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

Estrogen receptors (ER) and epidermal growth factor receptors (EGFR) in the tumor cells of breast cancer tissues (primary tumors) and metastatic lymph nodes (involved nodes) were analyzed by immunocytochemical study in 19 patients; 12 were ER positive, and seven were ER negative. Microscopic study was used to determine the percentage of positive cells and the staining index. The percentage of EGFR-positive cells and the EGFR staining index were higher in the ER-negative primary tumors than ER-positive primary tumors. In ER-positive cases, both the number of ER-positive cells and ER content per cell was less in the involved nodes than in the primary tumors, whereas the number of EGFR-positive cells and EGFR content per cell was greater in affected nodes. On the other hand, in the ER-negative cases the number of EGFR-positive cells and EGFR content per cell remain almost unchanged between the primary tumors and involved nodes. The authors supposed a probability, in this study, that estrogen may exert inhibitory action on EGFR production through binding to ER.
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PMID:Comparison of estrogen receptor and epidermal growth factor receptor content of primary and involved nodes in human breast cancer. 206 72

Predisposing factors to cervical cancer development are age, smoking, socioeconomical status, parity, and number of sex partners. Long-term oral contraceptive (OC) use and less than 50 mg estrogen dose have been weakly linked to increased cancer risk. Regular examination and switching to other contraception in case of cervical intraepithelial neoplasia is recommended. Estrogen in sequential pills (Ovacon) increases the risks of uterine cancer by affecting the mucosa. Predisposing factors are: absence of pregnancy (nulliparity), postmenopause, hypertension, and diabetes. Parity reduces the risk. The risk is reduced in combined pills and after use of 1 year. Protection is offered by the progesterone component for 10-20 years after cessation of use. Ovarian cancer is prevented by parity and OC use even 10 years later. High estrogen levels inducing frequent ovulation damage the ovaries. Promoting factors are: old age, avoidance of breast feeding, and overweight. Breast cancer promoters are 1st pregnancy in older age, early menarche, and no pregnancy at all. OC use under age 25 and before 1st pregnancy are significant risk factors. High progesterone levels are associated with increased mitotic activity in the breast. Rare benign fibrocysts can develop into breast cancer. OC use is connected to hepatoma development mainly estrogen-induced. Liver cancer was found twice as high in OC users. Hepatoma often ruptures causing hemorrhage. 8% of liver tumors are malignant with a survival rate of 50% of patients to 4.8 years. The possible association of OCs to skin melanoma and hypophysial tumors could not be confirmed. OCs regulate menstruation, reduce bleeding, protect against uterine and ovarian cancer, but cervical and breast cancers have been influenced by them.
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PMID:[The contraceptive pill and cancer]. 207 68

A new transplantable rat pituitary tumor was induced in F344 female rats with dimethylbenz(a)anthracene and estrogen (MtT/F-DMBA) and studied for 20 serial transplant generations. The tumor grew without estrogen supplements in female rats by the second transplant generation. Sensitivity to estrogens, as indicated by a prolonged latency period for tumor development, was seen at the 20th, but not the 5th transplant generation. MtT/F-DMBA tumors expressed prolactin (PRL), growth hormone (GH), and adrenocorticotropin (ACTH) mRNAs. A decrease in the percentage of cells expressing PRL mRNA, PRL protein, and in the number of secretory granules per cell occurred with serial transplantation. S-100 protein-positive folliculostellate cells were present in the hyperplastic pituitary but not in the transplantable tumors. Estrogen treatment at the 20th transplant generation prolonged the tumor latency period, increased the number of cells expressing PRL mRNA greater than 5-fold by in situ hybridization analysis (14 +/- 2% versus 77 +/- 5%), increased PRL secretion (132 +/- 40 ng/ml versus 3762 +/- 890 ng/ml), and increased the number of cytoplasmic secretory granules per cell. These results indicate that hyperplastic pituitary and true pituitary neoplasms differ in their ability to grow readily after transplantation. The presence of S-100 protein-positive folliculostellate cells, which are present in hyperplastic but not in neoplastic pituitary tissues, may serve as a morphologic marker to separate hyperplastic and neoplastic rat pituitary tissues. Transplantable tumors remained responsive to estrogen with expression of a more differentiated phenotype, including an increased number of cells expressing PRL mRNA and increased numbers of PRL secretory granules.
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PMID:Regulation of prolactin gene expression in a DMBA-estrogen-induced transplantable rat pituitary tumor. 212 15

It is well documented that estrogen influences the growth of mammary carcinoma. Estrogen-induced response of target tissue includes protein-biosynthesis as well as stimulation of cell proliferation. Estrogen stimulates tumor cell proliferation in vitro in a dose-related manner by shortening the cell cycle time primarily at the G1 duration and by increasing the number of dividing cells per cycle. The mechanisms of estrogen action on target cell proliferation are not understood well and because of controversial experimental results the role of functional estrogen receptors in estrogen-induced proliferation is not yet clear. In this work, we studied the effect of estrogen on the growth of cells derived from primary tumors (N = 4) and malignant pleural effusions (N = 6) from patients with histopathologically verified breast cancer. We correlated steroid receptor content of malignant tissue used with results obtained for estrogen-induced cell proliferation. It was shown that there was a positive correlation between steroid receptor content and effect of estrogen on cell proliferation in most of the cases studied (7/10). Our study also confirms the possibility of positive and negative influences of estrogen on modulation of tumor cell growth.
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PMID:[The effect of hormones on tumor growth]. 213 13

Sixty-six female Sprague-Dawley (SD) rats with 7,12-dimethylbenz [alpha] anthracene(DMBA)-induced rat mammary cancer were divided into five groups: tamoxifen (TAM), medroxyprogesterone acetate (MPA), TAM + MPA, ovariectomy (Ovex), control (no treatment). An antitumor effect was shown in each treated group. Thirty-six (72%) out of 50 treated animals responded to the first endocrine therapy. Moreover, tumors disappeared completely from 21 out of the 36 animals, and no new tumors were seen until the 12th week. The facts suggest experimental hormone, when compared to clinical, therapy in DMBA-induced tumors to have a higher response rate. A total of 14 out of 50 tumors failed to respond to the first treatment (resistant tumor). There was no significant difference in the proportion of resistant tumors among the four treated groups. When other endocrine therapies were tried out of resistant tumors, seven out of the 14 responded, the resistant tumors in the TAM group responding significantly well to the other endocrine therapies compared to those in the MPA group (P less than 0.05). These results suggest the possibility of resistant tumors responding to different types of endocrine therapy.
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PMID:Effects of sequential and combined endocrine therapies on the growth of 7,12-dimethylbenz [alpha] anthracene-induced rat mammary carcinoma. 214 26

Twenty-seven cases of cystosarcoma phyllodes (CSP) diagnosed at the Veterans General Hospital, Taipei, were reviewed. Of the twenty-seven cases, seventy per cent were benign, thirty per cent were malignant. One of the malignant cases was transformed from benign one. Of the benign CSPs, one had multifocal lesions and eight were associated with other breast lumps, including fibroadenoma and fibrocystic disease. The mean age of patients with benign CSP was 33 years old, and with malignant CSP, 52 years old. The most frequent location was in upper outer quadrant. We found no positive correlation between tumor size, clinical symptoms, tumor epithelial carcinoembryonic antigen, hypervascularity, mixed mesenchymal components, and benign or malignant CSP. Estrogen and/or progesterone receptors were positive in five benign CSPs detected, but malignant CSP was negative. Variable degrees of epithelial hyperplasia, squamous metaplasia, and apocrine metaplasia, were found in both benign and malignant CSPs. Part of the epithelial component in CSP may be derived from normal breast lobule and duct being trapped into the tumor during tumor infiltration. The mesenchymal differentiation in malignant CSPs include fibrosarcoma, malignant fibrous histiocytoma, liposarcoma, and collision of chondrosarcoma and malignant fibrous histiocytoma. One of the malignant CSPs was found within an old, calcified fibroadenoma. When benign CSP was excised under impression of fibroadenoma, the recurrent rate was 50%. In view of this, we recommend a wide excision for a benign CSP. No axillary lymph node metastasis was detected in malignant CSP, so radical mastectomy was not indicated.
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PMID:[Breast cystosarcoma phyllodes. A clinicopathologic study of twenty-seven cases]. 217 71

We have previously demonstrated that the liver tumor promoter ethinyl estradiol (EE) greatly enhanced the DNA synthetic response of rat hepatocytes in primary culture to epidermal growth factor (EGF). This effect was associated with a 2-fold increase in surface EGF receptor number. In this report, we demonstrate that the increase in cell surface [125I]EGF binding caused by EE is time dependent, beginning at 8 h and reaching a plateau at 18 h. This increased EGF binding was accompanied by a comparable increase in the amount of total EGF receptor protein. In vivo, EE treatment also increased the number of EGF binding sites. EE treatment did not increase the rate of [35S]methionine incorporation into immunoprecipitated EGF receptor protein, nor did it appear to affect the steady-state levels of EGF receptor mRNA compared to that found in controls. However, EE treatment did cause an increase in the half-life of EGF receptor protein from 4.5 +/- 0.5 h in control hepatocytes to 10.4 +/- 1.8 h. Taken together, these results indicate that the EE-induced 2-fold increase in EGF receptor levels, which is associated with the potentiation of responsiveness to EGF, was brought about by stabilization of receptor protein.
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PMID:Regulation of rat hepatocyte epidermal growth factor receptor by the liver tumor promoter ethinyl estradiol. 219 11

This study was done to review critically the experience at the University of California at San Diego in needle localization mammographic biopsy of the breast with regard to use and accuracy in identifying early carcinoma of the breast. Ninety-seven patients underwent needle localization mammographic biopsy of the breast between 1985 and 1987. Indications for this procedure included the presence of microcalcifications or a mass shown on mammographic examination, or both, in conjunction with physical examination which did not define a discrete abnormality in the area. Mammographic, demographic, pathologic, hormone receptor data and staging information were recorded and processed on the MicroVax II computer (Digital Equipment Corporation). Twenty-four per cent of lesions with needle localization mammographic assisted biopsy proved to be malignant. Sixteen lesions were diagnosed as an infiltrating ductal carcinoma and ten of these had an accompanying intraductal carcinoma. Over-all, intraductal carcinoma was present in 16 of the 23 specimens diagnosed as malignant. At biopsy, the margins were clear in 17 of 23, and vascular invasion was present in only one patient with an infiltrating lobular carcinoma. Five were tumor in situ, 12 were stage 1 and five were stage 2 (staging information was not available in one instance). Hormone receptor data were available in 17 of 23 specimens. Estrogen receptors were positive in 13 and progesterone receptors were positive in six. The smallest preinvasive malignant lesion was 4 millimeters, as seen on the mammogram, and the smallest free-standing invasive lesion was 8 millimeters. Preinvasive lesions (intraductal) presented as microcalcifications in 80 per cent. Invasive lesions presented as either a mass (n = 9) or as a mass and microcalcifications (n = 5) in 81 per cent. All five lesions presenting as both a mass and microcalcifications on mammogram proved to be malignant. Multifocal lesions on mammographic examination which proved to be malignant were multifocal pathologically in only 50 per cent. Needle localization mammographic biopsy is useful in detecting early carcinoma of the breast. Biopsy should be done on lesions presenting on mammogram as both a mass and microcalcifications and not observed. Focality of lesions on mammogram does not correlate with focality on biopsy and may be misleading as criteria for operative planning.
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PMID:The predictive value of needle localization mammographically assisted biopsy of the breast. 223 18

Premenopausal breast cancer patients frequently develop amenorrhea during adjuvant chemotherapy. Despite psychic distress and severe weight loss are possible causes for secondary amenorrhea in cancer patients, it is in this case due to the gonadotoxicity of the cytostatic drugs. Alkylating agents, such as cyclophosphamide, damage ovaries directly, resulting in ovarian fibrosis, atretic follicles and decline in estrogen production. Elevated plasma levels of LH and FSH show adequate reaction of the hypothalamohypophyseal unit. There is no change in the androgen production of stromal cells as well as in the plasma levels of prolactin and adrenal androgen precursors. Ovarian damage goes along with hot flushes, loss of libido and dyspareunia. The onset of amenorrhea is age- and dose-related. Commonly the changes are irreversible. Estrogen replacement therapy promptly removes menopausal symptoms but is contra-indicated regarding the possible hormone-dependence of the tumor. In this case low dose medroxy-progesterone acetate is indicated.
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PMID:[Effects of adjuvant chemotherapy of breast cancer on gonadal function]. 223 81

Estrogen (ER) and progesterone (PR) receptors were assayed in the center and the periphery of 24 primary breast cancers and correlated with seven morphological features of the tumors. Quantitative variations in ER and PR contents between center and periphery were not significant, and the major discordance rate of the receptor status was only 8.3% for ER and 12.5% for PR. Among all morphological features studied, only tumor cellularity was correlated with steroid receptors; thus 18 out of 19 ER-positive samples (p less than 0.005) and 15 out of 16 PR-positive samples (p less than 0.025) were tumor cellularity 2-3, and higher ER (p less than 0.003) and PR (p less than 0.007) levels were found in tumor cellularity 2-3. Our results indicate that steroid receptors should be assayed in samples with a high content of tumor cellularity, whether the sample is taken from the center or the periphery of the tumor.
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PMID:Intratumoral variation of estrogen and progesterone receptors in breast cancer: relationship with histopathological characteristics of the tumor. 230 Mar 92


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