Background: Median overall survival (OS) for women with high-grade serous ovarian cancer (HGSOC) is similar to 4 years, yet survival varies widely between patients. There are no well-established, gene expression signatures associated with prognosis. The aim of this study was to develop a robust prognostic signature for OS in patients with HGSOC. Patients and methods: Expression of 513 genes, selected from a meta-analysis of 1455 tumours and other candidates, was measured using NanoString technology from formalin-fixed paraffin-embedded tumour tissue collected from 3769 women with HGSOC from multiple studies. Elastic net regularization for survival analysis was applied to develop a prognostic model for 5-year OS, trained on 2702 tumours from 15 studies and evaluated on an independent set of 1067 tumours from six studies. Results: Expression levels of 276 genes were associated with OS (false discovery rate < 0.05) in covariate-adjusted single-gene analyses. The top five genes were TAP1, ZFHX4, CXCL9, FBN1 and PTGER3 (P < 0.001). The best performing prognostic signature included 101 genes enriched in pathways with treatment implications. Each gain of one standard deviation in the gene expression score conferred a greater than twofold increase in risk of death [hazard ratio (HR) 2.35, 95% confidence interval (CI) 2.02-2.71; P < 0.001]. Median survival [HR (95% CI)] by gene expression score quintile was 9.5 (8.3 to -), 5.4 (4.6-7.0), 3.8 (3.3-4.6), 3.2 (2.9-3.7) and 2.3 (2.1-2.6) years. Conclusion: The OTTA-SPOT (Ovarian Tumor Tissue Analysis consortium - Stratified Prognosis of Ovarian Tumours) gene expression signature may improve risk stratification in clinical trials by identifying patients who are least likely to achieve 5-year survival. The identified novel genes associated with the outcome may also yield opportunities for the development of targeted therapeutic approaches.

Introduction/Background Only ∼15% of patients with high-grade serous ovarian cancer (HGSC) survive >10 years. Those patients with a more typical disease trajectory may benefit from insights gained from long-term survivors (LTS). Here, we investigated genomic and immunologic determinants of exceptional survival in vivo and in vitro with a focus on the tumour suppressor RB1. Methodology Whole-genome sequencing (WGS) was performed on a unique set of primary tumors and germline samples from a cohort of 55 women with >10-year survival following a diagnosis of advanced stage (Stage IIIC/IV) HGSC. Tumors were also characterised by RNA sequencing and immunohistochemistry (IHC). RB1 was depleted in HGSC cell lines through CRISPR-Cas9 knockout (KO). The impact of RB1 loss was analysed in assays of chemosensitivity, clonogenicity, immunogenicity and transcriptomics. Results WGS showed that somatic inactivation of RB1 was common in LTS, with 33% of tumours showing loss of RB1 protein by IHC compared to 13% of unselected HGSC controls (n=207; P=0.001). IHC revealed that RB1 loss was associated with increased numbers of PD-1+ tumour-infiltrating lymphocytes (P=0.015) and MHC class I on tumor cells (P=0.002). In an independent HGSC cohort (n=847) from the OTTA consortium, co-occurrence of germline BRCA1/2 mutations and RB1 loss was associated with a significantly longer overall survival than patients with intact BRCA1/2 and RB1 (HR: 0.44, P<0.001). In RB1 negative tumours, top enriched pathways involved E2F targets and interferon response genes. RB1 KO impaired clonogenic survival after cisplatin/paclitaxel combination therapy specifically in the BRCA1 mutant cell line JHOS2 (P <0.01). Expression of immune markers MHC Class II and PD-L1 was increased in RB1 KO cells. Conclusion In HGSC, concurrent loss of RB1 and BRCA1/2 mutation is associated with significantly longer overall survival. RB1 loss appears to result in impaired self-renewal after standard chemotherapy and enhanced host immune response. Disclosure F.A.M.S is supported by a Swiss National Foundation Early Postdoc Mobility Fellowship, a Swiss Cancer Research Foundation grant and the Prof. Dr. Max Cloëtta foundation. D.W.G. is supported by U.S. Army Medical Research and Materiel Command grant. AOCS receives funding support from Astra Zeneca and Ovarian Cancer Australia. C.L.P. and M.C.P. acknowledge support from the US Congressionally Directed Ovarian Cancer Research Program administered by the US Army Medical research and Materiel Command, grant number W81XWH-16-2-0010. D.D.L.B. is supported by U.S. Army Medical Research and Materiel Command grant, by the National Health and Medical Research Council of Australia (NHMRC) grants APP1092856 and APP1117044, the US National Cancer Institute U54 program, and receives research funding from Astra Zeneca, Beigene and Genentech-Roche. A.deF. is supported by grants from the U.S. Army Medical Research and Materiel Command, NHMRC, Cancer Institute NSW, Cancer Council New South Wales and AstraZeneca.

OBJECTIVE:The Silva invasion pattern-based classification system stratifies endocervical adenocarcinomas (ECAs) into 3 categories corresponding to risk of metastasis and recurrence, but has only been evaluated for HPV-associated ECAs of usual type. We examined whether the Silva system is applicable to all endocervical adenocarcinomas, especially those not associated with HPV. METHODS:Complete slide sets from 341 surgical specimens of ECA were collected from 7 institutions worldwide. All specimens were associated with clinical records covering at least 5 years of follow-up. Tumors were classified as HPV-associated (HPVA) or not (NHPVA) by both morphology and detection of HPV using in situ hybridization. Recurrence and survival were analyzed by multivariate Mantel-Haenszel methods. RESULTS:Most specimens (292; 85.6%) were HPVA, while 49 (14.3%) were NHPVA. All NHPVAs were Silva pattern C, while 76.0% of HPVAs were pattern C, 14.7% pattern A, and 9.3% pattern B. Including both HPVAs and NHPVAs, lymphovascular invasion (LVI) was detected in 0% of pattern A, 18.5% of pattern B and 62.6% of pattern C cases (p < 0.001). None of the pattern A or B cases were associated with lymph node metastases (LNM), in contrast to pattern C cases (21.8%). Among patients with Silva pattern C ECA, those with HPVA tumors had a lower recurrence rate and better survival than those with NHPVA; however, when adjusted for stage at diagnosis, the difference in recurrence and mortality was small and not statistically significant. CONCLUSIONS:Application of the Silva system is only relevant in HPVA cervical adenocarcinoma.

BACKGROUND:Nulliparity is an endometrial cancer risk factor, but whether or not this association is due to infertility is unclear. Although there are many underlying infertility causes, few studies have assessed risk relations by specific causes.METHODS:We conducted a pooled analysis of 8153 cases and 11 713 controls from 2 cohort and 12 case-control studies. All studies provided self-reported infertility and its causes, except for one study that relied on data from national registries. Logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI).RESULTS:Nulliparous women had an elevated endometrial cancer risk compared with parous women, even after adjusting for infertility (OR=1.76; 95% CI: 1.59-1.94). Women who reported infertility had an increased risk compared with those without infertility concerns, even after adjusting for nulliparity (OR=1.22; 95% CI: 1.13-1.33). Among women who reported infertility, none of the individual infertility causes were substantially related to endometrial cancer.CONCLUSIONS:Based on mainly self-reported infertility data that used study-specific definitions of infertility, nulliparity and infertility appeared to independently contribute to endometrial cancer risk. Understanding residual endometrial cancer risk related to infertility, its causes and its treatments may benefit from large studies involving detailed data on various infertility parameters.

Mammographic density (MD), representing connective and epithelial tissue (fibroglandular tissue, FGT) is a major risk factor for breast cancer. In an analysis of an autopsy series (Bartow SA, Pathak DR, Mettler FA. Radiographic microcalcification and parenchymal patterns as indicators of histologic "high-risk" benign breast disease. Cancer 1990; 66: 1721-1725, Bartow SA, Pathak DR, Mettler FA et al. Breast mammographic pattern: a concatenation of confounding and breast cancer risk factors. Am J Epidemiol 1995; 142: 813-819), MD was found to be strongly correlated with the collagen and epithelial content of the breast (Li T, Sun L, Miller N et al. The association of measured breast tissue characteristics with MD and other risk factors for breast cancer. Cancer Epidemiol Biomarkers Prev 2005; 14: 343-349), and another report showed that breast epithelium was highly concentrated in the areas of collagen concentration (Hawes D, Downey S, Pearce CL et al. Dense breast stromal tissue shows greatly increased concentration of breast epithelium but no increase in its proliferative activity. Breast Cancer Res 2006; 8: R24). Collagen comprises the overwhelming majority of the FGT, occupying an area on the slides obtained from the autopsy series some 15 times the area of glandular tissue. The relationship of MD with breast cancer risk appears likely to be due to a major extent to increasing epithelial cell numbers with increasing MD. FGT is also seen in breast magnetic resonance imaging (breast MRI) and, as expected, it has been shown that this measure of FGT (MRI-FGT) is highly correlated with MD. A contrast-enhanced breast MRI shows that normal FGT 'enhances' (background parenchymal enhancement, BPE) after contrast agent is administered(Morris EA. Diagnostic breast MR imaging: current status and future directions. Radiol Clin North Am 2007; 45: 863-880, vii., Kuhl C. The current status of breast MR imaging. Part I. Choice of technique, image interpretation, diagnostic accuracy, and transfer to clinical practice. Radiology 2007; 244: 356-378), and a recent study suggests that BPE is also a major breast cancer risk factor, possibly as important as, and independent of MD (King V, Brooks JD, Bernstein JL et al. BPE at breast MR imaging and breast cancer risk. Radiology 2011; 260: 50-60). BPE is much more sensitive to the effects of menopause and tamoxifen than is FGT (King V, Gu Y, Kaplan JB et al. Impact of menopausal status on BPE and fibroglandular tissue on breast MRI. Eur Radiol 2012; 22: 2641-2647, King V, Kaplan J, Pike MC et al. Impact of tamoxifen on amount of fibroglandular tissue, BPE, and cysts on breast MRI. Breast J 2012; 18: 527-534). Changes in MD and BPE may be most useful in predicting response to chemopreventive agents aimed at blocking breast cell proliferation. More study of the biological basis of the effects of MD and BPE is needed if we are to fully exploit these factors in developing chemopreventive approaches to breast cancer.

Background: This analysis was conducted to identify the participant characteristics associated with noncompliance in an oral contraceptive (OC) clinical trial.Study Design: We studied ovarian suppression among normal-weight and obese women during the use of levonorgestrel (LNG)-containing combination OCs. Participants underwent twice weekly phlebotomy during the study cycle and received up to $360 for participation. Along with other study assays, we analyzed 903 specimens from 181 women to measure LNG to assess OC compliance. Consistently undetectable LNG levels indicated noncompliance. To evaluate predictors of OC noncompliance during this study, we compared the characteristics of compliant and noncompliant participants using multivariable logistic regression. We assigned each participant to a relative poverty level based on US census data; all ether individual characteristics came directly from participant responses during the baseline interview.Results: One hundred eighty-one women completed the study; 31 were noncompliant (17%). In multivariable analyses, poverty level was the strongest predictor of noncompliance. Compared with those women in the quartile with the lowest level of residential poverty, other women were far more likely to be noncompliant, especially women in the quartile with the greatest prevalence of poverty (adjusted odds ratio, 8.4; 95% confidence interval, 1.5-46.1). Additional factors associated with noncompliance were education level less than a bachelor's degree and Hispanic ethnicity. Other demographic and psychometric measures were not associated with compliance.Conclusions: We found that noncompliance was strongly associated with residential poverty level, an indirect measure of individual income. In the United States, poverty is associated with female obesity, Hispanic ethnicity and low education, which were also associated here with noncompliance. Study compensation may motivate poor individuals to participate in clinical trials for income. Noncompliance in clinical trials, particularly differential noncompliance, jeopardizes study validity. (C) 2012 Elsevier Inc. All rights reserved.

We investigated the association between urinary tract infections (UTIs) and transitional cell carcinoma of the bladder in a population-based case–control study in Los Angeles covering 1586 cases and age-, gender-, and race-matched neighbourhood controls. A history of bladder infection was associated with a reduced risk of bladder cancer among women (odds ratio (OR), 0.66; 95% confidence interval (CI), 0.46–0.96). No effect was found in men, perhaps due to power limitations. A greater reduction in bladder cancer risk was observed among women with multiple infections (OR, 0.37; 95% CI, 0.18–0.78). Exclusion of subjects with a history of diabetes, kidney or bladder stones did not change the inverse association. A history of kidney infections was not associated with bladder cancer risk, but there was a weak association between a history of other UTIs and slightly increased risk among men. Our results suggest that a history of bladder infection is associated with a reduced risk of bladder cancer among women. Cytotoxicity from antibiotics commonly used to treat bladder infections is proposed as one possible explanation.

Low–moderate risk alleles that are relatively common in the population may explain a significant proportion of the excess familial risk of ovarian cancer (OC) not attributed to highly penetrant genes. In this study, we evaluated the risks of OC associated with common germline variants in five oncogenes ( BRAF , ERBB2 , KRAS , NMI and PIK3CA ) known to be involved in OC development. Thirty-four tagging SNPs in these genes were genotyped in ∼1800 invasive OC cases and 3000 controls from population-based studies in Denmark, the United Kingdom and the United States. We found no evidence of disease association for SNPs in BRAF , KRAS , ERBB2 and PIK3CA when OC was considered as a single disease phenotype; but after stratification by histological subtype, we found borderline evidence of association for SNPs in KRAS and BRAF with mucinous OC and in ERBB2 and PIK3CA with endometrioid OC. For NMI , we identified a SNP (rs11683487) that was associated with a decreased risk of OC (unadjusted P dominant =0.004). We then genotyped rs11683487 in another 1097 cases and 1792 controls from an additional three case–control studies from the United States. The combined odds ratio was 0.89 (95% confidence interval (CI): 0.80–0.99) and remained statistically significant ( P dominant =0.032). We also identified two haplotypes in ERBB2 associated with an increased OC risk ( P global =0.034) and a haplotype in BRAF that had a protective effect ( P global =0.005). In conclusion, these data provide borderline evidence of association for common allelic variation in the NMI with risk of epithelial OC.

Most of the early studies published on soy and breast cancer were not designed to test the effect of soy; the assessment of soy intake was usually crude and few potential confounders were considered in the analysis. In this review, we focused on studies with relatively complete assessment of dietary soy exposure in the targeted populations and appropriate consideration for potential confounders in the statistical analysis of study data. Meta-analysis of the 8 (1 cohort, 7 case–control) studies conducted in high-soy-consuming Asians show a significant trend of decreasing risk with increasing soy food intake. Compared to the lowest level of soy food intake (⩽5 mg isoflavones per day), risk was intermediate (OR=0.88, 95% confidence interval (CI)=0.78–0.98) among those with modest (∼10 mg isoflavones per day) intake and lowest (OR=0.71, 95% CI=0.60–0.85) among those with high intake (⩾20 mg isoflavones per day). In contrast, soy intake was unrelated to breast cancer risk in studies conducted in the 11 low-soy-consuming Western populations whose average highest and lowest soy isoflavone intake levels were around 0.8 and 0.15 mg per day, respectively. Thus, the evidence to date, based largely on case–control studies, suggest that soy food intake in the amount consumed in Asian populations may have protective effects against breast cancer.

Background Oral contraceptives were introduced almost 50 years ago, and over 100 million women currently use them. Oral contraceptives can reduce the risk of ovarian cancer, but the eventual public-health effects of this reduction will depend on how long the protection lasts after use ceases. We aimed to assess these effects.Methods Individual data for 23 257 women with ovarian cancer (cases) and 87 303 without ovarian cancer (controls) from 45 epidemiological studies in 21 countries were checked and analysed centrally. The relative risk of ovarian cancer in relation to oral contraceptive use was estimated, stratifying by study, age, parity, and hysterectomy.Findings Overall 7308 (31%) cases and 32 717 (37%) controls had ever used oral contraceptives, for average durations among users of 4 . 4 and 5 . 0 years, respectively. The median year of cancer diagnosis was 1993, when cases were aged an average of 56 years. The longer that women had used oral contraceptives, the greater the reduction in ovarian cancer risk (p<0. 0001). This reduction in risk persisted for more than 30 years after oral contraceptive use had ceased but became somewhat attenuated over time the proportional risk reductions per 5 years of use were 29% (95% CI 23-34%) for use that had ceased less than 10 years previously, 19% (14-24%) for use that had ceased 10-19 years previously, and 15% (9-21%) for use that had ceased 20-29 years previously. Use during the 1960s, 1970s, and 1980s was associated with similar proportional risk reductions, although typical oestrogen doses in the 1960s were more than double those in the 1980s. The incidence of mucinous tumours (12% of the total) seemed little affected by oral contraceptives, but otherwise the proportional risk reduction did not vary much between different histological types. In high-income countries, 10 years use of oral contraceptives was estimated to reduce ovarian cancer incidence before age 75 from 1 . 2 to 0 . 8 per 100 users and mortality from 0 . 7 to 0 . 5 per 100; for every 5000 woman-years of use, about two ovarian cancers and one death from the disease before age 75 are prevented.Interpretation Use of oral contraceptives confers long-term protection against ovarian cancer. These findings suggest that oral contraceptives have already prevented some 200000 ovarian cancers and 100000 deaths from the disease, and that over the next few decades the number of cancers prevented will rise to at least 30 000 per year.

There is evidence that progesterone plays a role in the aetiology of invasive epithelial ovarian cancer. Therefore, genes involved in pathways that regulate progesterone may be candidates for susceptibility to this disease. Previous studies have suggested that genetic variants in the progesterone receptor gene (PGR) may be associated with ovarian cancer risk, although results have been inconsistent. We have established an international consortium to pool resources and data from many ovarian cancer case–control studies in an effort to identify variants that influence risk. In this study, three PGR single nucleotide polymorphisms (SNPs), for which previous data have suggested they affect ovarian cancer risk, were examined. These were +331 C/T (rs10895068), PROGINS (rs1042838), and a 3′ variant (rs608995). A total of 4788 ovarian cancer cases and 7614 controls from 12 case–control studies were included in this analysis. Unconditional logistic regression was used to model the association between each SNP and ovarian cancer risk and two-sided P-values are reported. Overall, risk of ovarian cancer was not associated with any of the three variants studied. However, in histopathological subtype analyses, we found a statistically significant association between risk of endometrioid ovarian cancer and the PROGINS allele (n=651, OR=1.17, 95% CI=1.01–1.36, P=0.036). We also observed borderline evidence of an association between risk of endometrioid ovarian cancer and the +331C/T variant (n=725 cases; OR=0.80, 95% CI 0.62–1.04, P=0.100). These data suggest that while these three variants in the PGR are not associated with ovarian cancer overall, the PROGINS variant may play a modest role in risk of endometrioid ovarian cancer.

Obesity is associated with a decreased risk of breast cancer in premenopausal women but an increased risk in postmenopausal women, an effect that increases with time since menopause. Analysis of these effects of obesity shows that there is a ceiling to the carcinogenic effect of estrogen on the breast; increases in nonsex hormone-binding globulin-bound estradiol (non-SHBG bound E2) exceeding approximately 10.2 pg/ml have no further effect on breast cancer risk; this ceiling is lower than the lowest level seen during the menstrual cycle. This suggests that the effects of menopausal estrogen therapy (ET) and menopausal estrogen-progestin therapy (EPT) on a woman's breast cancer risk will greatly depend on her body mass index (BMI; weight in kilograms/height in meters squared, kg/m2) with the largest effects being in slender women. Epidemiological studies confirm this prediction. Our best estimates, per 5 years of use, of the effects of ET on breast cancer risk is a 30% increase in a woman with a BMI of 20 kg/m2 decreasing to an 8% increase in a woman with a BMI of 30 kg/m2; the equivalent figures for EPT are 50% and 26%. The analysis of the effects of estrogen also shows that even reducing the dose of estrogen in ET and EPT by as much as a half will have little or no effect on these risks. Reducing the progestin dose is likely to significantly reduce the risk of EPT: this is possible with an endometrial route of administration.

In vitro and in vivo studies have shown that cytochrome P450 3A4 (CYP3A4) is involved in the metabolism of oestrogens. There is evidence that grapefruit, an inhibitor of CYP3A4, increases plasma oestrogen concentrations. Since it is well established that oestrogen is associated with breast cancer risk, it is plausible that regular intake of grapefruit would increase a woman's risk of breast cancer. We investigated the association of grapefruit intake with breast cancer risk in the Hawaii-Los Angeles Multiethnic Cohort Study, a prospective cohort that includes over 50 000 postmenopausal women from five racial/ethnic groups. A total of 1657 incident breast cancer cases were available for analysis. Grapefruit intake was significantly associated with an increased risk of breast cancer (relative risk=1.30, 95% confidence interval 1.06-1.58) for subjects in the highest category of intake, that is, one-quarter grapefruit or more per day, compared to non-consumers (P(trend)=0.015). An increased risk of similar magnitude was seen in users of oestrogen therapy, users of oestrogen+progestin therapy, and among never users of hormone therapy. Grapefruit intake may increase the risk of breast cancer among postmenopausal women.

Active smoking has little or no effect on breast cancer risk but some investigators have suggested that passive smoking and its interaction with active smoking may be associated with an increased risk. In a population based case–control study of breast cancer in women aged 36–45 years at diagnosis, information on active smoking, passive smoking in the home, and other factors, was collected at interview from 639 cases and 640 controls. Women were categorised jointly by their active and passive smoking exposure. Among never smoking controls, women who also reported no passive smoking exposure were significantly more likely to be nulliparous and to be recent users of oral contraceptives. Among those never exposed to passive smoking, there was no significant association between active smoking and breast cancer, relative risk (RR) of 1.12 (95% confidence interval (CI) 0.72–1.73) for past smokers and RR of 1.19 (95% CI 0.72–1.95) for current smokers, nor was there an association with age started, duration or intensity of active smoking. Compared with women who were never active nor passive smokers, there was no significant association between passive smoking in the home and breast cancer risk in never smokers, RR of 0.89 (95% CI 0.64–1.25), in past smokers, RR of 1.09 (95% CI 0.75–1.56), or in current smokers, RR of 0.93 (95% CI 0.67–1.30). There was no trend with increasing duration of passive smoking and there was no heterogeneity among any of the subgroups examined. In this study, there was no evidence of an association between either active smoking or passive smoking in the home and risk of breast cancer.

Active smoking has little or no effect on breast cancer risk but some investigators have suggested that passive smoking and its interaction with active smoking may be associated with an increased risk. In a population based case - control study of breast cancer in women aged 36 - 45 years at diagnosis, information on active smoking, passive smoking in the home, and other factors, was collected at interview from 639 cases and 640 controls. Women were categorised jointly by their active and passive smoking exposure. Among never smoking controls, women who also reported no passive smoking exposure were significantly more likely to be nulliparous and to be recent users of oral contraceptives. Among those never exposed to passive smoking, there was no significant association between active smoking and breast cancer, relative risk ( RR) of 1.12 ( 95% confidence interval ( CI) 0.72 - 1.73) for past smokers and RR of 1.19 ( 95% CI 0.72 - 1.95) for current smokers, nor was there an association with age started, duration or intensity of active smoking. Compared with women who were never active nor passive smokers, there was no significant association between passive smoking in the home and breast cancer risk in never smokers, RR of 0.89 ( 95% CI 0.64 - 1.25), in past smokers, RR of 1.09 ( 95% CI 0.75 - 1.56), or in current smokers, RR of 0.93 ( 95% CI 0.67 - 1.30). There was no trend with increasing duration of passive smoking and there was no heterogeneity among any of the subgroups examined. In this study, there was no evidence of an association between either active smoking or passive smoking in the home and risk of breast cancer.

This study investigated dietary fiber intake in association with serum estrogen levels in naturally postmenopausal Latina women with a wide range of fiber intake. Estrone (E1), estradiol (E2), and sex-hormone-binding globulin (SHBG) were measured in 242 women. Associations between estrogen levels and intake of dietary fiber, including insoluble and soluble fractions, quantified from a food frequency questionnaire, were examined. The biomarker enterolactone was also measured. After adjustment for age, weight, and other nondietary factors, dietary fiber intake was inversely associated with E1 and E2; there was a 22% and 17% decrease (2Ptrend=0.023 and 0.045) among subjects in the highest quintile of intake compared with the lowest. Fitting dietary fiber together with soluble and insoluble nonstarch polysaccharides (NSP) showed a much greater decrease in E1 and E2 (47% and 41%, respectively) while increased soluble NSP intake showed increases in E1 and E2 (64% and 69%, respectively). Two foods, avocado and grapefruit, showed significant positive associations with E1 (2Ptrend=0.029 and 0.015, respectively). This study suggests that different components of dietary fiber may have very significant different effects on serum estrogen levels. The suggestive findings relating increased estrogen levels to avocado and grapefruit intakes need confirmation.

Controversy persists regarding the role of a low ratio of 2-hydroxyestone (2-OHE(1))/16alpha-hydroxyestrone (16alpha-OHE(1)) as a potential estrogen metabolism marker of increased risk for breast cancer. Most of the evidence has been provided by case-control studies, where tumor effects on hormone metabolism are not known. Studies in populations at various risk of breast cancer are not consistent, with some suggesting that levels of the ratio may be altered by changes in diet and exercise. We studied Asian American women participating as controls in a case-control study of breast cancer in which migration history--a composite of the subject's place of birth, type of residence in Asia (urban or rural), length of time living in the West, and grandparents' place of birth--was associated with a 6-fold risk gradient that paralleled the historical differences in incidence rates between the United States and Asian countries. This population offered the possibility to address whether the ratio of 2-OHE(1):16alpha-OHE(1) differs according to recognized breast cancer risk factors, including migration history. Overnight 12-hour urines were obtained from 368 premenopausal and 143 naturally postmenopausal women of Chinese, Japanese, or Filipino descent who donated urines between 1985 and 1988. The estrogen metabolites 2-OHE(1) and 16alpha-OHE(1) were measured with an ELISA kit and adjusted for creatinine levels. In each ethnic group, the ratio of 2-OHE(1):16alpha-OHE(1) was consistently lower in women born in the West than in those who had migrated from Asia. For premenopausal women, the ratio declined 20% due to lower levels of 2-OHE(1). Among postmenopausal women, the ratio was 23% lower in those born in the West, but no consistent patterns based on place of birth were observed for either 2-OHE(1) or 16alpha-OHE(1). The ratio did not vary with most recognized breast cancer risk factors, except for lower metabolite ratios in women with a younger age at first birth and more children, which runs contrary to the hypothesis, because both characteristics reduce breast cancer risk. Our study suggests that the ratio of 2-OHE(1):16alpha-OHE(1) may be a marker for lifestyle influences on estrogen metabolism associated with westernization.

BACKGROUNDLow intake of dietary fat and high intake of soy foods have been suggested to partly explain the lower breast cancer rates in Asia, perhaps because of lower endogenous estrogens.OBJECTIVEThe objective was to assess the hormonal and nonhormonal effects of diets resembling an Asian diet in terms of total fat and soy food contents.DESIGNFifty-seven postmenopausal women participated in a randomized, controlled, dietary intervention study. The subjects consumed a very-low-fat diet (VLFD; 11% of energy as fat), a Step I diet (25% of energy as fat) supplemented with soy food (SFD; 50 mg isoflavones/d), or a control Step I diet (CD; 27% of energy as fat) with no soy food. All diets were prepared at the General Clinical Research Center of the University of Southern California. Serum hormones and other markers were measured at baseline and every 2 wk during the 8 wk of intervention.RESULTSThere were no significant differences in total estradiol and sex hormone binding globulin at the completion of the intervention between women in the SFD and VLFD groups and those in the CD group. Serum insulin decreased significantly in the SFD group, and leptin decreased significantly in the SFD and VLFD groups; however, these changes did not differ significantly from the changes in the CD group.CONCLUSIONSThis study does not provide evidence that ingestion of soy food or a VLFD significantly reduces estrogen concentrations in postmenopausal women. However, short-term changes in diet may have significant and beneficial effects on blood insulin and leptin concentrations.