Alcohol, tobacco and breast cancer--collaborative reanalysis of individual data from 53 epidemiological studies, including 58,515 women with breast cancer and 95,067 women without the disease

Self-affirmation and the biased processing of threatening health-risk information

Self-affirming before reading about the link between alcohol and breast cancer promoted increased message acceptance among young women at higher risk. Differences were maintained on variables measured up to 1 month later. Relative to their nonaffirmed counterparts, higher risk, self-affirmed participants had higher ratings of risk, imagination, intention to reduce alcohol consumption, and negative affect, such as fear, while reading the leaflet. In contrast, there were no differences between the groups on measures of broader message acceptance (belief in the link, evidence strength). Thus, self-affirmation promoted acceptance of the personal relevance of the message, a critical step in the precaution adoption process. Overall, the findings support the view that self-affirmation in an unrelated domain can offset defensive processing of a threatening health message, promoting central route persuasion and producing consequential and durable increases in message acceptance.

ADH3 genotype, alcohol intake and breast cancer risk

Moderate alcohol consumption of approximately 1-2 drinks per day has been associated with a 30-50% increase in breast cancer risk. Individuals differ in their ability to metabolize alcohol through genetic differences in alcohol dehydrogenase (ADH), the enzyme that catalyzes the oxidation of approximately 80% of ethanol to acetaldehyde, a known carcinogen. Individuals differ in their ADH genotype, and one locus in particular (ADH3) is polymorphic in Caucasian populations. Using data from the Long Island Breast Cancer Study Project, we examined whether fast metabolizers of alcohol, as measured by the ADH3(1-1) genotype, have a higher risk of breast cancer from alcohol intake compared with those individuals who are slow metabolizers, but consume similar amounts of alcohol. We combined genotyping information with questionnaire data on 1047 breast cancer cases and 1101 controls and used unconditional logistic regression methods to estimate multivariate-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) between alcohol intake and breast cancer risk. Among individuals homozygous for the fast metabolizing allele (ADH(3)1-1), a lifetime alcohol consumption of 15-30 g/day (approximately 1-2 drinks per day) increased breast cancer risk by 2-fold (OR=2.0, 95% CI=1.1-3.5). In contrast, the increase in risk from a lifetime alcohol consumption of 15-30 g/day was less pronounced in the intermediate and slow metabolizing groups, respectively: ADH3(1-2) (OR=1.5, 95% CI 0.9-2.4) and ADH(3)2-2 (OR=1.3, 95% CI 0.5-3.5). Fast metabolizers who drank 15-30 g/day of alcohol had 2.3 times (95% CI 1.3-4.0) greater risk of breast cancer than non-drinkers who were intermediate or slow metabolizers. This association for fast metabolizers who drank 15-30 g/day was particularly pronounced among premenopausal women (premenopausal women OR=2.9, 95 % CI=1.2-7.1; postmenopausal women OR=1.8, 95% CI=0.9-3.8). These population-based data support the hypothesis that fast metabolizers of alcohol have a higher risk of breast cancer risk, from alcohol intake than slow metabolizers.

Alcohol and postmenopausal breast cancer risk defined by estrogen and progesterone receptor status: a prospective cohort study

BACKGROUND

Alcohol intake has been reported to be positively associated with an increased risk of postmenopausal breast cancer; however, the association with the estrogen receptor (ER) and progesterone receptor (PR) status of the breast tumors remains unclear.

METHODS

Self-reported data on alcohol consumption were collected in 1987 and 1997 from 51,847 postmenopausal women in the population-based Swedish Mammography Cohort. Through June 30, 2004, 1188 invasive breast cancer case patients with known ER and PR status were identified during an average 8.3-year follow-up. We used Cox proportional hazards models to estimate multivariable relative risks (RRs) of breast cancer, adjusting for age; family history of breast cancer; body mass index; height; parity; age at menarche, first birth, and menopause; education level; use of postmenopausal hormones; and diet. Heterogeneity among groups was evaluated using the Wald test. All statistical tests were two-sided.

RESULTS

Alcohol consumption was associated with an increased risk for the development of ER-positive (+) tumors, irrespective of PR status (highest intake [> or = 10 g of alcohol per day] versus nondrinkers, multivariable RR = 1.35, 95% confidence interval [CI] = 1.02 to 1.80; Ptrend < .049 for ER+PR+ tumors; and RR = 2.36, 95% CI = 1.56 to 3.56; Ptrend < .001 for ER+PR-tumors). The absolute rate of ER+ breast cancer (standardized to the age distribution of person-years experienced by all study participants using 5-year age categories) was 232 per 100,000 person-years among women in the highest category of alcohol intake, and 158 per 100,000 person-years among nondrinkers. No association was observed between alcohol intake and the risk of developing ER-tumors. Furthermore, we observed a statistically significant interaction between alcohol intake and the use of postmenopausal hormones on the risk for ER+PR+ tumors (Pinteraction = .039).

CONCLUSION

The observed association between risk of developing postmenopausal ER+ breast cancer and alcohol drinking, especially among those women who use postmenopausal hormones, may be important, because the majority of breast tumors among postmenopausal women overexpress ER.

Accumulating evidence on passive and active smoking and breast cancer risk

The aim of the study was to examine the risk of breast cancer associated with passive and active smoking and to explore risk heterogeneity among studies. Nineteen of 20 located published studies of passive smoking and breast cancer risk among women met basic quality criteria. Pooled relative risk estimates for breast cancer were calculated for 1) life-long non-smokers with regular passive exposure to tobacco smoke and 2) women who smoked. They were compared to women categorized as never regularly exposed to tobacco smoke. The pooled risk estimate for breast cancer associated with passive smoking among life-long non-smokers was 1.27 (95% confidence interval (CI), 1.11-1.45). In the subset of 5 studies (all case-control studies) with more complete exposure assessment (quantitative long-term information on the 3 major sources of passive smoke exposure: childhood, adult residential and occupational), the pooled risk estimate for exposed non-smokers was 1.90 (95%CI, 1.53-2.37). For the 14 studies with less complete passive exposure measures the risk was 1.08 (95%CI, 0.99-1.19) overall, 1.16 for 7 case-control and 1.06 for 7 cohort studies, although dose-response results in 3 of 4 Asian cohort studies suggested increased risk. The overall premenopausal breast cancer risk associated with passive smoking among life-long non-smokers was 1.68 (95%CI 1.33-2.12), and 2.19 (95% CI 1.68-2.84) for the 5 of 14 studies with more complete exposure assessment. For women who had smoked the breast cancer risk estimate was 1.46 (95%CI 1.15-1.85) when compared to women with neither active nor regular passive smoke exposure; 2.08 (95% CI 1.44-3.01) for more complete and 1.15 (95% CI 0.92-1.43) for less complete passive exposure assessment. Studies with thorough passive smoking exposure assessment implicate passive and active smoking as risk factors for premenopausal breast cancer. Cohort studies with thorough passive smoking assessment would be helpful and studies exploring biological mechanisms are needed to explain the unexpected similarity of the passive and active risks.

Hypothyroidism might be related to breast cancer in post-menopausal women

An association between breast cancer and thyroid (autoimmune) diseases or the presence of thyroid peroxidase antibodies (TPOAb; a marker of thyroid autoimmune disease) has been suggested. However, little is known about whether women with thyroid (autoimmune) diseases are at increased risk for developing breast cancer. This cross-sectional and prospective cohort study investigated whether the presence of TPOAb or thyroid dysfunction is related to the presence or development of breast cancer. An unselected cohort of 2,775 women around menopause was screened for the thyroid parameters thyrotropin (TSH), free thyroxine (FT(4)), and TPOAb during 1994. Detailed information on previous or actual thyroid disorders and breast cancer, and on putative factors related to breast cancer and thyroid disorders, was obtained. Clinical thyroid dysfunction was defined by both abnormal FT4 and TSH, and subclinical thyroid dysfunction by abnormal TSH (with normal FT4). A TPOAb concentration >or= 100 U/ml was defined as positive (TPOAb(+)). The study group was linked with the Eindhoven Cancer Registry to detect all women with (in situ) breast cancer (ICD-O code 174) diagnosed between 1958 and 1994. Subsequently, in the prospective study, all women who did not have breast cancer in 1994 (n = 2,738) were followed up to July, 2003, and all new cases of (in situ) breast cancer and all cancer-related deaths were registered. Of the 2,775 women, 278 (10.0%) were TPOAb(+). At the 1994 screening, 37 women (1.3%) had breast cancer. TPOAbs were (independently) related to a current diagnosis of breast cancer (OR = 3.3; 95% CI 1.3-8.5). Of the remaining women, 61 (2.2%) developed breast cancer. New breast cancer was related to: (1) an earlier diagnosis of hypothyroidism (OR = 3.8; 95% CI 1.3-10.9); (2) the use of thyroid medication (OR = 3.2; 95% CI 1.0-10.7); and (3) low FT4 (lowest tenth percentile: OR = 2.3; 95% CI 1.2-4.6). In the first 3 years follow up, the relationship between FT4 and log-TSH was disturbed in women with a new breast cancer diagnosis. The presence of TPOAb was not related to breast cancer during follow-up. A direct relationship between thyroid autoimmunity and breast cancer is unlikely. Hypothyroidism and low-normal FT4 are related with an increased risk of breast cancer in post-menopausal women. Studies are needed to clarify the origins of this possible association.

Dietary Patterns and the Risk of Breast Cancer

PURPOSE

Ecologic, migrant, and secular trend studies suggest an association between the Western diet and the risk of breast cancer. We examined data from the Nurses Health Study II to evaluate the association between major dietary patterns and the risk of breast cancer among pre-menopausal women.

METHODS

We derived "Western" and "prudent" dietary patterns from the responses of 90,638 premenopausal women, aged 26 to 46 years at baseline in 1991, who completed validated food frequency questionnaires in 1991 and 1995. These patterns were then evaluated for their associations with risk of breast cancer.

RESULTS

During 8 years of follow-up, we documented 710 cases of invasive breast cancer. The multivariate RR (95% CI) comparing highest to lowest quintiles of cumulative average score were 0.90 (0.68-1.18, p-value, test for trend = 0.54) for the prudent dietary pattern and 0.97 (0.71-1.33, p-value, test for trend = 0.97) for the Western dietary pattern.

CONCLUSIONS

Our findings suggest that there is no overall association between dietary patterns and risk of breast cancer. However, we found an inverse association between the prudent dietary pattern and breast cancer risk among ever smokers, but the test for interaction was not significant. We suggest that this finding merits further evaluation.

XRCC1 and XPD genetic polymorphisms, smoking and breast cancer risk in a Finnish case-control study

Introduction

It has been suggested that individuals with reduced DNA repair capacities might have increased susceptibility to environmentally induced cancer. In this study, we evaluated if polymorphisms in DNA repair genes XRCC1 (Arg280His, Arg399Gln) and XPD (Lys751Gln) modify individual breast cancer risk, with emphasis on tobacco smoking.

Methods

The study population consisted of 483 incident breast cancer cases and 482 population controls of Finnish Caucasian origin. The genotypes were determined by PCR-RFLP-based methods. Odds ratio (OR) and confidence intervals (CIs) were calculated by unconditional logistic regression analyses.

Results

No statistically significant overall effect in the breast cancer risk was seen for any of the studied polymorphisms. However, a significant increase in breast cancer risk was seen among ever smoking women if they carried at least one XRCC1-399 Gln allele (OR 2.33, 95% CI 1.30–4.19, p_int 0.025) or XPD-751 Gln/Gln genotype (OR 2.52, 95% CI 1.27–5.03, p_int 0.011) compared to smoking women not carrying these genotypes. The risks were found to be confined to women smoking at least five pack-years; the respective ORs were 4.14 (95% CI 1.66–10.3) and 4.41 (95% CI 1.62–12.0). Moreover, a significant trend of increasing risk with increasing number of the putative at-risk genotypes (p for trend 0.042) was seen. Women with at least two at-risk genotypes had an OR of 1.54 (95% CI 1.00–2.41) compared to women with no at-risk genotypes. Even higher estimates were seen for ever actively smoking women with at least two at-risk genotypes.

Conclusion

Our results do not indicate a major role for XRCC1 and XPD polymorphisms in breast cancer susceptibility, but suggest that they may modify the risk especially among smoking women.

Does dietary folate intake modify effect of alcohol consumption on breast cancer risk? Prospective cohort study

OBJECTIVE

To evaluate the effect of dietary folate intake on the relation between alcohol consumption and breast cancer risk.

DESIGN

Prospective cohort study.

SETTING

Melbourne, Australia.

PARTICIPANTS

17,447 Anglo-Australian women resident in Melbourne, aged 40-69 years at recruitment in 1990-4, and followed up until 31 December 2003.

MAIN OUTCOME MEASURE

Invasive breast cancers diagnosed during follow-up and ascertained through the Victorian cancer registry.

RESULTS

537 invasive breast cancers were diagnosed. Compared with lifetime abstainers, the hazard ratio for breast cancer in women who consumed an average of 40 g or more of alcohol daily at baseline was 1.41 (95% confidence interval 0.90 to 2.23). No direct association was found between dietary folate intake and risk of breast cancer, but a high folate intake mitigated the excess risk associated with alcohol. The estimated hazard ratio of an alcohol consumption of 40 g/day or more was 2.00 (1.14 to 3.49) for women with intakes of 200 mug/day of folate and 0.77 (0.33 to 1.80) for 400 mug/day of folate (P = 0.04 for interaction between alcohol and folate).

CONCLUSIONS

An adequate dietary intake of folate might protect against the increased risk of breast cancer associated with alcohol consumption.

Breast cancer: new technologies for risk assessment and diagnosis

In the US, one in every eight women will develop breast cancer in her lifetime. Despite the advances made in treating breast cancer, the causal mechanisms underlying this disease have yet to be fully elucidated; 85% of breast cancer cases occur sporadically without any known genetic mutation. Too little is known about the pathogenesis of breast cancer for primary prevention to be feasible in the near- to mid-term. Secondary prevention through screening offers an alternative that has been widely adopted. For decades, breast self-examination has been touted as a technique for the early identification of breast cancer. However, it has been recently suggested that this technique is a waste of time and resources for both doctors and patients. Mammography finds breast cancer earlier than breast self-examination, and will reduce the risk of death from breast cancer by approximately 30% in women over 50 years old. Mammography is limited in that cancer, like breast tissue, appears white on the x-ray; therefore lesions may be difficult to detect in women with very dense breasts, and a tumor may not cast a significant shadow until it is quite large. Some cancers are so aggressive that they can spread quickly, before routine screening can detect them. Despite these limitations, mammography is still viewed as the best tool currently available for screening and early diagnosis. Improved methods to detect and diagnose breast cancer early, when it is most curable, are required if a significant impact on morbidity and mortality from breast cancer is to be made. Various new and innovative technologies are being investigated for improving the early detection and diagnosis of breast cancer. About 85% of breast cancers begin in the milk ductal system of the breast. As cancer develops in the breast, abnormalities occur, including atypical hyperplasia, ductal carcinoma in situ, and invasive breast carcinoma. Thus, the early screening of ductal cells can provide a parallel benefit to the 'Pap' smear, which is used virtually universally to identify the abnormal cells that can lead to cervical cancer. Two technologies to monitor for atypical ductal epithelial cells are Cytyc Corporation's FirstCyte Ductal Lavage system and Nastech Pharmaceutical Company's Mammary Aspiration Cytology Test. Matritech, Inc. is searching for biomarkers linked to breast cancer. Researchers at Matritech have detected the presence of nuclear matrix protein (NMP) in the blood of women at the early stage of breast cancer, which is absent in the blood of healthy women, as well as those with fibroadenoma, a benign breast disease. NMP66 has been selected as a marker for further development and clinical trials of a test for use in the detection and monitoring of women with, or at risk for, breast cancer have been initiated. Technologies developed by the US Department of Defense are under investigation as breast cancer screening. Advanced Image Enhancement, Inc. has licensed naval sonar technology for digital image enhancement of mammograms. New thermography applications are also being investigated in two separate projects sponsored by the US Department of Defense using military thermal surveillance tools adapted for cancer detection. Both are enhancements of older thermal imaging technology based on the principle that heat equates to unwanted activity, in the case of breast cancer, abnormal cell proliferation.

Increased risk of esophageal cancer after breast cancer

BACKGROUND

Adjuvant radiation therapy for breast cancer has been related to excess esophageal cancer risk, but population-based data are scanty.

PATIENTS AND METHODS

We considered esophageal cancer risk among 11 130 breast cancer patients diagnosed between 1974 and 2002 in the Swiss cantons of Vaud and Neuchâtel, and followed-up to the end of 2002, for a total of 75 900 women-years at risk.

RESULTS

Overall, 18 cases were observed compared with 8.9 expected, corresponding to a standardised incidence ratio (SIR) of 2.0 [95% confidence interval (CI) 1.2-3.2]. The SIR was 1.6 in the first 10 years after diagnosis and 3.3 for >/=10 years after diagnosis, 2.3 for cases diagnosed between 1974 and 1988 and 1.5 for those diagnosed after 1988, 2.3 (based on 15 cases) for squamous cell cancer and 1.3 (based on three cases) for adenocarcinomas, and 2.9 for the upper third, 2.3 for the middle third and 1.9 for the lower third of the esophagus.

CONCLUSIONS

These data confirm an excess esophageal cancer risk following treatment for breast cancer which could not be explained by confounding of tobacco or alcohol alone. The excess risk tended to decrease for cases diagnosed after 1988, leaving open the issue of the risk of modern radiotherapy for breast cancer on esophageal cancer.

Cumulative genetic defects in carcinogen metabolism may increase breast cancer risk (The Netherlands)

Variants in the metabolic genes NAT1, NAT2, GSTM1 or GSTT1, may cause differences in individual detoxifying capacity of possible carcinogens. We examined the cumulative effect of putative at risk genotypes on breast cancer risk and we examined the extent to which these polymorphisms modify the association between smoking and breast cancer. A case cohort study was conducted in the DOM cohort with 676 breast cancer cases and a random sample of 669 individuals. No effect of the NAT1, NAT2 or GSTM1 genotypes on breast cancer risk was observed. However, women with GSTT1 null genotype had a 30% increased breast cancer risk compared to women with GSTT1 present (RR = 1.30 (95% confidence interval (CI) 1.04-1.64)). Smoking did not influence breast cancer risk nor did genetic variations in NAT1, NAT2 or GSTM1 in combination with smoking. Compared to women who never smoked with GSTT1 present, women with GSTT1 null genotype and who formerly smoked showed an increased breast cancer risk (RR = 2.55 (95% CI 1.10-5.90)), but current smokers who smoked 20 cigarettes or more per day did not (RR = 1.06 (95% CI 0.51-2.18)). Increasing numbers of putative at risk genotypes increased breast cancer risk in a dose dependent manner (p for trend 0.01). The risk was more than doubled in women with all four risk genotypes, RR = 2.45 (95% CI 1.24-4.86), compared to women with zero putative at risk genotypes. In conclusion, the results of this study suggest that presence of three or more putative at risk genotypes increases breast cancer risk.

Dietary patterns and breast cancer risk: results from three cohort studies in the DIETSCAN project

OBJECTIVE

Only a few consistent findings on individual foods or nutrients that influence breast cancer risk have emerged thus far. Since people do not consume individual foods but certain combinations of them, the analysis of dietary patterns may offer an additional aspect for assessing associations between diet and diseases such as breast cancer. It is also important to examine whether the relationships between dietary patterns and breast cancer risk are consistent across populations.

METHODS

We examined the risk of breast cancer with two dietary patterns, identified as "Vegetables" (VEG) and "Pork, Processed Meat, Potatoes" (PPP), common to all cohorts of the DIETSCAN project. During 7 to 13 years of follow-up, three of the cohorts--the Netherlands Cohort Study on diet and cancer (NLCS), the Swedish Mammography Cohort (SMC), and the Ormoni e Dieta nella Eziologia dei Tumori (Italy-ORDET)--provided data on 3271 breast cancer cases with complete information on their baseline diet measured by a validated food frequency questionnaire.

RESULTS

After adjustment for potential confounders, VEG was not associated with the risk of breast cancer across all cohorts. PPP was also not associated with the risk of breast cancer in SMC and ORDET, but a high PPP score tended to be inversely associated with breast cancer in the NLCS study (RR = 0.69; 95% CI, 0.52-0.92, highest versus lowest quartile). PPP differed in one aspect between the cohorts: butter loaded positively on the pattern in all cohorts except NLCS, in which butter loaded negatively and appeared to be substituted by low-fat margarine loading positively.

CONCLUSION

In general, the dietary patterns showed consistent results across the three cohorts except for the possible protective effect of PPP in the NLCS cohort, which could be explained by a difference in that pattern for NLCS. The results supported the suggestion derived from traditional epidemiology that relatively recent diet may not have an important role in the etiology of breast cancer.

Alcohol dehydrogenase 1B (ADH1B) genotype, alcohol consumption and breast cancer risk by age 50 years in a German case-control study

In a population-based study of 613 cases and 1082 controls, alcohol dehydrogenase 1B (ADH1B) genotype was not an independent risk factor for breast cancer, athough the possibility was raised that it modifies risk associated with high levels of alcohol consumption (OR 1.1, 95% confidence interval (CI) 0.8–1.6 for ADH1B*1/*1 genotype vs 0.2, 95% CI 0.1–1.0 for ADH1B*2 carriers).

MGMT genotype modulates the associations between cigarette smoking, dietary antioxidants and breast cancer risk

O(6)-methylguanine DNA methyl-transferase (MGMT) is the only known critical gene involved in cellular defense against alkylating agents in the DNA direct reversal repair (DRR) pathway. Three single nucleotide polymorphism (SNP) coding for non-conservative amino acid substitutions have been identified [C250T (Leu84Phe), A427G (Ile143Val) and A533G (Lys178Arg)]. To examine the importance of the DRR pathway in risk for breast cancer and the potential interaction with cigarette smoking and dietary antioxidants, we genotyped for these variants using biospecimens from the Long Island Breast Cancer Study Project. Genotyping was performed by a high throughput assay with fluorescence polarization and included 1067 cases and 1110 controls. Overall, there was no main effect between any variant genotype, haplotype or diplotype and breast cancer risk. Heavy smoking (>31 pack-year) significantly increased breast cancer risk for women with the codon 84 variant T-allele [odds ratio, OR = 3.0, 95% confidence interval (95% CI) = 1.4-6.2]. An inverse association between fruits and vegetables consumption and breast cancer risk was observed among women with the wild-type genotype for codon 84 (OR = 0.8, 95% CI = 0.6-0.9 for > or =35 servings of fruits and vegetables per week and CC genotype versus those with <35 servings per week and CC genotype). The association between fruits and vegetables consumption and reduced breast cancer risk was apparent among women with at least one variant allele for codon 143 (OR = 0.6, 95% CI = 0.5-0.9 for > or =35 servings of fruits and vegetables per week and AG or GG genotype versus those with <35 servings per week and AA genotype). Similar patterns were observed for dietary alpha-carotene and supplemental beta-carotene, but not for supplemental vitamins C and E. These data suggest that polymorphisms in MGMT may modulate the inverse association previously observed between fruits and vegetables consumption, dietary antioxidants and breast cancer risk, and support the importance of fruits and vegetables on breast cancer risk reduction.

Dietary patterns and the risk of postmenopausal breast cancer

The association between individual foods and breast cancer has been inconsistent. Therefore, we examined the association between diet and risk of postmenopausal breast cancer by the alternative approach of dietary patterns. Dietary patterns were identified with factor analysis from food consumption data collected from a food frequency questionnaire in 1984. Relative risks were computed using proportional hazard models and adjusted for known risk factors for breast cancer. Between 1984 and 2000, we ascertained 3,026 incident cases of postmenopausal breast cancer. We identified 2 major dietary patterns. The prudent pattern is characterized by higher intake of fruits, vegetables, whole grains, low-fat dairy products, fish and poultry, while the Western pattern is characterized by higher intake of red and processed meats, refined grains, sweets and desserts and high-fat dairy products. Neither of the patterns was associated with overall risk of postmenopausal breast cancer. However, a positive association between the Western pattern score was observed among smokers at baseline (relative risk = 1.44, comparing top to bottom quintiles; 95% CI = 1.02-2.03; p for trend = 0.03). An inverse association was observed between the prudent pattern and estrogen receptor-negative cancer (relative risk = 0.62; 95% CI = 0.45-0.88; p for trend = 0.006). Among the major food groups, higher consumptions of fruits (relative risk for 1 serving/day increase = 0.88; 95% CI = 0.80-0.97; p = 0.009) and vegetables (relative risk = 0.94; 95% CI = 0.88-0.99; p = 0.03) were significantly associated with decreased risk for ER(-) breast cancer. In conclusion, we did not observe an overall association between the prudent or Western pattern and overall breast cancer risk. However, a Western-type diet may elevate risk of breast cancer among smokers, and a prudent diet may protect against estrogen receptive-negative tumors.

Breast cancer

Breast cancer remains a public-health issue on a global scale. We report new information about the disease from the past 5 years. Early age at first birth, increasing parity, and tamoxifen use are related to long-term lifetime reduction in breast-cancer risk. Ductal carcinomas in situ has been suggested to be renamed ductal intraepithelial neoplasia to emphasise its non-life-threatening nature. An alternative approach, the progenitor/stem cell theory, predicts that only some tumour cells cause cancer progression and that these should be targeted by treatment. Mammography and ultrasonography are still the most effective for women with non-dense and dense breast tissues, respectively. Additionally, MRI, lymphatic mapping, the nipple-sparing mastectomy, partial breast irradiation, neoadjuvant systemic therapy, and adjuvant treatments are promising for subgroups of breast-cancer patients. Although tamoxifen can be offered for endocrine-responsive disease, aromatase inhibitors are increasingly used. Assessment of potential molecular targets is now important in primary diagnosis. Tyrosine-kinase inhibitors and other drugs with anti-angiogenesis properties are currently undergoing preclinical investigations.

Alcohol consumption and serum hormone levels during pregnancy

Factors that change sex hormone levels during pregnancy may have long-term health consequences for the offspring, including changes in breast cancer risk. A cross-sectional analysis of alcohol consumption and hormone levels in 339 pregnant women sampled from the Child Health and Development Study cohort was undertaken. Alcohol intake was queried from 1959 to 1966, long before any hazards of drinking during pregnancy were publicized. Third trimester serum hormone levels including estradiol and testosterone were analyzed. Among 339 pregnant women, 196 reported some alcohol consumption during pregnancy. The drinkers were divided into three groups with intake levels of 0.2-0.5, 0.6-2.0, and 2.1-12.5 ounces of ethanol per week. The second group corresponds to a median intake of approximately 2 drinks per week, and the last group corresponds to a median intake of approximately 1 drink per day, which is considered "light" to "moderate" drinking. Maternal estradiol levels were not associated with alcohol intake during pregnancy. However, serum testosterone was significantly lower, by 12.2%, in the latter two groups of drinking pregnant women, [confidence interval (CI)=-3.0 to 25.2] and 25.6% (CI=9.2-39.5), respectively. The alcohol intakes reported are far below those shown to cause fetal alcohol syndrome, or any of the fetal alcohol effects so far studied. Light alcohol intake during pregnancy is associated with lower maternal testosterone. The health implications are uncertain, but may include an increased breast density in the daughters of drinking mothers.

Inhibition of the rat breast cytosolic bioactivation of ethanol to acetaldehyde by some plant polyphenols and folic acid

There is a well-established association between alcohol consumption and breast cancer risk. About 4% of the breast cancers in developed countries are estimated to be attributable to drinking alcohol. The mechanism of tumor promotion by alcohol remains unknown. Recent studies from our laboratory and others showed the ability of mammary tissue to bioactivate ethanol to mutagenic/carcinogenic acetaldehyde and free radicals. Xanthine oxidoreductase (XOR) is an enzyme involved in those biotransformation processes. In the present study, we provide evidence of the ability of different natural polyphenols and of folic acid derivatives to inhibit the biotransformation of alcohol to acetaldehyde by rat breast cytosolic XOR. Folic acid and dihydrofolic acid, at concentrations of 10 microM, inhibited 100% and 84%, respectively, of the cytosolic acetaldehyde formation. Thirty-five polyphenols were tested in these initial experiments: ellagic acid, myricetin, quercetin, luteolin, and apigenin inhibited 79-95% at 10 microM concentrations. The remaining polyphenols were either less potent or noninhibitory of acetaldehyde formation at similar concentrations in these screening tests. Results are relevant to the known preventive effects of folic acid against alcohol-induced breast cancer and to their potential preventive actions if added to foods or alcoholic beverages.

The etiology of alcohol-induced breast cancer

Breast cancer is the most common cancer in women in the United States, and it is second among cancer deaths in women. Results of most epidemiologic studies, as well as of most experimental studies in animals, have shown that alcohol intake is associated with increased breast cancer risk. Alcohol consumption may cause breast cancer through different mechanisms, including through mutagenesis by acetaldehyde, through perturbation of estrogen metabolism and response, and by inducing oxidative damage and/or by affecting folate and one-carbon metabolism pathways. Alcohol-metabolizing enzymes are present in human breast tissue. Acetaldehyde is a known, although weak, mutagen. However, results of some studies with human subjects implicate this agent in the context of genetic susceptibilities to increased ethanol metabolism. Reactive oxygen species, resulting from ethanol metabolism, may be involved in breast carcinogenesis by causing damage, as well as by generating DNA and protein adducts. Alcohol interferes with estrogen pathways in multiple ways, influencing hormone levels and effects on the estrogen receptors. With regard to one-carbon metabolism, alcohol can negatively affect folate levels, and the folate perturbation affects DNA methylation and DNA synthesis, which is important in carcinogenesis. Some study results indicate that genetic variants of one-carbon metabolism genes might increase alcohol-related breast cancer risk. For all these pathways, genetic polymorphisms might play a role in increasing further a woman's risk for breast cancer. Additional studies are needed to determine the relative importance of these pathways, as well as the modifying influence by genetic variation.

Epidemiology of alcohol-associated cancers

Alcohol, especially in combination with smoking, is a well-established risk factor for cancers of the oral cavity and pharynx, esophagus, and larynx, with 25% to 80% of these cancers being attributable to alcohol. Rates of these cancers in the United States have been decreasing in recent years, possibly because of reductions in cigarette smoking and alcohol use. Chronic alcohol consumption has been linked with increased risk of liver cancer in epidemiologic studies. However, the rising rates of this cancer in the United States are most likely due to the increasing prevalence of chronic hepatitis B and C infections. Epidemiologic evidence has linked light to moderate intake of alcohol to cancers of the colorectum and female breast. These cancers are common in developed countries, so even small increases in risk can have important public health implications. Although results of most epidemiologic studies have provided little or no support for a causal relation between light and moderate alcohol use and risk of pancreatic cancer, a possible role of heavy alcohol consumption cannot be ruled out. Further studies of these cancers are needed to clarify the role of type of alcoholic beverage, the role of alcohol concentration, and the dose-response curve at low concentrations of alcohol. Future research also should be designed to promote the use of uniform ways to report alcohol intake and uniform measures for analysis, to include the investigation of alcohol-associated cancer risks in U.S. minority populations, to enhance experimental work to better understand the underlying mechanisms through which alcohol promotes carcinogenesis, and to develop preventive strategies.

Evaluation and outcome of behavioural changes in the rehabilitation of cancer patients: a review

The global increase in the number of newly diagnosed cancers has led in most affected countries to increased numbers of cancer survivors, who have specific needs for physical and psychosocial rehabilitation. In spite of recent progress, little is known about the specific rehabilitation measures that could increase the quality of life for cancer survivors. We reviewed published interventions that focussed on changing known risk factors for cancer recurrence and improving physical well-being; those we selected were exercise, smoking, alcohol consumption, diet and the use of sun screens. The published trials varied in the quality of the methods used, often had inadequate sample sizes and showed difficulty in validating outcomes. We conclude that there is still insufficient evidence to assess the importance of these behavioural risk factors in the rehabilitation of cancer patients. Future interventions should be designed to assess the separate effects of dietary changes, exercise and psychosocial interventions.

Nurse Counseling of Patients With an Overconsumption of Alcohol

PURPOSE

To identify the associations between self-reported alcohol-related clinical practice among hospital nurses and their (a) self-rated qualifications for counseling on alcohol, and (b) attitudes toward care of patients with an overconsumption of alcohol.

DESIGN AND METHODS

A survey based on self-administered questionnaires was undertaken at a Danish University Hospital in the Copenhagen area. Descriptive statistics, chi-square test, and multiple logistic regression analyses were used. Variables were self-reported alcohol-related counseling, self-rated qualifications for counseling patients with an overconsumption of alcohol, attitudes toward the priority of counseling on alcohol and other lifestyle issues, and attitudes toward caring for patients with an overconsumption of alcohol.

FINDINGS

Self-rated qualifications for counseling and attitudes toward care significantly influenced the self-reported clinical care of patients with an overconsumption of alcohol. Perceived self-efficacy was positively associated with frequent counseling and positive attitudes toward prevention. Psychiatric nurses were most active, medical nurses less active, and surgical nurses least active in counseling.

CONCLUSIONS

To promote nurse involvement in alcohol prevention, increasing the capacity for intervention via skill-based training on assessment of alcohol problems and intervention techniques is necessary. All nurses, but especially surgical nurses, needed updates on alcohol-related counseling.

Strategies for managing breast cancer risk after the menopause

Postmenopausal women in Western societies are conscious of breast cancer as a potential cause of death and ill health, which they wish to avoid with the advice of their doctors. Yet many factors that predispose women to the development of cancer will have been laid down before the menopause, in their genetic makeup or during their adolescent years. Even in middle age it is important to take account of the intrinsic level of risk, and to give women advice tailored to their own individual risk level. This results from their family history, previous diseases such as benign breast disease, and previous treatment for breast cancer or Hodgkin's disease. For those at the highest level of risk, strategies will include regular screening, prophylactic mastectomy, and the use of chemoprevention agents, such as tamoxifen. These women should avoid hormone replacement therapy (HRT) and control their menopausal symptoms and osteoporosis through the use of other agents now available - venlafaxine for menopausal symptoms and bisphosphonates for osteoporosis. Raloxifene is an agent under trial that may be valuable for breast cancer control as well as for osteoporosis. Women at standard population risk will require less robust preventive strategies, which will include screening and lifestyle modification. Their decisions regarding HRT should now be modified by recent evidence of associated risks. Recent studies show that tibolone causes less mammographic density and has a lower relative risk of breast cancer than combined estrogen/progestogen preparations. There is limited evidence that controlling obesity, participating in exercise and adopting a diet low in fats and high in fruit and vegetables will alter risk at this age. These precautions will, however, reduce the risk of other diseases common in this age group, such as hypertension, heart disease, stroke, and type 2 diabetes mellitus. Alcohol, even in small amounts, is a risk factor for breast cancer. Given the cardioprotective effect of moderate alcohol intake, advice on alcohol must reflect the individual relative risk of cardiovascular disease and breast cancer. Personal risk assessment is relevant for all women. Screening and a healthy lifestyle are worthwhile approaches for all, with the more aggressive approaches such as chemoprevention and prophylactic surgery reserved for those who have substantially elevated levels of risk. Once the menopause has passed, screening is probably the most effective evidence-based tool for breast cancer control by early diagnosis.

Facteurs de risque du cancer du sein

Because of its increasing incidence, breast cancer is a significant burden for women worldwide. In industrialized countries, breast cancer is the second-leading cause of cancer-related deaths among women, and it is estimated that 1 in every 8 women will develop the disease during her lifetime. Sufficient evidence indicates that a number of genetic, environmental and lifestyle risk exposures during life may play important roles in the etiology of this disease. The purpose of this paper is to review some etiologic factors and underlying mechanisms in relation to breast cancer risk. Based on the published literature, there is sufficient evidence that some established factors are associated with breast cancer risk. Age, early age at menarche, late menopause, height, post-menopausal obesity, family history of breast cancer, ionizing radiation, oral contraceptives, hormonal replacement therapy, mammographic density, some gene mutations and clinical conditions, such as benign breast disease, are associated with an increased risk of breast cancer. The risk decreases with early childbearing, high parity and physical activity, and breastfeeding. Alcohol increases the risk, while caloric restriction may confer protection from breast cancer. Epidemiological evidence for other nutritional factors is insufficient. These results suggest that breast cancer is a multifactorial disease where genetic susceptibility, environment, nutrition and other lifestyle risk factors interact. Better identification of modifiable risk factors and risk reduction of breast cancer may allow implementation of useful strategies for prevention.

Effects of alcohol on insulin-like growth factor I and insulin-like growth factor binding protein 3 in postmenopausal women

BACKGROUND

Increased circulating insulin-like growth factor I (IGF-I) concentrations, frequently adjusted for IGF binding protein 3 (IGFBP-3), have been associated with increased risk of several types of cancer, including colon, prostate, and breast. Studies have suggested that alcohol may affect IGF-I or IGFBP-3; however, controlled feeding studies to assess alcohol's effects on IGF-I or IGFBP-3 have not been conducted.

OBJECTIVE

To determine whether chronic, moderate alcohol intake affects serum IGF-I or IGFBP-3 concentrations, we performed a controlled, crossover feeding study.

DESIGN

Fifty-three postmenopausal women were randomly assigned to consume 0 g (control), 15 g (one drink), or 30 g (2 drinks) alcohol daily for 8 wk and were rotated through the other 2 intake levels in random order. All foods and beverages were provided during the intervention. Individuals were monitored and calories adjusted to maintain constant weight, and serum was collected at the end of each diet period.

RESULTS

Compared with the effects of 0 g alcohol/d, IGF-I concentrations were nearly unchanged by 15 g alcohol/d (0.8%; 95% CI: -3.2%, 3.5%) but decreased significantly by 4.9% (95% CI: -8.0%, -1.6%) with 30 g alcohol/d. IGFBP-3 concentrations significantly increased by 3.0% (95% CI: 0.4%, 5.6%) with 15 g alcohol/d but did not increase significantly with 30 g/d (1.8%; 95% CI: -0.9%, 4.5%).

CONCLUSIONS

To our knowledge, this is the first published controlled diet study to find that in postmenopausal women, when weight is kept constant, alcohol consumption reduces the amount of serum IGF-I potentially available for receptor binding. These findings suggest that the effect of alcohol intake should be considered in studies of IGF-I, IGFBP-3, and cancer in postmenopausal women.

Alcohol intake, type of beverage, and risk of breast cancer in pre- and postmenopausal women

BACKGROUND

Most studies of the relation between alcohol consumption and breast cancer have shown a modestly increased risk, although the results are still conflicting.

METHODS

The aim of this prospective population-based cohort study was to assess the influence of alcohol intake and type of beverage (beer, wine, or spirits) on breast cancer risk in relation to menopausal status. Among 13,074 women aged 20 to 91 years, we examined the relationship between breast cancer risk, total alcohol intake, and type of alcohol in relation to menopausal status. The women were classified as premenopausal or as postmenopausal at younger than 70 years or 70 years or more.

RESULTS

During follow-up, 76 premenopausal and 397 postmenopausal women developed breast cancer. Premenopausal women who had an intake of more than 27 drinks per week had a relative risk of breast cancer of 3.49 (95% confidence limits, 1.36-8.99) compared with light drinkers (p = 0.011), whereas there were no differences in risk in the lower-intake categories. The increased risk of breast cancer among premenopausal women was independent of the type of alcohol. Postmenopausal women older than 70 years of age who had an intake of more than six drinks per week of spirits had a relative risk of breast cancer of 2.43 (95% confidence limits, 1.41-4.20) compared with women who consumed less than one drink of spirits per week (p = 0.0014).

CONCLUSIONS

Total alcohol intake of more than 27 drinks per week increases breast cancer risk in premenopausal women independently of the type of alcohol. Among postmenopausal women, an intake of spirits of more than six drinks per week increases breast cancer risk.

Prospective study of alcohol consumption and breast cancer risk in Japanese women

Epidemiologic evidence is lacking for the association between alcohol consumption and the risk of breast cancer in Japanese women. We addressed this association in a prospective cohort study with an average follow-up of 7.6 years. At baseline (1988-1990), cohort participants completed a self-administered questionnaire that included alcohol use, reproductive history and hormone use. The women were followed up for breast cancer incidence through December 31, 1997. Cox proportional hazards models were used to calculate relative risks (RRs) and 95% confidence intervals (CIs) for breast cancer incidence and any association with alcohol consumption. During a follow-up of 271,412 person-years, we identified 151 women with breast cancer, of whom 45 were current drinkers and 11 drank > or =15 g of alcohol/day. After adjustment for age and other potential risk factors for breast cancer, the RR for current drinkers was 1.27 (95% CI 0.87-1.84) compared to nondrinkers. Average alcohol intake of <15 g/day did not significantly increase the risk for breast cancer. However, risk was significantly increased for women who consumed > or =15 g/day of alcohol (RR = 2.93, 95% CI 1.55-5.54). Age at starting drinking and frequency of consumption per week were not significantly associated with breast cancer risk. Our cohort study demonstrated that Japanese women who consume at least a moderate amount of alcohol have an increased risk of breast cancer.

Breast Cancer Risk Among Women Who Start Smoking as Teenagers

Objective: To examine the effect of smoking on breast cancer risk in a large population-based cohort of women, many of whom started smoking as teenagers.

Methods: We followed 102,098 women, ages 30 to 50 years, completing a mailed questionnaire at recruitment to the Norwegian-Swedish Cohort Study in 1991/1992, through December 2000. We used Cox proportional hazard regression models to estimate relative risk (RR) of breast cancer associated with different measures of smoking initiation, duration, and intensity adjusting for confounding variables. We conducted analyses on the entire study population, among women who had smoked for at least 20 years, among nondrinkers, and separately for each country.

Results: Altogether, 1,240 women were diagnosed with incident, invasive breast cancer. Compared with never smokers, women who smoked for at least 20 years and who smoked 10 cigarettes or more daily had a RR of 1.34 (95% CI, 1.06-1.70). Likewise, those who initiated smoking prior to their first birth (1.27, 1.00-1.62), before menarche (1.39, 1.03-1.87), or before age 15 (1.48, 1.03-2.13) had an increased risk. In contrast, women who had smoked for at least 20 years, but started after their first birth, did not experience an increased breast cancer risk. The increased RR associated with smoking was observed among nondrinkers of alcohol, women with and without a family history of breast cancer, premenopausal and postmenopausal women, and in both countries.

Conclusion: Our results support the notion that women who start smoking as teenagers and continue to smoke for at least 20 years may increase their breast cancer risk.

Problems with using biomarkers as surrogate end points for cancer: a cautionary tale

Investigations employing surrogate cancer end points are especially attractive because they may be smaller, shorter, and cheaper than comparable studies with explicit cancer outcomes. For many potential surrogate end points--epithelial cell proliferation will be taken as an example--inferences are problematic because of the existence of alternative causal pathways to cancer that bypass the surrogate end point. Evaluating potential surrogates requires information on the following three questions: (1) What is the relation of the surrogate end point to cancer? (2) What is the relation of the intervention (or exposure) to the surrogate? (3) To what extent does the surrogate end point mediate the relation between intervention (exposure) and cancer? Data for these questions may derive from animal experiments, human metabolic studies, observational epidemiologic investigations (including ecologic studies), and randomized trials. Inferences to cancer from such downstream markers as colorectal adenomatous polyps and persistent human papillomavirus infection of the cervix are strong, though not absolutely unassailable. For all but these very-close-to-cancer markers, considerable caution is warranted in extrapolating from surrogate effects or associations to cancer.

Behaviour partly explains educational differences in cancer incidence in the south-eastern Netherlands: the longitudinal GLOBE study

Cancer morbidity and mortality vary among socio-economic groups. We investigated whether educational differences in behaviour could explain the variation in cancer incidence. In 1991, a postal questionnaire on socio-economic status, exposure variables, health and health-related behaviour was filled out by 18,973 participants (response rate 70.1%) of the longitudinal GLOBE study. Participants were followed and linked with the regional population-based Eindhoven Cancer Registry. Between 1991 and 1998 a total of 760 new tumours were found. The risk of cancer (all sites combined) was higher in the three quartiles of lower educational level compared with the highest educational level, odds ratios (ORs) varying from 1.25, 1.34, 1.27 to 1.00 from the lowest to the highest category, respectively (P=0.14). The relative risk (RR) for lung cancer for low versus high education was 2.7 [95% confidence interval (CI) 1.3-5.3]; adjustment for smoking, alcohol intake and physical activity decreased the risk to 1.6 (95% CI 0.8-3.3). Smoking alone explained 39% of the association, when alcohol intake and physical exercise were added to the model 61% of the effect was explained. In conclusion, a lower education is associated with increased cancer risks, which can be explained partly by behavioural factors.

Common risk factors of breast and ovarian cancer: recent view

Clinicians, epidemiologists, and public health specialists tend to examine breast and ovarian cancer separately. Although this seems fairly rational and expected, both malignancies are estrogen related and thus share many risk factors. In this review, we investigate the common familial, reproductive, anthropometric, nutritional, and lifestyle risk factors of breast and ovarian cancer. We believe that the parallel examination of the two cancer types could significantly contribute to an improved prevention of "gynecological cancer" as a whole.

Effects of Alcohol and Menstrual Cycle on Insulin-like Growth Factor-I and Insulin-like Growth Factor Binding Protein-3

Alcohol ingestion and insulin-like growth factor-I (IGF-I) have been associated with increased breast cancer risk, the latter primarily in premenopausal women. We investigated whether alcohol ingestion altered IGF-I or its major binding protein (BP), IGFBP-3, in a controlled feeding study in premenopausal women. We also determined whether IGF-I or IGFBP-3 was affected by menstrual cycle phase. Serum was collected from 31 individuals who were randomly assigned to consume either 0 or 30 g (two drinks) of alcohol daily for three menstrual cycles and who then crossed over to the other alcohol level for three cycles. All calories were provided and weight was maintained during the study. For both alcohol levels, serum was collected during the final cycle at early follicular, periovulatory, and luteal phases. Relative to the follicular phase, IGF-I levels increased by 3.3% and 7.6% in the periovulatory and luteal phases, respectively (P for trend = 0.004). Although alcohol ingestion did not affect this increase, it significantly reduced IGF-I concentrations at all phases (9.5%; P &lt; 0.001), whereas IGFBP-3 was unaffected by either menstrual phase or alcohol. This is the first controlled diet study to show that alcohol decreases serum IGF-I in premenopausal women and that IGF-I significantly increases over the course of the menstrual cycle whether or not alcohol is present.

Alcohol Exposure and Breast Cancer: Results of the Women's Contraceptive and Reproductive Experiences Study

Objectives: To explore associated biological outcomes and clarify the role of timing of exposure in the alcohol-breast cancer relationship.

Methods: In a population-based study of 4,575 women ages 35 to 64 years diagnosed with invasive breast cancer between 1994 and 1998 and 4,682 controls, we collected details of lifetime alcohol use and factors that could confound or modify the alcohol-breast cancer relationship. We used conditional logistic regression to compute the odds of breast cancer among drinkers relative to nondrinkers at all ages and at ages 35 to 49 and 50 to 64 years separately.

Results: Recent consumption (at reference age minus two) of ≥7 drinks per week was associated with increased risk [odds ratio (OR), 1.2; 95% CI, 1.01-1.3] and evidence of dose response was observed. Most of the excess was observed among women ages 50-64 years (OR 1.3; 95% CI, 1.1-1.6), although the test for age interaction was not statistically significant. Exposure later in life seemed more important than early exposure. Excess breast cancer associated with recent consumption was restricted to localized disease. When outcome was examined according to tumor hormone receptor status, highest risks were observed for estrogen receptor–positive/progesterone receptor–negative tumors (OR 1.6; 95% CI, 1.2-2.3).

Conclusions: The effect of timing of alcohol exposure on breast cancer risk is complicated and will require additional study focused on this one issue. Further work is needed to explain how alcohol exposure, sex hormones, and tumor receptor status interact.

Women and tobacco dependence

Millions of American girls and women have been drawn to smoking by an industry that has been clearly and systematically targeting women of all ages and life circumstances. Tobacco marketing strategies skillfully link cigarette use to typical female values. Biologically speaking, women are especially vulnerable to the legion of health problems of tobacco use. Smoking is a critical hazard for women in their reproductive years, particularly when they are pregnant.

Presence of papillomavirus sequences in condylomatous lesions of the mamillae and in invasive carcinoma of the breast

BACKGROUND

Viruses including Epstein-Barr virus (EBV), a human equivalent of murine mammary tumour virus (MMTV) and human papillomavirus (HPV) have been implicated in the aetiology of human breast cancer. We report the presence of HPV DNA sequences in areolar tissue and tumour tissue samples from female patients with breast carcinoma. The presence of virus in the areolar-nipple complex suggests to us a potential pathogenic mechanism.

METHODS

Polymerase chain reaction (PCR) was undertaken to amplify HPV types in areolar and tumour tissue from breast cancer cases. In situ hybridisation supported the PCR findings and localised the virus in nipple, areolar and tumour tissue.

RESULTS

Papillomavirus DNA was present in 25 of 29 samples of breast carcinoma and in 20 of 29 samples from the corresponding mamilla. The most prevalent type in both carcinomas and nipples was HPV 11, followed by HPV 6. Other types detected were HPV 16, 23, 27 and 57 (nipples and carcinomas), HPV 20, 21, 32, 37, 38, 66 and GA3-1 (nipples only) and HPV 3, 15, 24, 87 and DL473 (carcinomas only). Multiple types were demonstrated in seven carcinomas and ten nipple samples.

CONCLUSIONS

The data demonstrate the occurrence of HPV in nipple and areolar tissues in patients with breast carcinoma. The authors postulate a retrograde ductular pattern of viral spread that may have pathogenic significance.

Environmental tobacco smoke and breast cancer incidence

To evaluate whether environmental tobacco smoke (ETS) influences breast cancer incidence, data from a population-based case-control study were analyzed. Respondents with available ETS information assessed by in-person questionnaires included 1356 newly diagnosed cases and 1383 controls. Relative to nonsmokers who reported no residential ETS exposure throughout the life course, the odds ratios (OR) for breast cancer were not substantially elevated in relation to ETS exposure, active smoking, or a joint measure of active and passive smoking (OR, 1.15, 95% CI, 0.90, 1.48). An increased OR, however, was noted among nonsmokers who lived with a smoking spouse for over 27 years (2.10, 95% CI, 1.47, 3.02), although no dose-response was evident. Also, among women with hormone-receptor-positive tumors only, the OR for both active and passive smoking was increased (1.42 for ER+ PR+, 95% CI, 1.00, 2.00). Our data suggest that if there is an effect for ETS on breast cancer, that effect is restricted to selected subgroups of women, such as those with long-term exposure from a smoking spouse.

Glutathione S-transferases M1, T1, and P1 and Breast Cancer: A Pooled Analysis

The glutathione S-transferase (GST) genes are involved in the metabolism of various carcinogens. Deletion polymorphisms in the genes GSTM1 and GSTT1 and a base transition polymorphism at codon 105 (Ile→Val) in GSTP1 were investigated in relation to breast cancer risk. Tobacco smoking and reproductive factors were examined as potential effect modifiers. Individual data from seven case-control studies were pooled within the International Collaborative Study on Genetic Susceptibility to Environmental Carcinogens. To measure the effect of GSTs on breast cancer risk, odds ratios and 95% confidence intervals were computed adjusting for study center and age. The modifying effect was investigated by stratification on variables of smoking habits and reproductive history. A total of 2,048 cases with breast cancer and 1,969 controls were analyzed. The relative odds ratio (95% confidence interval) of breast cancer was 0.98 (0.86–1.12) with the GSTM1 null, 1.11 (0.87–1.41) with the GSTT1 null, 1.01 (0.79–1.28) with GSTP1 heterozygous mutants, and 0.93 (0.62–1.38) with GSTP1 homozygous mutants. Stratification by smoking or reproductive factors did not reveal a modifying effect of these variables, nor was there any association between GSTM1 and age at diagnosis of breast cancer. This is the largest study investigating susceptibility to breast cancer due to polymorphisms in the GST genes. The results conclusively show that single gene GST polymorphisms do not confer a substantial risk of breast cancer to its carriers. Furthermore, GSTs did not interact with smoking or reproductive history to modify cancer risk.

Fertility pattern does not explain social gradient in breast cancer in denmark

The present study was undertaken to assess the impact of reproductive behavior on the social class gradient in breast cancer occurrence in Denmark. Objectives were to study whether the gradient across socioeconomic groups could be explained by fertility differences, whether the gradient across educational groups could be explained by fertility differences and whether the effect of socioeconomic group on breast cancer incidence and mortality could be explained by education and vice versa. We studied 674,084 women aged 20-39 at the census on 9 November 1970 for whom we had complete data on fertility history. The cohort was followed up for breast cancer incidence and mortality until 8 November 1998. Fertility history varied considerably across socioeconomic group, where 38% of the academics were childless at the age of 30, in contrast to only 8% of women in agriculture. The academics had the highest risk of breast cancer and women in agriculture had the lowest risk. For incidence, the gradient in the relative risks was 1.74, which changed to 1.49 when fertility history was incorporated and to 1.29 when school education was also taken into account. For school education, women with > or = 12 years of schooling had the highest risk and women with < or = 7 years of schooling had the lowest risk. For incidence, the gradient in the relative risk was 1.38, which changed to 1.26 when fertility history was incorporated and to 1.22 when socioeconomic group was also taken into account.

The changing global patterns of female breast cancer incidence and mortality

One in ten of all new cancers diagnosed worldwide each year is a cancer of the female breast, and it is the most common cancer in women in both developing and developed areas. It is also the principal cause of death from cancer among women globally. We review the descriptive epidemiology of the disease, focusing on some of the key elements of the geographical and temporal variations in incidence and mortality in each world region. The observations are discussed in the context of the numerous aetiological factors, as well as the impact of screening and advances in treatment and disease management in high-resource settings.

Alcohol consumption: an overview of benefits and risks

Published health benefits of regular light-to-moderate alcohol consumption include lower myocardial infarction rates, reduced heart failure rates, reduced risk of ischemic stroke, lower risk for dementia, decreased risk of diabetes and reduced risk of osteoporosis. Numerous complimentary biochemical changes have been identified that explain the beneficial effects of moderate alcohol consumption. Heavy alcohol consumption, however, can negatively affect neurologic, cardiac, gastrointestinal, hematologic, immune, psychiatric and musculoskeletal organ systems. Binge drinking is a significant problem even among moderate drinkers and is associated with particularly high social and economic costs. A cautious approach should be emphasized for those individuals who drink even small amounts of alcohol. Physicians can apply the research evidence describing the known risks and benefits of alcohol consumption when counseling their patients regarding alcohol consumption.

Towards an integrated model for breast cancer etiology: the lifelong interplay of genes, lifestyle, and hormones

While the association of a number of risk factors, such as family history and reproductive patterns, with breast cancer has been well established for many years, work in the past 10–15 years also has added substantially to our understanding of disease etiology. Contributions of particular note include the delineation of the role of endogenous and exogenous estrogens to breast cancer risk, and the discovery and quantification of risk associated with several gene mutations (e.g. BRCA1). Although it is difficult to integrate all epidemiologic data into a single biologic model, it is clear that several important components or pathways exist. Early life events probably determine both the number of susceptible breast cells at risk and whether mutations occur in these cells. High endogenous estrogens are well established as an important cause of breast cancer, and many known risk factors appear to operate through this pathway. Estrogens (and probably other growth factors) appear to accelerate the development of breast cancer at many points along the progression from early mutation to tumor metastasis, and appear to be influential at many points in a woman's life. These data now provide a basis for a number of strategies that can reduce risk of breast cancer, although some strategies represent complex decision-making. Together, the modification of nutritional and lifestyle risk factors and the judicious use of chemopreventive agents could have a major impact on breast cancer incidence. Further research is needed in many areas, but a few specific arenas are given particular mention.

Cigarette smoke condensate-induced transformation of normal human breast epithelial cells in vitro

In the present study, we showed that a single-dose treatment of normal breast epithelial cell line, MCF10A, for 72 h with cigarette smoke condensate (CSC) resulted in a transformed phenotype. The anchorage-dependent growth of these cells was decreased due to increased cell cycle arrest in S-G2/M phase; however, the surviving cells developed resistance due to an increased Bcl-xL to Bax ratio. Levels of PCNA and gadd45 proteins--involved in DNA repair in response to genomic damage--were increased, suggesting that the cells were responding to CSC-induced genomic damage. The transformation of MCF10A cells was determined by their colony-forming efficiency in soft-agar in an anchorage-independent manner. CSC-treated MCF10A cells efficiently formed colonies in soft-agar. We then re-established cell lines from the soft-agar colonies and further examined the persistence of their transforming characteristics. The re-established cell lines, when plated after 17 passages without CSC treatment, still formed colonies in the soft-agar. An increased staining of neuropilin-1 (NRP-1) further showed a transformation characteristic of MCF10A cells treated with CSC. In summary, our results suggest that CSC is capable of transforming the MCF10A cells in vitro, supporting the role of cigarette smoking and increased risk for breast cancer.

Use of Oral Contraceptives, Alcohol, and Risk for Invasive Breast Cancer

The aim of our study was to examine how the use of oral contraceptives (OCs) interact with alcohol on breast cancer risk within the large prospective follow-up study, Norwegian Women and Cancer Study. Between 1991 and 1997, women aged 30 to 70 years were drawn at random from the central person register and mailed an invitation. Follow-up information was collected throughout 2001 by linkage to national registries. Only women (n = 86,948) with complete information on alcohol consumption and duration of OC use were included in the present analysis. A total of 1,130 invasive breast cancers were diagnosed during 618,638 person-years of follow-up. Consumption of ≥10.0 g/d alcohol was associated with a breast cancer relative risk (95% confidence interval) of 1.69 (1.32-2.15), consistent with a linear relationship (P for trend &lt; 0.0001). Among alcohol consumers, an excess risk of breast cancer was observed for total duration of OC use only among women who consumed &lt;5 g/d alcohol (P for trend = 0.0009). We observed a negative interaction between duration of OC use and alcohol consumption effects (P for interaction = 0.01). After stratification on menopausal status, the association between high alcohol intake and breast cancer was more prominent among postmenopausal women than among premenopausal women (P for heterogeneity = 0.01). No interaction between alcohol and duration of OC use were significant after stratification on menopausal status. Our findings in conjunction with biological data imply that alcohol and OCs have antagonistic effects on breast cancer risk through a common pathway. Whether the interactive effect differs according to menopausal status remains unclear and needs further investigations.

Health behavior change among women with recent familial diagnosis of breast cancer

BACKGROUND

Although first-degree female relatives (FDFR) of women with breast cancer are at increased risk for the disease, little is understood about how familial diagnosis impacts health behaviors and what personal factors predict such changes.

METHODS

Six hundred women, ages 18 and over with a FDFR recently diagnosed with breast cancer, were interviewed after the diagnosis and again in 6 months. Participants self-reported changes in physical activity, fruit and vegetable consumption, fat consumption, alcohol and tobacco use. The effect of baseline demographics, health status, perceptions of relative's disease severity, personal risk, control over the disease and the effect of lifestyle behaviors on risk was assessed in relation to behavior changes.

RESULTS

Forty-two percent reported improving one or more behaviors. Perception that the behavior was a risk factor for breast cancer was positively associated with change for all behaviors except smoking. Poor health status, obesity and perception of control over breast cancer were associated with improvements in physical activity, fruit and vegetable consumption and fat consumption.

CONCLUSIONS

Diagnosis of breast cancer in a first-degree relative can provide motivation to improve health behavior. Educational interventions highlighting the importance of these behaviors in reducing breast cancer risk and promoting health in general may be effective in this population.

In utero alcohol exposure increases mammary tumorigenesis in rats

Findings in humans and animal models suggest that in utero hormonal and dietary exposures increase later breast cancer risk. Since alcohol intake by adult women consistently increases their breast cancer risk, we wondered whether maternal alcohol consumption during pregnancy increases female offspring's mammary tumorigenesis. In our study, pregnant female rats were pair-fed isocaloric diets containing either 0 (control), 16 or 25 g alcohol kg(-1) feed between days 7 and 19 of gestation. These alcohol exposures generate blood alcohol levels that correspond to low and moderate alcohol consumption and are lower than those that induce foetal alcohol syndrome. Serum oestradiol levels were elevated in pregnant rats exposed to alcohol (P<0.003). When adult, female offspring of alcohol-exposed dams developed significantly more 7,12-dimethylbenz[a]anthracene -induced mammary tumours, compared to the controls (tumour multiplicity; mean+/-s.e.m., controls: 2.0+/-0.3, 16 g alcohol: 2.7+/-0.4 and 25 g alcohol: 3.7+/-0.4; P<0.006). In addition, the mammary epithelial tree of the alcohol-exposed offspring was denser (P<0.004) and contained more structures that are susceptible for the initiation of breast cancer (P<0.001). Immunohistochemical assessment indicated that the mammary glands of 22-week-old in utero alcohol-exposed rats contained elevated levels of oestrogen receptor-alpha (P<0.04) that is consistent with the changes in mammary gland morphology. In summary, maternal alcohol intake during pregnancy increases female offspring's mammary tumorigenesis, perhaps by programming the foetal mammary gland to exhibit persistent alterations in morphology and gene expression. It remains to be determined whether an increase in pregnancy oestradiol levels mediated alcohol's effects on offspring's mammary tumorigenesis.

Intake of specific carotenoids and essential fatty acids and breast cancer risk in Montreal, Canada

BACKGROUND

Evidence from previous investigations into the possible role of dietary and serum carotenoid concentrations in the etiology of breast cancer is inconsistent. No study has examined the combined effect of carotenoids and essential fatty acids on the risk of breast cancer.

OBJECTIVE

The objective was to assess the possible association between specific and total carotenoids and breast cancer risk and to evaluate the effect modification by diet-related fatty acids and lifestyle factors in the development of breast cancer.

DESIGN

A population-based case-control study involving 414 incident cases and 429 controls was conducted in French Canadians in Montreal. Dietary intake was estimated with the use of a validated food-frequency questionnaire in face-to-face interviews.

RESULTS

No significant association was apparent between any of the individual or total carotenoids and the risk of breast cancer after adjustment for major underlying determinants of breast cancer. In premenopausal women who ever smoked, an increased risk was related to alpha-carotene [odds ratio (OR) for the upper relative to the lowest quartiles of intake: 2.40; 95% CI: 0.90, 6.41; P for trend = 0.046]. Conversely, a reduced risk was related to beta-carotene (OR: 0.57; 95% CI: 0.26, 1.24; P for trend = 0.05) in women who never used hormone replacement therapy. In postmenopausal women, total carotenoids were positively associated with breast cancer risk in those with a high arachidonic acid intake (OR: 1.92; 95% CI: 0.93, 3.94; P = 0.028 for trend) and inversely associated in those with a high docosahexaenoic acid intake (OR: 0.52; 95% CI: 0.25, 1.07; P for trend = 0.054).

CONCLUSION

These findings suggest that the combined high intake of total carotenoids and docosahexaenoic acid may reduce the risk of breast cancer.

Epidemiology of breast cancer among BRCA mutation carriers: an overview

Mutations in BRCA1 and BRCA2 have been associated with an increased lifetime risk of breast and ovarian cancers. Many of the well-recognized risk factors and risk modifiers in other women appear to operate similarly in BRCA mutation carriers. However, current evidence suggests that BRCA-related breast cancer risk is positively associated with pregnancy and parity, while smoking may reduce the risk. The incidence of BRCA1-related breast cancer is high before the age of 35 years and oral contraceptive use for 5 or more years is associated with increased risk of this disease among women carrying BRCA1 mutations.