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

Leptin reflects the amount of energy stores, regulates energy balance and is associated with circulating levels of reproductive hormones and insulin-like growth factor-I (IGF-I). Breast cancer has also been associated with obesity, reproductive hormones and circulating IGF-I levels. To determine whether leptin is involved in the etiology of breast cancer, we compared serum leptin levels in 83 cases of pre-menopausal carcinoma in situ of the breast and 69 healthy controls recruited in Massachusetts. Serum leptin levels were 13.69 + 1.3 ng/ml in cases and 16.03 + 1.7 ng/ml in controls. Data were also analyzed using multiple logistic regression with adjustment for known risk factors for the development of breast cancer as well as anthropometric, demographic and hormonal variables, including estradiol, prolactin, IGF-I and IGF-binding protein-3. Odds ratios were 1.75 (95% CI, 0.73-4.21) for the second control-defined tertile and 1.54 (0.46-5.16) for the third control-defined tertile relative to the first. Thus, leptin does not appear to increase the risk of pre-menopausal breast cancer in situ substantially.
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PMID:Leptin in relation to carcinoma in situ of the breast: a study of pre-menopausal cases and controls. 993 51

This study was conducted to assess the relation between body size and risk of breast cancer among young women. A case-control study was conducted among women aged 21-45 years living in three counties in Washington State. Cases were women born after 1944 with invasive or in situ breast cancer that was diagnosed between January 1, 1983, and April 30, 1990. Controls were selected using random digit dialing and were frequency-matched to cases on the basis of age and county of residence. Interviews took place between 1986 and 1992. Body size was evaluated using indices from several different time periods. After adjustment for confounders, a decreased risk of breast cancer was found for women in the highest quintile of body mass index (weight (kg)/height (m)2) as compared with the lowest quintile (for maximum lifetime body mass index, odds ratio = 0.69, 95% confidence interval (CI) 0.51-0.94). Age modified the relation between body size and risk of breast cancer. The odds ratio for women in the highest quintile of maximum body mass index who were aged 21-35 years was 0.29 (95% CI 0.16-0.55), as compared with an odds ratio of 1.5 for women aged 36-45 years (95% CI 0.9-2.5) (p for interaction = 0.003). This study supports prior research showing a decreased risk of breast cancer associated with increased body size among premenopausal or young women. More detailed analysis in this study found a strong effect that was limited to the youngest age group (< or = 35 years).
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PMID:Relation between obesity and breast cancer in young women. 1002 76

To examine the effect of cancer histopathology on the relationship between estrogen-replacement therapy (ERT) use and breast cancer risk, we performed a case-control study of 109 postmenopausal women 45 years or older with in situ or invasive breast cancer matched to 545 controls. When in situ and invasive tumors were combined, the overall odds ratio (OR) describing the association between ERT use and breast cancer risk was not statistically significantly elevated (adjusted OR = 1.48, 95% confidence interval [CI] = 0.89-2.47). When the analyses were confined to women with invasive disease, risk estimates were uniformly higher (adjusted OR = 1.85, 95% CI = 1.00-3.45). In contrast, the overall estimate for the relationship between ERT use and in situ breast cancer was close to 1 (adjusted OR = 1.08, 95% CI = 0.42-2.77). The positive association between ERT use and invasive breast cancer we observed, and the lack of association in women with in situ disease, may represent a distinct biological difference or may be related to the small sample size of our study.
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PMID:Postmenopausal estrogen use and invasive versus in situ breast cancer risk. 1008 20

Gene amplification is one essential mechanism leading to oncogene activation which is supposed to play a major role in the pathogenesis of invasive breast cancer. However, using standard methodologies the detection of gene amplifications has been limited especially in small-sized lesions, like pre-invasive precursor lesions. The combination of two novel technologies, laser-based microdissection and quantitative real-time PCR, facilitates the detection of low-level amplifications in morphologically defined lesions. As a model system we investigated in situ breast cancer (ductal carcinoma in situ, DCIS) classified according to the morphology-based Van Nuys grading system for amplification of growth-regulatory genes. In this study 83 formalin-fixed, paraffin-embedded archival DCIS specimens were examined after laser-based microdissection by quantitative real-time PCR using the TaqMan detection system for amplification of the c-erbB2, topoisomerase IIalpha, c-myc and cyclinD1 gene. In a subset of 17 DCIS with adjacent infiltrating tumour components we compared intraductal and invasive tumour components in parallel for differences in amplification status. The combination of these new techniques represents an excellent tool to gain new insights into carcinogenesis by analyzing genetic alterations in morphologically identified heterogeneous lesions in breast cancer progression within the very same specimen or even tissue slide.
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PMID:Detection of gene amplification in intraductal and infiltrating breast cancer by laser-assisted microdissection and quantitative real-time PCR. 1127 43

Breast cancer is the most commonly diagnosed cancer and the second leading cause of cancer death among Louisiana women. The incidence data from Louisiana Tumor Registry were used to calculate breast cancer incidence rates, which were compared with the combined rates from the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) program. Breast cancer mortality rates for Louisiana were compared with the US death rates from the National Center for Health Statistics (NCHS). Our data revealed that Louisiana women were not at a higher risk for developing breast cancer than women in the SEER areas, but that mortality rates in Louisiana were not correspondingly low. Although the percentage of cases diagnosed at an early stage (in situ and localized) increased in Louisiana from 1988 through 1997, the average in Louisiana was still below the level for the SEER areas (65.9% and 71.6%) in 1993-1997. The rates of in situ breast cancer significantly increased (on average 5.3% for whites per year and 7.1% for blacks), and localized breast cancer also significantly increased (2.6% for whites and 2.5% for blacks), while the incidence of distant stage breast cancer significantly decreased (3.4% for whites and 2.0% for blacks). Compared with white women, black women still were less likely to be diagnosed with early stage breast cancer in 1993-1997 (56.4% and 68.9%). Women residing in the parishes with high percentages of persons in poverty were less likely to be diagnosed with early stage of disease.
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PMID:Breast cancer: incidence, mortality, and early detection in Louisiana, 1988-1997. 1139 31

Recently, there have been studies suggesting that apocrine adenosis of the breast is a putative precancerous lesion, despite the generally held view that apocrine adenosis is benign. Because apocrine adenosis is almost always present as a small area or areas, it cannot be easily studied by conventional methods. In this study, areas of apocrine adenosis were microdissected from archival paraffin-embedded tissue to examine loss of heterozygosity and allelic imbalance compared with normal breast tissue epithelium from the same patients. Seventeen cases of apocrine adenosis, four associated with carcinoma, were analyzed using polymorphic microsatellite markers and polymerase chain reaction for loss of heterozygosity/allelic imbalance at eight loci that were reported to show allele loss or imbalance in invasive and in situ breast cancer. Loss of heterozygosity/allelic imbalance was detected in six of 17 cases of apocrine adenosis; three of 12 (25%) informative cases at 1p (MYCL1), two of seven (28.6%) at 11q (INT2), one of three (33.3%) at 13q (D13S267), two of 12 (16.7%) at 16q (D16S539), and two of 10 (20%) at 17q (D17S250). Neither loss of heterozygosity nor allelic imbalance has been identified at 1p (D1S252), 17p (TP53), or 17p (D17S513). In two of the four cases associated with carcinoma, loss of heterozygosity/allelic imbalance was seen in the same allele as in the synchronous carcinoma. These results suggest that molecular alterations, such as loss of heterozygosity and allelic imbalance, identified in apocrine adenosis may constitute an early event in the pathogenesis of breast cancer; reinforcing the possibility of apocrine adenosis being a putative precancerous lesion.
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PMID:Loss of heterozygosity and allelic imbalance in apocrine adenosis of the breast. 1142 68

Although the risk of breast cancer for women in the United States is approximately 1 in 9, identification of risk factors and translation of that knowledge into strategies for prevention have been inhibited by poor understanding of disease pathogenesis. A few benign breast proliferations are associated with higher risks of breast cancer, but definition of a preneoplastic morphologic continuum is lacking. If progression from a premalignant state to malignancy is accompanied by genetic changes, then identification in benign breast disease lesions (BBD) of alterations similar to those found in breast cancer should strengthen the perception of BBD as a premalignant condition. Current testing for hereditary breast cancer susceptibility presumes that only women with invasive breast or ovarian cancer are gene carriers. Therefore, neither in situ breast cancer nor atypical hyperplasias are considered clinically as evidence of a breast-ovarian syndrome, nor are these diagnoses used to predict carrier status within at-risk families. This reflects lack of evidence that breast cancer develops along a recognized morphologic continuum from precursor lesions. New mutation screening procedures such as DNA microarrays can provide sensitivity, specificity, and high throughput that circumvent limitations imposed on the scope of molecular marker analyses applied to archival resources. We have studied a BRCA1-mutant individual with loss of the wild type BRCA1 allele in benign breast proliferations. Both her benign and malignant lesions showed molecularly identical TP53 mutations, indicating that significant genetic alterations can occur in BBD and supporting the clonal evolution from BBD to malignancy.
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PMID:Establishing a molecular continuum in breast cancer DNA microarrays and benign breast disease. 1177 52

Breast cancer is the commonest cancer among women and the second highest cause of cancer death. It remains a significant health problem and represents a significant worry for many women and their physician. During the last years, intensive research has been focused on accurate risk estimation for breast cancer development. The aim of these efforts is to identify the "high-risk" group of women for breast cancer development. Preventive strategies (including intensive surveillance, chemoprevention, or prophylactic mastectomy) may be applied for the women at high risk for breast cancer development. Given the many management options, it seems reasonable that management of the high-risk woman be tailored to the level of risk she is willing to accept. In estimating the risk for breast cancer development, several factors should be taken into account (including age, reproductive factors, such as age at menarche and age at menopause or pregnancy and age at first live birth, history of benign breast lesions or breast cancer in situ [LCIS/DCIS], prior history of breast cancer, history of familiar or hereditary breast cancer, and environmental and lifestyle factors). Recently, quantitative risk estimation is possible by combining multiple risk factors into a comprehensible risk expression; this is of significant clinical importance, since it will reduce the considerable variation in management among health care providers. The Gail and the Claus model are the most widely used models for quantitative risk estimation. However, the clinician should understand that all models have some limitations that should be recalled as they are applied. It should be emphasized that risk assessment is a serious undertaking and should only be performed by those who have in-depth knowledge about risk factors, family pedigree analysis, comparative statistics, genetics susceptibility testing and the science of probability.
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PMID:Risk estimation for breast cancer development; a clinical perspective. 1202 Jun 73

To evaluate geographical variation of invasive and in situ breast cancer incidence rates using precise geographical coordinates for place of residence at diagnosis, latitude-longitude coordinates pertaining to 10,601 invasive and 1,814 in situ breast cancers for Connecticut women, 1991-95, were linked to US Census information on the 2,905 State census block groups. A spatial scan statistic was used to detect geographic excess or deficits in incidence and test the statistical significance of results, without prior assumptions about the size or location of such areas. The age adjusted invasive cancer incidence rate was 165.3/100,000 women/year. The spatial scan statistic identified 3 places with significantly low incidence rates and 4 places where rates were significantly high. The most probable location of low incidence was rural northeastern Connecticut where risk of disease, relative to elsewhere around the state, was 0.70 (p = 0.0001); the most probable place of elevated incidence was north central Connecticut where a relative risk of 1.34 (p = 0.002) was observed. Incidence of in situ disease was estimated to be significantly high for north central Connecticut (RR = 1.84; p = 0.0001). Geographic differences of invasive and in situ breast cancer incidence were observed. Examining cancer events at the lowest available level of data aggregation is beneficial in highlighting localized rate variations. Such information may enable public health officials to target additional resources for promoting breast cancer screening to specific locations.
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PMID:Geographic differences in invasive and in situ breast cancer incidence according to precise geographic coordinates, Connecticut, 1991-95. 1211 69

A systematic review of radiation therapy trials in several tumour types was performed by The Swedish Council of Technology Assessment in Health Care (SBU). The procedures for evaluation of the scientific literature are described separately (Acta Oncol 2003; 42: 357-365). This synthesis of the literature on radiation therapy for breast cancer is based on data from 29 randomized trials, 6 meta-analyses and 5 retrospective studies. In total, 40 scientific articles are included, involving 41 204 patients. The results were compared with those of a similar overview from 1996 including 285 982 patients. The conclusions reached can be summarized as follows: There is strong evidence for a substantial reduction in locoregional recurrence rate following postmastectomy radiation therapy to the chest wall and the regional nodal areas. There is strong evidence that postmastectomy radiation therapy increases the disease-free survival rate. There are conflicting data regarding the impact of postmastectomy radiotherapy upon overall survival. There is strong evidence that breast cancer specific survival is improved by postmastectomy radiotherapy. There is strong evidence for a decrease in non-breast cancer specific survival after postmastectomy radiotherapy. There is some evidence that overall survival is increased by optimal postmastectomy radiation therapy. There is strong evidence that postmastectomy radiotherapy in addition to surgery and systemic therapy in mainly node-positive patients decreases local recurrence rate and improves survival. There is moderate evidence that the decrease in non-breast cancer specific survival is attributed to cardiovascular disease in irradiated patients. There are conflicting data whether breast conservation surgery plus radiotherapy is comparable to modified radical mastectomy alone in terms of local recurrence rate. There is strong evidence that breast conservation surgery plus radiotherapy is comparable to modified radical mastectomy alone in terms of disease-free survival and overall survival. There is strong evidence that postoperative radiotherapy to the breast following breast conservation surgery results in a statistically and clinically significant reduction of ipsilateral breast recurrences followed by diminished need for salvage mastectomies. There is strong evidence that the omission of postoperative radiotherapy to the breast following breast conservation surgery has no impact on overall survival. In one meta-analysis including three randomized studies a survival advantage is demonstrated by Bayesian statistics. There is strong evidence that the addition of a radiation boost after conventional radiotherapy to the tumour bed after breast conservation surgery significantly decreases the risk of ipsilateral breast recurrences but has no impact on overall survival after short follow-up. There is strong evidence for the use of postoperative radiotherapy to the breast following breast conservation surgery for DCIS (ductal breast cancer in situ). Radiotherapy leads to a clinically and statistically significant reduction of both non-invasive and invasive ipsilateral breast recurrences. There is insufficient evidence to define the optimal integration of systemic adjuvant therapy and postoperative radiotherapy. There are limited data on radiotherapy-related morbidity in breast cancer. No conclusions can be drawn.
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PMID:A systematic overview of radiation therapy effects in breast cancer. 1459 11


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