Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0006142 (breast cancer)
 160,383 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Clodronate (clodronic acid, dichloromethylene bisphosphonate) is a bisphosphonate which has demonstrated efficacy in patients with a variety of diseases of enhanced bone resorption including Paget's disease, hypercalcaemia of malignancy and osteolytic bone metastases. In addition, early reports demonstrating potential efficacy of clodronate in the treatment of osteoporosis suggest a possible role in this debilitating disease. Short term intravenous administration (usually 300 mg/day for 5 days) or longer courses of oral clodronate (usually 1600 mg/day for 6 months) effectively reduced bone pain and/or improved mobility in most patients with Paget's disease, and these effects persisted for up to 12 months after discontinuing clodronate. When administered intravenously (300 mg/day for up to 12 days) to patients with malignant hypercalcaemia, serum calcium levels declined significantly within 2 days of starting treatment and approximately 70 to 95% of patients became normocalcaemic. While there is less experience with oral administration, clodronate (800 to 3200 mg/day) achieved normocalcaemia in the majority of patients, usually within 1 week, and serum calcium levels remained significantly reduced from baseline for up to 6 months with continued treatment. Clodronate is clearly superior to placebo and, based on a retrospective analysis, appears to produce greater and more sustained reductions in serum calcium levels than calcitonin in patients with malignant hypercalcaemia. The few available prospective comparative trials showed that clodronate is at least as effective as etidronate, but comparisons with alendronate and pamidronate produced results of questionable clinical relevance because of low bisphosphonate dosages used in these trials. Nevertheless, single intravenous doses of clodronate 600 mg or alendronate 7.5 mg (both agents repeated on day 3 if necessary) were comparable in efficacy, whereas a single intravenous dose of pamidronate 30 mg was more effective than a single intravenous dose of clodronate 600 mg. Normocalcaemic patients with osteolytic bone metastases due to advanced breast cancer experienced significant reductions in the number of episodes of hypercalcaemia and terminal hypercalcaemia, incidence of vertebral fractures and overall rate of morbid events, including the need for radiotherapy to treat bone-related pain, following treatment with clodronate 1600 mg/day for 3 years in a large placebo-controlled study. A similar large placebo-controlled trial in patients with multiple myeloma demonstrated that clodronate 2400 mg/day orally for 2 years significantly reduced progression of osteolytic bone lesions. Follow-up data from clinical trials revealed that the effects on development of fractures and hypercalcaemia persisted for at least 12 months after the drug was discontinued.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Clodronate. A review of its pharmacological properties and therapeutic efficacy in resorptive bone disease. 752 33

The symptomatic postmenopausal woman with breast cancer presents the clinician with a difficult task with respect to hormone replacement therapy (HRT). All of the published meta-analyses have been consistent in showing that there is a slightly increased risk of developing breast cancer in those patients using postmenopausal estrogens for greater than 10 years. However, there have been no published placebo-controlled clinical trials on the effects of HRT in women with a history of breast cancer. Quality of life must be balanced against the theoretical risk of tumor promotion. Assessment of osteoporotic and cardiac risk factors (i.e., smoking, hypertension, family history, hyperlipidemia) should influence the decision. Valid alternatives to estrogen replacement include low-dose progesterones such as Bellergal or vitamin E for hot flashes, and biphosphonates, calcium, anabolic steroids, and calcitonin for osteoporosis.
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PMID:The management of menopausal symptoms in women with breast cancer. 761 Jun 43

Current medical practice recommends the use of alternatives to estrogen-replacement therapy for the treatment of menopausal sequelae in younger women with breast cancer, although this clinical recommendation is undergoing reappraisal. Until prospective randomized studies addressing hormone use in this population are available, estrogen use in breast cancer patients will remain controversial. Because estrogen-replacement therapy is not the standard of practice and there is limited information available on nonestrogen therapies, women with breast cancer who are menopausal may not be prescribed or counseled about nonestrogen options. The efficacy, safety, and extent of use of most nonestrogen treatment modalities (other hormonal preparations, nonhormonal drugs, homeopathic preparations, and non-drug treatments) are not well documented and, unlike estrogen, many are selective in their benefit and do not share estrogen's universal impact. The use of several nonestrogen approaches for the prevention and treatment of osteoporosis has been promising. Traditional recommendations to maintain skeletal integrity, such as weight-bearing exercise; a diet rich in calcium and limited in caffeine, alcohol, and protein; avoidance of smoking; and measures to minimize trauma have been expanded to include the use or investigation of drugs (either alone or in combination). These drugs include progestins, vitamin D metabolites, injectable and intranasal synthetic salmon calcitonin, bisphosphonates, sodium fluoride, parathyroid hormone, growth factors, tamoxifen, etc. Strict control of the known risk factors, such as smoking, dyslipidemia, and hypertension as well as exercise, weight control, and the use of tamoxifen, are employed for the prevention and treatment of cardiovascular complications.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Nonhormonal alternatives for the management of early menopause in younger women with breast cancer. 799 60

After mastectomy and radiation for breast cancer, two patients were found to have persistent elevated CEA in their serum. This finding was erroneously attributed to occult metastases for the first patient and to local recurrence for the second. Overlooked medullary thyroid carcinoma (MTC) was the causal disease in both patients. A review of the literature stresses the frequency of CEA elevation in serum of MTC patients. A thorough search for any possible cause of elevated levels of CEA is advocated, particularly by thyroid sonogram with a needle aspiration biopsy when a nodule is discovered and by calcitonin assay in the serum.
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PMID:Elevated CEA in breast cancer patients with overlooked medullary thyroid carcinoma. 810 Feb 1

The menopause is defined as cessation of menstruation, ending the fertile period. The hormonal changes are a decrease in progesterone level, followed by a marked decrease in estrogen production. Symptoms associated with these hormonal changes may advocate for hormonal replacement therapy. This review is based on the English-language literature on the effect of estrogen therapy and estrogen plus progestin therapy on postmenopausal women. The advantages of hormone replacement therapy are regulation of dysfunctional uterine bleeding, relief of hot flushes, and prevention of atrophic changes in the urogenital tract. Women at risk of osteoporosis will benefit from hormone replacement therapy. The treatment should start as soon after menopause as possible and it is possible that it should be maintained for life. The treatment may be supplemented with extra calcium intake, vitamin D, and maybe calcitonin. Physical activity should be promoted, and cigarette smoking reduced if possible. Women at risk of cardiovascular disease will also benefit from hormone replacement therapy. There is overwhelming evidence that hormone therapy will protect against both coronary heart disease and stroke, and there is no increased risk of venous thrombosis or hypertension. A disadvantage of hormone replacement therapy is an increased risk of forming gall-bladder stones and undergoing cholecystectomy. Unopposed estrogen therapy gives a higher incidence of endometrial cancer in women with an intact uterus, but the contribution of progestins for about 10 days every month excludes this risk. Breast cancer in relation to estrogen-progestogen therapy has been given much concern, and the problem is still not fully solved. If there is a risk, it is small, and only after prolonged use of estrogen (15-20 years). The decision whether or not to use hormone replacement therapy should, of course, be taken by the individual woman in question, but her decision should be based on the available scientific information. It is the opinion of the authors that the advantages of hormone replacement therapy far exceed the disadvantages. We suggest that every woman showing any signs of hormone deprivation should be treated with hormone replacement therapy. This includes women with subjective or objective vaso-motor symptoms, genito-urinary symptoms, women at risk of osteoporosis (fast bone losers), and women at risk of cardiovascular diseases.
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PMID:Postmenopausal hormone replacement therapy--clinical implications. 819 55

The use of calcitonin (CT) is established as a treatment of Paget's disease of bone and postmenopausal osteoporosis (PMO). Salmon calcitonin (sCT), which differs in 14 of the 32 amino acids from human calcitonin, has found a wider distribution world wide, although antibody formation against sCT has been reported in more than 70% of the patients on continuous sCT treatment. The clinical significance of these antibodies has been discussed controversially, because the occurrence of antibodies is not always associated with the development of secondary resistance. Using an in vitro bioassay, based on the CT-mediated increase of the cyclic AMP (cAMP) production of the human breast cancer cell line T 47 D we could identify a neutralizing activity against sCT in the serum of a subset of patients with formation of antibodies against sCT which was related to the development of secondary resistance. Antibody formation against human calcitonin (hCT) has been reported only once before. Binding and neutralizing antibodies were now observed in 1 of 33 patients with PMO treated with hCT. Due to a low neutralizing activity, clinical sequelae were not to be expected in this patient. The formation of neutralizing antibodies against calcitonin is common after treatment with salmon but a rare phenomenon after treatment with human calcitonin. We recommend monitoring of patients with postmenopausal osteoporosis and Paget's disease of bone on long term treatment with sCT or hCT for neutralizing antibody formation in order to evaluate the therapeutic effect of treatment.
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PMID:Neutralizing antibodies against calcitonin. 822 3

Estrogen deficiency is the main cause of postmenopausal osteoporosis. Replacement estrogen therapy protects the bone by reducing bone resorption and activating osteoblasts, as well as by promoting absorption of calcium and production of calcitonin. These preventive effects are especially marked in cancellous bone, provided estrogen therapy is initiated as soon as menstruation stops. Effects are dose-dependent and efficacy of the treatment is noticeable mainly during the period of administration. The rare contra-indications to estrogen therapy include hormone-dependent cancers, cholestatic jaundice, and large uterine myomas (for which surgical treatment is recommended). Metabolic disorders, arterial hypertension, and thyroid function disorders are less common with the new natural estrogens (estradiol) given orally or percutaneously to avoid hepatic passage of the drug. As for treatment induced cancers, sequential administration of a progestagen protects the endometrium and the relative risk seems negligible for breast cancer. Although concomitant use of a progestagen is mandatory, either natural progesterone or norpregnanes should be given to avoid adverse metabolic effects. Emphasis has recently been put on the role of concomitant progestagen therapy which may promote the formation of bone, probably by competing for glucocorticoid receptors in bone. There is still a need for prospective epidemiological studies, although evaluation methods and the long follow-ups needed raise significant problems.
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PMID:[Substitutive hormone therapy in postmenopausal osteoporosis. Are there any contraindications?]. 823 58

We studied the effects of long-term treatment with clodronate, calcitonin or placebo on bone in 36 normocalcaemic women with osteolytic metastases due to breast cancer. Clodronate (1.6 g daily given to 12 patients) induced a significant decrease in osteoclast surface and osteoclast number, and a significant fall in serum calcium and urinary excretion of calcium and hydroxyproline, an effect not noted after treatment with calcitonin (100 U in 12 patients) or in 12 placebo-treated patients. Treatment with clodronate did not abnormally suppress bone turnover nor impair mineralisation, as measured by bone formation and mineral apposition rates.
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PMID:Comparative effects of clodronate and calcitonin on bone in metastatic breast cancer: a histomorphometric study. 839 93

The variability of different primary tumors in the susceptibility to metastatic bone disease is poorly understood. Factors that determine the viability of metastatic cells are also poorly understood, but may depend in part upon gene expression of PTHrP and the vitamin D receptor. In contrast, much more is known of the manner in which metastatic disease affects bone remodeling to induce osteolytic bone disease. Mechanisms include a generalized increase in activation frequency at sites close to metastatic tissue, an imbalance between the amount of bone formed and that resorbed within resorption cavities, and uncoupling of bone formation from bone resorption. The greatest morbidity from metastatic bone disease arises from osteolytic disease and gives rise to hypercalcemia, bone pain, and fractures. Because osteolysis is primarily mediated by the activation of osteoclasts, there has been a great deal of interest in the use of agents which primarily affect bone metabolism to alter the natural history of metastatic bone disease. Nonsteroidal antiinflammatory agents and cytotoxic agents are capable of inducing responses in bone, but are limited by their toxicity when effective doses are utilized. The use of calcitonin in the long-term suppression of osteolysis has also been disappointing. The bisphosphonates are, however, capable of inducing sustained decreases in osteoclast activity and numbers in patients with osteolytic bone disease. There are now several studies which have examined the effects of the bisphosphonates on skeletal morbidity in breast cancer. Both clodronate and pamidronate decrease the incidence of hypercalcemia, bone pain, and pathological fractures, but do not significantly alter mortality.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Bone and cancer: pathophysiology and treatment of metastases. 857 90

In this study, the authors have analyzed the possible effects of one-year adjuvant treatment with tamoxifen on bone mineral density in postmenopausal breast cancer women. Bone mineral content was studied by photon absorptiometry (I-125), whereas bone balance was analyzed indirectly by serum PTH, osteocalcin, calcitonin, calcium and alkaline phosphatase levels. Bone mineral content and serum bone-related substances were measured before starting treatment and after one year. Results were analyzed using Student's t test for paired data. No difference was found between the two measurements for bone mineral content, PTH, calcitonin, calcium and alkaline phosphatase levels. Measurements at entry and after one year of treatment showed a statistically significant difference (P<0.001) only for osteocalcin. In accordance with other authors, we can conclude that treatment with tamoxifen does not cause an increase in menopausal bone resorption. The finding that osteocalcin levels decreased after one year of therapy with tamoxifen is interesting, but further studies are necessary to clarify the role of such levels in predicting a turnover of bone balance towards osteoblastic activity.
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PMID:Effects of one-year adjuvant treatment with tamoxifen on bone mineral density in postmenopausal breast cancer women. 862 9


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