Associations between lifestyle, health, and clinical characteristics and circulating oxysterols and cholesterol precursors in women diagnosed with breast cancer: a cross-sectional study

Despite increasing evidence that cholesterol precursors and oxysterols, oxidized cholesterol metabolites, play a role in numerous pathological processes and diseases including breast cancer, little is known about correlates of these sterols in women with breast cancer. In this study, 2282 women with breast cancer and blood draw post diagnosis were included and cross-sectional associations between circulating levels of 15 sterols/oxysterols and (a) lifestyle, anthropometric, reproductive characteristics, (b) comorbidities and medication use, and (c) breast cancer tumor and treatment characteristics were calculated using generalized linear models. Obesity was strongly associated with circulating levels of 7-dehydrocholesterol (DC) (body mass index ≥ 30 vs. 18.5-24.9 kg/m2: 51.7% difference) and 7-ketocholesterol (KC) (40.0% difference). After adjustment for BMI, comorbidities such as cardiovascular disease were associated with higher levels of 7-DC (26.1% difference) and lower levels of desmosterol (- 16.4% difference). Breast cancer tumor characteristics including hormone receptor status, tumor stage, and endocrine therapy were associated with lanosterol, 24-DHLan, 7b-HC, and THC (e.g., THC; tumor stage IIIa vs. I: 36.9% difference). Weaker associations were observed for lifestyle characteristics and for any of the other oxysterols. The findings of this study suggest that cholesterol precursors are strongly associated with metabolic factors, while oxysterols are associated with breast cancer tumor characteristics, warranting further investigation into the role of cholesterol precursors and oxysterols in women with breast cancer and other populations.

Circulating oxysterols and prognosis among women with a breast cancer diagnosis: results from the MARIE patient cohort

BACKGROUND

Breast cancer is the most commonly diagnosed cancer in women worldwide, and underlying mechanistic pathways associated with breast cancer-specific and non-breast cancer-related deaths are of importance. Emerging evidence suggests a role of oxysterols, derivates of cholesterol, in multiple chronic diseases including breast cancer and coronary artery diseases. However, associations between oxysterols and survival have been minimally studied in women diagnosed with breast cancer. In this large breast cancer patient cohort, we evaluated associations between a panel of circulating oxysterols and mortality and recurrence outcomes.

METHODS

Concentrations of 13 circulating oxysterols representing different pathways of cholesterol metabolism were quantified using liquid-chromatography mass-spectrometry. Associations between baseline levels of oxysterols and cause-specific mortality outcomes and recurrence following a breast cancer diagnosis were assessed in 2282 women from the MARIE study over a median follow-up time of 11 years. We calculated hazard ratios (HR) and 95% confidence intervals (CI) using multivariable Cox proportional hazard models and competing risks models.

RESULTS

We observed no associations for circulating oxysterols and breast cancer-specific outcomes. Higher levels of six oxysterols were associated with an increased risk of cardiovascular disease death, including 24S-hydroxycholesterol (alternative bile acid pathway, HRlog2 = 1.73 (1.02, 2.93)), lanosterol (cholesterol biosynthesis pathway, HRlog2 = 1.95 (1.34, 2.83)), 7-ketocholesterol (HRlog2 = 1.26 (1.03, 1.55)), 5α,6α-epoxycholesterol (HRlog2 = 1.34 (1.02-1.77)), and 5a,6β-dihydroxycholestanol (HRlog2 = 1.34 (1.03, 1.76)). After adjusting for multiple comparisons, none of the associations were statistically significant.

CONCLUSION

We provide first evidence on a range of circulating oxysterols and mortality following a breast cancer diagnosis, contributing to a better understanding of associations between different pathways of cholesterol metabolism and prognosis in women with a breast cancer diagnosis. The findings of this study suggest circulating oxysterols may be associated with cardiovascular mortality among women diagnosed with breast cancer. Further studies are needed to evaluate these oxysterols as potential markers of risk for cardiovascular mortality among women with a breast cancer diagnosis as well as their clinical potential.

Endogenous estrogen receptor modulating oxysterols and breast cancer prognosis: Results from the MARIE patient cohort

BACKGROUND

27-hydroxycholesterol (HC) and 25-HC were identified as endogenous selective estrogen receptor modulators (SERMs) and estrogen receptor (ER) modulators, respectively. They are hypothesized to play a role in multiple physiologic processes and pathologies, including breast cancer development and progression.

METHODS

We evaluated circulating 27-HC and 25-HC, and outcomes following a breast cancer diagnosis in 2282 women from the MARIE study over median follow-up of 11.6 years. 27-HC and 25-HC were quantified by liquid chromatography-mass spectrometry. We calculated hazard ratios (HR) and 95% confidence intervals [CI] using multivariable Cox Proportional Hazards regression.

RESULTS

We observed no associations between 27-HC and breast cancer prognosis overall. Associations between 27-HC and survival differed by circulating estradiol concentrations and endocrine therapy, but not by hormone receptor status. Among women with estradiol levels below the median (0.08 nM), 27-HC was associated with higher risk of all-cause mortality (HRlog2 = 1.80 [1.20-2.71]) and breast cancer-specific mortality (HRlog2 = 1.95 [1.14-3.31]). No associations were observed in women with estradiol levels above the median. Higher 25-HC levels were associated with lower risk of recurrence (HRlog2 = 0.87 [0.77-0.98]).

CONCLUSION

Associations between 27-HC and breast cancer prognosis varied by circulating estradiol levels and endocrine therapy. Less consistent results were observed for 25-HC.

Characterization of ovarian cancer survival by histotype and stage: A nationwide study in Norway

Contemporary population-based data on ovarian cancer survival using current subtype classifications and by surgical status are sparse. We evaluated 1-, 3-, 5- and 7-year relative (and overall) survival, and excess hazards in patients with borderline tumors or invasive epithelial ovarian cancer diagnosed 2012 to 2021 in a nationwide registry-based cohort in Norway. Outcomes were evaluated by histotype, FIGO stage, cytoreduction surgery and residual disease. Overall survival was evaluated for non-epithelial ovarian cancer. Survival of women with borderline ovarian tumors was excellent (≥98.0% 7-year relative survival). Across all evaluated invasive epithelial ovarian cancer histotypes, 7-year relative survival for cases diagnosed with stages I or II disease was ≥78.3% (stage II high-grade serous). Survival for ovarian cancers diagnosed at stage ≥III differed substantially by histotype and time since diagnosis (eg, stage III, 5-year relative survival from 27.7% [carcinosarcomas] to 76.2% [endometrioid]). Overall survival for non-epithelial cases was good (91.8% 5-year overall survival). Women diagnosed with stage III or IV invasive epithelial ovarian cancer and with residual disease following cytoreduction surgery had substantially better survival than women not operated. These findings were robust to restriction to women with high reported functional status scores. Patterns for overall survival were similar to those for relative survival. We observed relatively good survival with early stage at diagnosis even for the high grade serous histotype. Survival for patients diagnosed at stage ≥III invasive epithelial ovarian cancer was poor for all but endometrioid disease. There remains an urgent need for strategies for risk reduction and earlier detection, together with effective targeted treatments.

In-depth evaluation of machine learning methods for semi-automating article screening in a systematic review of mechanistic literature

We aimed to evaluate the performance of supervised machine learning algorithms in predicting articles relevant for full-text review in a systematic review. Overall, 16,430 manually screened titles/abstracts, including 861 references identified relevant for full-text review were used for the analysis. Of these, 40% (n = 6573) were sub-divided for training (70%) and testing (30%) the algorithms. The remaining 60% (n = 9857) were used as a validation set. We evaluated down- and up-sampling methods and compared unigram, bigram, and singular value decomposition (SVD) approaches. For each approach, Naïve Bayes, Support Vector Machines (SVM), regularized logistic regressions, neural networks, random forest, Logit boost, and XGBoost were implemented using simple term frequency or Tf-Idf feature representations. Performance was evaluated using sensitivity, specificity, precision and area under the Curve. We combined predictions of the best-performing algorithms (Youden Index ≥0.3 with sensitivity/specificity≥70/60%). In a down-sample unigram approach, Naïve Bayes, SVM/quanteda text models with Tf-Idf, and linear SVM e1071 package with Tf-Idf achieved >90% sensitivity at specificity >65%. Combining the predictions of the 10 best-performing algorithms improved the performance to reach 95% sensitivity and 64% specificity in the validation set. Crude screening burden was reduced by 61% (5979) (adjusted: 80.3%) with 5% (27) false negativity rate. All the other approaches yielded relatively poorer performances. The down-sampling unigram approach achieved good performance in our data. Combining the predictions of algorithms improved sensitivity while screening burden was reduced by almost two-third. Implementing machine learning approaches in title/abstract screening should be investigated further toward refining these tools and automating their implementation.

Association of circulating free and total oxysterols in breast cancer patients

OBJECTIVES

Oxysterols, a family of oxidized cholesterol derivates, are of increasing interest due to their role in cancer development and progression. Some oxysterols are estrogen receptor modulators and thus of particular interest in breast cancer research. In human studies, two forms of circulating oxysterols are commonly evaluated: "free" (unesterified) and "total" (esterified and unesterified). However, associations between free and total oxysterols are not well established. We addressed this knowledge gap in a pilot study by evaluating correlations between the free and the total form of each of the circulating oxysterols (free vs. total), and pairwise associations within the panel of total oxysterols (total vs. total) and the panel of free oxysterols (free vs. free).

METHODS

Concentrations of oxysterols and other non-cholesterol sterols were quantified in blood samples of 27 breast cancer patients from the MARIE breast cancer patient cohort using liquid chromatography mass spectrometry. We used Spearman rank correlations to assess associations. Overall, 12 oxysterols (including 27-hydroxycholesterol (HC), 25-HC, 24S-HC, 7a-HC, 5a6a-epoxycholesterol) and five sterols (including lanosterol and desmosterol) were analyzed.

RESULTS

Strong correlations (r≥0.82) were observed for seven circulating free and total oxysterols/sterols. The free and total form of 27-HC (r=0.63), 25-HC (r=0.54), and two more oxysterols were weaker correlated. Correlation patterns in the panel of total oxysterols/sterols and the panel of free oxysterols/sterols were similar.

CONCLUSIONS

These findings demonstrate that concentrations of most free and total oxysterols/sterols are strongly correlated. We provide further insight into the interrelationships between oxysterols in breast cancer patients.

Physical activity and breast cancer survival: results from the Nurses' Health Studies

BACKGROUND

Physical activity is generally associated with better outcomes following diagnosis; however, few studies have evaluated change in pre- to postdiagnosis activity and repeated measures of activity by intensity and type.

METHODS

We evaluated physical activity and survival following a breast cancer diagnosis in the Nurses' Health Study and Nurses' Health Study II (n = 9308 women, n = 1973 deaths). Physical activity was evaluated as updated cumulative average of metabolic equivalent of task (MET)-h/wk (assigned per activity based on duration and intensity) and change in pre- to postdiagnosis activity. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

Higher postdiagnosis activity was inversely associated with breast cancer-specific mortality in categories from ≥9 MET-h/wk (vs <3 MET h/wk, HR≥9 to <18 = 0.74 [95% CI = 0.55 to 0.99]; HR≥27 = 0.69 [95% CI = 0.50 to 0.95]; Ptrend = .04) and all-cause mortality from ≥3 MET-h/wk (HR≥3 to <9 = 0.73 [95% CI = 0.61 to 0.88]; HR≥27 = 0.51 [95% CI = 0.41 to 0.63]; Ptrend < .001). Associations were predominantly observed for estrogen receptor-positive tumors and in postmenopausal women. Walking was associated with lower risk of all-cause mortality (≥9 vs <3 MET-h/wk, HR= 0.69 [95% CI = 0.57 to 0.84]) as was strength training. Relative to stable activity pre- to postdiagnosis (±3 MET-h/wk), increases from ≥3 to 9 MET-h/wk were associated with lower all-cause mortality risk (Ptrend < .001). Results were robust to adjustment for prediagnosis physical activity.

CONCLUSIONS

Physical activity was associated with lower risk of death following diagnosis. Increased pre- to postdiagnosis activity corresponding to at least 1-3 h/wk of walking was associated with lower risk of death. These results provide further impetus for women to increase their activity after a breast cancer diagnosis, though reverse causation cannot be fully excluded.

Prospective evaluation of 92 serum protein biomarkers for early detection of ovarian cancer

BACKGROUND

CA125 is the best available yet insufficiently sensitive biomarker for early detection of ovarian cancer. There is a need to identify novel biomarkers, which individually or in combination with CA125 can achieve adequate sensitivity and specificity for the detection of earlier-stage ovarian cancer.

METHODS

In the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, we measured serum levels of 92 preselected proteins for 91 women who had blood sampled ≤18 months prior to ovarian cancer diagnosis, and 182 matched controls. We evaluated the discriminatory performance of the proteins as potential early diagnostic biomarkers of ovarian cancer.

RESULTS

Nine of the 92 markers; CA125, HE4, FOLR1, KLK11, WISP1, MDK, CXCL13, MSLN and ADAM8 showed an area under the ROC curve (AUC) of ≥0.70 for discriminating between women diagnosed with ovarian cancer and women who remained cancer-free. All, except ADAM8, had shown at least equal discrimination in previous case-control comparisons. The discrimination of the biomarkers, however, was low for the lag-time of >9-18 months and paired combinations of CA125 with any of the 8 markers did not improve discrimination compared to CA125 alone.

CONCLUSION

Using pre-diagnostic serum samples, this study identified markers with good discrimination for the lag-time of 0-9 months. However, the discrimination was low in blood samples collected more than 9 months prior to diagnosis, and none of the markers showed major improvement in discrimination when added to CA125.

Endogenous Circulating Sex Hormone Concentrations and Colon Cancer Risk in Postmenopausal Women: A Prospective Study and Meta-Analysis

Background

Observational studies have consistently reported that postmenopausal hormone therapy use is associated with lower colon cancer risk, but epidemiologic studies examining the associations between circulating concentrations of endogenous estrogens and colorectal cancer have reported inconsistent results.

Methods

We investigated the associations between circulating concentrations of estrone, estradiol, free estradiol, testosterone, free testosterone, androstenedione, dehydroepiandrosterone (DHEA), progesterone, and sex hormone-binding globulin (SHBG) with colon cancer risk in a nested case-control study of 1028 postmenopausal European women (512 colon cancer cases, 516 matched controls) who were noncurrent users of exogenous hormones at blood collection. Multivariable conditional logistic regression models were used to compute odds ratios and 95% confidence intervals to evaluate the association between circulating sex hormones and colon cancer risk. We also conducted a dose-response meta-analysis of prospective studies of circulating estrone and estradiol with colorectal, colon, and rectal cancer risk in postmenopausal women. All statistical tests were 2-sided.

Results

In the multivariable model, a nonstatistically significantly positive relationship was found between circulating estrone and colon cancer risk (odds ratio per log2 1-unit increment = 1.17 [95% confidence interval = 1.00 to 1.38]; odds ratioquartile4-quartile1  = 1.33 [95% confidence interval = 0.89 to 1.97], P trend  = .20). Circulating concentrations of estradiol, free estradiol, testosterone, free testosterone, androstenedione, DHEA, progesterone, and SHBG were not associated with colon cancer risk. In the dose-response meta-analysis, no clear evidence of associations were found between circulating estradiol and estrone concentrations with colorectal, colon, and rectal cancer risk.

Conclusion

Our observational and meta-analysis results do not support an association between circulating concentrations of endogenous sex hormones and colon or rectal cancer in postmenopausal women.

Adiposity and Endometrial Cancer Risk in Postmenopausal Women: A Sequential Causal Mediation Analysis

BACKGROUND

Adiposity increases endometrial cancer risk, possibly through inflammation, hyperinsulinemia, and increasing estrogens. We aimed to quantify the mediating effects of adiponectin (anti-inflammatory adipocytokine); IL6, IL1-receptor antagonist, TNF receptor 1 and 2, and C-reactive protein (inflammatory status biomarkers); C-peptide (hyperinsulinemia biomarker); and free estradiol and estrone (estrogen biomarkers) in the adiposity-endometrial cancer link in postmenopausal women.

METHODS

We used data from a case-control study within the European Prospective Investigation into Cancer and Nutrition (EPIC). Eligible women did not have cancer, hysterectomy, and diabetes; did not use oral contraceptives or hormone therapy; and were postmenopausal at recruitment. Mediating pathways from adiposity to endometrial cancer were investigated by estimating natural indirect (NIE) and direct (NDE) effects using sequential mediation analysis.

RESULTS

The study included 163 cases and 306 controls. The adjusted OR for endometrial cancer for body mass index (BMI) ≥30 versus ≥18.5-<25 kg/m2 was 2.51 (95% confidence interval, 1.26-5.02). The ORsNIE were 1.95 (1.01-3.74) through all biomarkers [72% proportion mediated (PM)] decomposed as: 1.35 (1.06-1.73) through pathways originating with adiponectin (33% PM); 1.13 (0.71-1.80) through inflammation beyond (the potential influence of) adiponectin (13% PM); 1.05 (0.88-1.24) through C-peptide beyond adiponectin and inflammation (5% PM); and 1.22 (0.89-1.67) through estrogens beyond preceding biomarkers (21% PM). The ORNDE not through biomarkers was 1.29 (0.54-3.09). Waist circumference gave similar results.

CONCLUSIONS

Reduced adiponectin and increased inflammatory biomarkers, C-peptide, and estrogens mediated approximately 70% of increased odds of endometrial cancer in women with obesity versus normal weight.

IMPACT

If replicated, these results could have implications for identifying targets for intervention to reduce endometrial cancer risk in women with obesity.

Prognostic gene expression signature for high-grade serous ovarian cancer

BACKGROUND

Median overall survival (OS) for women with high-grade serous ovarian cancer (HGSOC) is ∼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.

Menstrual Factors, Reproductive History, Hormone Use, and Urothelial Carcinoma Risk: A Prospective Study in the EPIC Cohort

BACKGROUND

Urothelial carcinoma is the predominant (95%) bladder cancer subtype in industrialized nations. Animal and epidemiologic human studies suggest that hormonal factors may influence urothelial carcinoma risk.

METHODS

We used an analytic cohort of 333,919 women from the European Prospective Investigation into Cancer and Nutrition Cohort. Associations between hormonal factors and incident urothelial carcinoma (overall and by tumor grade, tumor aggressiveness, and non-muscle-invasive urothelial carcinoma) risk were evaluated using Cox proportional hazards models.

RESULTS

During a mean of 15 years of follow-up, 529 women developed urothelial carcinoma. In a model including number of full-term pregnancies (FTP), menopausal status, and menopausal hormone therapy (MHT), number of FTP was inversely associated with urothelial carcinoma risk (HR≥5vs1 = 0.48; 0.25-0.90; P trend in parous women = 0.010) and MHT use (compared with nonuse) was positively associated with urothelial carcinoma risk (HR = 1.27; 1.03-1.57), but no dose response by years of MHT use was observed. No modification of HRs by smoking status was observed. Finally, sensitivity analyses in never smokers showed similar HR patterns for the number of FTP, while no association between MHT use and urothelial carcinoma risk was observed. Association between MHT use and urothelial carcinoma risk remained significant only in current smokers. No heterogeneity of the risk estimations in the final model was observed by tumor aggressiveness or by tumor grade. A positive association between MTH use and non-muscle-invasive urothelial carcinoma risk was observed.

CONCLUSIONS

Our results support that increasing the number of FTP may reduce urothelial carcinoma risk.

IMPACT

More detailed studies on parity are needed to understand the possible effects of perinatal hormone changes in urothelial cells.

Adherence to the World Cancer Research Fund/American Institute for Cancer Research cancer prevention recommendations and risk of in situ breast cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort

BACKGROUND

Even though in situ breast cancer (BCIS) accounts for a large proportion of the breast cancers diagnosed, few studies have investigated potential risk factors for BCIS. Their results suggest that some established risk factors for invasive breast cancer have a similar impact on BCIS risk, but large population-based studies on lifestyle factors and BCIS risk are lacking. Thus, we investigated the association between lifestyle and BCIS risk within the European Prospective Investigation into Cancer and Nutrition cohort.

METHODS

Lifestyle was operationalized by a score reflecting the adherence to the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) cancer prevention recommendations. The recommendations utilized in these analyses were the ones pertinent to healthy body weight, physical activity, consumption of plant-based foods, energy-dense foods, red and processed meat, and sugary drinks and alcohol, as well as the recommendation on breastfeeding. Cox proportional hazards regression was used to assess the association between lifestyle score and BCIS risk. The results were presented as hazard ratios (HR) and corresponding 95% confidence intervals (CI).

RESULTS

After an overall median follow-up time of 14.9 years, 1277 BCIS cases were diagnosed. Greater adherence to the WCRF/AICR cancer prevention recommendations was not associated with BCIS risk (HR = 0.98, 95% CI 0.93-1.03; per one unit of increase; multivariable model). An inverse association between the lifestyle score and BCIS risk was observed in study centers, where participants were recruited mainly via mammographic screening and attended additional screening throughout follow-up (HR = 0.85, 95% CI 0.73-0.99), but not in the remaining ones (HR = 0.99, 95% CI 0.94-1.05).

CONCLUSIONS

While we did not observe an overall association between lifestyle and BCIS risk, our results indicate that lifestyle is associated with BCIS risk among women recruited via screening programs and with regular screening participation. This suggests that a true inverse association between lifestyle habits and BCIS risk in the overall cohort may have been masked by a lack of information on screening attendance. The potential inverse association between lifestyle and BCIS risk in our analyses is consistent with the inverse associations between lifestyle scores and breast cancer risk reported from previous studies.

Reproductive and Lifestyle Factors and Circulating sRANKL and OPG Concentrations in Women: Results from the EPIC Cohort

BACKGROUND

Except for a documented increase in osteoprotegerin (OPG) concentrations with older age, data on determinants of soluble Receptor Activator of Nuclear Factor κB (sRANKL) and OPG concentrations in women are limited. We evaluated reproductive and lifestyle factors as potential sources of variation in circulating sRANKL and OPG concentrations in pre- and postmenopausal women.

METHODS

This study includes 2,016 controls [n = 1,552 (76%) postmenopausal, n = 757 (38%) using postmenopausal hormone therapy (PMH)] from a breast cancer case-control study nested in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Serum sRANKL was measured using an ELISA and serum OPG using an electrochemiluminescent assay. Generalized linear models were used to evaluate associations between these analytes and reproductive and lifestyle factors.

RESULTS

Older age at blood collection was associated with lower sRANKL concentrations in postmenopausal women (P trend ≤ 0.03) and higher OPG concentrations in all women (P trend ≤ 0.01). Longer duration of oral contraceptive use among premenopausal women and postmenopausal PMH users was associated with higher OPG (P trend ≤ 0.04). In postmenopausal non-PMH users, sRANKL concentrations were lower with longer duration of oral contraceptive use and current (vs. never) smoking (P ≤ 0.01). sRANKL concentrations were higher among women with higher BMI (P trend ≤ 0.01). The evaluated factors accounted for 12% of the variation in sRANKL concentrations and 21% of the variation in OPG concentrations.

CONCLUSIONS

Circulating sRANKL and OPG concentrations are minimally impacted by hormone-related factors in pre- and postmenopausal women.

IMPACT

This study suggests circulating concentrations of sRANKL and OPG are unlikely to be strongly modified by hormone-related reproductive and lifestyle factors.

Abstract 601: Early pregnancy serum sRANKL, OPG, and TRAIL and maternal breast cancer risk: Results from the Finnish Maternity Cohort

The Receptor Activator of Nuclear Factor kappa-B (RANK)-axis mediates structural changes in the breast during pregnancy in preparation for lactation, but is also implicated in breast tumor development. The RANK-axis includes RANK, its ligand (RANKL) and osteoprotegerin (OPG). OPG is the decoy receptor for RANKL and Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL). Based results from experimental and epidemiologic studies, we hypothesized that relatively high serum concentrations of RANK-axis members in early pregnancy would be associated with higher risk of breast cancer in the mother, with differential effects in estrogen (ER)+ and progesterone receptor (PR)+ and ER-/PR- disease. A case-control study including 288 case-control sets (165 ER+/PR+, 79 ER-/PR-) was nested in the Finnish Maternity Cohort. Women eligible for this study donated a blood sample at age ≤40 years and ≤140 days gestation age (GA) in a primiparous term pregnancy; cases were diagnosed within 10 years of this pregnancy. Serum OPG and TRAIL were measured using an electrochemiluminescence assay, and sRANKL (soluble RANKL) using an enzyme-linked immunosorbent assay. Odds ratios (ORs) and 95% confidence intervals [CI] were calculated using conditional logistic regression adjusted for GA at blood collection. Relatively high sRANKL concentrations were associated with higher risk of ER+/PR+ breast cancer (Tertile3vs.1, OR=2.08 [1.25-3.44]) (Table); this association was similar after adjustment for OPG levels. sRANKL concentrations were not associated with ER-/PR- disease, and we observed no associations for OPG and TRAIL. In line with previous studies in non-pregnant women, we provide the first evidence for an association between early pregnancy sRANKL and risk of breast cancer in the decade following pregnancy. Relatively high circulating sRANKL concentrations in early pregnancy may identify women at increased risk of breast cancer subsequent to pregnancy.

Table.Serum concentrations of sRANKL, OPG and TRAIL in early pregnancy and breast cancer risk by ER/PR subtype: results from the Finnish Maternity Cohort.Tertiles123ptrendaORlog2phetbsRANKL, cut points (pmol/L)≤ .00050.005 - 0.09&gt; 0.09Full populationCases/Controls86/18199/181103/180288/542OR (95% CI)Ref.1.27 (0.88-1.83)1.42 (0.99-2.06)0.051.14 (1.00-1.29)0.36ER+/PR+Cases/Controls43/11461/10361/93165/310OR (95% CI)Ref.1.76 (1.08-2.88)2.08 (1.25-3.44)0.031.21 (1.02-1.44)ER-/PR-Cases/Controls27/4624/5228/5379/151OR (95% CI)Ref.0.89 (0.45-1.76)1.03 (0.52-2.06)0.451.09 (0.87-1.36)OPG, cut points (pmol/L)≤ 6.946.94 - 8.62&gt; 8.62Full populationCases/Controls c83/16773/166104/166260/499OR (95% CI)Ref.0.85 (0.57-1.26)1.21 (0.82-1.79)0.641.10 (0.73-1.65)0.99ER+/PR+Cases/Controls53/9842/9756/94151/289OR (95% CI)Ref.0.77 (0.46-1.28)1.08 (0.65-1.82)0.991.00 (0.58-1.70)ER-/PR-Cases/Controls19/4523/4129/5171/137OR (95% CI)Ref.1.36 (0.61-3.03)1.29 (0.60-2.77)0.950.98 (0.45-2.12)TRAIL, cut points (pmol/L)≤ 0.400.40 - 1.07&gt; 1.07Full populationCases/Controls c93/16679/16688/166258/492OR (95% CI)Ref.0.86 (0.59-1.26)0.93 (0.65-1.34)0.620.93 (0.71-1.22)0.74ER+/PR+Cases/Controls54/9542/9655/98150/285OR (95% CI)Ref.0.73 (0.44-1.21)0.94 (0.59-1.51)0.930.99 (0.70-1.40)ER-/PR-Cases/Controls24/4727/4720/4270/134OR (95% CI)Ref.1.09 (0.55-2.16)0.91 (0.45-1.84)0.690.90 (0.55-1.53)a ptrend based on log2-transformed sRANKL and OPG concentrations; b pheterogeneity comparing ER+/PR+ to ER-/PR- subtypes, based on log2-transformed sRANKL concentrations (244 case-sets); c 28 case sets (OPG) and 30 case sets (TRAIL) missing concentrations due to equipment failure.

Citation Format: Danja Sarink, Theron Johnson, Helja-Marja Surcel, Rudolf Kaaks, Renée Turzanski Fortner. Early pregnancy serum sRANKL, OPG, and TRAIL and maternal breast cancer risk: Results from the Finnish Maternity Cohort [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 601.

The role of plasma microseminoprotein-beta in prostate cancer: an observational nested case-control and Mendelian randomization study in the European prospective investigation into cancer and nutrition

BACKGROUND

Microseminoprotein-beta (MSP), a protein secreted by the prostate epithelium, may have a protective role in the development of prostate cancer. The only previous prospective study found a 2% reduced prostate cancer risk per unit increase in MSP. This work investigates the association of MSP with prostate cancer risk using observational and Mendelian randomization (MR) methods.

PATIENTS AND METHODS

A nested case-control study was conducted with the European Prospective Investigation into Cancer and Nutrition (EPIC) with 1871 cases and 1871 matched controls. Conditional logistic regression analysis was used to investigate the association of pre-diagnostic circulating MSP with risk of incident prostate cancer overall and by tumour subtype. EPIC-derived estimates were combined with published data to calculate an MR estimate using two-sample inverse-variance method.

RESULTS

Plasma MSP concentrations were inversely associated with prostate cancer risk after adjusting for total prostate-specific antigen concentration [odds ratio (OR) highest versus lowest fourth of MSP = 0.65, 95% confidence interval (CI) 0.51-0.84, Ptrend = 0.001]. No heterogeneity in this association was observed by tumour stage or histological grade. Plasma MSP concentrations were 66% lower in rs10993994 TT compared with CC homozygotes (per allele difference in MSP: 6.09 ng/ml, 95% CI 5.56-6.61, r2=0.42). MR analyses supported a potentially causal protective association of MSP with prostate cancer risk (OR per 1 ng/ml increase in MSP for MR: 0.96, 95% CI 0.95-0.97 versus EPIC observational: 0.98, 95% CI 0.97-0.99). Limitations include lack of complete tumour subtype information and more complete information on the biological function of MSP.

CONCLUSIONS

In this large prospective European study and using MR analyses, men with high circulating MSP concentration have a lower risk of prostate cancer. MSP may play a causally protective role in prostate cancer.

Nonsteroidal anti-inflammatory drug use and breast cancer risk in a European prospective cohort study

Experimental studies have shown a protective effect of nonsteroidal anti-inflammatory drugs (NSAIDs) on breast cancer development. However, results from epidemiological cohort studies are less consistent. Our objective was to assess the association between NSAID use and breast cancer risk within the European Prospective Investigation into Cancer and Nutrition (EPIC). EPIC is a prospective cohort study initiated in 1992 in 10 European countries. Self-reported information on NSAID use at baseline has been collected in five EPIC countries. Multivariable Cox regression models were used to estimate hazard ratios for the association of NSAID use with breast cancer incidence with adjustment for potential confounders. We also assessed effect modification by breast cancer risk factors and examined the associations within specific breast cancer subtypes. Among the 140,981 women included in the analysis, 7% were regularly using NSAIDs at baseline. During a median follow-up time period of 13 years, 7,379 incident breast cancer cases were diagnosed (816 in situ and 6,563 invasive). There were no statistically significant associations between NSAID use and breast cancer risk, overall and by subtypes. However, a statistically significant interaction was observed for invasive cases between NSAID use and ever use of menopausal hormonal therapy (MHT) among postmenopausal women [MHT users: HRNSAID use  = 0.84 (0.73-0.96); non MHT users: HRNSAID use  = 1.08 (0.93-1.25); pinteraction  = 0.05]. Our results indicate potential effect modification of MHT use on the association between use of NSAIDs and breast cancer risk which deserves in-depth investigation in studies with accurate data on both NSAID and MHT use.

Tumor-associated autoantibodies as early detection markers for ovarian cancer? A prospective evaluation

Immuno-proteomic screening has identified several tumor-associated autoantibodies (AAb) that may have diagnostic capacity for invasive epithelial ovarian cancer, with AAbs to P53 proteins and cancer-testis antigens (CTAGs) as prominent examples. However, the early detection potential of these AAbs has been insufficiently explored in prospective studies. We performed ELISA measurements of AAbs to CTAG1A, CTAG2, P53 and NUDT11 proteins, for 194 patients with ovarian cancer and 705 matched controls from the European EPIC cohort, using serum samples collected up to 36 months prior to diagnosis under usual care. CA125 was measured using electrochemo-luminiscence. Diagnostic discrimination statistics were calculated by strata of lead-time between blood collection and diagnosis. With lead times ≤6 months, ovarian cancer detection sensitivity at 0.98 specificity (SE98) varied from 0.19 [95% CI 0.08-0.40] for CTAG1A, CTAG2 and NUDT1 to 0.23 [0.10-0.44] for P53 (0.33 [0.11-0.68] for high-grade serous tumors). However, at longer lead-times, the ability of these AAb markers to distinguish future ovarian cancer cases from controls declined rapidly; at lead times >1 year, SE98 estimates were close to zero (all invasive cases, range: 0.01-0.11). Compared to CA125 alone, combined logistic regression scores of AAbs and CA125 did not improve detection sensitivity at equal level of specificity. The added value of these selected AAbs as markers for ovarian cancer beyond CA125 for early detection is therefore limited.

Obesity as risk factor for subtypes of breast cancer: results from a prospective cohort study

BACKGROUND

Earlier epidemiological studies indicate that associations between obesity and breast cancer risk may not only depend on menopausal status and use of exogenous hormones, but might also differ by tumor subtype. Here, we evaluated whether obesity is differentially associated with the risk of breast tumor subtypes, as defined by 6 immunohistochemical markers (ER, PR, HER2, Ki67, Bcl-2 and p53, separately and combined), in the prospective EPIC-Germany Study (n = 27,012).

METHODS

Formalin-fixed and paraffin-embedded (FFPE) tumor tissues of 657 incident breast cancer cases were used for histopathological analyses. Associations between BMI and breast cancer risk across subtypes were evaluated by multivariable Cox regression models stratified by menopausal status and hormone therapy (HT) use.

RESULTS

Among postmenopausal non-users of HT, higher BMI was significantly associated with an increased risk of less aggressive, i.e. ER+, PR+, HER2-, Ki67_low, Bcl-2+ and p53- tumors (HR per 5 kg/m²: 1.44 [1.10, 1.90], p = 0.009), but not with risk of more aggressive tumor subtypes. Among postmenopausal users of HT, BMI was significantly inversely associated with less aggressive tumors (HR per 5 kg/m²: 0.68 [0.50, 0.94], p = 0.018). Finally, among pre- and perimenopausal women, Cox regression models did not reveal significant linear associations between BMI and risk of any tumor subtype, although analyses by BMI tertiles showed a significantly lower risk of less aggressive tumors for women in the highest tertile (HR: 0.55 [0.33, 0.93]).

CONCLUSION

Overall, our results suggest that obesity is related to risk of breast tumors with lower aggressiveness, a finding that requires replication in larger-scale analyses of pooled prospective data.

Alcohol consumption and risk of urothelial cell bladder cancer in the European prospective investigation into cancer and nutrition cohort

Findings on the association between alcohol consumption and bladder cancer are inconsistent. We investigated that association in the European Prospective Investigation into Cancer and Nutrition cohort. We included 476,160 individuals mostly aged 35-70 years, enrolled in ten countries and followed for 13.9 years on average. Hazard ratios (HR) for developing urothelial cell carcinoma (UCC; 1,802 incident cases) were calculated using Cox proportional hazards models. Alcohol consumption at baseline and over the life course was analyzed, as well as different types of beverages (beer, wine, spirits). Baseline alcohol intake was associated with a statistically nonsignificant increased risk of UCC (HR 1.03; 95% confidence interval (CI) 1.00-1.06 for each additional 12 g/day). HR in smokers was 1.04 (95% CI 1.01-1.07). Men reporting high baseline intakes of alcohol (>96 g/day) had an increased risk of UCC (HR 1.57; 95% CI 1.03-2.40) compared to those reporting moderate intakes (<6 g/day), but no dose-response relationship emerged. In men, an increased risk of aggressive forms of UCC was observed even at lower doses (>6 to 24 g/day). Average lifelong alcohol intake was not associated with the risk of UCC, however intakes of spirits > 24 g/day were associated with an increased risk of UCC in men (1.38; 95% CI 1.01-1.91) and smokers (1.39; 95% CI 1.01-1.92), compared to moderate intakes. We found no association between alcohol and UCC in women and never smokers. In conclusion, we observed some associations between alcohol and UCC in men and in smokers, possibly because of residual confounding by tobacco smoking.

Systematic review: Tumor-associated antigen autoantibodies and ovarian cancer early detection

OBJECTIVES

Tumor-associated autoantibodies (AAbs), produced as an immune response to tumor-associated antigens (TAAs), are a novel pathway of early detection markers.

METHODS

We conducted a systematic review on AAbs and ovarian cancer to summarize the diagnostic performance of individual AAbs and AAb panels. A total of 29 studies including 85 AAbs were included; 27 of the studies were conducted in prevalent cases and cancer-free controls and 2 investigations included pre-diagnosis samples. The majority of studies were hypothesis-driven, evaluating AAbs to target TAAs; 10 studies used screening approaches such as serological expression cloning (SEREX) and nucleic acid-programmable protein arrays (NAPPA).

RESULTS

The highest sensitivities for individual AAbs were reported for RhoGDI-AAbs (89.5%) and TUBA1C-AAbs (89%); however, specificity levels were relatively low (80% and 75%, respectively). High sensitivities at high specificities were reported for HOXA7-AAbs for detection of moderately differentiated ovarian tumors (66.7% sensitivity at 100% specificity) and IL8-AAbs in stage I-II ovarian cancer (65.5% sensitivity at 98% specificity). A panel of 11 AAbs (ICAM3, CTAG2, p53, STYXL1, PVR, POMC, NUDT11, TRIM39, UHMK1, KSR1, and NXF3) provided 45% sensitivity at 98% specificity for serous ovarian cancer, when at least 2 AAbs were above a threshold of 95% specificity. Twelve of the AAbs identified in this review were investigated in more than one study. Data on diagnostic discrimination by tumor histology and stage at diagnosis are sparse. Limited data suggest select AAb markers improve diagnostic discrimination when combined with markers such as CA125 and HE4.

CONCLUSIONS

AAbs for ovarian cancer early detection is an emerging area, and large-scale, prospective investigations considering histology and stage are required for discovery and validation. However, data to date suggests panels of AAbs may eventually reach sufficient diagnostic discrimination to allow earlier detection of disease as a complement to existing markers and transvaginal ultrasound.

A Comparative Study on the WCRF International/University of Bristol Methodology for Systematic Reviews of Mechanisms Underpinning Exposure-Cancer Associations

The World Cancer Research Fund (WCRF) International and the University of Bristol have developed a novel framework for providing an overview of mechanistic pathways and conducting a systematic literature review of the biologically plausible mechanisms underlying exposure-cancer associations. Two teams independently applied the two-stage framework on mechanisms underpinning the association between body fatness and breast cancer to test the framework feasibility and reproducibility as part of a WCRF-commissioned validation study. In stage I, a "hypothesis-free" approach was used to provide an overview of potential intermediate mechanisms between body fatness and breast cancer. Dissimilar rankings of potential mechanisms were observed between the two teams due to different applications of the framework. In stage II, a systematic review was conducted on the insulin-like growth factor 1 receptor (IGF1R) chosen as an intermediate mechanism. Although the studies included differed, both teams found inconclusive evidence for the body fatness-IGF1R association and modest evidence linking IGF1R to breast cancer, and therefore concluded that there is currently weak evidence for IGF1R as mechanism linking body fatness to breast cancer. The framework is a good starting point for conducting systematic reviews by integrating evidence from mechanistic studies on exposure-cancer associations. On the basis of our experience, we provide recommendations for future users. Cancer Epidemiol Biomarkers Prev; 26(11); 1583-94. ©2017 AACR.

Biomarkers of folate and vitamin B12 and breast cancer risk: report from the EPIC cohort

Epidemiological studies have reported inconsistent findings for the association between B vitamins and breast cancer (BC) risk. We investigated the relationship between biomarkers of folate and vitamin B12 and the risk of BC in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Plasma concentrations of folate and vitamin B12 were determined in 2,491 BC cases individually matched to 2,521 controls among women who provided baseline blood samples. Multivariable logistic regression models were used to estimate odds ratios by quartiles of either plasma B vitamin. Subgroup analyses by menopausal status, hormone receptor status of breast tumors (estrogen receptor [ER], progesterone receptor [PR] and human epidermal growth factor receptor 2 [HER2]), alcohol intake and MTHFR polymorphisms (677C > T and 1298A > C) were also performed. Plasma levels of folate and vitamin B12 were not significantly associated with the overall risk of BC or by hormone receptor status. A marginally positive association was found between vitamin B12 status and BC risk in women consuming above the median level of alcohol (ORQ4-Q1  = 1.26; 95% CI 1.00-1.58; Ptrend  = 0.05). Vitamin B12 status was also positively associated with BC risk in women with plasma folate levels below the median value (ORQ4-Q1  = 1.29; 95% CI 1.02-1.62; Ptrend  = 0.03). Overall, folate and vitamin B12 status was not clearly associated with BC risk in this prospective cohort study. However, potential interactions between vitamin B12 and alcohol or folate on the risk of BC deserve further investigation.

An epidemiologic risk prediction model for ovarian cancer in Europe: the EPIC study

BACKGROUND

Ovarian cancer has a high case-fatality ratio, largely due to late diagnosis. Epidemiologic risk prediction models could help identify women at increased risk who may benefit from targeted prevention measures, such as screening or chemopreventive agents.

METHODS

We built an ovarian cancer risk prediction model with epidemiologic risk factors from 202,206 women in the European Prospective Investigation into Cancer and Nutrition study.

RESULTS

Older age at menopause, longer duration of hormone replacement therapy, and higher body mass index were included as increasing ovarian cancer risk, whereas unilateral ovariectomy, longer duration of oral contraceptive use, and higher number of full-term pregnancies were decreasing risk. The discriminatory power (overall concordance index) of this model, as examined with five-fold cross-validation, was 0.64 (95% confidence interval (CI): 0.57, 0.70). The ratio of the expected to observed number of ovarian cancer cases occurring in the first 5 years of follow-up was 0.90 (293 out of 324, 95% CI: 0.81-1.01), in general there was no evidence for miscalibration.

CONCLUSION

Our ovarian cancer risk model containing only epidemiological data showed modest discriminatory power for a Western European population. Future studies should consider adding informative biomarkers to possibly improve the predictive ability of the model.

Human papillomavirus antibodies and future risk of anogenital cancer: a nested case-control study in the European prospective investigation into cancer and nutrition study

PURPOSE

Human papillomavirus (HPV) type 16 (HPV16) causes cancer at several anatomic sites. In the European Prospective Investigation Into Cancer and Nutrition study, HPV16 E6 seropositivity was present more than 10 years before oropharyngeal cancer diagnosis and was nearly absent in controls. The current study sought to evaluate the extent to which HPV16 E6 antibodies are present before diagnosis of anogenital cancers within the same cohort.

METHODS

Four hundred incident anogenital cancers (273 cervical, 24 anal, 67 vulvar, 12 vaginal, and 24 penile cancers) with prediagnostic blood samples (collected on average 3 and 8 years before diagnosis for cervix and noncervix cancers, respectively) and 718 matched controls were included. Plasma was analyzed for antibodies against HPV16 E6 and multiple other HPV proteins and genotypes and evaluated in relation to risk using unconditional logistic regression.

RESULTS

HPV16 E6 seropositivity was present in 29.2% of individuals (seven of 24 individuals) who later developed anal cancer compared with 0.6% of controls (four of 718 controls) who remained cancer free (odds ratio [OR], 75.9; 95% CI, 17.9 to 321). HPV16 E6 seropositivity was less common for cancers of the cervix (3.3%), vagina (8.3%), vulva (1.5%), and penis (8.3%). No associations were seen for non-type 16 HPV E6 antibodies, apart from anti-HPV58 E6 and anal cancer (OR, 6.8; 95% CI, 1.4 to 33.1). HPV16 E6 seropositivity tended to increase in blood samples drawn closer in time to cancer diagnosis.

CONCLUSION

HPV16 E6 seropositivity is relatively common before diagnosis of anal cancer but rare for other HPV-related anogenital cancers.

Insulin-like growth factor I and risk of epithelial invasive ovarian cancer by tumour characteristics: results from the EPIC cohort

BACKGROUND

Prospective studies on insulin-like growth factor I (IGF-I) and epithelial ovarian cancer (EOC) risk are inconclusive. Data suggest risk associations vary by tumour characteristics.

METHODS

We conducted a nested case-control study in the European Prospective Investigation into Cancer and Nutrition (EPIC) to evaluate IGF-I concentrations and EOC risk by tumour characteristics (n=565 cases). Multivariable conditional logistic regression models were used to estimate associations.

RESULTS

We observed no association between IGF-I and EOC overall or by tumour characteristics.

CONCLUSIONS

In the largest prospective study to date was no association between IGF-I and EOC risk. Pre-diagnostic serum IGF-I concentrations may not influence EOC risk.

Dietary intake of acrylamide and endometrial cancer risk in the European Prospective Investigation into Cancer and Nutrition cohort

BACKGROUND

Three prospective studies have evaluated the association between dietary acrylamide intake and endometrial cancer (EC) risk with inconsistent results. The objective of this study was to evaluate the association between acrylamide intake and EC risk: for overall EC, for type-I EC, and in never smokers and never users of oral contraceptives (OCs). Smoking is a source of acrylamide, and OC use is a protective factor for EC risk.

METHODS

Cox regression was used to estimate hazard ratios (HRs) for the association between acrylamide intake and EC risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Acrylamide intake was estimated from the EU acrylamide monitoring database, which was matched with EPIC questionnaire-based food consumption data. Acrylamide intake was energy adjusted using the residual method.

RESULTS

No associations were observed between acrylamide intake and overall EC (n=1382) or type-I EC risk (n=627). We observed increasing relative risks for type-I EC with increasing acrylamide intake among women who both never smoked and were non-users of OCs (HRQ5vsQ1: 1.97, 95% CI: 1.08-3.62; likelihood ratio test (LRT) P-value: 0.01, n=203).

CONCLUSIONS

Dietary intake of acrylamide was not associated with overall or type-I EC risk; however, positive associations with type I were observed in women who were both non-users of OCs and never smokers.

Early pregnancy sex steroids and maternal risk of epithelial ovarian cancer

Well-established associations between reproductive characteristics and epithelial ovarian cancer (EOC) support an involvement of sex steroid hormones in the etiology of EOC. Limited previous studies have evaluated circulating androgens and the risk of EOC, and estrogens and progesterone have been investigated in only one of the previous studies. Furthermore, there is little data on potential heterogeneity in the association between circulating hormones and EOC by histological subgroup. Therefore, we conducted a nested case-control study within the Finnish Maternity Cohort and the Northern Sweden Maternity Cohort to investigate the associations between circulating pre-diagnostic sex steroid concentrations and the histological subtypes of EOC. We identified 1052 EOC cases among cohort members diagnosed after recruitment (1975-2008) and before March 2011. Up to three controls were individually matched to each case (n=2694). Testosterone, androstenedione, 17-hydroxyprogesterone (17-OHP), progesterone, estradiol (E2), and sex hormone-binding globulin levels were measured in serum samples collected during the last pregnancy before EOC diagnosis. We used conditional logistic regression to estimate odds ratios (ORs) and 95% CIs. Associations between hormones and EOC differed with respect to tumor histology and invasiveness. Sex steroid concentrations were not associated with invasive serous tumors; however, doubling of testosterone and 17-OHP concentration was associated with approximately 40% increased risk of borderline serous tumors. A doubling of androgen concentrations was associated with a 50% increased risk of mucinous tumors. The risk of endometrioid tumors increased with higher E2 concentrations (OR: 1.89 (1.20-2.98)). This large prospective study in pregnant women supports a role of sex steroid hormones in the etiology of EOC arising in the ovaries.

Sex hormones and risk of breast cancer in premenopausal women: a collaborative reanalysis of individual participant data from seven prospective studies

BACKGROUND

Associations between circulating concentrations of oestrogens, progesterone, and androgens with breast cancer and related risk factors in premenopausal women are not well understood. We aimed to characterise these associations with a pooled analysis of data from seven studies.

METHODS

Individual participant data for prediagnostic sex hormone and sex hormone-binding globulin (SHBG) concentrations were contributed from seven prospective studies. We restricted analyses to women who were premenopausal and younger than 50 years at blood collection, and to women with breast cancer diagnosed before age 50 years. We estimated odds ratios (ORs) with 95% CIs for breast cancer associated with hormone concentrations by conditional logistic regression in cases and controls matched for age, date of blood collection, and day of cycle, with stratification by study and further adjustment for cycle phase. We examined associations of hormones with risk factors for breast cancer in control women by comparing geometric mean hormone concentrations in categories of these risk factors, adjusted for study, age, phase of menstrual cycle, and body-mass index (BMI). All statistical tests were two-sided.

FINDINGS

We included data for up to 767 women with breast cancer and 1699 controls in the risk analyses. Breast cancer risk was associated with a doubling in concentrations of oestradiol (OR 1·19, 95% CI 1·06-1·35), calculated free oestradiol (1·17, 1·03-1·33), oestrone (1·27, 1·05-1·54), androstenedione (1·30, 1·10-1·55), dehydroepiandrosterone sulphate (1·17, 1·04-1·32), testosterone (1·18, 1·03-1·35), and calculated free testosterone (1·08, 0·97-1·21). Breast cancer risk was not associated with luteal phase progesterone (doubling in concentration OR 1·00, 95% CI 0·92-1·09), and adjustment for other factors had little effect on any of these ORs. Cross-sectional analyses in control women showed several associations of sex hormones with breast cancer risk factors.

INTERPRETATION

Circulating oestrogens and androgens are positively associated with the risk for breast cancer in premenopausal women.

A prospective cohort study of modifiable risk factors for gestational diabetes among Hispanic women: design and baseline characteristics

OBJECTIVES

Women diagnosed with gestational diabetes mellitus (GDM) are at high risk for future diabetes, with rates of GDM consistently higher in Hispanic than non-Hispanic white women. Currently recognized risk factors for GDM are absent in up to half of affected women, and studies addressing modifiable risk factors for GDM in Hispanic women are sparse.

METHODS

Proyecto Buena Salud is an ongoing prospective cohort study of Hispanic women in Massachusetts designed to assess physical activity, psychosocial stress, and GDM risk. Bilingual interviewers recruit prenatal care patients early in pregnancy and assess activity, trait anxiety, perceived stress, and depressive symptoms using validated questionnaires.

RESULTS

Baseline characteristics of the first 632 participants are presented. Women were predominantly young (69% <24 years), were unmarried (87%), and had low levels of education (48% had less than high school). Women with high acculturation were less likely to live with a partner (OR: 0.6, 95% CI 0.4-0.8) than women with low acculturation. Few participants met physical activity guidelines during pregnancy (5.2%). Levels of perceived stress (mean 26.9 +/- 7.1), trait anxiety (mean 41.6 +/- 10.4), and depressive symptoms (33.2%) were high.

CONCLUSIONS

Proyecto Buena Salud represents a high-risk population of pregnant Hispanic women who are predominantly inactive, with higher levels of perceived stress, trait anxiety, and depressive symptoms compared to predominantly non-Hispanic white cohorts studied earlier. Therefore, Proyecto Buena Salud provides a unique opportunity to prospectively evaluate modifiable risk factors for GDM. Findings will inform prenatal behavioral intervention programs designed to address modifiable GDM risk factors.

Risk factors for prenatal depressive symptoms among Hispanic women

Prior studies of risk factors for depressive symptoms during pregnancy are sparse and the majority have focused on non-Hispanic white women. Hispanics are the largest minority group in the US and have the highest birth rates. We examined associations between pre and early pregnancy factors and depressive symptoms in early pregnancy among 921 participants in Proyecto Buena Salud, an ongoing cohort of pregnant Puerto Rican and Dominican women in Western Massachusetts. Depressive symptoms were assessed by the Edinburgh Postnatal Depression Scale (mean=13 weeks gestation) by bilingual interviewers who also collected data on sociodemographic, acculturation, behavioral, and psychosocial factors. A total of 30% of participants were classified as having depressive symptoms (EPDS scores>12) with mean+SD scores of 9.28+5.99. Higher levels of education (college/graduate school vs. <high school: RR=0.60, 95% CI 0.41-0.86), household income (Ptrend=0.02), and living with a spouse/partner (0.80; 95% CI 0.63-1.00) were independently associated with lower risk of depressive symptoms. There was the suggestion that failure to discontinue cigarette smoking with the onset of pregnancy (RR=1.32; 95% CI 0.97-1.71) and English language preference (RR=1.33; 95% CI 0.96-1.70) were associated with higher risk. Single marital status, second generation in the U.S., and higher levels of alcohol consumption were associated with higher risk of depressive symptoms in univariate analyses, but were attenuated after adjustment for other risk factors. Findings in the largest, fastest-growing ethnic minority group can inform intervention studies targeting Hispanic women at risk of depression in pregnancy.

Prepregnancy body mass index, gestational weight gain, and risk of hypertensive pregnancy among Latina women

OBJECTIVE

Prepregnancy body mass index (BMI) and gestational weight gain have been associated with hypertensive disorders of pregnancy, but previous studies have included few Latinas, a group at increased risk.

STUDY DESIGN

We examined these associations in the Latina Gestational Diabetes Mellitus Study, a prospective cohort of 1231 women conducted from 2000 to 2004.

RESULTS

In multivariable analysis, obese women (BMI > 29.0 kg/m(2)) had 2.5 times the risk of hypertensive pregnancy (95% confidence interval [CI], 1.3-4.8) and 2.7 times the risk of preeclampsia (95% CI, 1.2-5.8), compared with women whose BMI was 19.8 to 26.0 kg/m(2). Women with excessive gestational weight gain had a 3-fold increased risk of a hypertensive disorder of pregnancy (95% CI, 1.1-7.2) and a 4-fold risk of preeclampsia (95% CI, 1.2-14.5), compared with women achieving weight gain guidelines.

CONCLUSION

These findings suggest prepregnancy obesity and excessive weight gain are associated with hypertension in pregnancy in a Latina population and could be potentially modifiable risk factors.

Smoking and risk of preterm birth among predominantly Puerto Rican women

PURPOSE

Studies of smoking during pregnancy and preterm birth among Hispanic women are sparse. Our goal was to evaluate the effect of cigarette smoking during pre-pregnancy, early pregnancy, and mid pregnancy on preterm birth among Hispanic women, the fastest growing ethnic group in the United States.

METHODS

We evaluated data from a prospective cohort study of 1,041 Hispanic (predominantly Puerto Rican) women recruited between 2000 and 2004 in Springfield, Massachusetts. At recruitment (mean = 15 weeks), women reported their smoking since pregnancy awareness (early pregnancy) and in the year prior to pregnancy (pre-pregnancy). Mid pregnancy smoking was collected at a second interview (mean = 28 weeks).

RESULTS

Smoking in pre-pregnancy was not associated with preterm birth. After adjustment for age, parity, education, and illicit drug use, women who smoked in early pregnancy had 1.6 times the risk of preterm birth (95% confidence interval [CI], 1.0-2.7) compared with nonsmokers. Women who smoked in mid pregnancy had 2.1 times the risk of preterm birth (95% CI, 1.0-4.2) compared with nonsmokers with a trend of increased risk of preterm birth with increasing levels of smoking (p trend, 0.03).

CONCLUSIONS

Smoking in early or mid pregnancy increased the risk of spontaneous preterm birth in a Hispanic population.