Search

BackgroundResults from randomized trials indicate that treatment with tamoxifen or chemotherapy for primary breast cancer reduces the risk for contralateral breast cancer. However, less is known about how long the risk is reduced and the impact of factors such as age and menopausal status.MethodsThe study included 634 women with contralateral breast cancer (case patients) and 1158 women with unilateral breast cancer (control subjects) from the Women's Environment, Cancer and Radiation Epidemiology Study. The women were younger than age 55 when they were first diagnosed with breast cancer during 1985-1999. Rate ratios (RRs) and 95% confidence intervals (CIs) for contralateral breast cancer after treatment with chemotherapy or tamoxifen were assessed by multivariable adjusted conditional logistic regression analyses.ResultsChemotherapy was associated with a lower risk for contralateral breast cancer (RR = 0.57, 95% CI = 0.42 to 0.75) than no chemotherapy. A statistically significant association between chemotherapy and reduced risk for contralateral breast cancer persisted up to 10 years after the first breast cancer diagnosis and was stronger among women who became postmenopausal within 1 year of the first breast cancer diagnosis (RR = 0.28, 95% CI = 0.11 to 0.76). Tamoxifen use was also associated with reduced risk for contralateral breast cancer (RR = 0.66, 95% CI = 0.50 to 0.88) compared with no use, and the association was statistically significant for 5 years after the first diagnosis.ConclusionThe associations between chemotherapy and tamoxifen treatment and reduced risk for contralateral breast cancer appear to continue for 10 and 5 years, respectively, after the initial breast cancer is diagnosed. Ovarian suppression may have a role in the association between chemotherapy and reduced risk for contralateral breast cancer.

Alcohol intake may be one of the few modifiable risk factors for breast cancer. In a prospective cohort of 29,875 women with 423 cases of breast cancer during 1993-2000, we examined the relationship between postmenopausal breast cancer incidence rate and alcohol consumption in different life periods. When alcohol intake during four age ranges, twenties, thirties, forties and fifties was evaluated, only the intake in the fifties increased the risk of breast cancer [rate ratio (RR) = 1.12 (95% CI: 1.05-1.19)] per 10 g/d increase in alcohol intake. After adjustment for intake at study entry, this association was no longer present [RR = 1.01 (95% CI: 0.91-1.13)]. The cumulative lifetime alcohol intake, adjusted for recent intake, showed no association with postmenopausal breast cancer risk. Recent alcohol intake, adjusted for the alcohol intake in the other life time periods, showed a significant association of RR = 1.09 (95% CI: 1.00-1.18) per 10 g/d. There was no indication of a higher risk among women with early drinking start, nor did women who started to drink before their first birth have a higher risk than women who started to drink later in life. Our results suggest that baseline intake of alcohol is a more important determinant of postmenopausal breast cancer risk than earlier lifetime exposure. KEY WORDS: * alcohol intake * lifetime * breast cancer

The association between oophorectomy and risk of breast cancer in the general population is uncertain. The aim of our study was to determine the breast cancer rate in women from the general population after oophorectomy (performed before/after menopause), and whether this varies by use of hormone replacement therapy (HRT), hysterectomy, body mass index (BMI) and shift work. The study included 24 409 female nurses (aged ≥45 years) participating in the Danish Nurse Cohort. Nurses were followed from cohort entry until date of breast cancer, death, emigration or end of follow‐up at 31 December 2018, whichever came first. Poisson regression with log‐transformed person‐years as the offset examined the association between oophorectomy and breast cancer (all ages and stratified by menopausal status at time of oophorectomy). The potential modifying effect of HRT use, hysterectomy, BMI and shift work on the associations was estimated. During 502 463 person‐years of follow‐up, 1975 (8.1%) nurses were diagnosed with breast cancer. Bilateral oophorectomy was associated with a reduced breast cancer rate compared to nurses with preserved ovaries, adjusted rate ratio (95% confidence interval): 0.79 (0.64; 0.99). Similar associations (magnitude and direction) were detected for unilateral oophorectomy and when stratifying according to menopausal status at time of oophorectomy, but without statistical significance. Unilateral and bilateral oophorectomy is associated with a reduced breast cancer rate in women from the general population. This association is not modified by use of HRT, hysterectomy, BMI or shift work. What's new? While the consensus from studies in the general population indicates that bilateral oophorectomy reduces breast cancer risk, none have investigated whether hormone replacement therapy, hysterectomy, body mass index, or shift work modify this association. This large prospective study of Danish female nurses found that both unilateral and bilateral oophorectomy reduced breast cancer rate, although this association was only statistically significant for bilateral oophorectomy. Neither hysterectomy, shift work, nor body mass index modified the effect of bilateral oophorectomy on breast cancer rate. Use of hormone replacement therapy did not modify the association between bilateral oophorectomy and breast cancer rate. [ABSTRACT FROM AUTHOR]

The association between pre-diagnostic alcohol consumption and breast cancer recurrence and breast cancer specific mortality was investigated in 1,052 women diagnosed with early breast cancer in a prospective cohort of 29,875 women. Known clinical, lifestyle and socioeconomic risk factors were evaluated and adjusted for in multivariate analysis. We found a modest but significant association between pre-diagnostic alcohol consumption and breast cancer recurrence with a median follow-up of six years after date of diagnosis, both when using baseline measures of alcohol intake (HR, 1.65; 95% CI, 1.02-2.67; >2 units/day vs. ≤1 unit/day) and cumulated alcohol intake (HR, 2.02; 95% CI, 1.06-3.85; >40 drinking years vs. 0

Abstract: Acrylamide is a probable human carcinogen, with industrial contact, tobacco smoking and foods processed at high temperatures as the main routes of exposure. In animal studies oral intake of acrylamide has been related to cancer development, with indications that the increased cancer occurrence especially regards endocrine related tumors. In human epidemiological studies, dietary exposure to acrylamide has also been suggested related to higher risk of endocrine related tumors, like estrogen sensitive breast cancer. The aim of the present study was to evaluate if pre-diagnostic acrylamide exposure, measured by acrylamide and glycidamide hemoglobin adducts (AA-Hb and GA-Hb), were associated to mortality in breast cancer cases. Among 24,697 postmenopausal women included into a Danish cohort between 1993 and 1997, 420 developed breast cancer before 2001 and 110 died before 2009. AA-Hb and GA-Hb concentrations measured in blood samples were related to mortality by Cox proportional hazard models. Estimates are given per 25pmol/g globin higher levels. Among non-smokers, higher concentrations of GA-Hb were associated to a higher hazard rate of breast cancer specific mortality (HR (95% CI): 1.63 (1.06–2.51)), the hazard rate among women diagnosed with estrogen receptor positive tumors was (HR (95% CI): 2.23 (1.38–3.61)). For AA-Hb the tendency was similar, but only statistically significant among those with estrogen receptor positive tumors (HR (95% CI): 1.31 (1.02–1.69)). In conclusion, the present study indicates that pre-diagnostic exposure to acrylamide may be related to mortality among breast cancer patients and that this may especially concern the most endocrine related type of breast cancer. [Copyright &y& Elsevier]

Objective: Rehabilitation programmes are intended to help cancer patients achieve optimal functioning and live independently. We evaluated whether a psychosocial rehabilitation course was effective in relieving cancer patients' distress and improving their well-being. Methods: Patients with breast, prostate or colorectal cancer diagnosed within 2 years who had finished primary treatment were randomised to usual care or a 6-day residential course of lectures, discussions and peer groups on issues related to treatment and living with cancer. Changes in self-reported distress (POMS-Sf) and quality of life (EORTC QLQ-C30) from baseline to 1 and 6 months' follow-up were measured. Analyses were adjusted for baseline scores of outcome, cancer site, time since diagnosis, gender, age and education. Results: Of 507 patients, 452 were included in the analyses, 404 completed the 1-month and 394 the 6-month assessment. Patients in the control group showed greater decreases in total mood disturbance and subscales of the POMS-Sf and showed more improvement in emotional, cognitive and social functioning at both 1 and 6 months and in role functioning at 6 months than the intervention group. A similar pattern was observed in analyses of breast cancer patients only. Conclusion: A 6-day residential rehabilitation course did not relieve cancer patients' distress or improve their well-being. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective: The aim of this prospective cohort study was to identify factors associated with fatigue in women with breast cancer who attended a 6-day rehabilitation course. Furthermore, to investigate level of fatigue 1 year after the rehabilitation course, after accounting for baseline fatigue levels. Methods: Between 2002 and 2005 we included 775 women with breast cancer and measured fatigue, emotional functioning and insomnia using the EORTC subscales and sociodemographics from a baseline questionnaire prior to participation in the rehabilitation course. Information on disease-specific and treatment factors was obtained from a nationwide clinical database. From the 12-month follow-up questionnaire we obtained level of fatigue. We estimated the influence of factors on the relative risk for a 10-points increase in fatigue score in generalised linear models. For the analysis of fatigue at 12 months follow-up we added fatigue level at baseline and relapse since baseline. Results: Higher tumour grade and insomnia predicted higher levels of fatigue, whereas better emotional functioning was associated with lower levels. After 12 months of follow-up fatigue levels were associated with level at baseline and with emotional functioning, insomnia, relapse and being on sick leave or unemployed. Emotional level, insomnia and high grade were associated with level of fatigue. After 1 year, a high level at baseline, insomnia and low emotional functioning was associated with greater fatigue. Conclusions: These longitudinal results support that cancer-related fatigue can be a persistent phenomenon and that focus on psychological distress and sleeping problems might be beneficial in these women. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Although many case-control studies have suggested positive associations between carbohydrate intake and breast cancer incidence rates in both pre- and postmenopausal women, there is limited information available from cohort studies. We examined the effect of the intake of different carbohydrates, the glycemic index, and the glycemic load on breast cancer incidence in postmenopausal women taking into consideration tumor estrogen receptor status. Postmenopausal women (n = 23,870; aged 50-65 y) participated in the "Diet, Cancer, and Health" study, and provided information about diet and established risk factors for breast cancer. During follow-up, we identified 634 incidents of breast cancer. Associations between carbohydrate intake and breast cancer incidence were analyzed using Cox's regression models. There was no association for intake of glucose, fructose, sucrose, maltose, lactose, or starch and breast cancer incidence rate, and no association for glycemic index or glycemic load after adjusting for confounding factors. Intake of different carbohydrates was not associated with breast cancer incidence rates for either estrogen receptor positive (ER+) or (ER-) breast cancer. Similarly, glycemic index and glycemic load were not associated with ER+ breast cancer after adjusting for confounding factors. A borderline significant positive association between glycemic index and (ER-) breast cancer was observed (P = 0.05). In conclusion, we found no clear associations between intake of different carbohydrates, total carbohydrate intake, glycemic index, or glycemic load and breast cancer incidence in postmenopausal women. Furthermore, when ER+ and ER- breast cancer cases were analyzed separately, no clear associations were observed. [ABSTRACT FROM AUTHOR]

The mammalian lignan enterolactone (ENL), which is produced from dietary plant-lignan precursors by the intestinal microflora, may protect against breast cancer and other hormone-dependent cancers. This cross-sectional study examined which variables related to diet and lifestyle were associated with high plasma concentrations of ENL in Danish postmenopausal women. Plasma ENL was measured by time-resolved fluoroimmunoassay in 857 Danish women aged 50-64 y who participated in a prospective cohort study. Diet was assessed using a semiquantitative FFQ, and background information on lifestyle was collected using a self-administered questionnaire. Multiple analyses of covariance were completed in two steps. The median plasma ENL concentration was 27 nmol/L (range 0-455 nmol/L). In covariance analyses, positive associations were found between consumption of cereals, vegetables, and beverages and plasma ENL concentration. When analyzing subgroups of these food groups, the associations were confined to whole-grain products, cabbage, leafy vegetables, and coffee. For fat and the nondietary variables, negative associations between BMI, smoking, and frequency of bowel movements and plasma ENL concentration were observed. These data show that foods high in ENL precursors are associated with high concentrations of ENL. Furthermore, smoking, frequent bowel movements, and consumption of fat seems to have a negative affect on the ENL concentration. In conclusion, whole grains and vegetables are the most important dietary providers of plant lignans for the concentration of ENL in Danish postmenopausal women, and if ENL is found to protect against cancer or heart disease, the intake of whole grains and vegetables should be increased. [ABSTRACT FROM AUTHOR]

Animal studies have, in general, been supportive of a protective effect of fish and fish (n-3) PUFA against breast cancer risk; but the epidemiologic evidence of such a relationship is limited. Case-control and cohort studies have rarely shown significant associations. The association between total fish intake and the effect of fat content and preparation method of the fish, in relation to the incidence rate ratios of breast cancer, were investigated among postmenopausal women. We also investigated the effect of fish intake with respect to estrogen receptor expression of breast cancer tumors. A total of 23,693 postmenopausal women from the prospective study "Diet, Cancer and Health" were included in the study. During follow-up, 424 women were diagnosed with breast cancer. The incidence rate ratio (IRR) and 95% CI per each additional 25 g of mean daily intake of fish were 1.13 (CI, 1.03-1.23). Analysis of fatty fish gave IRR of 1.11 (CI, 0.91-1.34), and the result for lean fish was 1.13 (CI, 0.99-1.29). When fish intake was stratified into three types of preparation methods, the IRR for fried fish was 1.09 (CI, 0.95-1.25), for boiled fish 1.09 (CI, 0.85-1.42), and for processed fish 1.12 (CI, 0.93-1.34). The IRR per additional 25 g of mean daily intake of fish was 1.14 (CI, 1.03-1.26) for estrogen receptor-positive (ER+) and 1.00 (CI, 0.81-1.24) for estrogen receptor-negative (ER-) breast cancer. In conclusion, this study showed that higher intakes of fish were significantly associated with higher incidence rates of breast cancer. The association was present only for development of ER+ breast cancer. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To test the effectiveness of a psycho-educational group intervention to improve psychological distress measured by POMS TMD, Quality of Life measured by European Organisation for Research and Treatment of Cancer (EORTC), the core and breast cancer module, Mental Adjustment measured by MAC and marital relationship measured by BLRI in women with primary breast cancer conducted 10weeks after surgery. A secondary outcome was 4-year survival. Patients and methods: We randomly assigned 210 patients with primary breast cancer to a control or an intervention group. Patients in the intervention group were offered two weekly 6-h sessions of psycho-education and eight weekly 2-h sessions of group psychotherapy. All participants were followed up for Quality of Life, coping ability and social relations 1, 6 and 12months after the intervention and on survival 4years after surgical treatment. Results: No statistically significant effects of the intervention were found on any of the psychosocial questionnaire outcomes. There were not enough cases of death to analyse overall survival. The only statistically significant result was for patients who used anti depressive medication, for whom almost all measures improved over time, in both the control and intervention groups. Conclusion: Psycho-education and group psychotherapy did not decrease psychological distress or increase Quality of Life, Mental Adjustment or improve marital relationship among patients with primary breast cancer. [Copyright &y& Elsevier]

Abstract: Alcohol is a risk factor for breast cancer. We wanted to determine if ADH polymorphisms which modify the rate of ethanol oxidation to acetaldehyde, were associated with breast cancer risk. We matched 809 postmenopausal breast cancer cases with 809 controls, nested within the prospective Diet, Cancer and Health study. Among variant allele carriers of ADH1C Arg272Gln, alcohol intake increased the risk of breast cancer with 14% (95% CI: 1.04–1.24) per 10g alcohol/day, but not among homozygous wild type carriers (p for interaction=0.06). Thus, slow oxidation of ethanol seemed to be associated with breast cancer risk. [Copyright &y& Elsevier]

Abstract: Alcohol is a risk factor for postmenopausal breast cancer. One of several proposed mechanisms is that alcohol-related breast cancer is caused by increased sex hormone levels. PPARγ inhibits aromatase transcription in breast adipocytes. We reproduced previously found allele-specific effects of the wildtype Pro-allele of PPARG Pro12Ala in alcohol related breast cancer. In transiently transfected cells, transcriptional activation by PPARγ and the PPARγ-PGC-1α complex was inhibited by ethanol. PPARγ 12Ala-mediated transcription activation was not enhanced by PGC-1α, resulting in allele-specific transcription activation by the PPARγ 12Pro-PGC-1α complex. Our results suggest that PPARγ and PGC-1α activity is an important determinant of alcohol related breast cancer. [Copyright &y& Elsevier]

Abstract: Background: In Denmark, the incidence of breast cancer is higher among women with higher socioeconomic position. We investigated whether differences in exposure to certain risk factors contribute to this gradient, as measured from education, income and occupation. Methods: We conducted a cohort study of 23111 postmenopausal women aged 50–65 years who were enrolled in the prospective Danish ‘Diet, Cancer and Health’ study between 1993 and 1995. At baseline, all women filled in a questionnaire on lifestyle and food frequency. The results were analysed in Cox proportional hazard models. Results: Part of the association with socioeconomic position is due to the potential mediators reproductive pattern, use of hormone replacement therapy and alcohol consumption. After simultaneous adjustment for these factors, the hazard ratios were 1.06 (95% confidence interval [CI], 0.88–1.27) for women with higher education and 1.07 (95% CI, 0.85–1.34) for women with higher income. The HR ratio for women working as higher officials when compared with unskilled workers was 1.23 (0.96–1.59). Conclusion: The results support the hypothesis that the higher incidence of breast cancer among socially advantaged women is mediated partly by differences in exposure to reproductive factors, hormone replacement therapy and alcohol. [Copyright &y& Elsevier]