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

The literature indicates that relationships between epidemiologic variables and estrogen receptor activity are not clearly defined. Conflicting and unconfirmed results have been published. Most studies have been based on clinical case series rather than on carefully conducted population-based epidemiologic investigations. In addition, previous reports have not generally considered the potential role of confounding and interaction in the interpretation of the associations reported between estrogen receptor status and risk factors for breast cancer. Given these considerations, the need for further research in this area is obvious. Application of an estrogen receptor scheme (positive vs. negative) for defining breast cancer may allow delineation of cases that may appear quite similar but that represent two different types of disease. Estrogen receptor-positive and estrogen receptor-negative breast cancer behave differently biologically, have different treatment and prognostic implications, and thus may also possibly have different risk factor patterns. Moreover, the extent to which receptor status reflects effects associated with exposure, the disease process, or host influences is not clearly understood. There is some evidence that estrophilin is a biochemical marker of tumor differentiation. Moolgavkar et al. suggested that all breast cancers are initially estrogen receptor-positive, but that as the tumor undergoes clonal evolution and becomes more undifferentiated, the ability to express estrophilin is lost in some cases. If this is true, estrogen receptor results may reflect temporal changes in the biologic characteristics of the tumor as it progresses from a well differentiated to a poorly differentiated state. Receptor status could also reflect changes in host resistance and tumor aggressiveness. This concept is consistent with previous observations that anaplastic, rapidly growing cancers are less likely to be receptor-positive. It has not been established whether estrogen receptor-negative tumors represent an advanced stage of the disease or arise de novo. Clinical studies have failed to demonstrate a relationship between extent of disease at diagnosis and receptor results. Estrophilin concentrations also are apparently not related to stage of disease, lending no support for the notion that receptor level declines with progression of the disease. It is possible that certain etiologic factors lead to the natural selection and growth of receptor-negative cells and that receptor negativity is an early, inherent characteristic of some breast cancers.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Estrogen receptors and breast cancer. 353 84

Estrogen receptor (ER) status and urinary androgen (A) concentration were simultaneously determined in 50 premenopausal patients submitted to bilateral ovariectomy for advanced carcinoma of the breast. When both the hormonal parameters were positive (ER+ A+), the response to castration was favorable in 87.5% of the cases, with a survival rate of 39% at 5 years. No patient responded to the therapy when both the parameters were negative (ER- A-); none of them was alive at 5 years. An intermediate response (more than 50%) and survival rate at 5 years (more than 20%) was obtained in the group of patients with at least one of the two parameters positive (ER+ A-, or ER- A+). These responses were independent of the topography of neoplastic localizations and the length of the disease-free interval.
Breast Cancer Res Treat 1987
PMID:Urinary androgens and tumor estrogen receptor as predictors of ovariectomy response and of survival in advanced breast cancer. 366 55

We have examined the association between hormone receptor concentration in primary breast cancer and the mammographic pattern of the breast in which the cancer arose. A significant association was found between the concentration of estrogen receptor and the proportion of the breast volume occupied by the radiological signs of dysplasia. Both estrogen receptor concentration and dysplasia were found to be strongly associated with age. Estrogen receptor concentration rose with increasing age, while the age of patients with extensive dysplasia was substantially less than that of patients with no dysplasia. After taking age into account, no association remained between estrogen receptor concentration and mammographic dysplasia. Age is therefore a confounding factor in this association.
Breast Cancer Res Treat 1987 Oct
PMID:Age as a confounding factor in the association of mammographic dysplasia and estrogen receptor concentration in breast cancer. 368 83

Identification of preneoplastic lesions of the breast has mainly rested on morphological grounds, supported by epidemiological data. These studies assign a definite precancerous potential to a group of atypical hyperplastic lesions and in situ carcinoma. In spite of much effort no criteria are yet available to understand which, among these lesions, is committed to infiltrative growth, in other words, to understand the risk to a single patient. Estrogens are know to play a critical role in the etiology of breast cancer. The hypothesis is investigated that this role is dependent on a modified expression of their receptor. To approach this question estrogen receptor expression was traced by specific monoclonal anti-receptor antibodies and immunocytochemistry, on a spectrum of breast tissue changes, from normal tissue to infiltrating cancer. Estrogen receptor expression is heterogeneous in normal tissue and in infiltrating cancer, and on the contrary is homogeneous in proliferative atypical lesions and in in situ carcinomas. Present results show that receptor expression is enhanced and becomes homogeneous, maybe constitutive, in atypical hyperplasia and in in situ carcinoma and that this phenomenon could subserve important changes of proliferative capacity which are necessary and possibly sufficient for autonomous growth.
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PMID:Pathophysiology of estrogen receptors in mammary tissue by monoclonal antibodies. 369 78

Estrogen receptor from human breast cancer tissue and from normal human uterus was isolated and characterized by a combination of physical separation methods including ammonium sulfate precipitation, gel permeation chromatography, isoelectric focusing and gel electrophoresis. After incubation with 3H-estradiol-17 beta (3HE2) followed by gel permeation chromatography, specific estrogen-binding activity was found to be present in a 160,000-dalton molecular weight component which had a pI of 7.1-7.3. On polyacrylamide gel electrophoresis this estrogen-binding protein migrated as a single band which could however be dissociated into two subunits with molecular weights of +/- 60,000 and +/- 75,000 daltons. 3HE2 binding was to the 75,000-dalton component.
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PMID:Estrogen receptor from human breast cancer and from normal human uterus: isolation and characterization of similar binding complexes. 372 86

Estrogen receptor (ER) levels were measured in 280 breast cancer patients (mean age 54.5 years). Progesterone receptor (PR) levels were assayed in 101 of them. 61.4% of cases were at stages I and IIa. No significant difference in 2-year survival was established between ER-negative and ER-positive patients (96.7 and 96.0%, respectively). Two-year survival rate and recurrence--free survival for PR-positive cases were significantly higher than those for PR-negative ones (p greater than 0.05).
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PMID:[Steroid hormone receptors and survival in breast cancer patients]. 372 85

Estrogen receptor half-life has been previously estimated to be as great as 5 days in uterine tissue (using protein synthesis inhibitors) and as short as 4 h in MCF-7 breast cancer cells (using dense amino acid incorporation). Using the density shift technique we have demonstrated that the half-life of the estrogen receptor is 2.1 h in primary uterine cell cultures. However, the protein synthesis inhibitors, cycloheximide and puromycin, in conjunction with the density shift technique, block this rapid turnover rate. Presence of steroid does not markedly alter the turnover rate. Dense amino acid incorporation did not appear to alter either the turnover rate or the ability of receptor to undergo ligand-induced transformation.
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PMID:Anomalous behavior of protein synthesis inhibitors on the turnover of the estrogen receptor as measured by density labeling. 375 99

As part of a multi-institutional breast cancer data base, 501 stage I, node negative patients have been followed prospectively with a median of 89 months. Patients were treated by a modified radical mastectomy without postoperative therapy. Estrogen receptor (ER) content of the primary tumor was determined in all cases. For the entire patient group at 10 years, the disease-free survival (DFS) rate is 72% and the overall survival (OS) rate is 85%. Both ER value and race (black versus white) were found to be significant prognostic variables for DFS (p = 0.008 and 0.02, respectively) and for OS (p = 0.0001 and 0.01, respectively). ER positive patients had a better DFS and OS rate compared with ER negative patients (74% versus 66% and 90% versus 68%, respectively). Black patients had significantly worse DFS and OS rates compared with white patients (64% versus 74% and 75% versus 86%, respectively). Statistical interaction between the ER and race variables was apparent when comparing the similar DFS for ER positive white (75%), ER negative white (72%), and ER positive black (73%) patients in contrast to a DFS of less than 42% at 10 years for the ER negative black patients. An analysis of the data for the ER negative black patients suggested that the postmenopausal ER negative black patients are at particularly high risk of recurrence and death from breast cancer.
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PMID:The interaction of estrogen receptor status and race in predicting prognosis for stage I breast cancer patients. 376 86

Breast cancer in males is comparatively rare. A 41-year-old man visited our hospital with a complaint of left breast tumor. Initial examination showed remarkably diffuse metastatic lesions in the lung field and small metastatic lesions in the surrounding skin. Modified radical mastectomy, including the surrounding metastatic skin lesions, and incisional biopsy of the lung were performed. Estrogen receptor was positive in both the primary breast cancer and metastatic cancer lesions in the lung. Postoperative medication of tamoxifen citrate, an estrogen receptor blocking agent, in a dose of 30 mg/day, was given together with fluorouracil, BCG, cyclophosphamide, and methotrexate. No evident change could be seen in the lung field six months after the operation. The metastatic lesions in the lung disappeared two years after the operation when the dose of tamoxifen citrate was increased to 60 mg/day. At this writing, thirty months after the operation, the patient is in good health.
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PMID:Breast cancer in a man treated effectively with a large dose of tamoxifen citrate. 382 Aug 69

Estrogen receptor (ER) was measured in 275 samples from 170 patients with breast cancer by dextran-coated charcoal assay. The results showed that the ER positive rate was 51.2%. The ER status of female patients was not related to age or menopause. The positive rate was lowest in AB blood type. The distribution of positive patients in all types was similar to that reported by Japanese authors. The DNA levels of ER positive cancers were relatively lower than those of negative ones. Pathological examination of cancer tissue indicated that ER positive cancer is well differentiated. The 3 year disease-free rate and 4 year survival rate are both high in ER positive patients than that in the negative patients. Knowledge of ER status is helpful in planning the treatment of breast cancer.
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PMID:[Clinical and pathological characteristics of estrogen receptor-positive breast cancer]. 383 44


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