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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The measurement of cytoplasmic estrogen receptor in tumors from patients with breast cancer is now well established. Potential uses include prognosis of early recurrence following mastectomy, stratifying patients for adjuvant therapies, and selecting or rejecting endocrine therapy in advanced breast cancer. The use of progesterone receptor measurements to improve our selection process has a good theoretical basis, and early reports now emerging indicate that the presence of both estrogen and progesterone receptor in a breast tumor predicts a high response rate to endocrine therapy. Further work in this area is required, however, since patients with estrogen receptor but not progesterone receptor still have an appreciable response rate.
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PMID:Steroid receptors in human breast cancer. 69 67

Estrogen receptor assays of primary breast tumors have been related to early recurrence of the disease. A significantly longer disease-free interval was found in women whose primary tumor was estrogen receptor positive. Although there was no relationship of receptor content to stage of disease at mastectomy, the greatest difference between recurrence rates was found when the tumor had spread to the lymph nodes, especially to those in the apex of the axilla or in the internal mammary chain. Presence of estrogen receptor is closely related to histologically well-differentiated tumors, but it was found that poorly differentiated estrogen receptor-negative tumors recurred earlier than poorly differentiated receptor-positive tumors and had a very unfavorable prognosis.
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PMID:Estrogen receptor assay in primary breast cancer and early recurrence of the disease. 69 68

The estrogen receptor content of human breast cancer specimens is related to the degree of differentiation (grade) of the tumor. In addition, patients with estrogen receptor-positive tumors experience fewer recurrences and remain disease free for a longer priod of time than do patients with receptor-negative tumors. The presence of estrogen receptor is not correlated with lymph node infiltration.
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PMID:Prognostic value of estrogen receptor determinations in patients with breast cancer. 69 69

Carcinomas of the breast from 352 women were assayed for binding of tritiated estradiol by tumor cytosol with dextran--charcoal adsorption, saturation analysis, and two-point Scatchard plots; the level of saturable binding defined a cytosol as positive or negative for estrogen receptor. Valid assays were obtained on specimens as small as 120 mg. Assays of replicate samples of a cytosol were more reproducible than assays of replicate samples of the tumor itself. Occasional disparity of results between a primary mammary carcinoma and its axillary metastases could be related to differences in tumor cellularity. Saturable binding consistent with the presence of estrogen receptor was found in 59% of 305 primary carcinomas and in 57% of 47 metastatic or recurrent carcinomas. There was a significant negative correlation between the patient's age and saturable estrogen binding in the tumor. Serum estradiol levels of less than 250 pg/ml appeared to have a negligible effect on estrogen receptor content. A small subgroup of high-binding carcinomas had high dissociation constants, but the significance of this observation is not clear.
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PMID:Estrogen receptor assay of carcinomas of the breast by a simplified dextran--charcoal method. 70 34

It is clear that a variety of metastatic deposits can successfully be assayed and found to contain estrogen receptor protein even up to 13 years following the initial tumor surgical procedure. Whether or not the patient has received previous treatment, estrogen receptor status does not appear to be influenced, and biopsies of the 23 metastatic lesions were found to contain estrogen receptors. Fourteen of nineteen patients with metastatic tumors containing estrogen receptors who were treated and evaluated demonstrated remission after hormonal manipulation. Only one patient with a tumor with no estrogen receptors demonstrated tumor regression after hypophysectomy and suggests that a previous response to hormone manipulation may warrant a further trial even when estrogen receptors are not found. The results of estrogen receptor values on metastatic disease of the breasts are extremely valuable in the therapeutic decision making process and should be routinely obtained.
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PMID:Results and merit of estrogen receptor data derived from metastatic tumors of the breast. 71 57

Estrogen receptors (ER) were measured on specimens taken from 27 patients with benign breast conditions and 109 patients with breast cancer. Using sucrose gradient assay, 15% (4/27) of benign lesions and 56% (61/109) of malignant tumors were estrogen receptor-positive (ER-positive means 8S or 8S+4S levels more than 7 fmoles/mg cytosol protein). Progesterone receptors (PR) were tested on specimens from 28 patients and 39% (10/26) of the cancers were PR-positive. ER protein activity was not correlated with stage, histology, size of primary lesions, or extent of axillary or distant metastasis. Tumors with low ER levels are more likely to recur, and recurrent tumors after longer disease-free intervals are more likely to be ER-positive. Detailed analysis showed that ER levels did correlate with age and serum albumin levels. Concentrations of serum alpha1-globulin were decreased, while IgG and IgM were significantly increased among patients with positive ERs. Eighteen evaluable patients with advanced breast cancer had endocrine therapy, 13 had objective response. Twelve of these 13 had 8S receptor above 10 fmoles/mg, or 4S above 15 moles/mg, or 8S+4S above 25 fmoles/mg. The one exceptional patient had tumor with high PR but without detectable ER.
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PMID:Steroid receptors study in breast carcinoma. 74 84

In 318 cases of human primary breast carcinoma, the presence and content of estrogen receptor (ER) have been correlated to histopathological features of these carcinomas. We have evidenced that: a) there is a relationship between the ER presence, the histoprognostic grade and the histological type; b) there is no correlation between the frequency of ER presence, the neoplasic cellularity and the stromal reaction. The presence of ER appears to be related to a differentiated state of the carcinoma and to a moderate neoplasic activity. These data show that ER, correlated with histopathological features, could be used as an estimation's factor of the cellular activity of a human mammary carcinoma, thus as a factor of better prognostic value for the evolution of this tumor.
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PMID:[Human mammary carcinoma: relationship between steroid hormone receptors and histopathology. An hypothesis, the prognostic value of hormone receptors (author's transl)]. 74 96

Several histologic variants of the transplantable R-3327 prostatic adenocarcinoma carried in male Copenhagen rats have been characterized and the histologic types have been correlated with steroid hormone receptor content. One type is clearly an adenocarcinoma; this tumor is hormonally responsive and contains substantial amounts of both androgen and estrogen receptors. In contrast, another histologic type, a fibrosarcoma, is hormonally nonresponsive and does not contain either receptor. A third histologic variant is classified as a carcinosarcoma and contains histological elements of both adenocarcinoma and fibrosarcoma and is also hormonally responsive. This tumor contains lower receptor levels than the adenocarcinomas but more than the fibrosarcomas. The androgen receptor appears to be identical in the different histologic forms of the tumor: the sedimentation coefficient is 7.8S and the dissociatiln constant for methyltrienolone is 4 x 10(-9) M. Similarly, the estrogen receptor from the different histologic forms of the tumor has a sedimentation coefficient of 8.3S and the dissociation constant for estradiol is 7 x 10(-10) M. These findings clearly distinguish the cytosol binding macromolecules from plasma binding proteins, and classify them as steroid hormone receptors. Further, rat serum was devoid of androgen and estrogen binding in the 8S region. Normal prostate tissue from Copenhagen rats contained low levels of an androgen receptor, but no estrogen receptor. It is possible that during growth and/or passage of the R-3327 tumor, the hormonally responsive adenocarcinoma cells do not survive and there is a gradual emergence of the nonresponsive fibrosarcoma. If, as we suspect, the receptors are found in the epithelial cells and not the stromal cells, there clearly should be considerable variation of receptor content in the different intermediary histologic forms of the tumor.
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PMID:Steroid hormone receptor characterization of several histologic variants of a rat prostatic adenocarcinoma. 75 Jul 63

This paper reviews the antiestrogenic and antitumor properties of tamoxifen (NSC-180973; ICI-46474) in the rat. In classic tests for antiestrogenic activity, tamoxifen inhibits the actions of estradiol in the rat uterus and vagina. At the cellular level, tamoxifen inhibits estrogen binding to cytoplasmic estrogen receptors, but although estrogen-receptor units are translocated to the nucleus DNA synthesis does not occur. It is suggested that tamoxifen competes for estrogen receptors in the cytoplasm and the false messenger units block the nuclear acceptors which are normally activated by estradiol-estrogen receptor complexes thereby provoking DNA synthesis. Tamoxifen inhibits the growth of some 7.12-dimethylbenz(a)anthracene-induced rat mammary tumors whereas others continue to grow. Estrogen-stimulated rises in plasma prolactin are only partially inhibited by tamoxifen although at the tumor level, tamoxifen completely blocks estrogen binding. There is a linear correlation (P less than 0.01) between estrogen-receptor levels in tumor biopsies before therapy and tumor responses to 3 weeks of tamoxifen treatment (50 mug/day) i.e., tumors with low levels of estrogen receptors do not respond to therapy whereas tumors with higher levels of estrogen receptors regress. It is suggested that tamoxifen antagonizes the actions of estrogen at the tumor level by blocking the estrogen-receptor mechanism thereby producing tumor regression. Therefore, estrogen-receptor measurements in tumor biopsies before therapy may be a useful predictive test for the tumor response to tamoxifen treatment.
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PMID:Antiestrogenic and antitumor properties of tamoxifen in laboratory animals. 82 17

We have compared the incidence of estrogen receptor (ER) in breast tumors and its clinical correlation with responses to endocrine therapies in Japanese and American patients. There was no correlation between tumor histopathology and the presence of ER, and the ER values in primary and metastatic lesions from the same patients were similar in most Papanese cases. Japanese patients with low and high plasma estradiol levels had identical incidences of ER-positive tumors. The correlation between tumor ER and response to endocrine therapy is similar between Japanese and American patients. The incidence of ER-positive tumors is higher in postmenopausal American patients in both primary and metastatic lesions. It is possible that the reported increase in tumor lymphocyte infiltration in Japanese patients may explain this difference. The reported 5-year survival advantage of Japanese breast cancer patients cannot be explained by differences between the two populations in the response to endocrine therapy for advanced disease.
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PMID:Estrogen receptor and endocrine responsiveness in Japanese versus American breast cancer patients. 83 Mar 99


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