Inflammatory breast cancer and body mass index

PURPOSE: No studies have investigated the etiology of inflammatory breast cancer (IBC), the most lethal form of breast cancer. Because high body mass index (BMI) is associated with decreased risk of premenopausal breast cancer but increased risk of postmenopausal breast cancer, we evaluated whether high BMI was a risk factor for IBC. PATIENTS AND METHODS: In a case-comparison study, we matched by ethnicity and registration date 68 IBC patients treated at The University of Texas M.D. Anderson Cancer Center from 1985 to 1996 with 143 patients with non-IBC and 134 patients with cancer at sites other than the breast or reproductive tract (non-breast cancer). The non-breast cancer group was used in lieu of a population-based, healthy control group, which was not available. RESULTS: IBC patients were younger at menarche and the time of their first live birth than non-IBC and non-breast cancer patients. The proportion of premenopausal IBC patients was higher than the proportion of premenopausal women in the comparison groups, although differences were not significant. There were no differences in height, but IBC patients were heavier (77.6 kg) than non-IBC (70.0 kg) and non-breast cancer patients (68.0 kg). After adjusting for other factors, women in the highest BMI tertile (BMI > 26.65 kg/m2) relative to the lowest tertile (BMI < 22.27) had significantly increased IBC risk (IBC v non-IBC, odds ratio [OR] = 2.45, 95% confidence interval [CI] = 1.05 to 5.73; IBC v non-breast cancer, OR = 4.52, 95% CI = 1.85 to 11.04). This association was not significantly modified by menopausal status and was independent of age at menarche, family history of breast cancer, gravidity, smoking status, and alcohol use. CONCLUSION: Our investigation showed that high BMI was significantly associated with an increased risk of IBC. This association did not vary by menopausal status, although IBC patients were more likely to be premenopausal. Confirming our findings and identifying other IBC risk factors may provide directions for future research on the aggressive nature of IBC.     

Reproductive factors and risk of brain, colon, and other malignancies in Iowa (United States)

The influence of parity on the risk of cancers of the female breast and reproductive organs is well established. However, non-reproductive sites have received less attention. Mail questionnaire data gathered from incident female cases (169 brain; 332 colon; 260 rectal; 145 kidney; and 169 pancreas cancers), and 821 population-based controls in Iowa (United States) were used to measure the effect of parity and age at first birth on risk of these malignancies. Relative to nulliparous women, ever-parous women were at significantly decreased risk of brain cancer (odds ratio [OR] = 0.44, 95 percent confidence interval [CI] = 0.3-0.7) and of colon cancer (OR = 0.67, CI = 0.5-0.97), after adjustment for age and other risk factors. The OR for the other sites did not differ significantly from 1.0. The lower risk of brain cancer among parous women was similar in younger and older age groups, in patients diagnosed with glioblastoma and astrocytoma, and among ever- and never-smokers. The findings for colon cancer are consistent with observations from other studies. In the context of limited laboratory and clinical evidence implicating hormones in brain neoplasia, these findings may suggest a role for hormonal factors in brain cancer etiology. Hormonal factors deserve more detailed future consideration as risk factors in brain cancer.     

Alcohol and breast cancer in the Swiss Canton of Vaud

The relationship between alcoholic beverage drinking and the risk of breast cancer was considered using data from a case-control study of breast cancer conducted between 1990 and 1995 in the Swiss Canton of Vaud on 230 incident cases of breast cancer below age 75 years, linked with the Vaud Cancer Registry, and 507 controls admitted to the same network of hospitals for a wide spectrum of acute, non-neoplastic, non-hormone-related conditions. Overall, 70.4% of cases versus 57.4% of controls consumed alcohol, corresponding to a multivariate odds ratio (OR) of 1.5 (95% confidence interval (CI): 1.1-2.2). The ORs were 1.3 for < 1 drink per day, 1.8 for 1 to 2, 1.5 for 2 to 4, and 2.7 for > 4 drinks per day, and the trend in risk with dose was significant. The association was consistent for wine (OR = 2.0), beer (OR = 2.6) and spirits (OR = 2.0) and was apparently stronger in premenopausal women, whereas no noticeable interaction was observed with any of the hormonal or reproductive risk factors for breast cancer. The alcohol-related risk was unrelated to duration; the OR was 1.8 for women who started drinking below the age of 30 years and 1.4 for those starting at the age of > or = 30 years. Thus, the present study confirms that alcohol is a correlate of breast cancer risk in this European population, where alcohol drinking among women is common and relatively high. Assuming that this association reflects causality, in terms of attributable risk, alcohol could explain 25% (8-42%) of breast cancer cases.     

Symptom-related self-care of Mexican Americans with type 2 diabetes: preliminary findings of the Starr County Diabetes Education Study

OBJECTIVES: Late age at first birth and nulliparity are established risk factors for breast cancer, yet the extent to which fertility problems contribute to these associations remains largely unexplored. Here, we examine self-reported fertility problems as a risk factor for breast cancer in young women. METHODS: We used a population-based case-control study of 2,173 cases and 1,990 controls aged 20 to 54 years in the United States. Structured in-person interviews were used to elicit detailed information on established and potential breast cancer risk factors. Information was collected on pregnancy details, including difficulties becoming pregnant or maintaining a pregnancy. RESULTS: Self-reported difficulty in becoming pregnant or maintaining a pregnancy was reported by 450 cases and 377 controls. Overall, there was little association between these fertility problems and risk of breast cancer (odds ratio [OR] = 1.05). Parity was associated with a decreased risk of breast cancer in women both with (OR = 0.71) and without (OR = 0.79) fertility problems. There was little evidence of an increased risk of breast cancer with later age at first full-term birth among women without fertility problems (ORage 35+ :age <20 = 1.13, 95 percent confidence interval [CI] = 0.7-1.9), but a relatively strong association among women with fertility problems (ORage 35+ :age <20 = 2.96, CI = 1.3-7.0). Among women with a first full-term birth at age 35 or older, fertility problems were associated with a twofold risk of breast cancer. Analyses of duration of unprotected sexual intercourse prior to first pregnancy as an alternative estimate of infertility produced similar results. CONCLUSIONS: Our study suggests that the association between late age at first birth and breast cancer is stronger among women with self-reported fertility problems than among women with no fertility problems.     

History of lactation and breast cancer risk

A self-administered questionnaire was completed by 1,018 women diagnosed with breast cancer during 1988-1989 identified through the British Columbia Cancer Registry and by 1,025 controls selected at random from the Provincial Voters List. Parous premenopausal women who had never nursed (odds ratio (OR) = 1.3, 95% confidence interval (CI) 0.9-2.0) or who had lactated for 1 month or less (OR = 1.8, 95% CI 1.3-2.5) had an increased risk of breast cancer adjusted for age and parity, compared with women who had breast-fed 2 months or longer. The risk was particularly elevated (OR = 3.0, 95% CI 1.6-5.4) among women who reported having tried to nurse, but who were unsuccessful. Among women who nursed for at least 2 months, there was an indication of decreasing risk with increasing duration of nursing. Among postmenopausal parous women, no relation between lactation history and breast cancer risk was evident.     

Degradation and repair of elastic fibers in rat lung interstitial fibroblast cultures

The results from previous studies have provided evidence to support the hypothesised association between intrauterine oestrogen exposure and subsequent risk of breast cancer. Information has not been available to study this relationship for several perinatal factors thought to be related to pregnancy oestrogen levels. Data collected from the mothers of women in two population-based case-control studies of breast cancer in women under the age of 45 years (510 case mothers, 436 control mothers) who were diagnosed between 1983 and 1992 in three western Washington counties were used to investigate further the relationship between intrauterine oestrogen exposure and risk of breast cancer. A pregnancy weight gain of 25-34 pounds was associated with breast cancer risk (odds ratio [OR] = 1.5; 95% confidence interval [CI] 1.1, 2.0); however, women whose mothers gained 35 pounds or more were not at increased risk. Use of antiemetic medication in women with any nausea and vomiting (OR = 2.9; 95% CI 1.1, 8.1) and use of diethylstilboestrol (DES) (OR = 2.3; 95% CI 0.8, 6.4) appeared to be positively associated with breast cancer risk. The results from this study provide limited support for the hypothesis that in utero oestrogen exposure may be related to subsequent breast cancer risk among young women.     

Biologic activity of interleukin 1 (IL-1) alpha in patients with refractory malignancies

To examine the effects of smoking and N-acetylation genetics on breast cancer risk, we analyzed data from an ongoing, population-based, case-control study of invasive breast cancer in North Carolina. The study population consisted of 498 cases and 473 controls, with approximately equal numbers of African-American and white women, and women under the age of 50 and age 50 years or older. Among premenopausal women, there was no association between current smoking [odds ratio (OR), 0.9; 95% confidence interval (CI), 0.5-1.5] or past smoking (OR, 1.0; 95% CI, 0.6-1.6) and breast cancer risk. Among postmenopausal women, there was also no association with current smoking (OR, 1.2; 95% CI, 0.7-2.0); however, a small increase in risk was observed for past smoking (OR, 1.5; 95% CI, 1.0-2.4). For postmenopausal women who smoked in the past, ORs and 95% CIs were 3.4 (1.4-8.1) for smoking within the past 3 years, 3.0 (1.3-6.7) for smoking 4-9 years ago, and 0.6 (0.3-1.4) for smoking 10-19 years ago. Neither N-acetyltransferase 1 (NAT1) nor N-acetyltransferase 2 (NAT2) genotype alone was associated with increased breast cancer risk. There was little evidence for modification of smoking effects according to genotype, except among postmenopausal women. Among postmenopausal women, ORs for smoking within the past 3 years were greater for women with the NAT1*10 genotype (OR, 9.0; 95% CI, 1.9-41.8) than NAT1-non*10 (OR, 2.5; 95% CI, 0.9-7.2) and greater for NAT2-rapid genotype (OR, 7.4; 95% CI, 1.6-32.6) than NAT2-slow (OR, 2.8; 95% CI, 0.4-8.0). Future studies of NAT genotypes and breast cancer should investigate the effects of environmental tobacco smoke, diet, and other exposures.     

Circulating concentrations of insulin-like growth factor-I and risk of breast cancer

BACKGROUND: Insulin-like growth factor (IGF)-I, a mitogenic and antiapoptotic peptide, can affect the proliferation of breast epithelial cells, and is thought to have a role in breast cancer. We hypothesised that high circulating IGF-I concentrations would be associated with an increased risk of breast cancer. METHODS: We carried out a nested case-control study within the prospective Nurses' Health Study cohort. Plasma concentrations of IGF-I and IGF binding protein 3 (IGFBP-3) were measured in blood samples collected in 1989-90. We identified 397 women who had a diagnosis of breast cancer after this date and 620 age-matched controls. IGF-I concentrations were compared by logistic regression with adjustment for other breast-cancer risk factors. FINDINGS: There was no association between IGF-I concentrations and breast-cancer risk among the whole study group. In postmenopausal women there was no association between IGF-I concentrations and breast-cancer risk (top vs bottom quintile of IGF-I, relative risk 0.85 [95% CI 0.53-1.39]). The relative risk of breast cancer among premenopausal women by IGF-I concentration (top vs bottom tertile) was 2.33 (1.06-5.16; p for trend 0.08). Among premenopausal women less than 50 years old at the time of blood collection, the relative risk was 4.58 (1.75-12.0; p for trend 0.02). After further adjustment for plasma IGFBP-3 concentrations these relative risks were 2.88 and 7.28, respectively. INTERPRETATION: A positive relation between circulating IGF-I concentration and risk of breast cancer was found among premenopausal but not postmenopausal women. Plasma IGF-I concentrations may be useful in the identification of women at high risk of breast cancer and in the development of risk reduction strategies. Additional larger studies of this association among premenopausal women are needed to provide more precise estimates of effect.     

Genetic polymorphisms in catechol-O-methyltransferase, menopausal status, and breast cancer risk

Polymorphic catechol-O-methyltransferase (COMT) catalyzes the O-methylation of estrogen catechols. In a case-control study, we evaluated the association of the low-activity allele (COMT(Met)) with breast cancer risk. Compared to women with COMT(Val/Val), COMT(Met/Met) was associated with an increased risk among premenopausal women [odds ratio (OR), 2.1; confidence interval (CI), 1.4-4.3] but was inversely associated with postmenopausal risk (OR, 0.4; CI, 0.2-0.7). The association of risk with at least one low-activity COMT(Met) allele was strongest among the heaviest premenopausal women (OR, 5.7; CI, 1.1-30.1) and among the leanest postmenopausal women (OR, 0.3; CI, 0.1-0.7), suggesting that COMT, mediated by body mass index, may be playing differential roles in human breast carcinogenesis, dependent upon menopausal status.     

Alcohol consumption and risk of breast cancer: a multicentre Italian case-control study

The relationship between alcohol consumption and breast cancer risk was investigated using data from a co-operative case-control study conducted in Italy between 1991 and 1994 on 2569 incident, histologically confirmed breast cancer cases and 2588 controls in hospital for acute, non-neoplastic, non-hormone related conditions. Overall, 915 (38%) cases and 1048 (43%) controls were abstainers. Compared with them, the odds ratio (OR), adjusted only for age, was 1.31 (95% confidence interval (CI) 1.13-1.53) for drinkers and became 1.39 (95% CI 1.(1)21-1.60) after correction for measurement error. The multivariate OR was 1.21 for drinkers of < or = 5.87 g/day and 1.23, 1.19, 1.21, 1.41 for drinkers of 5.88-13.40, 13.41-24.55, 24.56-27.60, > 27.60 g/day, respectively. The trend in risk was significant (chi 2 = 12.28, P < 0.0005). The association was apparently stronger in premenopausal women (OR = 1.80 for > 27.60 g/day). Considering the different types of alcoholic beverages (wine, beer, digestives, grappa and other spirits), a significant direct trend in breast cancer risk was seen for wine with an OR of 1.27 (95% CI 1.06-1.53) for the category > 26.34 g/day. The ORs were also above unity for beer, grappa, digestives and spirits drinkers. No appreciable interaction was observed between alcohol drinking and body mass index, smoking, or any other covariate considered. Thus, the present data, based on a validated alcohol consumption questionnaire and on a population characterised by a relatively high alcohol consumption in women, confirmed that alcohol drinking is moderately related to breast cancer risk. If causal, this association could explain 12% (95% CI, 5-19%) of breast cancers in Italy, thus representing one of the major avoidable risk factor for breast cancer.     

Hormone replacement therapy, other reproductive variables and symptomatic hip osteoarthritis in elderly white women: a case-control study

BACKGROUND: Recent epidemiological studies suggest that post-menopausal hormone replacement therapy might reduce the risk of hip osteoarthritis (OA) in women. However, the association of the disorder with other reproductive variables is controversial. We addressed this issue in a population-based case control study among 413 female cases and 413 age- and sex-matched controls. METHODS: A total of 413 women listed for hip replacement because of primary OA over an 18 month period were compared with an equal number of controls selected from the general population and individually matched for age and general practice. Information about reproductive variables was obtained by questionnaire administered at interview. RESULTS: The risk of hip OA was significantly elevated among women who had had an oophorectomy (OR = 1.9, 95% CI 1.0-3.7). After adjustment for body mass index, the presence of Heberden's nodes, previous hip injury and past leisure sporting activity (all independent risk factors for hip OA), and for other reproductive variables, there was a non-significant, protective effect of long-term hormone replacement therapy, such that > or =5 yr of use was associated with a 40% reduction in risk (OR = 0.6, 95% CI 0.2-1.8). Paradoxically, short-term HRT use (up to 5 yr duration) was associated with an excess risk of hip OA (OR = 1.7, 95% CI 0.9-3.3). There was no association between the risk of hip OA and use of oral contraceptives, parity or hysterectomy. CONCLUSIONS: These data are consistent with previous studies suggesting a protective effect of long-term hormone replacement therapy on the risk of hip OA. By contrast, an elevation of risk in short-term users was demonstrated. Our results also suggest that risk is increased among women who have undergone unilateral or bilateral oophorectomy. Studies are required to investigate the mechanisms underlying these associations.     

A population-based study of contralateral breast cancer following a first primary breast cancer (Washington, United States)

To evaluate predictors of contralateral breast cancer risk, we examined data from a nested case-control study of second primary cancers among a cohort of women in western Washington (United States) diagnosed with breast cancer during 1978 through 1990 and identified through a population-based cancer registry. Cases included all women in the cohort who subsequently developed contralateral breast cancer at least six months after the initial diagnosis, but prior to 1992 (n = 234). Controls were sampled randomly from the cohort, matched to cases on age, stage, and year of initial breast cancer diagnosis. Information on potential risk factors for second primary cancer was obtained through medical record abstractions and physician questionnaires. Women who were postmenopausal due to a bilateral oophorectomy (i.e., a surgical menopause) at initial breast cancer diagnosis had a reduction in contralateral breast cancer risk compared with premenopausal women (matched odds ratio [mOR] = 0.25, 95 percent confidence interval [CI] = 0.09-0.68), whereas no reduction in risk was noted among postmenopausal women who had had a natural menopause (mOR = 0.90, CI = 0.39-2.09). Among postmenopausal women, there was a suggestion of a lower risk associated with relatively high parity (2+). A family history of breast cancer was associated with an increased risk (mOR = 1.96, CI = 1.22-5.15) and varied little by menopausal status. Having an initial tumor with a lobular component (c.f. a ductal histology) was not related strongly to risk (mOR = 1.47, CI = 0.79-2.74). The results of the present and earlier studies argue that we have limited ability to predict the occurrence of a contralateral breast tumor. Better predictors will be required before diagnostic and preventive interventions can be targeted to subgroups of patients with unilateral breast cancer.     

Breast cancer among women exposed to polybrominated biphenyls

We conducted a nested case-control study with 1,925 women enrolled in a polybrominated biphenyl (PBB) registry to examine the association between breast cancer and serum PBBs. Twenty women who developed breast cancer were matched to 290 control subjects on sex, race, and age. Women with serum PBB levels of 2.0-3.0 parts per billion (ppb) [odds ratio (OR) = 3.5; 95% confidence interval (CI) = 0.9-13] or 4.0 ppb or greater (OR = 3.1; 95% CI = 0.8-12) had a higher estimated risk for breast cancer than women with less than 2.0 ppb. The odds ratios were unchanged when available breast cancer risk factors were included in the analysis.     

Do urinary oestrogen metabolites predict breast cancer? Guernsey III cohort follow-up

This is the first prospective study of urinary measures of the two major competing pathways of oestrogen metabolism, 16alpha-hydroxyoestrone (16alpha-OHE1) and 2-hydroxyoestrone (2-OHE1), in relation to incident breast cancer risk. Experimental and case-control study results suggest that metabolism favouring the more oestrogenic 16alpha-OHE1 pathway may be linked to higher breast cancer risk. Women aged 35 and older from Guernsey (n = 5104) were surveyed in 1977-85 and have been continuously monitored for breast cancer and mortality up to the present (Guernsey III, Imperial Cancer Research Fund). Incident cases of breast cancer were matched to three control subjects for comparison of urinary oestrogen metabolite levels measured by enzyme immunoassay (EIA) in spot urine samples collected at baseline and stored frozen for up to 19 years. Consistent with case-control study results, post-menopausal (but not premenopausal) women at baseline who went on to develop breast cancer showed about a 15% lower 2:16alpha-OHE1 ratio than matched control subjects. Further, subjects with metabolite ratios in the highest tertile of 2:16alpha-OHE1 had about a 30% lower risk than women with ratios in the lowest two-thirds, although results were not statistically significant (OR = 0.71, 95% CI = 0.29-1.75). It is of potential importance that, in contrast to most risk factors for breast cancer, such as late age at first birth, oestrogen metabolism appears to be modifiable via diet and exercise, offering women the possibility of lowering breast cancer risk through non-pharmacological measures, although this remains to be tested.     

Evaluation of an immunoturbidimetric assay for haemoglobin A1c on a Cobas Mira S analyser

A case-control study was carried out in Spain to assess associations between parity, lactation and age at first full-term pregnancy and breast cancer. From November 1989 to February 1992, 184 incident breast cancer histologically confirmed cases were interviewed and matched by age and residence to 184 hospitalized patients and 184 community controls selected by random digit dialing. Multiple logistic regression was used to assess the independent influence of each factor on the risk of breast cancer in relation to other factors included in the model. Age at first full-term pregnancy was associated with breast cancer risk with an estimated odds ratio of 3.5 (95% CI 1.41-9.83) for women with their first birth after 30 years in comparison with those whose first birth was before age 21. Breast cancer risk decreased with increasing number of full-term pregnancies, OR 0.3 (95% CI 0.16-0.78) for women who had had more than 3 full-term pregnancies in comparison with nulliparous women. Among parous women, the estimated OR for women with more than 3 children was 0.4 (95% CI 0.13-0.81) after allowance for age at first childbirth and lactation. The estimated OR was 2.6 (95% CI 1.4-4.7) for women with a positive history of breast cancer in first-degree relatives. Breast cancer was not associated with total duration of lactation. The study indicates that parity is an independent risk factor associated to breast cancer and that the women with a late age at first full-term pregnancy constitute a high-risk group.     

Influence of socioeconomic and cultural factors on racial differences in late-stage presentation of breast cancer

CONTEXT: Breast cancer mortality is higher among African American women than among white women in the United States, but the reasons for the racial difference are not known. OBJECTIVE: To evaluate the influence of socioeconomic and cultural factors on the racial difference in breast cancer stage at diagnosis. DESIGN: Case-control study of patients diagnosed as having breast cancer at the University Medical Center of Eastern Carolina from 1985 through 1992. SETTING: The major health care facility for 2 rural counties in eastern North Carolina. SUBJECTS: Five hundred forty of 743 patients with newly diagnosed breast cancer and 414 control women from the community matched by age, race, and area of residence. MAIN OUTCOME MEASURES: Breast cancer stage at diagnosis. RESULTS: Of the 540 patients, 94 (17.4%) presented with TNM stage III or IV disease. The following demographic and socioeconomic factors were significant predictors of advanced stage: being African American (odds ratio [OR], 3.0; 95% confidence interval [CI], 1.9-4.7); having low income (OR, 3.7; 95% CI, 2.1-6.5); never having been married (OR, 2.9; 95% CI, 1.4-5.9); having no private health insurance (OR, 2.5; 95% CI, 1.6-4.0); delaying seeing a physician because of money (OR, 1.6; 95% CI, 1.1-2.5); or lacking transportation (OR, 2.0; 95% CI, 1.2-3.6). Univariate analysis also revealed a large number of cultural beliefs to be significant predictors. Examples include the following beliefs: air causes a cancer to spread (OR, 2.8; 95% CI, 1.8-4.3); the devil can cause a person to get cancer (OR, 2.1; 95% CI, 1.2-3.5); women who have breast surgery are no longer attractive to men (OR, 1.9; 95% CI, 1.1-3.5); and chiropractic is an effective treatment for breast cancer (OR, 2.4; 95% CI, 1.4-4.4). When the demographic and socioeconomic variables were included in a multivariate logistic regression model, the OR for late stage among African Americans decreased to 1.8 (95% CI, 1.1 -3.2) compared with 3.0 (95% CI, 1.9-4.7) for race alone. However, when the belief measures were included with the demographic and socioeconomic variables, the OR for late stage among African Americans decreased further to 1.2 (95% CI, 0.6-2.5). CONCLUSIONS: Socioeconomic factors alone were not sufficient to explain the dramatic effect of race on breast cancer stage; however, socioeconomic variables in conjunction with cultural beliefs and attitudes could largely account for the observed effect.     

Use of screening mammography and its demographic and risk determinants in women 25 to 65 years of age

BACKGROUND: To know the utilization of the screening mammography among women from 25 to 65 years old in an urban health zone, where there is not an specific screening program for breast cancer. To detect the demographic and risk determinants that are involved in the mammography screening use. SUBJECTS AND METHODS: A sample of 1,240 women were interviewed consecutively as they visited their physician. Risk factors, sociodemographic variables and use of health services were analyzed. The associated variables with the use of mammography screening were determined by univariant analysis. A multiple logistic regression model was designed to identify the variables independently associated with the use of mammography screening. RESULTS: The percentage of interviewed women who have completed at least one mammography screening in the last three years has been 10.2 +/- 3% (confidence level: 95%), 68.3% of them were under 50 years old. The variables independently associated with the use of mammography screening were: age (OR = 1.08); routine visit to the gynecologist (OR = 8.13); educational level (primary: OR = 2.44, secondary: OR = 3.66, university: OR = 7.43, no schooling: reference level); and knowledge about the benefits of mammography screening (OR = 6.15). Family history of breast cancer and the other risk factors were found not to be associated with the use of mammography screening. CONCLUSIONS: The use of mammography screening among women from 25 to 65 years is inadequate according to the age and other risk factors. Mammography screening among women with a family history of breast cancer and those over 50 years old is underused, so it would be recommended and their use increased for these women. But women under 40 years old without family history of breast cancer have to be dissuaded from undertaking such a screening.     

Immunohistochemical detection of c-erbB-2 and p53 in benign breast disease and breast cancer risk

BACKGROUND: We studied the associations between c-erbB-2 protein overexpression and p53 protein accumulation in benign breast tissue and the risk of subsequent breast cancer. METHODS: We conducted a case-control study nested within the cohort of 4888 women in the National Breast Screening Study (NBSS) who were diagnosed with benign breast disease during active follow-up. Case subjects were the women who subsequently developed breast cancer (ductal carcinoma in situ [DCIS] or invasive carcinoma). Control subjects were matched to each case subject on NBSS study arm, screening center, year of birth, and age at diagnosis of benign breast disease. Histologic sections of benign and cancerous breast tissues were analyzed immunohistochemically. Information on potential confounding factors was obtained by use of a self-administered lifestyle questionnaire. RESULTS: Accumulation of p53 protein was associated with an increased risk of progression to breast cancer (adjusted odds ratio [OR] = 2.55; 95% confidence interval [CI] = 1.01-6.40), whereas c-erbB-2 protein overexpression was not (adjusted OR = 0.65; 95% CI = 0.27-1.53). The findings for c-erbB-2 and p53 did not differ among strata defined by menopausal status, allocation within the NBSS, history of breast disease, and whether the benign breast disease was detected at a scheduled screen or between screens. The results were also similar after exclusion of case subjects whose diagnosis of breast cancer occurred within 1 year of their diagnosis of benign breast disease and after exclusion of subjects with DCIS. CONCLUSIONS: p53 protein accumulation, but not c-erbB-2 protein overexpression, appears to be associated with an increased risk of progression to breast cancer in women with benign breast disease.     

Risk factors for contralateral breast cancer in Chennai (Madras), India

BACKGROUND: This is the first cohort study conducted in India to identify risk factors for contralateral breast cancer (CBC) among patients with first primary breast cancer. METHODS: Patients with first primary breast cancer diagnosed in 1960-1989 at the Cancer Institute (WIA) in Chennai, India, were followed-up until 31 December 1994. The risk of CBC was assessed among unilateral breast cancer (UBC) patients who survived for >12 months following the diagnosis of breast cancer and did not develop a second cancer (n = 2665) and among those who developed a CBC > or =12 months after the diagnosis of breast cancer (n = 39). RESULTS: The age-adjusted incidence of CBC among women with UBC was seven times the incidence (per single breast) in the general population. Among women with UBC the relative risk (RR) was 4.5 (95% CI: 1.1-19.6) comparing those with and without a history of breast cancer in the mother, and 2.8 (95% CI: 1.2-6.7) comparing age at first birth 21-25 versus earlier. The RR was 0.3 (95% CI: 0.1-0.6) comparing those with and without hormone therapy for their UBC. Radiotherapy for the UBC had no significant effect on the incidence of CBC. CONCLUSION: Positive family history of breast cancer and later age at first childbirth emerged as stronger risk factors for CBC than UBC. Hormone therapy reduces the risk of CBC.     

Cellular glutathione peroxidase is the mediator of body selenium to protect against paraquat lethality in transgenic mice

A case-control study was conducted between 1992 and 1996 in six Italian areas. It included 537 women with colon cancer, 291 women with rectal cancer and 2081 control women in hospital for acute conditions, unrelated to hormonal or gynaecological diseases. A higher age at menopause was associated with increased colon cancer risk (odds ratio (OR) for > or = 53 years compared with < 50 years = 1.39, 95% confidence interval (CI) 1.04-1.87). Among parous women, a significant trend of decreasing colon cancer risk with increasing number of births was seen for colon (OR for > or = 4 births compared with 1 birth = 0.62, 95% CI 0.42-0.90), but not for rectal cancer. Nulliparous women, however, were at lower risk than women with a single birth, and age at first birth was directly associated with risk. While oral contraceptive use showed no significant influence, ever users of hormone replacement therapy had a reduced risk of rectal cancer (OR = 0.56, 95% CI 0.31-1.01). Thus, the association of colorectal cancer with reproductive and menstrual factors is neither strong nor consistent.