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 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The epidemiological and clinical evidence for various forms of exogenous estrogens altering the risk of neoplasms of the female genital system, breast, and liver are reviewed and evaluated. It is virtually certain that in utero exposure to diethylstilbestrol can cause clear cell adenocarcinomas of the vagina and cervix. There is strong evidence that various estrogens given for treatment of menopausal symptoms can cause endometrial carcinoma and that sequential oral contraceptives probably also do so. Oral contraceptives very probably reduce the risk of both cystic disease and fibroadenoma of the breast and increase the risk of liver cell adenomas. Studies to date do not provide consistent and convincing evidence that any form of exogenous estrogen alters the risk of cancers of the breast or ovary or that oral contraceptives alter the risk of cervical neoplasia or focal nodular hyperplasia of the liver, although recent reports suggest that continued vigilance is warranted. Specific topics requiring further epidemiological investigation are suggested.
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PMID:Role of exogenous female hormones in altering the risk of benign and malignant neoplasms in humans. 21 85

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

This editorial consists of summaries of the discussions on incidence, pathogenesis, prognosis and patient follow-up, and transcripts of the discussions on detection and treatment of endometrial carcinoma, from a symposium held in Carefree, Arizona. 75% of the cancers occur in postmenopausal women; average age is 52 years, but is decreasing. Endometrial carcinoma rose from 20.3 to 46.3% of all uterine cancers in Cleveland University Hospitals from 1941-1970. Older patients are often diabetic, overweight, nulliparous, with anovulatory or familial history; young women frequently resemble mild Stein-Levinthal syndrome. Clinically, 20% of patients are assymptomatic, others may have softer or larger uterus, larger ovaries, irregular postmenopausal bleeding, or lengthy onset of menopause. The Gravlee jet wash is indicated for high risk patients and those about to take estrogen. Endometrial carcinoma first affects epithelium, then endometrial stroma, then upper myometrium, lower myometrium, then other organs, perhaps via lymphatics, vagina, tubes, but ascites is uncommon. Generally, U.S. physicians use intrauterine radium followed by surgery, British use surgery first, and Swedish use radiation only. Cases must be treated individually, e.g. surgery only for minimal cancer, radium and surgery for more serious cases, and preoperative external radiation also for advanced disease. Although radiation lessens chance of implantation during surgical trauma, insertion of intrauterine radium enhances spread of tumor cells. Injectable progestins sometimes control metastatic disease, although they require 8 weeks to act. Progestins may help those with late recurrence, squamous metaplasia, or who are under 50 years of age. Estrogens are rarely effective. Prognois for terminal patients often includes subjective improvement, bowel obstruction, lung complications, hemorrhage. Radiation side effects and menopausal symptoms are often problems for cured patients. In young cured patients the endometrium should be suppressed with progestins or oral contraceptives.
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PMID:Endometrial cancer: rising incidence, detection and treatment. 469 33

Among 34,318 participants in a cervical cancer screening program conducted in 12 California counties between 1975 and 1979, biopsy-proved cervical neoplasia was found in 166. These women served as cases in a case-control study to investigate the association of selected characteristics with the risk of cervical dysplasia and/or cancer. A random sample of program participants with only negative cytologic tests formed the control group. The following factors showed no association with cervical neoplasia: ethnic affiliation, age at menarche, age at first marriage, age at first pregnancy, age at birth of first child, mean number of children, and ever use of oral contraceptives. Risk of cervical neoplasia was increased in women who were less than 40 years of age; were of poverty or low income status; and were separated, divorce, or widowed. A decrease in risk was associated with nulliparity, ever use of estrogens for relief of menopausal symptoms, and ever use of the diaphragm.
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PMID:Factors associated wih high and low risk of cervical neoplasia. 693 10

Sex steroids are not known to damage DNA directly. They can stimulate or inhibit cell proliferation, and thus can modulate tumor developmental progression. Sex steroid-related tumors in women are represented by breast cancer and endometrial cancer, and a possible relationship exists between sex steroids and both ovarian and colon cancer. Among current ERT users or those who stopped use 1-4 years previously, the relative risk of having breast cancer diagnosed increases by a factor of 1.023 for each year of hormone use. This increase is comparable with the effect on breast cancer of delaying menopause, and seems to be largely limited to lean women. The breast cancers diagnosed during ERT are more likely to contain ER and are less aggressive. Some reports indicate no increase in breast cancer mortality in HRT users. Recent data suggest that an estrogen-progestin regimen may increase breast cancer risk beyond that associated with estrogen alone. However, the effect of progestogens on the breast awaits further clarification. ERT/HRT is generally considered to be contraindicated in breast cancer patients, as no firm data are yet available from randomized clinical trials. Despite the potential risks, ERT/HRT could be considered for breast cancer patients suffering from menopausal symptoms resistant to alternative treatments, after completely informed consent is given, particularly in women with ER--(hormone-resistant) cancers. Unopposed estrogen therapy is known to increase endometrial cancer risk, and is appropriate only for hysterectomized women. To negate the excess risk of endometrial hyperstimulation, an adequate progestin dose must be given in a continuous combined regimen or for an appropriate number of days in sequential regimens (10 days or more for some progestogens or 12 days or more for other progestogens). An appropriate combination of estrogen and progestin does not appear to increase, and may even decrease, the risk of endometrial cancer. HRT is generally considered to be contraindicated in endometrial cancer patients. Despite the potential risks, HRT could be considered for patients suffering from menopausal symptoms resistant to alternative treatments, after completely informed consent is given. Available data suggest a reduced risk of colorectal adenoma and colon cancer in current users of HRT, but definitive studies are still needed. There is no contraindication to HRT prescription in colon cancer survivors. Consistent epidemiological data describe a decreased incidence of ovarian cancer with oral contraceptive use during the reproductive years. Studies on HRT and risk of epithelial ovarian cancer have produced conflicting results but most data seem to exclude a strong association. While no data contraindicate HRT use in epithelial ovarian cancer survivors, current studies do not allow us to exclude the possibility that estrogens alone could stimulate ovarian cancer growth in a small fraction of patients. Additional studies are required. It is important to consider that not all estrogens and progestins are used with the same dosage, route of administration (oral, transdermal and for estradiol intranasal) and, mostly, different estrogens do not show the same bioavailability and tissue effects. The available data do not allow to discriminate for all these variables and therefore it is inappropriate to consider jointly all forms of hormonal therapy. This issue is considered as an important area for future evaluation and research. The International Menopause Society is in the process of drawing up specific recommendations for further research in the field of HRT and cancer.
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PMID:Controversial issues in climacteric medicine II. Hormone replacement therapy and cancer. International Menopause Society Expert Workshop. 9-12 June 2001, Opera del Duomo, Pisa, Italy. 1158 39

Dietary supplements containing concentrates of plant-derived estrogens are being increasingly used by consumers as alternatives for hormone replacement therapy, for treatment of menopausal symptoms, and as cancer preventives. The effect of dietary genistein on dimethylbenz[a]anthracene (DMBA)-induced mammary tumor development was investigated in wild-type (ER alpha WT) and estrogen receptor-alpha knockout (ER alpha KO) mice. ER alpha WT and ER alpha KO mice were fed a casein-based diet containing 0 or 1 g genistein/kg diet from weaning. Tumors were induced by oral administration of DMBA and subscapular implantation of medroxyprogesterone acetate. No tumors were observed in ER alpha KO mice. In ER alpha WT mice, dietary intake of genistein influenced tumor development, enhancing anaplasia of mammary cancer. Mice consuming genistein expressed malignant mammary adenocarcinoma, whereas benign adenomas were observed in mice fed the control diet. Dietary intake was also influenced by genistein, with ER alpha WT and ER alpha KO mice fed genistein consuming less food (p < 0.0001) and subsequently weighing less than mice fed the control diet (p < 0.0001). Significant differences in food intake by genotype were also observed (p = 0.0017), with ER alpha KO mice consuming less than ER alpha WT mice. Overall, this study found no protective effect of genistein on DMBA-induced mammary tumors in mice and suggests a potential adverse effect on tumor development when high levels of genistein are consumed.
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PMID:Dietary genistein increased DMBA-induced mammary adenocarcinoma in wild-type, but not ER alpha KO, mice. 1175 85

Sex steroids are not known to damage DNA directly. They can stimulate or inhibit cell proliferation, and thus can modulate tumor developmental progression. Sex steroid-related tumors in women are represented by breast cancer and endometrial cancer, and a possible relationship exists between sex steroids and both ovarian and colon cancer. Among current ERT users or those who stopped use 1-4 years previously, the relative risk of having breast cancer diagnosed increases by a factor of 1.023 for each year of hormone use. This increase is comparable with the effect on breast cancer of delaying menopause, and seems to be largely limited to lean women. The breast cancers diagnosed during ERT are more likely to contain ER and are less aggressive. Some reports indicate no increase in breast cancer mortality in HRT users. Recent data suggest that an estrogen-progestin regimen may increase breast cancer risk beyond that associated with estrogen alone. However, the effect of progestogens on the breast awaits further clarification. ERT/HRT is generally considered to be contraindicated in breast cancer patients, as no firm data are yet available from randomized clinical trials. Despite the potential risks, ERT/HRT could be considered for breast cancer patients suffering from menopausal symptoms resistant to alternative treatments, after completely informed consent is given, particularly in women with ER-(hormone-resistant) cancers. Unopposed estrogen therapy is known to increase endometrial cancer risk, and is appropriate only for hysterectomized women. To negate the excess risk of endometrial hyperstimulation, an adequate progestin dose must be given in a continuous combined regimen or for an appropriate number of days in sequential regimens (10 days or more for some progestogens or 12 days or more for other progestogens). An appropriate combination of estrogen and progestin does not appear to increase, and may even decrease, the risk of endometrial cancer. HRT is generally considered to be contraindicated in endometrial cancer patients. Despite the potential risks, HRT could be considered for patients suffering from menopausal symptoms resistant to alternative treatments, after completely informed consent is given. Available data suggest a reduced risk of colorectal adenoma and colon cancer in current users of HRT, but definitive studies are still needed. There is no contraindication to HRT prescription in colon cancer survivors. Consistent epidemiological data describe a decreased incidence of ovarian cancer with oral contraceptive use during the reproductive years. Studies on HRT and risk of epithelial ovarian cancer have produced conflicting results but most data seem to exclude a strong association. While no data contraindicate HRT use in epithelial ovarian cancer survivors, current studies do not allow us to exclude the possibility that estrogens alone could stimulate ovarian cancer growth in a small fraction of patients. Additional studies are required. It is important to consider that not all estrogens and progestins are used with the same dosage, route of administration (oral, transdermal and for estradiol intranasal) and, mostly, different estrogens do not show the same bioavailability and tissue effects. The available data do not allow to discriminate for all these variables and therefore it is inappropriate to consider jointly all forms of hormonal therapy. This issue is considered as an important area for future evaluation and research. The International Menopause Society is in the process of drawing up specific recommendations for further research in the field of HRT and cancer.
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PMID:Hormone replacement therapy and cancer. 1182 70

The mean age of presentation of malignant melanoma in women is the early fifties, a time that may be concomitant with the onset of the menopause. As the lesion can often be successfully surgically excised, many women will enter the menopause disease-free but in need of treatment for their menopausal symptoms. Melanoma has traditionally been considered to be an estrogen receptor-positive tumor, whose prognosis is adversely affected by estrogen, whether during pregnancy or in association with the oral contraceptive pill or hormone replacement therapy (HRT). Recent evidence now refutes this. As most recurrences occur in the first 2 years following treatment, it may be prudent to defer HRT until this time. There is a particular paucity of information pertaining to HRT and melanoma, such that, at present, there appears to be no justification for withholding this potentially beneficial therapy from menopausal women who have undergone treatment for melanoma.
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PMID:Hormone replacement therapy and malignant melanoma: to prescribe or not to prescribe? 1205 Nov 16

Cimicifuga racemosa (CR) is widely used in the treatment of menopausal symptoms. Mechanistic studies suggest that unlike hormone-replacement therapy, CR does not stimulate estrogen-receptor positive breast cancer cells. To evaluate CR safety, we performed an in vivo investigation of a clinically tested isopropanolic CR extract. Mammary tumors were induced in Sprague Dawley rats (n = 75) by the application of 7,12-dimethylbenz[a]anthracene. Five to nine weeks later, the animals were ovariectomized, allowed to recover, and administered daily doses of CR extract (0.714, 7.14, or 71.4 mg/kg body weight per day) or control substances (estrogen/positive control: 450 microg/kg/day mestranol; or CR vehicle/negative control). The animals were sacrificed 6 weeks later, and tumor number, size, plasma hormone levels, and the weight of estrogen-sensitive organs were analyzed. In contrast to mestranol treatment, CR treatment did not stimulate cancerous growth. There were no significant differences in tumor number or size between the CR groups and the vehicle control. Likewise, prolactin, follicle-stimulating hormone, and luteinizing hormone levels and organ weights and endometrial proliferation were unaffected. The lack of mammary tumor-stimulating effects of this extract is of great significance in establishing the safety of CR extracts for treatment of menopausal symptoms in women with a history of breast cancer in which hormone-replacement therapy is contraindicated.
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PMID:Lack of promotion of estrogen-dependent mammary gland tumors in vivo by an isopropanolic Cimicifuga racemosa extract. 1206 87

There is definitely a need for the development of new drugs for the treatment and cure of endometrial cancer. In addition there are various new drugs or phyto-remedies under development which are intended for use in the treatment and prevention of breast cancer, for the treatment of menopausal symptoms and for hormone replacement therapy. The efficacy of novel drugs targeting steroid receptors in endometrial cancers has to be evaluated and the safety of other endocrine measures on endometrial cancers or on endometrial carcinogenesis has to be assessed. For these experimental purposes five main classes of experimental models are available: spontaneous endometrial tumorigenesis models in inbred animals (Donryu rats, DA/Han rats, BDII/Han rats), inoculation tumors from chunks of tumors (rat EnDA-tumor, human EnCa 101 tumor) or from inoculated tumor cell lines (rat RUCA-I cells, human Ishikawa and ECC-1 cells), developmental estrogenic exposure or chemical carcinogen exposure of CD-1 and ICR mice, transgenic approaches such as mice heterozygous regarding the tumor suppressor gene PTEN (pten(+/-)-mice) and endometrial tumor cell lines cultured under conditions promoting in vivo-like morphology and functions e.g. cell culture on reconstituted basement membrane. Although the number of models is comparatively small, most aspects related to functions of estrogenic or gestagenic substances are assessable, particularly if various experimental models are combined. Whereas models based on human endometrial adenocarcinoma cells are widely used, the properties and advantages of animal-derived models have mainly been ignored so far.
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PMID:Endometrial cancer: experimental models useful for studies on molecular aspects of endometrial cancer and carcinogenesis. 1265 69


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