American Society of Clinical Oncology guideline on the role of bisphosphonates in breast cancer. American Society of Clinical Oncology Bisphosphonates Expert Panel.
(33/1716)
PURPOSE: To determine clinical practice guidelines for the use of bisphosphonates in the prevention and treatment of bone metastases in breast cancer and their role relative to other therapies for this condition. METHODS: An expert multidisciplinary panel reviewed pertinent information from the published literature and meeting abstracts through May 1999. Additional data collected as part of randomized trials and submitted to the United States Food and Drug Administration were also reviewed, and investigators were contacted for more recent information. Values for levels of evidence and grade of recommendation were assigned by expert reviewers and approved by the panel. Expert consensus was used if there were insufficient published data. The panel addressed which patients to treat and when in their course of disease, specific drug delivery issues, duration of therapy, management of bony metastases with other therapies, and the public policy implications. The guideline underwent external review by selected physicians, members of the American Society of Clinical Oncology (ASCO) Health Services Research Committee, and the ASCO Board of Directors. RESULTS: Bisphosphonates have not had an impact on the most reliable cancer end point: overall survival. The benefits have been reductions in skeletal complications, ie, pathologic fractures, surgery for fracture or impending fracture, radiation, spinal cord compression, and hypercalcemia. Intravenous (IV) pamidronate 90 mg delivered over 1 to 2 hours every 3 to 4 weeks is recommended in patients with metastatic breast cancer who have imaging evidence of lytic destruction of bone and who are concurrently receiving systemic therapy with hormonal therapy or chemotherapy. For women with only an abnormal bone scan but without bony destruction by imaging studies or localized pain, there is insufficient evidence to suggest starting bisphosphonates. Starting bisphosphonates in patients without evidence of bony metastasis, even in the presence of other extraskeletal metastases, is not recommended. Studies of bisphosphonates in the adjuvant setting have yielded inconsistent results. Starting bisphosphonates in patients at any stage of their nonosseous disease, outside of clinical trials, despite a high risk for future bone metastasis, is currently not recommended. Oral bisphosphonates are one of several options which can be used for preservation of bone density in premenopausal patients with treatment-induced menopause. The panel suggests that, once initiated, IV bisphosphonates be continued until evidence of substantial decline in a patient's general performance status. The panel stresses that clinical judgment must guide what is a substantial decline. There is no evidence addressing the consequences of stopping bisphosphonates after one or more adverse skeletal events. Symptoms in the spine, pelvis, or femur require careful evaluation for spinal cord compression and pathologic fracture before bisphosphonate use and if symptoms recur, persist, or worsen during therapy. The panel recommends that current standards of care for cancer pain, analgesics and local radiation therapy, not be displaced by bisphosphonates. IV pamidronate is recommended in women with pain caused by osteolytic metastasis to relieve pain when used concurrently with systemic chemotherapy and/or hormonal therapy, since it was associated with a modest pain control benefit in controlled trials. CONCLUSION: Bisphosphonates provide a meaningful supportive but not life-prolonging benefit to many patients with bone metastases from cancer. Further research is warranted to identify clinical predictors of when to start and stop therapy, to integrate their use with other treatments for bone metastases, to identify their role in the adjuvant setting in preventing bone metastases, and to better determine their cost-benefit consequences. (+info)
Managing menopause.
(34/1716)
Many women will spend one third of their lifetime after menopause. A growing number of options are available for the treatment of menopausal symptoms like vasomotor instability and vaginal atrophy, as well as the long-term health risks such as cardiovascular disease and osteoporosis that are associated with menopause. Currently, hormone replacement therapy (estrogen with or without progestin) is the primary treatment for the symptoms and long-term risks associated with menopause. However, recent evidence calls into question the protective effect of estrogen on cardiovascular disease risk. The association of risk for breast cancer with estrogen replacement therapy also has not been fully clarified. In addition, many women cannot or choose not to take hormones. For treatment of osteoporosis and heart disease, pharmacologic choices include antiresorptive agents such as bisphosphonates and calcitonin, and estrogens or selective estrogen receptor modulators such as raloxifene. In addition, complementary options that include vitamins, herbal treatments, exercise and other lifestyle adaptations are gaining increased interest. The growing number of choices and questions in this area emphasizes the need to individualize a treatment plan for each woman to meet her specific needs. (+info)
Polyphosphate in bone.
(35/1716)
Human bone-forming osteoblasts are an excellent model to investigate the multiple functions of inorganic polyphosphates (polyP) for the following reasons: 1) they contain relatively high amounts of polyP and polyP-dependent enzymes; 2) they allow the study of both general and specific functions of these polymers, and 3) medically relevant results can be expected from these studies. (+info)
Bisphosphonates in the adjuvant treatment of cancer: experimental evidence and first clinical results. International Bone and Cancer Study Group (IBCG).
(36/1716)
Several animal models, as well as a number of cell culture experiments, indicate a prophylactic effect of bisphosphonates in respect of subsequent bone metastasis. Moreover, in preliminary clinical trials involving patients with advanced breast cancer and local or remote metastases, biophosphonates produced a reduction in new skeletal metastases. This overview summarizes and discusses the results of the latest investigations. It opens with a section on the pathophysiology of bone metastasis, which is followed by a report on animal models and first studies of bisphosphonate treatment as a new approach in systemic adjuvant therapy. (+info)
Bisphosphonates induce apoptosis in human breast cancer cell lines.
(37/1716)
Breast cancer has a prodigious capacity to metastasize to bone. In women with advanced breast cancer and bone metastases, bisphosphonates reduce the incidence of hypercalcaemia and skeletal morbidity. Recent clinical findings suggest that some bisphosphonates reduce the tumour burden in bone with a consequent increase in survival, raising the possibility that bisphosphonates may have a direct effect on breast cancer cells. We have investigated the in vitro effects of bisphosphonates zoledronate, pamidronate, clodronate and EB 1053 on growth, viability and induction of apoptosis in three human breast cancer cell lines (MDA-MB-231, Hs 578T and MCF-7). Cell growth was monitored by crystal violet dye assay, and cell viability was quantitated by MTS dye reduction. Induction of apoptosis was determined by identification of morphological features of apoptosis using time-lapse videomicroscopy, identifying morphological changes in nucleis using Hoechst staining, quantitation of DNA fragmentation, level of expression of bcl-2 and bax proteins and identification of the proteolytic cleavage of Poly (ADP)-ribose polymerase (PARP). All four bisphosphonates significantly reduced cell viability in all three cell lines. Zoledronate was the most potent bisphosphonate with IC50 values of 15, 20 and 3 microM respectively in MDA-MB-231, MCF-7 and Hs 578T cells. Corresponding values for pamidronate were 40, 35 and 25 microM, whereas clodronate and EB 1053 were more than two orders of magnitude less potent. An increase in the proportion of cells having morphological features characteristic of apoptosis, characteristic apoptotic changes in the nucleus, time-dependent increase in the percentage of fragmented chromosomal DNA, down-regulation in bcl-2 protein and proteolytic cleavage of PARP, all indicate that bisphosphonates have direct anti-tumour effects on human breast cancer cells. (+info)
Short- and long-term effects of ibandronate treatment on bone turnover in Paget disease of bone.
(38/1716)
BACKGROUND: In Paget disease of bone (PD), serum total alkaline phosphatase (TAP) is a valid marker of disease activity. The aim of the present longitudinal study was to compare TAP with new and potentially more specific markers of bone turnover in bisphosphonate-treated patients with PD. METHODS: Twenty patients with active PD were studied before and after treatment with 2 mg of intravenous ibandronate over a period of 12 months. TAP (by colorimetry), serum bone-specific alkaline phosphatase (BAP; by enzyme immunoassay), serum osteocalcin (OC; by ELISA), serum bone sialoprotein (BSP; by RIA), and urinary total pyridinoline (PYD; by HPLC) and deoxypyridinoline (DPD; by HPLC) were measured as markers of bone turnover. RESULTS: Before treatment, TAP, BAP, and BSP were increased in all 20 patients, whereas OC was increased in 10, PYD in 13, and DPD in 15 patients. Three months post treatment, nine patients showed normalized TAP values, and a >/=25% re-increase (i.e. , relapse) was observed in all patients after 12 months. A normalization of BAP was achieved in six patients only. No significant changes were found for OC. BSP was decreased significantly at 24 h, and DPD at 48 h post treatment. A normalization of BSP was found in 8, of PYD in 18, and of DPD in 16 cases. Both PYD and DPD increased significantly from 9 months post treatment onward. CONCLUSIONS: Most markers of bone turnover show similar long-term changes after treatment of active PD with ibandronate. With regard to cost-effectiveness and assay performance, TAP remains the marker of choice in therapeutic monitoring of PD. However, more specific markers may improve the biochemical assessment of PD in certain situations. (+info)
Bisphosphonates: safety and efficacy in the treatment and prevention of osteoporosis.
(39/1716)
Osteoporosis affects more than 28 million Americans. With the advent of accessible and affordable diagnostic studies, awareness and recognition of this disease by patients and clinicians are growing. Osteoporotic fractures of the spine and hip are costly and associated with significant morbidity and mortality. Over the past decade, a surge of new antiosteoporotic drugs have been labeled or are awaiting labeling by the U.S. Food and Drug Administration. One class of agents used to treat osteoporosis is the bisphosphonates, which inhibit bone resorption, cause an increase in bone mineral density and reduce the risk of future fractures caused by aging, estrogen deficiency and corticosteroid use. Overall, bisphosphonates have been shown to have a strong safety and tolerability profile. (+info)
Bisphosphonates inhibit breast and prostate carcinoma cell invasion, an early event in the formation of bone metastases.
(40/1716)
The molecular mechanisms by which tumor cells metastasize to bone are likely to involve invasion, cell adhesion to bone, and the release of soluble mediators from tumor cells that stimulate osteoclast-mediated bone resorption. Bisphosphonates (BPs) are powerful inhibitors of the osteoclast activity and are, therefore, used in the treatment of patients with osteolytic metastases. However, an added beneficial effect of BPs may be direct antitumor activity. We previously reported that BPs inhibit breast and prostate carcinoma cell adhesion to bone (Boissier et al., Cancer Res., 57: 3890-3894, 1997). Here, we provided evidence that BP pretreatment of breast and prostate carcinoma cells inhibited tumor cell invasion in a dose-dependent manner. The order of potency for four BPs in inhibiting tumor cell invasion was: zoledronate > ibandronate > NE-10244 (active pyridinium analogue of risedronate) > clodronate. In addition, NE-58051 (the inactive pyridylpropylidene analogue of risedronate) had no inhibitory effect, whereas NE-10790 (a phosphonocarboxylate analogue of risedronate in which one of the phosphonate groups is substituted by a carboxyl group) inhibited tumor cell invasion to an extent similar to that observed with NE-10244, indicating that the inhibitory activity of BPs on tumor cells involved the R2 chain of the molecule. BPs did not induce apoptosis in tumor cells, nor did they inhibit tumor cell migration at concentrations that did inhibit tumor cell invasion. However, although BPs did not interfere with the production of matrix metalloproteinases (MMPs) by tumor cells, they inhibited their proteolytic activity. The inhibitory effect of BPs on MMP activity was completely reversed in the presence of an excess of zinc. In addition, NE-10790 did not inhibit MMP activity, suggesting that phosphonate groups of BPs are responsible for the chelation of zinc and the subsequent inhibition of MMP activity. In conclusion, our results provide evidence for a direct cellular effect of BPs in preventing tumor cell invasion and an inhibitory effect of BPs on the proteolytic activity of MMPs through zinc chelation. These results suggest, therefore, that BPs may be useful agents for the prophylactic treatment of patients with cancers that are known to preferentially metastasize to bone. (+info)