Proposal to decrease the risk and improve the prognosis of breast cancer

Hormone replacement therapy and breast cancer survival: a systematic review and meta-analysis of observational studies

Previous studies on the association between hormone replacement therapy (HRT) and breast cancer survival have yielded mixed results. We aimed to perform a meta-analysis to assess the association with all available studies. Relevant studies were identified by searching PubMed and EMBASE to April 2017. We calculated the summary hazard ratios (HRs) and 95% confidence intervals (CIs) using random-effects models. The dose-response relationship was assessed by random-effects meta-analysis and dose-response meta-regression models. Forty cohort studies and two case-control studies involving 1,756,833 participants were included. The results showed that prediagnosis HRT use was associated with decreased risk of dying from breast cancer (HR = 0.88, 95% CI 0.81-0.97) or any cause (HR = 0.79, 95% CI 0.69-0.90). Postdiagnosis HRT use also showed a beneficial effect on breast cancer survival. In the subgroup analyses, we found that patients who were current users at diagnosis or who received combined hormone therapy before diagnosis seemed to show more benefit from HRT use. In dose-response analysis, we observed a linear relationship between prediagnosis HRT and breast cancer-specific mortality and a 1-year increment in duration of exposure to HRT conferred an HR of 0.99 (95% CI 0.98-1.00) for death from breast cancer. In conclusion, the average effect of HRT use seems not harmful to breast cancer survival. Nevertheless, this effect of HRT use is needed for further assessment.

Risk of breast cancer associated with hormone replacement therapy

Purpose. The primary objective of this paper is to provide a brief overview of the risk of breast cancer associated with hormone replacement therapy (HRT) in healthy postmenopausal women, in breast cancer survivors, and in women at increased risk for breast cancer.

Data Sources. The literature was reviewed through a MEDLINE search covering the years 1988 to 1999. Relevant articles cited in the literature obtained by MEDLINE searching were also considered. The following terms were searched: estrogen, progesterone, breast cancer, and HRT. The search was restricted to the English language.

Data Extraction. The current literature is reviewed with regard to the risk of breast cancer associated with HRT in healthy postmenopausal women, in breast cancer survivors, and in women at increased risk for breast cancer.

Data Synthesis. HRT is used commonly in post-menopausal women to alleviate both climacteric menopausal symptoms such as hot flashes and urogenital atrophy and to reduce the degree and frequency of osteoporosis. However, exposure to estrogen is one of the most important risk factors for breast cancer, and HRT is a relative contraindication in women with a personal history of breast cancer. The majority of epidemiological literature indicates that healthy women taking short-term HRT are not at increased risk of developing breast cancer. In breast cancer survivors, HRT does not appear to increase the risk of relapse. Some epidemiological studies show that women with a family history of breast cancer are at a substantially increased risk of developing breast cancer when receiving HRT. The decision to use HRT should be made individually by each woman and her health care provider by weighing the expected benefits and potential risks of therapy.

Hormone replacement therapy and the breast

Increasing numbers of women are using hormone replacement therapy (HRT) in their 50s and 60s. Oestrogen alone or oestrogen and progestogen combined given in this age group increase breast density and this has the effect of reducing both the sensitivity and specificity of breast screening in HRT users. HRT significantly increases the risk of developing breast cancer with combinations of oestrogen and progestogens increasing the risk to a greater degree than oestrogen alone. The longer HRT is used the greater the risk with 5 years use being associated with risks of 1.05-1.16 for oestrogen alone and 1.24-1.45 for oestrogen and progestogen combined. No consistent effect of HRT on breast cancer mortality has been demonstrated. Two studies have reported that more than 5 years HRT use is associated with an increased risk of death from breast cancer. A variety of non-oestrogenic agents are available to control menopausal symptoms and these may be of particular value in breast cancer survivors. HRT has been used in breast cancer survivors and although published data are reassuring, none have included sufficient patient numbers to detect small effects of HRT on breast cancer outcome. Prospective randomised trials are underway but are unlikely to include sufficient numbers to exclude a small adverse influence of HRT on breast cancer mortality. Tibolone, a gonadomemetic agent which has been used to control menopausal symptoms, appears to have less direct effects on the breast and is being evaluated as an alternative to oestrogen in breast cancer survivors who develop significant menopausal symptoms resistant to non-hormonal therapies. There is clear evidence that HRT causes breast cancer and the challenge for the physician is to control the menopausal symptoms using HRT or alternatives while at the same time limiting the risks associated with this treatment.

Estrogen replacement therapy in patients with early breast cancer

OBJECTIVE

Most physicians believe that estrogen replacement therapy is contraindicated once a patient is diagnosed with breast cancer. Recently, several studies have shown that estrogen replacement therapy may be safely used in patients with early breast cancer that has been treated successfully. These women can have severe menopausal symptoms and are at risk for osteoporosis. We reviewed the current status of women in our practice with breast cancer who received estrogen replacement therapy, who did not receive hormone replacement therapy, and who did not receive estrogenic hormone replacement therapy.

STUDY DESIGN

The study group consisted of 123 women (mean age, 65.4 +/- 8.85 years) who were diagnosed with breast cancer in our practice, including 69 patients who received estrogen replacement therapy for < or = 32 years after diagnosis. The comparative groups were 22 women who used nonestrogenic hormones for < or = 18 years and 32 women who used no hormones for < or = 12 years. The group who did not receive estrogenic hormone replacement therapy received androgens with or without progestogens (such as megestrol acetate). Of the 63 living hormone users, 56 women are still being treated in our clinic, as are 15 of the 22 subjects who receive nonestrogenic hormone replacement therapy. Follow-up was done through the tumor registry at University Hospital; those patients whose tumor records were not current were contacted by telephone.

RESULTS

There were 18 deaths in the 123 patients: 6 patients who received estrogen replacement therapy (8.69%), 2 patients who received nonestrogenic hormone replacement therapy (9.09%), and 10 patients who received no hormone replacement therapy (31.25%). Of the 18 deaths, 9 deaths were from breast cancer (mortality rate, 7.3%); 3 deaths were from lung cancer; 1 death was from endometrial cancer; 1 death was from myocardial infarction; 1 death was from renal failure; and 3 deaths were from cerebrovascular accidents. The 9 deaths from breast cancer included one patient who received nonestrogenic hormone replacement therapy (mortality rate, 4.5%), 6 patients who received no hormone replacement therapy (mortality rate, 11.3%), and 2 patients who received estrogen replacement therapy (mortality rate, 4.28%). The 9 non-breast cancer deaths included 4 patients who received estrogen replacement therapy (endometrial cancer [1 death], lung cancer [1 death], cerebrovascular accident [1 death], and renal failure [1 death]), 1 patient who did not receive estrogenic hormone replacement therapy group (myocardial infarction), and 4 patients who used no hormones (lung cancer, 2 deaths; stroke, 2 deaths). Carcinoma developed in one patient in the estrogen replacement therapy group in the contralateral breast after 4 years of hormone replacement therapy; she is living and well 2.5 years later with no evidence of disease. Metastatic breast cancer developed in one patient after 8 years of hormone replacement therapy; she is living with disease.

CONCLUSION

Estrogen replacement therapy apparently does not increase either the risk of recurrence or of death in patients with early breast cancer. These patients may be offered estrogen replacement therapy after a full explanation of the benefits, risks, and controversies.

Hereditary Breast Cancer: Risk Assessment Is the Easy Part

Individuals who seek genetic testing to determine hereditary risk of breast cancer may not be aware that genetic testing is uninformative in many high-risk families or that they may be at increased risk of other cancers as well. Many mistakenly believe that current genetic testing provides definitive information about the magnitude of cancer risk to carriers. This article describes the assessment of hereditary risk by pedigree analysis, epidemiology, and genetic testing within the cancer risk assessment and counseling setting, and discusses other information that helps patients to make informed health care decisions. Because the risk of ovarian cancer is increased in many families at high risk of breast cancer, information about prophylactic oophorectomy and hormone replacement therapy is essential. A case history is presented to show the efficacy of cancer risk assessment and counseling when genetic testing is uninformative.

Hormone replacement therapy and breast cancer

There is considerable evidence that the risk of breast cancer is related to ovarian function. However, the effect of postmenopausal hormone replacement therapy (HRT) on breast cancer risk continues to be debated in the absence of data from randomised controlled trials. Observational studies suggest that HRT probably promotes the growth of pre-existing breast cancers rather than initiating malignant transformation of breast epithelial cells but without exerting an obviously detrimental effect on disease-specific mortality. The controversy surrounding HRT and breast cancer has become additionally more complex as a result of the dilemma faced by clinicians advising women rendered oestrogen-deficient by breast cancer therapy. Whilst HRT is currently contra-indicated due to theoretical concerns that it will promote disease recurrence, its increasing, ad hoc prescription to symptomatic breast cancer patients has not been associated with an increase in disease recurrence. Large-scale randomised trials of HRT in healthy women and breast cancer survivors are now ongoing but it will be some years before useful clinical information becomes available. Until then, the limitations and biases implicit as a result of the design of observational studies must be borne in mind when interpreting such studies.

Estrogen replacement therapy in women with previous breast cancer

OBJECTIVE

We sought to review the status of patients with breast cancer who were treated with estrogen replacement therapy and compare the results with those of nonestrogenic hormone users and women not treated with hormone replacement.

STUDY DESIGN

The study group consisted of 76 patients with breast cancer, including 50 using estrogen replacement for up to 32 years, 8 using nonestrogenic hormone replacement for up to 6 years and followed for up to 11 years, and 18 using no hormones for up to 10 years. In addition to estrogen use, 40 of the 50 hormone users were treated with androgens, usually in the form of implantation of testosterone pellets. Forty-five subjects were also given progestogens, usually megestrol acetate 20 to 40 mg for 10 to 25 days each month. The 8 nonestrogen hormone users were treated with various combinations of testosterone pellets, tamoxifen, and progestogens. Forty-two of the 50 estrogen users are still being treated in our clinic, as are 2 of the 8 subjects using nonestrogen hormone. Follow-up was done through the tumor registry at University Hospital, and those whose tumor records were not current were telephoned.

RESULTS

Of the 50 estrogen users, 3 have died (a mortality rate of 6%), and the rest have been followed for 6 months to 32 years, with a mean duration of follow-up of 83.3 +/- 8.81 months. One of the 8 nonestrogen hormone users has died (a mortality rate of 12.5%), and the rest have been followed for 2 to 11 years, with a mean duration of follow-up of 72.0 +/- 5. 93 months. Six of the 18 women not using hormone replacement have died (a mortality rate of 33.3%), and the rest have been followed for 6 months to 10 years, with a mean duration of follow-up of 50.5 +/- 6.01 months.

CONCLUSION

Estrogen replacement therapy apparently does not increase either recurrences or mortality rates. Adding progestogens may even decrease recurrences. Women with early breast cancer should be offered hormone replacement therapy after a full explanation of the benefits, risks, and controversies.

Postmenopausal estrogen replacement therapy is associated with adverse breast cancer prognostic indices

Previous studies have reported that breast cancer patients who used estrogen replacement therapy (ERT) have more favorable tumor characteristics and decreased mortality compared with nonusers. However, these findings may be due partly to increased medical surveillance in ERT users and detection of early stage tumors. Postmenopausal women with biopsy-proven breast cancer (n = 108) were identified based on their participation in screening mammography. Based on self-administered questionnaires completed at the time of mammography, 29 of these were users of ERT. Tumor characteristics (histology size, nodal status, and estrogen receptor content) of ERT users were compared with those of nonusers. After adjusting for potentially confounding variables, the odds ratios (OR) describing the relationship between ERT use and the risk of invasive histopathology (OR = 1.35, 95% CI = 0.48, 3.75), positive nodes (OR = 2.43, 95% CI = 0.59, 10.10), size > or = 2.0 cm (OR = 2.34, CI = 0.66, 8.27), or negative estrogen receptor status (OR = 1.08, 95% CI = 0.18, 9.38) were > 1, although none reached statistical significance. When the subjects were separated into two prognostic groups based on the presence or absence of adverse prognostic indices, ERT users had a statistically significantly increased risk of being in the poor prognostic group (tumor size > or = 2.0 cm or positive nodes or negative estrogen receptor content) (OR = 4.48, 95% CI = 1.10, 18.30). The risk was highest in current users (OR = 6.28, 95% CI = 1.16, 34.00), users for 5 or more years (OR = 7.77, 95% CI = 1.09, 55.60), and users of nonconjugated estrogen (OR = 9.63, 95% CI = 1.18, 78.60). Although our sample size is small and we do not currently have information on long-term outcomes, the findings from this screening population suggest that ERT may have an adverse effect on important breast cancer prognostic indices.

Postmenopausal hormone replacement therapy: effect on diagnosis and outcome in early-stage invasive breast cancer treated with conservative surgery and radiation

PURPOSE

To compare the pretreatment characteristics and outcome of postmenopausal women with stage I-II breast cancer treated with conservative surgery and radiation who had a history of hormone replacement therapy (HRT) with those who had never received HRT.

MATERIALS AND METHODS

From 1979 to 1993, 485 postmenopausal women underwent excisional biopsy, axillary dissection, and radiation for stage I-II breast cancer. The median follow-up was 5.9 years. One hundred forty-one patients reported a history of HRT. The median length of use was 5 years. Three hundred forty-four patients reported no history of HRT.

RESULTS

Statistically significant differences between the two groups were observed for median age (HRT 60 years v no HRT 64 years; P =.0009), median weight (HRT 142 lbs v no HRT 152 lbs; P =.004), clinical tumor size < or = 2 cm (HRT 77% v no HRT 66%; P =.02), and the use of re-excision (HRT 62% v no HRT 49%; P =.01). The method of detection by mammogram only (HRT 52% v no HRT 42%; P =.06) was of borderline statistical significance. The HRT patients had a statistically significant increased cumulative incidence of ipsilateral breast tumor recurrence (8% v 2%; P =.02), a statistically significant decreased cumulative incidence of distant metastases (HRT 6% v no HRT 17%; P =.01), and a borderline statistically significant improvement in cause-specific survival at 10 years (HRT 92% v no HRT 86%; P =.07). Postmenopausal women with a history of HRT did not have an increased risk of contralateral breast cancer or second non-breast cancer malignancy.

CONCLUSION

This study failed to identify an adverse effect of HRT on breast cancer mortality in patients with stage I-II disease treated with conservative surgery and radiation.

Menopause as an issue for women with breast cancer

Menopause is beginning to be recognized as a survivorship issue for women with a diagnosis of breast cancer. This article presents an outline of the literature relating to natural menopause and its symptoms, moves on to discuss general management of menopausal symptoms, then reflects on the particular implications of breast cancer diagnosis and treatment. Finally, the role of nursing in restoring a holistic perspective to the subject of menopause generally, and to women with breast cancer specifically, is considered.

Estrogen replacement therapy and breast cancer survival in a large screening study

BACKGROUND

Hormone replacement therapy has been associated in some studies with reductions in breast cancer mortality among women who develop this disease. It is unclear whether this association reflects the biologic activity of the hormones or the earlier detection of tumors among hormone users. We examined breast cancer mortality among women who were diagnosed with axillary lymph node-negative and node-positive breast cancer according to the currency of estrogen use at diagnosis.

METHODS

Vital status through June 1995 was determined for 2614 patients with postmenopausal breast cancer diagnosed during the period from 1973 to January 1981. We estimated adjusted hazard-rate ratios (adjusting for tumor size, age, race, Quetelet [body mass] index, and number of positive lymph nodes in women with node-positive disease) and unadjusted cumulative probabilities of breast cancer death over time since diagnosis.

RESULTS

Among patients with node-negative disease, rate ratios for breast cancer mortality associated with current use compared with nonuse at diagnosis were 0.5 (95% confidence interval [CI] = 0.3-0.8) until 144 months after diagnosis and 2.2 (95% CI = 0.9-5.2) thereafter. Mortality was not statistically significantly lower in past users. The cumulative probabilities of breast cancer mortality at the end of follow-up were 0.14, 0.14, and 0.09 in nonusers, past users, and current users, respectively. Among women with node-positive disease, the rate ratios associated with current and past use were both 0.5 until 48 months after diagnosis (95% CI = 0.3-0.8 for current users; 95% CI = 0.3-0.9 for past users) and were 1.1 (95% CI = 0.7-1.7) and 1.8 (95% CI = 1.2-2.7), respectively, thereafter. The cumulative probabilities of breast cancer mortality were 0.32, 0.39, and 0.27 in nonusers, past users, and current users, respectively.

CONCLUSIONS

Patients with breast cancer who were using replacement estrogens at the time of diagnosis experienced reductions in breast cancer mortality, which waned with the time since diagnosis.

Physiologic effects of steroid hormones and postmenopausal hormone replacement on the female breast and breast cancer risk

Most data demonstrate that breast cancer is hormonally influenced. For the woman with no history of breast cancer, the benefits of HRT may outweigh the risks. Although it remains the standard of care to discourage hormone use in patients who have had breast cancer, future studies may result in a change of this standard. There needs to be more research into these complex hormonal interactions so that we will have a better understanding of the true risks and benefits when we attempt to advise our patients regarding the best treatment regimens for them.

Impact of menopausal hormone-replacement therapy on clinical and laboratory characteristics of breast cancer

Hormone-replacement therapy (HRT) is widely used by post-menopausal women. Although this treatment may slightly increase the incidence of breast cancer, more and more cases are diagnosed while women are taking HRT. The purpose of this study was to ascertain the influence of HRT on prognostic factors and outcome of breast cancer. Data on all breast-cancer patients, including precise information on HRT, was prospectively and systematically recorded in a data base. From 1985 to 1995, 1379 post-menopausal women fulfilled the eligibility criteria for this study. All were treated by us (P.B. and L.P.) in our ward of a large public hospital of Marseilles, France. The clinical features, laboratory findings and survival rates in 142 HRT users who developed breast cancer while being treated were compared with those of 284 matched never user breast-cancer patients. Patients who developed breast cancer during HRT had fewer locally advanced cancers and smaller and better-differentiated cancers. Lymph-node involvement was significantly less frequent in the user group than in the non-user group (non-significant). Estradiol receptivity was both qualitatively and quantitatively lower in users. There was no significant difference with regard to recurrence and metastasis-free survival and overall survival. We conclude that HRT does not affect the prognosis of breast cancer. Regular surveillance during HRT allows early detection of smaller lesions. The higher number of well-differentiated cancers and the distribution of hormone receptivity may reflect interaction between neoplastic tissue and exogenous hormones.

Hormone replacement therapy in women with previous breast cancer

As breast cancer is known to be a tumour sensitive to the effects of endogenous oestrogens, clinicians are reluctant to prescribe hormone replacement therapy (HRT) to women with a history of previous breast cancer for fear of stimulating disease recurrence, and it is currently contraindicated in this group of women. However, an increasing proportion of breast cancer patients are requesting the use of HRT to relieve the symptoms of oestrogen deficiency, which are also a common side-effect of adjuvant therapy for breast cancer. Observational data on the use of HRT in breast cancer survivors has not demonstrated an increase in disease recurrence, but uncertainty will continue in the absence of data from prospective, randomized trials. This review aims to demonstrate why it is ethical and scientifically important to undertake such studies.

Menopause and post-menopause

From the endocrine point of view, menopause is considered a deficiency state and oestrogen therapy regarded as restoring the pre-menopausal endocrine milieu. Oestrogen therapy alleviates acute climacteric symptoms and also reduces the risk of cardiovascular disease, osteoporosis and Alzheimer's disease. Cardiovascular protection seems to be the major benefit of oestrogen replacement: it reduces morbidity and mortality from coronary heart disease by approximately 50%. The mechanisms are complex and not fully under-stood. In this review we discuss currently available data on the effects of hormone replacement therapy on serum lipids and lipoproteins, the vessel wall (endothelium dependent and endothelium independent), blood flow, cardiac function, blood pressure, haemostasis, insulin sensitivity and direct anti-atherosclerotic effect as possible mechanisms of cardioprotection. Oestrogen therapy reduces the rate of post-menopausal bone loss, increases bone mineral density (BMD) and decreases fracture rate. Recent evidence suggests that initiation of oestrogen therapy in older women produces larger increases in BMD which might provide a significant protective effect at the time when fracture is common. The incidence of Alzheimer's disease is reduced by 50% in post-menopausal women taking oestrogen replacement. Limited clinical trials of oestrogen treatment in women with this disease have documented beneficial effects on cognitive function. The results of epidemiological studies of the effects of oestrogens on breast cancer risk are conflicting but recent evidence suggests that the risk is increased in current users after 5 years of use and among older women. In contrast, increase in the risk of venous thromboembolism is most significant within the first 12 months of therapy, strongly suggesting the importance of individual susceptibility.

Mammographic changes in postmenopausal women on hormonal replacement therapy

The purpose of this study was to investigate the extent of the effects of hormonal replacement therapy (HRT) on the mammographic breast pattern in postmenopausal women. In a hospital-based study mammographic examinations of 81 postmenopausal women were evaluated retrospectively, before and after 1-2 years of treatment with oestrogens or a combination of oestrogens and progestagens. Each individual mammographic film was examined separately, and the glandular tissue was classified according to a modified Wolfe classification. In a screening-centre-based study two consecutive mammograms, with a 2-year interval, of 645 women, of whom 70 were using some kind of hormone therapy, were evaluated retrospectively. In the hospital-based study 31 % of patients treated with combination HRT showed an increase in fibroglandular tissue compared with only 8.7 % in the group treated with oestrogens alone. The difference was statistically significant (p = 0.046). In the screening-based study 14.3 % of the women using hormonal therapy showed an increase, whereas in the non-users no increase was found (p = 1.24 x 10(-10)). After beginning HRT many women (between 14 and 25 % in our experience) can be expected to undergo a mammographically detectable increase in fibroglandular tissue. Radiologists should be aware of the aetiology of such changes, and can obtain information on HRT most conveniently by having the technologist routinely question each patient.

Influence of plasma estrogen levels on the length of the disease-free interval in postmenopausal women with breast cancer

The influence of plasma estrogen levels on disease-free interval (time from primary treatment to first relapse, DFI) in breast cancer patients is not known. Any relation between plasma estrogens and the outcome in breast cancer patients may have implications considering use of hormone replacement therapy (HRT) in patients treated for breast cancer. We measured plasma estradiol (E2), estrone (E1), and estrone sulfate (E1S) in 92 postmenopausal women with breast cancer relapse and correlated plasma estrogen levels to the length of their disease-free interval (DFI1) and the length of the DFI in the subgroup of patients in whom this extended a time period of more than 2 years (DFI2). The length of DFI2 correlated negatively to plasma level of E1S (p < 0.025) and E2 (p < 0.05) and to the E2/E1 and E1S/E1 ratios (p < 0.05), while the length of DFI1 correlated negatively to plasma level of E1S (p < 0.025) and the E1S/E1 ratio (p < 0.005). We also analyzed for possible correlations between DFIs and plasma estrogen levels in subgroups based on tumor stage at diagnosis and previous therapy. In general, these subgroup analyses revealed negative correlations of statistical significance or borderline significance between the DFI1 and DFI2 and E2 and the E2/E1 ratio and non-significant negative correlations between plasma levels of E1S and DFI1 and DFI2. In particular, strong negative correlations between plasma estrogen levels and the length of DFI1 and DFI2 were found among patients responding to first line endocrine treatment for relapse and among patients with primar stage III tumors. Our findings suggest plasma E2 and E1S to stimulate the growth of micrometastases in patients treated for breast cancer.

The effect of hormone replacement therapy on prognostic indices in women with breast cancer

OBJECTIVE

To examine the effect of hormone replacement therapy (HRT) on breast cancer biology.

PATIENTS

Four hundred and sixty Western Australian women with breast cancer who were 40 years or over at the time of their breast cancer surgery.

DESIGN AND SETTING

A questionnaire was sent to women seeking information on the use of HRT before breast cancer surgery. To qualify as HRT users, HRT had to have been used continuously for six months or more up to within two weeks of surgery.

MAIN OUTCOME MEASURES

Biochemical indices of oestrogen receptor, progesterone receptor, cathepsin D and protein levels, and pathological indices of tumour size, tumour differentiation and lymph node involvement for users and nonusers of HRT.

RESULTS

Eighty-seven per cent of questionnaires were recovered and 39 HRT users and 258 non-users were analysed. Twenty-five HRT users used a combination of oestrogen and progestogen and 14 used oestrogen only. Twenty-six had used HRT for more than two years and 13 for two years or less at the time of breast cancer diagnosis. There were no significant differences in the tumour indices between these two groups. The mean level of oestrogen receptors appeared to be lower in oestrogen-only users than in combination HRT users and non-users. The mean cathepsin D level was significantly higher in oestrogen-only users than in non-users. The percentage of all HRT users with involved lymph nodes (23%) was significantly lower than the percentage of non-users (44%).

CONCLUSION

Oestrogen-only HRT may have a detrimental effect on tumour biology. The use of a progestogen in combination with oestrogen may offer some protection. On the other hand, HRT users had less lymph node involvement with tumour. This may reflect early detection with increased surveillance in women using HRT.

Current concepts in estrogen replacement therapy in the menopause

OBJECTIVE

To provide a review of the risks and benefits of hormonal replacement therapy in the menopause, including new therapeutic regimens and modes of delivery.

DESIGN

A review of the literature to identify published studies was accomplished using a computerized bibliographical search (Medline).

RESULTS

Replacement therapy is effective in treating symptoms of estrogen deficiency and in lowering the risk of osteoporosis and cardiovascular disease. The daily administration of an estrogen and progestin eliminates the withdrawal bleed and increases patient compliance. This continuous form of therapy also consistently suppresses the endometrium, decreasing the risk of hyperplasia. More studies investigating the effect of continuous therapy on the lipid profile and cardiovascular disease are needed.

CONCLUSIONS

New therapeutic regimens and modes of delivery decrease risk and increase patient acceptance of hormonal replacement therapy.

Progestins both stimulate and inhibit breast cancer cell cycle progression while increasing expression of transforming growth factor alpha, epidermal growth factor receptor, c-fos, and c-myc genes

This study documents a biphasic change in the rate of cell cycle progression and proliferation of T-47D human breast cancer cells treated with synthetic progestins, consisting of an initial transient acceleration in transit through G1, followed by cell cycle arrest and growth inhibition. Both components of the response were mediated via the progesterone receptor. The data are consistent with a model in which the action of progestins is to accelerate cells already progressing through G1, which are then arrested early in G1 after completing a round of replication, as are cells initially in other phases of the cell cycle. Such acceleration implies that progestins act on genes or gene products which are rate limiting for cell cycle progression. Increased production of epidermal growth factor and transforming growth factor alpha, putative autocrine growth factors in breast cancer cells, does not appear to account for the initial response to progestins, since although the mRNA abundance for these growth factors is rapidly induced by progestins, cells treated with epidermal growth factor or transforming growth factor alpha did not enter S phase until 5 to 6 h later than those stimulated by progestin. The proto-oncogenes c-fos and c-myc were rapidly but transiently induced by progestin treatment, paralleling the well-known response of these genes to mitogenic signals in other cell types. The progestin antagonist RU 486 inhibited progestin regulation of both cell cycle progression and c-myc expression, suggesting that this proto-oncogene may participate in growth modulation by progestins.

Progestins both stimulate and inhibit breast cancer cell cycle progression while increasing expression of transforming growth factor alpha, epidermal growth factor receptor, c-fos, and c-myc genes

This study documents a biphasic change in the rate of cell cycle progression and proliferation of T-47D human breast cancer cells treated with synthetic progestins, consisting of an initial transient acceleration in transit through G1, followed by cell cycle arrest and growth inhibition. Both components of the response were mediated via the progesterone receptor. The data are consistent with a model in which the action of progestins is to accelerate cells already progressing through G1, which are then arrested early in G1 after completing a round of replication, as are cells initially in other phases of the cell cycle. Such acceleration implies that progestins act on genes or gene products which are rate limiting for cell cycle progression. Increased production of epidermal growth factor and transforming growth factor alpha, putative autocrine growth factors in breast cancer cells, does not appear to account for the initial response to progestins, since although the mRNA abundance for these growth factors is rapidly induced by progestins, cells treated with epidermal growth factor or transforming growth factor alpha did not enter S phase until 5 to 6 h later than those stimulated by progestin. The proto-oncogenes c-fos and c-myc were rapidly but transiently induced by progestin treatment, paralleling the well-known response of these genes to mitogenic signals in other cell types. The progestin antagonist RU 486 inhibited progestin regulation of both cell cycle progression and c-myc expression, suggesting that this proto-oncogene may participate in growth modulation by progestins.

Use of the SEER Cancer Registry for technology assessment

The Surveillance, Epidemiology, and End Results (SEER) cancer registry contributed to technology assessment by providing population-based samples for detailed case-control studies, by serving as the control group in comparisons with various experimental groups, by allowing an assessment of selection bias in clinical trials, and by facilitating evaluations of classification and coding systems.

The risk of breast cancer after estrogen and estrogen-progestin replacement

To examine the risk of breast cancer after noncontraceptive treatment with estrogen, we conducted a prospective study of 23,244 women 35 years of age or older who had had estrogen prescriptions filled in the Uppsala region of Sweden. During the follow-up period (mean, 5.7 years) breast cancer developed in 253 women. Compared with other women in the same region, the women in the estrogen cohort had an overall relative risk of breast cancer of 1.1 (95 percent confidence interval, 1.0 to 1.3). The relative risk increased with the duration of estrogen treatment (P = 0.002), reaching 1.7 after nine years (95 percent confidence interval, 1.1 to 2.7). Estradiol (used in 56 percent of the treatment periods in the cohort) was associated with a 1.8-fold increase in risk after more than six years of treatment (95 percent confidence interval, 0.7 to 4.6). No increase in risk was found after the use of conjugated estrogens (used in 22 percent of the treatment periods) or other types, mainly estriols (used in 22 percent of the treatment periods). Although the numbers of women were smaller, the risk of breast cancer was highest among the women who took estrogen and progestin in combination for extended periods. The relative risk was 4.4 (95 percent confidence interval, 0.9 to 22.4) in women who used only this combination for more than six years. Among women who had previously used estrogens alone, the relative risk after three years or more of use of the combination regimen was 2.3 (95 percent confidence interval, 0.7 to 7.8). We conclude that in this cohort, long-term perimenopausal treatment with estrogens (or at least estradiol compounds) seems to be associated with a slightly increased risk of breast cancer, which is not prevented and may even be increased by the addition of progestins.

Benefits and risks of menopausal estrogen and/or progestin hormone use

Current evidence is reviewed here on risks and benefits of estrogen and progestin use by peri- and postmenopausal women in relation to the following conditions: endometrial cancer, breast cancer, osteoporosis, and coronary artery disease (CAD). On balance, estrogen therapy appears to be beneficial for menopausal women, as it probably reduces the risks of CAD and osteoporosis, two of the major causes of mortality and morbidity. Although unopposed estrogen therapy increases the risk of endometrial cancer, that cancer is relatively rare and is not fatal in the vast majority of cases associated with estrogen use. Definitive conclusions about the relation of menopausal estrogens to breast cancer cannot be drawn due to inconsistent evidence to date. Although evidence from randomized controlled trials is lacking, biochemical and clinical evidence suggest that progestin supplementation is associated with a reduction in endometrial cancer risk in women taking menopausal estrogens. Progestin supplementation also may augment the beneficial effects of estrogens in providing protection against osteoporosis, although this effect is not yet well established. There is little direct evidence bearing on the relation of menopausal progestins to breast cancer. Although studies of CAD per se are lacking at present, progestins probably unfavorably alter lipoprotein profiles, thereby increasing a user's risk of CAD. Given the relatively high incidence and mortality of CAD in postmenopausal women, any negative effects on CAD risk could potentially counterbalance beneficial effects on other causes. We conclude that estrogen replacement therapy is of potential benefit to postmenopausal women, but that the question of progestin supplementation requires further study, particularly for CAD risk.

The physiology of the menopause

The decline and eventual cessation of estrogen production by the ovary at menopause are reflected physiologically in tissues with estrogen receptors. The rate of decline of hormones is quite variable and often relates to symptoms experienced. At menopause women still have one third of their life expectancy ahead of them. The physician must determine which symptoms are aging, physiologic changes resulting from estrogen deprivation and which may herald more serious pathology in need of diagnosis and treatment. The knowledgeable physician can give good explanation, which is sometimes as beneficial as medications. Hormone replacement therapy may improve physiologic function of some tissues and relieve symptoms. When hormones are given for clear indications in as safe a method as possible and with adequate monitoring, the woman will have her symptoms relieved and will be grateful for her sense of well-being and ability to enjoy life.

Equine estrogen-dydrogesterone therapy in the management of postmenopausal women

The clinical and metabolic effects of equine estrogen and dydrogesterone combined therapy were investigated in twenty healthy women aged 45 to 59 years with menopausal complaints. Equine estrogens (0.625 mg per day) were given for 2 months, then dydrogesterone (20 mg daily) was cyclically added for 12 days per month, during an additional period of 6 months. The combination was very efficacious in reducing complaints, with a limited number of side effects. Blood pressure, body weight and cervical smears were unaffected. No influence on glucose tolerance, liver or blood coagulation parameters was seen. A VLDL cholesterol decrease of 41% and an increase in apo AI concentrations of 41% was observed. Total, HDL and LDL cholesterol remained almost unaltered, as well as the total:HDL cholesterol ratio. We conclude that the use of the equine estrogen-dydrogesterone combination provides an efficacious, acceptable and probably safe therapy for menopausal complaints.

A review of study findings of the risks and benefits of oestrogen therapy in the female climacteric

A literature review was conducted to assess the evidence regarding the risks and benefits of oestrogen therapy in climacteric women. Consideration was given to the route of administration, effects on lipid levels, the skin and urinary symptoms, endometrial cancer, mortality and replacement therapy. It was concluded from the data examined that properly administered oestrogen treatment does not increase the risk of endometrial cancer and that the relative risk of death in oestrogen users aged over 40 is markedly lower than than in non-users.

Content of low density lipoprotein receptors in breast cancer tissue related to survival of patients

The content of low density lipoprotein (LDL) receptors in tissue from primary breast cancers was determined and its prognostic information compared with that of variables of established prognostic importance. Frozen tumour specimens were selected, and tissue from 72 patients (32 of whom had died) were studied. The LDL receptor content showed an inverse correlation with the survival time. Analysis by a multivariate statistical method showed that the presence of axillary metastasis, content of receptors for oestrogen and LDL, diameter of the tumour, and DNA pattern were all of prognostic value with regard to patient survival. Improved methods of predicting survival time in patients with breast cancer may be of value in the choice of treatment for individual patients.