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Query: UMLS:C0006142 (breast cancer)
 160,383 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Dichlorodiphenyltrichlorethane, a halogenated hydrocarbon, was introduced as an insecticide in the 1940s. In her book "Silent Spring", Rachel Carson expressed her concern for the environment, plants, animals, and human health about the potential harmful effects of such chemicals. In 1972, the Environmental Protection Agency banned the chemical in the USA. DDT and its metabolite DDE are lipid soluble compounds that persist in the environment and bioaccumulate in the body in adipose tissue at levels far higher than those in blood and breast milk. This paper evaluates the possibility of cancer occurring in humans from DDT exposure. Some risk of lymphoma, leukemia, pancreatic cancer, and breast cancer was found in humans exposed to DDT. Animal studies showed a significant association between DDT administration and lymphoma, respiratory cancer, liver cancer, and estrogenic effects on mammary tissue. On the basis of on epidemiological principles, human studies were deficient in adequate sample sizes and were not exempt from such confounding factors as multiple chemical exposure, lifestyle factors, genetic, and other environmental influences. Extrapolation of data on DDT toxicity from animals to humans has limitations. With the persistence of DDT and DDE in the environment, the potential risk to the health of man, animals, and the environment remains.
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PMID:Pesticide exposure: human cancers on the horizon. 1037 19

A nested case-control study was conducted to examine the association between serum concentrations of 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE), the primary metabolite of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT), and polychlorinated biphenyls (PCBs) and the development of breast cancer up to 20 years later. Cases (n = 346) and controls (n = 346) were selected from cohorts of women who donated blood in 1974, 1989, or both, and were matched on age, race, menopausal status, and month and year of blood donation. Analyses were stratified by cohort participation because median DDE and PCB concentrations among the controls were 59 and 147% higher in 1974 than 1989, respectively. Median concentrations of DDE were lower among cases than controls in both time periods [11.7% lower in 1974 (P = 0.06) and 8.6% lower in 1989 (P = 0.41)]. Median concentrations of PCBs were similar among cases and controls [P = 0.21 for 1974 and P = 0.37 for 1989 (Wilcoxon signed rank test)]. The risk of developing breast cancer among women with the highest concentrations of DDE was roughly half that among women with the lowest concentrations, whether based on concentrations in 1974 [odds ratio (OR), 0.50; 95% confidence interval (CI), 0.27-0.89; P(trend) = 0.02] or in 1989 (OR, 0.53; 95% CI, 0.24-1.17; P(trend) = 0.08). The associations between circulating concentrations of PCBs and breast cancer were less pronounced but still in the same direction (1974: OR, 0.68; 95% CI, 0.36-12.9; P(trend) = 0.2; and 1989: OR, 0.73; 95% CI, 0.37-1.46; P(trend) = 0.6). Adjustment for family history of breast cancer, body mass index, age at menarche or first birth, and months of lactation did not materially alter these associations. These associations remained consistent regardless of lactation history and length of the follow-up interval, with the strongest inverse association observed among women diagnosed 16-20 years after blood drawing. Results from this prospective, community-based nested case-control study are reassuring. Even after 20 years of follow-up, exposure to relatively high concentrations of DDE or PCBs showed no evidence of contributing to an increased risk of breast cancer.
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PMID:Serum concentrations of organochlorine compounds and the subsequent development of breast cancer. 1038 43

Dichlorodiphenyldichloroethane (DDE) adipose tissue level has been regarded as a preferred indicator of accumulated human exposure to DDT; however, blood sera are more feasible to obtain and analyze than adipose tissue samples. Inconsistent and scarce information exists in relation to the adipose tissue/serum DDE ratio. As a part of a hospital-based case-control study performed in Mexico City from 1994 to 1996, 198 paired serum and adipose tissue samples were obtained from 72 women with histologically confirmed breast cancer and 126 women with benign breast disease. Both adipose tissue and serum DDE levels were determined by gas-liquid chromatography and reported as ppb lipid weight (ng/g) as well as wet basis (ng/ml). Results showed that the adipose tissue/serum DDE ratio (ADSE) varies according to the type of information (lipid vs wet basis, arithmetic vs geometric means) used for its estimation. ADSE gets a value near 1 (1.1) only when the geometric DDE levels in lipid basis are used for its estimation. The correlation between DDE serum and adipose tissue levels was found (r=0.364, P<0.001). The ADSE did not vary by disease status, nor was it altered by parity, history of breast-feeding, and other reproductive characteristics. We endorse the use of venipuncture instead of biopsy as a way to estimate DDT body burden levels in further research.
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PMID:The adipose tissue to serum dichlorodiphenyldichloroethane (DDE) ratio: some methodological considerations. 1043 45

To explore the role of DDE, the major and most persistent DDT derivative, in cancer etiology, we examined the association of the 1968 adipose DDE levels of population samples from 22 U.S. states with age-adjusted mortality rates between 1975 and 1994 for multiple myeloma; non-Hodgkin lymphoma (NHL); and cancer of the breast, corpus uteri, liver, and pancreas. Separate analyses were conducted by gender and race. Covariates in the regression models included average per-capita income, percent metropolitan residents, and the population density. Liver cancer mortality increased significantly with adipose DDE levels in both sexes among whites, but not among African Americans. No association was observed for pancreatic cancer and multiple myeloma. Breast cancer mortality was inversely correlated with adipose DDE levels among both white and African American women. Significant inverse correlations were also observed for uterine cancer among white women, whereas no association was observed for African Americans and for NHL among whites (men and women) and African American women. The results for pancreatic cancer, multiple myeloma, NHL, breast cancer, and uterine cancer did not support the hypothesis of an association with past adipose levels of the DDT derivative DDE. The multivariate analysis confirmed most findings. The association between liver cancer and DDE observed among whites, particularly in view of the occurrence of hepatic neoplasms in laboratory animals exposed to DDT, warrants further investigation.
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PMID:Cancer mortality and environmental exposure to DDE in the United States. 1062 May 18

Considering the worldwide threat to health and reproduction related to endocrine disruptors (by-products of the chemical industry); considering the untrammelled development of the industrialization and engineering of the living, ethics and gynaecology/obstetrics itself is at a crossroads. Endocrine disruptors (derived from organochlorines and persistent organic pollutants such as PCBs, dioxins and furans, and pesticides such as aldrin, chlordane and DDT), are prime suspects in the deterioration of fertility and intellectual faculties and possibly a key factor in endometriosis, breast cancer and prostate cancer. The long-term and pernicious impacts of endocrine disruptors show our poor understanding of the complexities of life's mechanisms. Paradoxically, with our short-term perspectives and predilection for a technological fix, the problem posed by endocrine disruptors may accelerate the use of reproductive technologies such as ICSI and even cloning, as well as the dissemination of genetically modified organisms. The cure could be worse than the disease. Given the gravity of the challenge to humanity related to the chemical erosion of human health, the mutation of human conception introduced by reproductive technologies and by the drive to genetically modify nature and even human nature, we must urgently re-evaluate the direction in which our societies are headed and the reliance on profit-oriented technology to save us from ourselves. In these circumstances, the collective exercise of wisdom, prudence and responsibility towards the essence and integrity of humanity has become, more than ever, an ethical, and perhaps even a survival, imperative.
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PMID:Will we be taught ethics by our clones? The mutations of the living, from endocrine disruptors to genetics. 1071 12

Some organochlorine compounds may have weak oestrogenic effects and are therefore suspected of increasing the risk of breast cancer. The risk of breast cancer was assessed prospectively in relation to the serum concentration of several organochlorines. In all 240 women, who developed breast cancer between 1976 and 1993 were together with 477 breast cancer-free controls enrolled in a cohort-nested case-control study. The serum dieldrin concentration was associated with a significantly increased dose-related risk of breast cancer (Odds Ratio 2.05; 95% confidence interval 1.17-3.57; p for trend 0.01). There was no overall association between risk of breast cancer and DDT or polychlorinated biphenyls. The results support the hypothesis that exposure to oestrogenic organochlorines may increase the risk of breast cancer.
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PMID:[Organochlorine compounds and breast cancer--is there a connection between environmental pollution and breast cancer?]. 1074 Apr 33

We examined the role of farming and pesticide exposure among 862 cases and 790 controls in a population-based, case-control study of breast cancer conducted in North Carolina between 1993 and 1996. We obtained exposure information through personal interview. Increasing duration of farming was inversely associated with breast cancer risk; odds ratios (95% confidence intervals) were 1.2 (0.8-1.7), 0.8 (0.5-1.2), 0.7 (0.5-1.1), and 0.6 (0.4-0.9) for 1-10, 11-17, 18-23, and >23 years of farming, respectively, relative to nonfarmers. Inverse associations persisted when farming was restricted to calendar time periods of 2,2-bis(p-chlorophenyl)- 1,1,1-trichloroethane (DDT) use or to farming at ages 9-16. Among women who farmed, odds ratios (ORs) were elevated for those who reported being present in fields during or shortly after pesticide application (OR = 1.8, 95% CI = 1.1-2.8) and for those who reported not using protective clothing while applying pesticides (OR = 2.0; 95% CI = 1.0-4.3), but not among those who reported using protective clothing (OR = 0.8; 95% CI = 0.4-1.8). We conclude that residence or work on farms may be associated with a reduced risk of breast cancer. Nevertheless, our results suggest a possible increased risk of breast cancer among a subgroup of farming women who were most likely to be exposed to pesticides.
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PMID:A population-based case-control study of farming and breast cancer in North Carolina. 1095 4

The authors analyzed the relation between lactation history, organochlorine serum levels-in particular, 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane (DDT) and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE)-and the risk of breast cancer within a subsampe from a larger breast cancer case-control study conducted among women living in Mexico City, Mexico, between 1990 and 1995. From the original study, they selected a random sample of 260 subjects (1:1 case/control ratio). Analysis was restricted to 120 cases and 126 controls who had given birth to at least one child and had complete information on all key variables. Serum DDE levels were higher among cases (mean = 3.84 microg/g lipids, standard deviation = 5.98) than among controls (mean = 2.51 microg/g lipids, standard deviation = 1.97). After adjustment for age, age at menarche, duration of lactation, Quetelet index, and serum DDT levels, serum DDE levels were positively related to the risk of breast cancer (adjusted odds ratio (OR)Q1-Q2 = 1.24, 95% confidence interval (CI): 0.50, 3.06; ORQ1-Q3 = 2.31, 95% CI: 0.92, 5.86; ORQ1-Q4 = 3.81, 95% CI: 1.14, 12.80; test of trend, p = 0.02). The increased risk associated with higher serum DDE levels was more apparent among postmenopausal women (ORQ1-Q4 = 5.26, 95% CI: 0.80, 34.30; test of trend p = 0.03). A longer period of lactation was associated with a slightly decreased risk of breast cancer independently of serum DDE levels (OR = 0.91, 95% CI: 0.85, 0.99 change in risk per 10 months of lactation). Serum DDT level was not related to the risk of breast cancer. The data suggest that high levels of exposure to DDE may increase women's risk of breast cancer, particularly among postmenopausal women.
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PMID:Breast cancer, lactation history, and serum organochlorines. 1096 81

A hospital-based case-control study of breast cancer risk related to organochlorine (OC) exposure was conducted in a multiethnic setting in New York City. We enrolled 175 breast cancer patients and 355 control patients. The overall racial/ethnic distribution was 57% Caucasian, 21% Hispanic, 22% African-American; cases and controls were frequency-matched by age and race/ethnicity. Tumor markers (estrogen and progesterone receptors, p53, erbB-2) were assessed and organochlorines (DDE, DDT, trans-nonachlor, and higher (HPCB) and lower (LPCB) chlorinated biphenyls) were measured in blood serum. Tumors among minority women were of slightly higher stage than among Caucasians, but tumor markers were similar across the racial/ethnic groups. DDE levels were highest among African-American and Hispanic women; DDT was highest among Hispanics; HPCBs were highest among African-Americans; LPCBs were lowest among Hispanics; and trans-nonachlor was highest among African-Americans. However, OC levels were not associated with risk for breast cancer, nor did OCs differ with respect to tumor stage or tumor markers. Higher DDE levels were associated with increasing body mass index (BMI), but with decreasing level of education, frequency of nulliparity, and frequency of family history of breast cancer. HPCB levels decreased with BMI and were not correlated with breast cancer risk factors. These relationships can be attributed to historical patterns of exposure and to metabolic differences in OCs related to BMI.
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PMID:Organochlorine exposures and breast cancer risk in New York City women. 1189 71

The environmental organochlorines 2,2-bis(p-chlorophenyl)1,1,1,trichloroethane (DDT) and polychlorinated biphenyls (PCBs) have been implicated as potential causes of female breast cancer. We continued follow-up of our 1997 case-control study nested in the Nurses' Health Study cohort, adding 143 postmenopausal cases and controls to the original 238 pairs, and examining specific PCB congeners for the first time. We measured plasma levels of 2,2-bis(p-chlorophenyl)ethylene (DDE), the major metabolite of DDT, and PCBs prospectively, comparing women who were diagnosed with breast cancer between 1 month and 4 years after blood collection with control women in whom breast cancer did not develop. Median concentrations of lipid-adjusted DDE, total PCBs, and PCB numbers 118, 138, 153 and 180, assessed individually, were similar among the cases and controls. The multivariate relative risk of breast cancer for women in the highest quintile of exposure as compared with women in the lowest quintile was 0.82 for DDE (95% confidence interval [CI]: 0.49-1.37) and 0.84 for total PCBs (95% CI: 0.47-1.52), 0.69 for PCB 118 (95% CI: 0.39-1.22), 0.87 for PCB 138 (95% CI: 0.50-1.50), 0.83 for PCB 153 (95% CI: 0.47-1.48), and 0.98 for PCB 180 (95% CI: 0.55-1.75). Sub-group analyses were also performed. Overall, our results do not support the hypothesis that exposure to DDT and PCBs increases the risk of breast cancer.
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PMID:Plasma organochlorine levels and the risk of breast cancer: an extended follow-up in the Nurses' Health Study. 1125 83


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