and serum sex hormone levels in postmenopausal women. Methods Cross-sectional study including 860 naturally postmenopausal Dutch participants of the European Prospective Investigation into Cancer and Nutrition. Lifetime cumulative number of menstrual cycles was computed using questionnaire data on ages at menarche and menopause, number of pregnancies, breastfeeding, oral contraceptive use (OC) and regularity pattern. Measurements of hormones included estrone (E1), estradiol (E2), andostrenedione, testosterone, sex-hormone binding globulin (SHBG) and dehydroepiandrostenedione sulfate (DHEAS). The relation between the lifetime cumulative number of menstrual cycles and hormone levels was assessed using analysis of covariance. Relations between reproductive characteristics and hormone levels were also studied. Adjustments for characteristics at blood collection included age, years since menopause, BMI, hormone replacement therapy use, OC use, smoking habits, alcohol intake and physical activity were done. Results Lifetime cumulative number of cycles was related with SHBG; participants in the lowest category had higher SHBG levels. For the separate characteristics, DHEAS and androstenedione increased significantly with increasing age at menarche, while androstenedione and testosterone decreased with increasing age at menopause. For the parity characteristics, SHBG levels increased according to the number of live births. Conclusions Lifetime cumulative number menstrual cycles was related only to SHBG. Therefore, free levels of estrogens or androgens may be related to this number of menstrual cycles estimate, reflecting lifetime exposure to ovarian hormones.     

Associations of alcohol, height, and reproductive factors with serum hormone concentrations in postmenopausal Japanese women

We measured serum levels of estradiol (E₂), sex hormone-binding globulin (SHBG), progesterone, and dehydroepiandrosterone sulfate (DHEAS) in 61 postmenopausal women drawn from female residents in a community in Japan to evaluate the relationships between these hormone levels and potential breast cancer risk factors. The information on reproductive history, body size, alcohol use, and physical activity was obtained by means of a self-administered questionnaire. There was a significant trend in increasing E₂ level with increasing height after taking account of age and body mass index (BMI) (p for trend = 0.04). BMI was inversely associated with SHBG level after controlling for age (p for trend = 0.01). Decreasing progesterone with increasing BMI was observed after controlling age and history of hysterectomy (P=0.05). Alcohol consumption was positively associated with E₂ level and there was a strong linear trend after controlling for age, height, and BMI (p for trend=0.001). Trend for increasing DHEAS with alcohol consumption was also statistically significant after controlling for age and history of hysterectomy (p for trend=0.01). Reproductive factors as well as physical activity were not related to any of the hormone levels.     

Serum levels of sex hormones and breast cancer risk in premenopausal women: a case–control study (USA)

High levels of serum estrogens and androgens have been convincingly linked with an increased risk of breast cancer among postmenopausal women. By contrast, the role of blood levels of these hormones in the etiology of premenopausal breast cancer is not well understood. In a case-control study, we sought to examine associations between levels of serum estradiol, sex-hormone binding globulin (SHBG), dehydroepiandrosterone (DHEA), testosterone, androstenedione and progesterone and risk of premenopausal breast cancer. Cases of breast cancer under age 45 were identified using rapid ascertainment systems in Seattle/Puget Sound, Washington and control subjects were identified from the same area through random digit dialing methods. A total of 169 eligible breast cancer cases and 195 control subjects donated blood (either before or six or more weeks after surgery) and were interviewed using a standardized questionnaire. The fully adjusted risk ratios and 95% confidence intervals for the highest versus lowest tertiles of estradiol, according to menstrual cycle phase, were 3.10 (0.8-12.7) for early follicular, 0.54 (0.2-1.7) for late follicular and 0.60 (0.3-1.4) for luteal. Risks for highest versus lowest quartiles of SHBG and androgens were 0.81 (0.4-1.6) for SHBG, 2.42 (1.1-5.2) for DHEA, 1.12 (0.6-2.5) for testosterone, and 1.33 (0.6-2.8) for androstenedione. For luteal progesterone, the RR for the highest versus lowest tertile was 0.55 (0.2-1.4). In summary, we did not find a convincing association between serum SHBG, estradiol, testosterone or androstenedione and premenopausal breast cancer risk. Observed differences between cases and controls subjects in serum levels of DHEA and luteal phase progesterone should be investigated further in large prospective studies.     

Endogenous sex hormones and prostate cancer: a quantitative review of prospective studies.

This paper presents a quantitative review of the data from eight prospective epidemiological studies, comparing mean serum concentrations of sex hormones in men who subsequently developed prostate cancer with those in men who remained cancer free. The hormones reviewed have been postulated to be involved in the aetiology of prostate cancer: androgens and their metabolites testosterone (T), non-SHBG-bound testosterone (non-SHBG-bound T), di-hydrotestosterone (DHT), androstanediol glucuronide (A-diol-g), androstenedione (A-dione), dehydroepiandrosterone sulphate (DHEAS), sex hormone binding globulin (SHBG), the oestrogens, oestrone and oestradiol, luteinizing hormone (LH) and prolactin. The ratio of the mean hormone concentration in prostate cancer cases to that of controls (and its 95% confidence interval (CI)) was calculated for each study, and the results summarized by calculating the weighted average of the log ratios. No differences in the average concentrations of the hormones were found between prostate cancer cases and controls, with the possible exception of A-diol-g which exhibited a 5% higher mean serum concentration among cases relative to controls (ratio 1.05, 95% CI 1.00-1.11), based on 644 cases and 1048 controls. These data suggest that there are no large differences in circulating hormones between men who subsequently go on to develop prostate cancer and those who remain free of the disease. Further research is needed to substantiate the small difference found in A-diol-g concentrations between prostate cancer cases and controls.