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

Mrs. S's case demonstrates the dilemmas that many women face at menopause regarding HRT. No clear answer to her question exists. Oncology nurses need to help women understand that taking HRT is a decision that is best made after carefully weighing the risks and benefits of therapy. Mrs. S needs to realize that she has some risk factors for heart disease, osteoporosis, breast cancer, and uterine cancer. Depending on her motivation, Mrs. S can modify some of the risk factors (e.g., reducing her weight and cholesterol). Smoking cessation also would reduce her risk for heart disease and, to a lesser extent, osteoporosis. Although her risk for developing breast cancer is higher than for a woman without a family history of breast cancer, she only has one relative who was older when she developed breast cancer. This risk factor in itself probably would not be enough to advise her against taking HRT. Additional testing may offer some clarification. If her breasts are difficult to examine or her mammograms are difficult to interpret, Mrs. S may feel that the risk of missing breast cancer early is too high to justify taking HRT. An abnormal endometrial biopsy also may make Mrs. S decide against taking HRT. BMD testing might help to better assess her risk for osteoporosis. If some bone loss has occurred before menopause, she may want to give more consideration to taking HRT or medications such as alendronate sodium to reduce her risk for an osteoporotic fracture. Women need to understand that, often, no best answer is available to the question of whether or not to take HRT. With every decision comes some consequences. An understanding of risk factors and ways to maximize cardiovascular, breast, endometrial, and bone health are important factors to consider when making an informed decision. Clearly, this is an area where oncology nurses can provide tremendous patient education and support to women making decisions about HRT.
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PMID:Case in point. Counseling about hormone replacement therapy. 959 44

Tamoxifen and toremifene are two mostly used antiestrogens in the treatment of breast cancer. To compare their effect on bone in postmenopausal breast cancer patients we measured the urinary output of two bone resorption markers, pyridinoline (Pyr) and deoxypyridinoline (Dpyr) as well as bone density (BMD) in 30 breast cancer patients using either tamoxifen (20 mg/day, n = 15) or toremifene (40 mg/day, n = 15) as adjuvant treatment of stage II breast cancer for 1 year. The urinary output of Pyr and Dpyr were assessed before and after 6 and 12 months of the antiestrogen regimen. Lumbar and femoral BMD were measured by dual energy X-ray absorptiometry (DXA) before and after 12 months of treatment. Both tamoxifen and toremifene were associated with significant decreases in Pyr (mean fall 19.6% and 12.6%, respectively) and Dpyr (mean fall 21.6% and 15.5%, respectively) at 6 months. After 12 months' treatment, Pyr decreased by 30.8% and Dpyr by 21.2% in women using tamoxifen and significantly less in women using toremifene (10.1% and 4.9%, respectively). BMD in the lumbar spine decreased by 1.8% in the toremifene group but increased by 0.4% in the tamoxifen group; in the proximal femur, BMD increased slightly during both tamoxifen and toremifene treatment in all sites measured. Individual changes in Pyr and Dpyr at 6 months showed no significant relation to the change in BMD at 12 months. We conclude that tamoxifen (20 mg/day) and toremifene (40 mg/day) reduce the bone resorption similarly, and this can be detected by falls in urinary output of Pyr and Dpyr at 6 months of treatment.
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PMID:Effects of tamoxifen and toremifene on urinary excretion of pyridinoline and deoxypyridinoline and bone density in postmenopausal patients with breast cancer. 1054 61

The term "SERM" stands for "Selective Estrogen Receptor Modulators", substances which act on certain organs as oestrogen agonists and on other organs as oestrogen antagonists. They can exert the known oestrogen-like effects on bone and lipids without exerting any action on the endometrium and the breast, a potentially ideal profile for postmenopausal hormone replacement treatment. Long known are clomifen, an ovulation stimulator, and tamoxifen, used for secondary prevention in breast cancer. Tamoxifen prevents postmenopausal bone loss as efficiently as hormone replacement treatment, and lowers blood lipids and the coronary risk, but increases the risk of endometrial cancer; for this reason it cannot be used in the prevention of postmenopausal osteoporosis. Raloxifen stimulates neither the endometrium nor the mammary gland, and probably even lowers the risk of breast cancer. Its relatively mild but significant effect on BMD (+ 2-3%/2 years) is sufficient for prevention, and in osteoporotics goes along with a substantial decrease in vertebral fracture incidence (by about 50%) comparable to the effect of other treatments. As in hormone replacement treatment, thromboembolism and leg cramps occur more frequently. Therefore, raloxifen can be used in women free of climacteric symptoms for the prevention and treatment of postmenopausal osteoporosis with no increased risk of phlebitis, alone or in combination with calcium, vitamin D, bisphosphonates and calcitonin; in future it may also be useful in male osteoporosis.
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PMID:[Selective estrogen receptor modulators (SERM): new substances for hormone replacement therapy]. 1063 85

Alzheimer's disease, CAD, and osteoporosis significantly affect the health and well-being of senior citizens in the United States. The fact that women have a longer life expectancy than men has led to the hypothesis that estrogen in some way imparts protection against these disease processes. Available data on the possible negative effect of estrogen on the development and progression of Alzheimer's disease are provocative but inconclusive. Thus, for the time being, they must remain no more than the basis of an attractive hypothesis. In contrast, available data suggest that ERT and HRT can reduce the risk of CAD, but this effect seems more preventive than therapeutic. Addition of a progestational agent to an estrogen regimen may blunt this effect. Although the medical literature contains very few data that address the issue of duration of therapy, logic would suggest that cessation of therapy would result in the loss of a protective effect. With regard to osteoporosis, ERT and HRT have clear beneficial effects in that they increase BMD and decrease fracture risk. There is good evidence that duration of therapy may be more important than dosage and that these effects rapidly dissipate with cessation of therapy. Finally, as with all medical interventions, ERT or HRT must be individualized for each patient. Although actual health hazards are few, adverse effects are common and the emotion-charged, ever-evolving issue of the negative impact of ERT and HRT on breast cancer risk must always be considered before such therapy is instituted.
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PMID:Making a decision about ERT/HRT. Evidence to consider in initiating and continuing protective therapy. 1126 55

Phytoestrogens are non-steroidal plant molecules whose structure differs from gonadal hormones, but with an estrogen-type bioactivity: they are capable of interacting with estrogen receptors, showing both agonist and antagonist methods of action. The beneficial effects of various classes of phytoestrogens present in nature are now known, but the main isoflavone present in soya, genistein, appears to be particularly effective. Interest in this substance is concentrated in particular on its therapeutic role in menopause. This paper is a review of the main studies published to date on the efficacy of phytoestrogens in reducing the symptoms of menopause. A diet rich in isoflavones is associated with a reduced incidence of vasomotor episodes; the average supplement of genistein is approximately 50 mg/day. After supplementing the diet with phytoestrogens, studies show a reduction in total cholesterol and LDL fraction. This is accompanied by an increase in BMD (Bone mineral density) after taking 90 mg of isoflavones for 6 months. Isoflavones may reduce the risk of developing breast cancer. The data examined confirm the excellent clinical efficacy of supplementing the diet with soy extracts, particularly genistein which is indicated to alleviate both the short-term symptoms of menopause and the long-term effects, although the latter finding requires further subsantiation.
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PMID:[A natural alternative to menopausal hormone replacement therapy. Phytoestrogens]. 1182 70

The management of oestrogen deficiency bone loss needs to include general measures to protect against osteoporosis, the identification and treatment of other reversible causes of bone loss, and the use of proven agents for the treatment of osteoporosis. The general measures include improved physical activity, adequate diet (paying particular attention to calcium and vitamin D), and avoidance of behaviours that promote bone loss, such as smoking and alcohol abuse. The diseases that should be identified, other than estrogen-deficiency, include primary hyperparathyroidism, thyrotoxicosis and celiac disease. The treatments that are proven to prevent fractures in women with estrogen deficiency, include hormone replacement therapy, raloxifene, nasal calcitonin, bisphosphonates, (alendronate and risedronate) and parathyroid hormone. The most appropriate therapy in the younger woman is HRT, although the trial-based evidence that HRT prevents fractures is not strong. There is a wide choice of preparations and the use of continuous combined preparations avoids regular menstrual periods, one of the limitations to the use of HRT. Raloxifene has less effect on bone mineral density than HRT, but a similar effect on vertebral fractures and does not result in menstrual bleeding or increased risk of breast cancer. There is recent evidence suggesting that the beneficial effects on lipids translate into reduced risk of cardiovascular disease. Bisphosphonates are the standard treatment for the older woman with osteoporosis. Alendronate has been found to reduce the risk of spine, hip, and wrist fractures and has approval for a once weekly regimen, an approach that appears to prevent GI side effects. Risedronate reduces the risk of spine and non-vertebral fractures within the first year of treatment and has been shown to reduce the risk of hip fracture. It has not been associated with an excess of GI side effects. Parathyroid hormone therapy results in increases in BMD that are even greater than estrogen and the bisphosphonates and to an even greater reduction in the risk of fractures, particularly non-vertebral fractures. It works by stimulation of bone formation rather than by inhibition of bone resorption. However, it has to be given by daily injection. Thus, we have a wide choice of therapies for the woman with osteoporosis due to ovarian failure.
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PMID:Management of osteoporosis due to ovarian failure. 1286 23

Tamoxifen is useful for adjuvant treatment of breast cancer and in some women for the prevention of breast cancer. The risk-benefit ratio in regard to the skeleton and perhaps other organ systems may very well be different for postmenopausal versus premenopausal women. In postmenopausal women, tamoxifen (20 mg/d) increased BMD in the spine and perhaps the hip; however, the effect on fracture risk is unclear. Therefore, for postmenopausal women with osteoporosis, consideration should be given to the addition of an agent that is shown to have efficacy against fractures (such as bisphosphonates), even while these women are on tamoxifen. For women at only modest or moderate risk, with bone density above the osteoporosis range (T score above -2.5) and no major fracture history, tamoxifen is probably adequate for 5 years of use. Potentially serious adverse effects include venous thromboembolism, uterine cancer, benign uterine disease, and cataracts. Raloxifene (60 mg/d) protects against vertebral fractures over 4 years in women with osteoporosis, produces small increases in bone mass of the spine, hip, and total body, and reduces bone turnover in postmenopausal women with or without osteoporosis. No significant effect has yet been demonstrated on nonvertebral fractures after 4 years of treatment. Raloxifene has the additional benefit of substantially reducing the risk of ER-positive invasive breast cancer and does not increase the risk of uterine disease. Raloxifene increases the risk of venous thromboembolic disease to the same degree as tamoxifen and estrogen. Therefore, SERMS and estrogens are generally contraindicated in women with a previous history of venous thromboembolism or those who are at significantly increased risk. Raloxifene is probably most useful in women who have osteoporosis (T score = -2.5) or who are at risk (T score less than -1.5 with clinical risk factors) in the middle menopausal period (age 55-65) or in the early menopausal period in women who have no significant hot flashes. At this stage in life, vertebral fractures are common, but hip fractures are not. Therefore, women who take raloxifene can expect a reduction in the likelihood of having a vertebral fracture, and possibly breast cancer. The lack of definitive efficacy against hip fracture is not a major deterrent to use of this agent in this age group because hip fracture risk is very low. Raloxifene might not be the treatment of choice for elderly women who are at particularly high risk of hip fracture.
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PMID:Selective estrogen-receptor modulators. 1291 92

Cancer treatment-induced bone loss is an emerging problem for patients with breast and prostate cancer, who are often treated with cancer therapies earlier in the disease process. Bone loss associated with cancer therapy can also progress rapidly and may cause significant morbidity in these patients. Many patients with metastatic prostate or breast cancer develop bone metastases and subsequent skeletal-related events. Studies suggest that bisphosphonates can maintain bone health when introduced early in the continuum of cancer care. They have shown efficacy in the prevention of bone loss and the more potent i.v. bisphosphonate, zoledronic acid, has prevented bone loss in addition to increasing BMD in prostate cancer patients with cancer treatment-induced bone loss. Intravenous zoledronic acid or pamidronate can be considered the standard of care for the treatment of osteolytic bone metastases in breast cancer. Clinical trials addressing the treatment of bone metastases related to prostate cancer have shown zoledronic acid to be the only bisphosphonate to have a significant positive effect on skeletal-related events.
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PMID:New generation of bisphosphonates: broad clinical utility in breast and prostate cancer. 1520 85

Previous studies have indicated a relationship between bone mineral density and the incidence of breast cancer in middle-aged and elderly women, with women with higher BMD being at significant increased risk. We investigated whether there was such a relationship in younger women who were perimenopausal or in their early postmenopausal years. As part of a population-screening program for osteoporosis, 5,119 women aged between 45 and 54 years were scanned between 1990-1994 at the Osteoporosis Research Unit. In 1997-2001, 3,884 returned for follow-up scans and questionnaires, and 3,144 returned a postal questionnaire in 2002. All cases of incident breast cancer were noted. One hundred sixty-six women indicated that they had suffered from breast cancer, of which 87 were incident cases (59 had prevalent breast cancer at baseline and 20 had benign or unconfirmed diagnosis and were excluded because of the use of agents that may interfere with BMD, e.g., tamoxifen). We compared therefore the incident breast cancer group (BC group; n=87) with a control group (C group; n=3,013). There were no significant differences using a t-test between the BC group and C group for baseline DXA of the spine or femoral neck. Further changes in BMD over a mean period of 6.9 years demonstrated no significant hazard ratio for the lumbar spine or femoral neck. No relationship was seen between the bone turnover markers pyridinoline/creatinine or deoxypyridinoline/creatinine assessed at their second study visit and incidence of breast cancer. In conclusion, in perimenopausal or early postmenopausal women there is no relationship between the incidence of breast cancer and BMD, change in BMD or bone turnover.
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PMID:Axial BMD, change in BMD and bone turnover do not predict breast cancer incidence in early postmenopausal women. 1578 81

Bone remodeling is a process by which bone renews itself focally in distinct areas on cancellous (ie, trabecular) bone and/or in the Haversian systems of cortical (or compact) bone. Normal bone turnover involves the ordered metabolism of bone-resorbing cells (osteoclasts) and bone-forming cells (osteoblasts). Estrogen exerts a multitude of actions on bone tissues and is integral to bone health, and estrogen deprivation leads to accelerated bone loss. Bone strength reflects the integration of bone density and bone quality. Methods to assess bone strength fall into 3 categories: radiologic (ie, bone mineral density [BMD]), biochemical (ie, markers of bone turnover), and histologic (ie, bone biopsies for histomorphometry). The beneficial effect of aromatase inhibitors (AIs) and inactivators on breast cancer depends on reducing levels of circulating estrogens in the peripheral blood. There appears to be variability in the effects of AIs on bone in experimental animals, and this variability may not be the same in humans. In general, bone loss is an expected side effect of the AIs. For postmenopausal women receiving adjuvant anastrozole or other AIs, a BMD measurement using dual-energy x-ray absorptiometry is recommended, to be repeated every 1-2 years. Regular physical exercise is advised together with added calcium 1500 mg and vitamin D 800 U daily. If the T-score reaches a level of >2.5, or if it is between -1.5 and -2.5 in the presence of a fragility fracture or vertebral compression fracture, or if height loss > 2 cm occurs or BMD decreases > 3% in 1 year at the lumbar spine or > 5% at the femoral neck, bisphosphonate therapy should be considered.
Clin Breast Cancer 2005 Feb
PMID:Evaluating bone mass and bone quality in patients with breast cancer. 1580 23


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