The influence of metabolic factors and ethnicity on breast cancer risk, treatment and survival: The Oslo ethnic breast cancer study.

Background: Breast cancer risk remains higher in high-income compared with low-income countries. However, it is unclear to what degree metabolic factors influence breast cancer development in women 30 years after immigration from low- to a high-incidence country.

Methods: Using Cox regression models, we studied the association between pre-diagnostic metabolic factors and breast cancer development, and whether this association varied by ethnicity among 13,802 women participating in the population-based Oslo Ethnic Breast Cancer Study.

Effects of a 1-Year Physical Activity Intervention on Markers of Hemostasis among Breast Cancer Survivors: A Randomized Controlled Trial.

 Physical activity may reduce the development of breast cancer. Whereas hypercoagulability has been linked to adverse outcomes in breast cancer patients, the effects of physical activity on their hemostatic factors are unknown. The study aimed to assess whether long-term (1 year) physical activity can affect hemostatic factors in breast cancer patients.

Dietary changes in early-stage breast cancer patients from pre-surgery and over the 12 months post-surgery.

The time after a breast cancer diagnosis is a potential period for making positive dietary changes, but previous results are conflicting. The main aim of the present study was to study breast cancer patients' dietary changes during the 12 months post-surgery and from 12 months pre-surgery to 12 months post-surgery with repeated administration of a 7-d pre-coded food diary and an FFQ, respectively. Women (n 506), mean age 55·3 years diagnosed with invasive breast cancer (stages I and II), were included.

Exploring the effects of lifestyle on breast cancer risk, age at diagnosis, and survival: the EBBA-Life study.

Purpose: Whether an unfavorable lifestyle not only affects breast cancer risk, but also influences age at onset of breast cancer and survival, is under debate.

Methods: In a population-based cohort, the Energy Balance and Breast Cancer Aspects throughout life (EBBA-Life) study, a total of 17,145 women were included. During follow-up, 574 women developed invasive breast cancer.

Metabolite and lipoprotein responses and prediction of weight gain during breast cancer treatment.

Background: Breast cancer treatment has metabolic side effects, potentially affecting risk of cardiovascular disease (CVD) and recurrence. We aimed to compare alterations in serum metabolites and lipoproteins during treatment between recipients and non-recipients of chemotherapy, and describe metabolite profiles associated with treatment-related weight gain.

Methods: This pilot study includes 60 stage I/II breast cancer patients who underwent surgery and were treated according to national guidelines.

Validation of repeated self-reported n-3 PUFA intake using serum phospholipid fatty acids as a biomarker in breast cancer patients during treatment.

Background: The role of n-3 polyunsaturated fatty acids (PUFAs) in breast cancer is not clear and under debate. To explore this relationship it is important to have proper validated dietary assessment methods for measuring the intake of n-3 PUFAs. The aim of the current study is to validate two different methods used to assess the intake of selected n-3 PUFAs as well as food sources of long-chained n-3 PUFAs.

Impact of pre-diagnostic triglycerides and HDL-cholesterol on breast cancer recurrence and survival by breast cancer subtypes.

Background: High triglycerides and low levels of high density lipoprotein (HDL)-cholesterol are observed to promote tumor growth. However, whether breast cancer heterogeneity may explain the contradictory influence of triglycerides and cholesterol observed on breast cancer prognosis remains unclear.

Methods: A population-based survival study among 464 breast cancer cases identified within the Tromsø study was conducted.

Erratum: Inflammation of mammary adipose tissue occurs in overweight and obese patients exhibiting early-stage breast cancer.

[This corrects the article DOI: 10.1038/s41523-017-0015-9.].

Inflammation of mammary adipose tissue occurs in overweight and obese patients exhibiting early-stage breast cancer.

Growing evidence indicates that adiposity is associated with breast cancer risk and negatively affects breast cancer recurrence and survival, a paracrine role of mammary adipose tissue being very likely in this process. In contrast to other adipose depots, occurrence of a sub-inflammatory state of mammary adipose tissue defined by dying adipocytes surrounded by macrophages forming crown-like structures in overweight and obese subjects, remains only partially described. In a general population of breast cancer patients (107 patients) mostly undergoing breast-conserving surgery, we found a positive association between patient's body composition, breast adipocytes size, and presence of crown-like structures in mammary adipose tissue close to the tumor.

Lipoprotein subfractions by nuclear magnetic resonance are associated with tumor characteristics in breast cancer.

Background: High-Density Lipoprotein (HDL)-cholesterol, has been associated with breast cancer development, but the association is under debate, and whether lipoprotein subfractions is associated with breast tumor characteristics remains unclear.

Methods: Among 56 women with newly diagnosed invasive breast cancer stage I/II, aged 35-75 years, pre-surgery overnight fasting serum concentrations of lipids were assessed, and body mass index (BMI) was measured. All breast tumors were immunohistochemically examined in the surgical specimen.

Alcohol consumption, endogenous estrogen and mammographic density among premenopausal women.

Introduction: Alcohol consumption may promote aromatization of androgens to estrogens, which may partly explain the observations linking alcohol consumption to higher breast cancer risk. Whether alcohol consumption is associated with endogenous estrogen levels, and mammographic density phenotypes in premenopausal women remains unclear.

Methods: Alcohol consumption was collected by self-report and interview, using semi quantitative food frequency questionnaires, and a food diary during seven days of a menstrual cycle among 202 premenopausal women, participating in the Energy Balance and Breast Cancer Aspects (EBBA) study I.

High-density lipoprotein-cholesterol, daily estradiol and progesterone, and mammographic density phenotypes in premenopausal women.

High-density lipoprotein-cholesterol (HDL-C) may influence the proliferation of breast tumor cells, but it is unclear whether low HDL-C levels, alone or in combination with cyclic estrogen and progesterone, are associated with mammographic density, a strong predictor of breast cancer development. Fasting morning serum concentrations of HDL-C were assessed in 202 premenopausal women, 25 to 35 years of age, participating in the Norwegian Energy Balance and Breast Cancer Aspects (EBBA) I study. Estrogen and progesterone were measured both in serum, and daily in saliva, throughout an entire menstrual cycle.

Women who are married or living as married have higher salivary estradiol and progesterone than unmarried women.

Objectives: Extensive research has demonstrated that marriage and parenting are associated with lower testosterone levels in men, however, very little is known about associations with hormone concentrations in women. Two studies have found lower testosterone in relation to pair-bonding and motherhood in women, with several others suggesting that estradiol levels are lower among parous women than nulliparous women. Here, we examine estradiol and progesterone concentrations in relation to marriage and motherhood in naturally cycling, reproductive age women.

Perfluoroalkyl substances and ovarian hormone concentrations in naturally cycling women.

Objective: To examine associations between environmental exposure to perfluoroalkyl substances (PFASs) and ovarian hormone concentrations in naturally cycling women.

Design: E2 and P were measured in saliva samples collected daily for a single menstrual cycle and concentrations of PFASs (including perfluoroctane sulfonate [PFOS] and perfluoroctanoic acid) were measured in serum samples collected during the same cycle.

Setting: Not applicable.

Cyclic endogenous estrogen and progesterone vary by mammographic density phenotypes in premenopausal women.

Estrogen and progesterone are key factors in the development of breast cancer, but it remains unclear whether these hormones are associated with mammographic density phenotypes in premenopausal women. We measured percent mammographic density, nondense area, and absolute mammographic density using computer-assisted breast density readings (Madena) from digitized mammograms taken on a scheduled day of the menstrual cycle (day 7-12) among 202 healthy, premenopausal women (Energy Balance and Breast cancer Aspects Study-I). Daily salivary concentrations of 17β-estradiol and progesterone throughout an entire menstrual cycle and fasting morning serum concentrations of hormones on 3 specific days of the menstrual cycle were assessed.

Gene variations in oestrogen pathways, CYP19A1, daily 17β-estradiol and mammographic density phenotypes in premenopausal women.

Introduction: High mammographic density is an established breast cancer risk factor, and circulating oestrogen influences oestrogen-regulating gene expression in breast cancer development. However, less is known about the interrelationships of common variants in the CYP19A1 gene, daily levels of oestrogens, mammographic density phenotypes and body mass index (BMI) in premenopausal women.

Methods: Based on plausible biological mechanisms related to the oestrogen pathway, we investigated the association of single nucleotide polymorphisms (SNPs) in CYP19A1, 17β-estradiol and mammographic density in 202 premenopausal women.

Insulin-like growth factor-1, growth hormone, and daily cycling estrogen are associated with mammographic density in premenopausal women.

Background: Mammographic density represents epithelial and stromal proliferation, while insulin-like growth factor (IGF)-1, insulin-like growth factor-binding protein-3, growth hormone (GH), and estrogen may influence cellular proliferation. However, whether these growth factors independently, or in combination with estrogen, influence mammographic density in premenopausal women remains unclear.

Materials And Methods: Growth factors were assessed in 202 ovulating premenopausal women participating in the Energy Balance and Breast Cancer Aspects-I study.

[Musculoskeletal disease and sick-leave].

Background: Complaints due to the musculoskeletal system comprise the largest group of diagnoses associated with annual sick payment. We have studied how musculoskeletal complaints predict prolonged sick-leave in a normal population in general and after adjusting for individual confounding factors in the age-group from 40 to 50 years.

Material And Methods: The study is based on information from 14 058 women and men aged 40 - 45 years, who participated in the Hordaland Health Study (HUSK) 1997 - 1999.