Oral ibandronate is as active as intravenous zoledronic acid for reducing bone turnover markers in women with breast cancer and bone metastases

The Preventive Effect of Preoperative and Postoperative Selenium on the Medication-Related Osteonecrosis of the Jaw: An Animal Study in Rats

BACKGROUND

Medication-related osteonecrosis of the jaw (MRONJ) is a condition that can occur primarily in patients undergoing or have previously undergone therapy with bisphosphonates, particularly in the presence of risk factors, such as tooth extraction (TE).

PURPOSE

This study aimed to evaluate the effect of selenium (SEL) administration on the prevention of osteonecrosis of the jaw in an MRONJ animal model.

STUDY DESIGN, SETTING, AND SAMPLE

This study was a longitudinal in vivo animal study using a TE model in a sample of 48 Wistar rats.

PREDICTOR VARIABLE

The predictor variables were SEL exposure, timing of SEL exposure, and zoledronic acid (ZOL) exposure. The animals were randomly assigned to 4 treatment groups (n = 12 per group): 1) saline (negative control), 2) ZOL (positive control), 3) SELpreop + ZOL, and 4) ZOL + SELpostop. The animals were administered saline (negative control) or ZOL (0.06 mg/kg, intraperitoneally) once a week for 5 weeks. All rats underwent TE at the end of the fifth week. SEL (0.3 mg/kg, intraperitoneally) was administered once daily for 15 days to the SELpreop + ZOL group before TE and to the ZOL + SELpostop group after TE. All animals were sacrificed at the end of the ninth week.

MAIN OUTCOME VARIABLES

The primary outcome variables were new bone area, necrotic bone area, fibrosis, new connective tissue formation, and inflammatory cell infiltration in the histopathological analysis, as well as angiogenesis and percentage of osteoblasts in the immunohistochemical analysis.

COVARIATES

There was none.

ANALYSES

Statistical analysis was conducted using the Kruskal-Wallis test, followed by post hoc Bonferroni-corrected Mann-Whitney U tests, with a significance level of P ≤ .05.

RESULTS

The new bone area was higher in the ZOL + SELpostop group (3.00 score) than in the saline group (0.58 ± 1.08 score, P < .001) and the ZOL group (0.82 ± 1.40 score, P = .001), while the necrotic bone area was lower in the ZOL + SELpostop group (0.08 ± 0.29 score) than in the ZOL group (2.82 ± 0.40 score, P < .001) and the SELpreop + ZOL group (1.67 ± 0.89 score, P = .007). The percentage of osteoblasts was higher in the ZOL + SELpostop group (18.73%) than in the saline group (8.63%, P < .001) and the ZOL group (0.07%, P < .001), and it was also higher in the SELpreop + ZOL group (18.49%) than in the ZOL group (0.07%, P < .001).

CONCLUSION AND RELEVANCE

In conclusion SEL prevents MRONJ, with postoperative SEL demonstrating greater prevention effects. Given these findings, we hypothesize that SEL exposure may decrease the risk of MRONJ.

Efficacy and Safety of Oral Ibandronate versus Intravenous Zoledronic Acid on Bone Metabolism and Bone Mineral Density in Postmenopausal Japanese Women with Osteoporosis

There are no published clinical reports comparing ibandronate (IBN) treatment and zoledronic acid (ZOL) treatment in Japanese postmenopausal osteoporotic patients. This investigation therefore compared the efficacy and safety of the drugs on improving bone metabolism and bone mineral density (BMD) in Japanese postmenopausal women with primary osteoporosis. Eighty-two treatment-naïve primary osteoporotic female patients were randomly divided into IBN-treated or ZOL-treated groups. Bone turnover markers and BMD were examined immediately prior to treatment (baseline) and at 6, 12, 18, 24, and 30 months of therapy. Compared with baseline levels, the values of type 1 procollagen N-terminal propeptide, bone-specific alkaline phosphatase (BAP), urinary type-I collagen amino-terminal telopeptide (NTX), and tartrate-resistant acid phosphatase 5b were all significantly decreased at every time point in both groups apart from BAP at 30 months in the ZOL group, urinary NTX at 12 months in the ZOL group and at 24 and 30 months in both groups. Lumbar BMD values were significantly increased at 6, 12, 18, and 24 months in the IBN group and at 6 and 12 months in the ZOL group compared with pre-treatment levels. Hip BMD values were also significantly increased at 6, 12, 18, and 24 months in the IBN group and at 6, 12, and 18 months in the ZOL group compared with baseline values. The percentage changes of hip BMD at 18 and 24 months in the ZOL group were significantly higher than those in the IBN group (both p < 0.05). No remarkable adverse events were noted in either group. In conclusion, both IBN and ZOL significantly and safely improved bone turnover markers and BMD during 30 months of treatment in Japanese osteoporosis patients. The ZOL group tended to exhibit greater gains in BMD as compared with the IBN group, which merits further investigation.

Management of bone health in solid tumours: From bisphosphonates to a monoclonal antibody

Patients with solid tumours are at risk of impaired bone health from metastases and cancer therapy-induced bone loss (CTIBL). We review medical management of bone health in patients with solid tumours over the past 30 years, from first-generation bisphosphonates to the receptor activator of nuclear factor κB ligand (RANKL)-targeted monoclonal antibody, denosumab. In the 1980s, first-generation bisphosphonates were shown to reduce the incidence of skeletal-related events (SREs) in patients with breast cancer. Subsequently, more potent second- and third-generation bisphosphonates were developed, particularly zoledronic acid (ZA). Head-to-head studies showed that ZA was significantly more effective than pamidronate for reducing SREs in patients with breast and castrate-resistant prostate cancer (CRPC), becoming the standard of care for more than a decade. The RANKL inhibitor denosumab was licensed in 2010, and head-to-head studies and integrated analyses confirmed its superiority to ZA for preventing SREs, particularly in breast cancer and CRPC. Bisphosphonates and denosumab have also been investigated for prevention of CTIBL in patients receiving hormonal therapy for breast and prostate cancer, and denosumab is licensed in this indication. Despite advances in management of bone health, several issues remain, notably the optimal time to initiate therapy, duration of therapy, and dosing frequency, and how to avoid toxicity, particularly with long-term treatment. In summary, introduction of ZA and denosumab has protected patients with bone metastasis from serious bone complications and improved their quality of life. Ongoing research will hopefully guide the optimal use of these agents to help maintain bone health in patients with solid tumours.

Evidence on the analgesic role of bisphosphonates and denosumab in the treatment of pain due to bone metastases: A systematic review within the European Association for Palliative Care guidelines project

BACKGROUND

Bisphosphonates and denosumab are well-established therapies to reduce the frequency and severity of skeletal-related events in patients with bone metastasis. However, the analgesic effect of these medications on bone pain is uncertain.

AIM

To identify, critically appraise and synthesize existing evidence to answer the following questions: 'In adult patients with metastatic bone pain, what is the evidence that bisphosphonates and denosumab are effective and safe in controlling pain?' and 'What is the most appropriate schedule of bisphosphonate/denosumab administration to control bone pain?'. This review also updates the 2002 Cochrane review 'Bisphosphonates for the relief of pain secondary to bone metastases'.

DESIGN

Standard systematic review and narrative synthesis.

DATA SOURCES

MEDLINE, EMBASE and Cochrane CENTRAL databases were searched for relevant articles published through 31 January 2014. A manual search was also performed. Study inclusion criteria were: a) conducted in adult patients; b) randomized controlled trial or meta-analisys; c) reported efficacy of bisphosphonates or denosumab on pain and/or decribed side effects versus placebo or other bisphosphonate; and d) English language.

RESULTS

The database search yielded 1585 studies, of which 43 (enrolling 8595 and 7590 patients, respectively, in bisphosphonate and denosumab trials) met the inclusion criteria. Twenty-two (79%) of the 28 placebo-controlled trials found no analgesic benefit for bisphosphonates. None of the denosumab studies assessed direct pain relief.

CONCLUSION

Evidence to support an analgesic role for bisphosphonates and denosumab is weak. Bisphosphonates and denosumab appear to be beneficial in preventing pain by delaying the onset of bone pain rather than by producing an analgesic effect per se.

Skeletal metastases from breast cancer: pathogenesis of bone tropism and treatment strategy

Breast cancer (BC) is the most common female cancer worldwide with approximately 10 % of new cases metastatic at diagnosis and 20-50 % of patients with early BC who will eventually develop metastatic disease. Bone is the most frequent site of colonisation and the development of skeletal metastases depends on a complex multistep process, from dissemination and survival of malignant cells into circulation to the actual homing and metastases formation inside bone. Disseminated tumor cells (DTCs) can be detected in bone marrow in approximately 30 % of BC patients, likely reflecting the presence of minimal residual disease that would eventually account for subsequent metastatic disease. Patients with bone marrow DTCs have poorer overall survival compared with patients without them. Although bone-only metastatic disease seems to have a rather indolent behavior compared to visceral disease, bone metastases can cause severe and debilitating effects, including pain, spinal cord compression, hypercalcemia and pathologic fractures. Delivering an appropriate treatment is therefore paramount and ideally it should require interdisciplinary care. Multiple options are currently available, from bisphosphonates to new drugs targeting RANK ligand and radiotherapy. In this review we describe the mechanisms underlying bone colonization and provide an update on existing systemic and locoregional treatments for bone metastases.

Bone-targeted agents in the treatment of lung cancer

Over a third of patients with lung cancer will develop bone metastases during the course of their disease, resulting in symptoms of pain and immobility, and skeletal-related events (SREs) such as fracture, hypercalcaemia, surgery or radiotherapy to bones, and malignant spinal cord compression. These reduce quality of life and increase mortality. Preclinical research has identified the interactions between tumour cells and bone that are key to tumour cell survival and associated osteolysis. These data have led to the development of drugs to prevent osteoclast-mediated bone breakdown, such as zoledronic acid and denosumab, which are now licensed for use in patients with bone metastases from solid tumours. Both zoledronic acid and denosumab reduce the risk of SREs and increase time to first SRE, with minimal side effects. In addition, denosumab improved survival in patients with lung cancer compared with zoledronic acid. Ongoing trials are testing whether these drugs can prevent the development of bone metastases from lung cancer. New bone-targeted agents showing promise in breast and prostate cancer include radium-223, cabozantinib and Src inhibitors. These agents require further evaluation in patients with lung cancer.

Ibandronate to treat skeletal-related events and bone pain in metastatic bone disease or multiple myeloma: a meta-analysis of randomised clinical trials

OBJECTIVE

Randomised controlled trials (RCTs) have given contradictory results about the efficacy and safety of ibandronate in treating metastatic bone disease (MBD) or multiple myeloma. This review meta-analysed the literature to gain a more comprehensive picture.

DESIGN

Systematic review and meta-analysis of ibandronate compared with placebo or zoledronate.

DATA SOURCES

PubMed, EMBASE and the Cochrane Library databases were systematically searched to identify RCTs published up to March 2015 evaluating ibandronate to treat MBD or multiple myeloma.

REVIEW METHOD

10 RCTs involving 3474 patients were included. Six RCTs were placebo-controlled and four compared ibandronate with zoledronate. The studies included in this review were mainly from European countries.

RESULTS

Intravenous ibandronate (6 mg) or oral drug (50 mg) decreased the risk of skeletal-related events compared to placebo (risk ratio (RR) 0.80, 95% CI 0.71 to 0.90, p=0.002). It also reduced the bone pain score below baseline significantly more than did placebo at 96 weeks (weighted mean difference -0.41, 95% CI -0.56 to -0.27, p<0.001). The incidence of diarrhoea, nausea and adverse renal events was similar between the ibandronate and placebo groups, but ibandronate was associated with greater risk of abdominal pain. Ibandronate was associated with similar risk of skeletal-related events as another bisphosphonate drug, zoledronate (RR 1.02, 95% CI 0.82 to 1.26, p=0.87). The incidence of nausea, jaw osteonecrosis and fatigue was similar for the two drugs, but the incidence of adverse renal events was significantly lower in the ibandronate group.

CONCLUSIONS

Ibandronate significantly reduces the incidence of skeletal-related events and bone pain in patients with MBD or multiple myeloma relative to placebo. It is associated with a similar incidence of skeletal-related events as zoledronate.

Gorham-Stout disease of the proximal fibula treated with radiotherapy and zoledronic acid

Gorham-Stout disease is a rare disease characterized by anarchic lymphovascular proliferation causing resorption of bone sometimes leading to disastrous complications. Bone tissue is progressively replaced by angiomatic and lymphangiomatic tissue and finally by fibrous tissue. This disease is known to be ubiquitous and of complex etiology. We present a case of Gorham-Stout disease of the proximal fibula invading the proximal tibia and soft tissues of the popliteal space that was successfully treated with radiotherapy and zoledronic acid.

Loading dose ibandronate versus standard oral ibandronate in patients with bone metastases from breast cancer

INTRODUCTION

In this phase II trial, the efficacy and safety of loading-dose I.V. ibandronate in patients with breast cancer with bone metastases were evaluated.

PATIENTS AND METHODS

Thirty-four patients were randomized to receive a loading dose of 12 mg I.V. ibandronate on day 1 then oral ibandronate 50 mg daily (arm A), or standard oral therapy of 50 mg ibandronate daily from day 1 (arm B). The primary end point was percentage change in serum C-terminal crosslinking telopeptide of type I collagen (S-CTX) from baseline by day 5 of study. Secondary/exploratory end points included percentage change in other bone turnover markers (N-terminal cross-linking telopeptides of type I collagen [NTX], procollagen type I N propeptide, bone alkaline phosphatase) and change in average bone pain score.

RESULTS

There was a significantly greater reduction in S-CTX at day 5 in arm A compared with arm B (median difference, 15.82%; P = .005). There was also a significantly greater reduction in urine NTX/creatinine at day 5 (P = .009) and at the end of weeks 1 to 8 (averaged; P = .006). Average bone pain score was lower in arm A at the end of 8 weeks (P = .012). There were no additional adverse events after administration of 12 mg I.V. loading dose of ibandronate.

CONCLUSION

A 12-mg dose of I.V. ibandronate rapidly reduced markers of bone turnover and can be administered without additional toxicity.

Zoledronic acid in the treatment of metastatic breast cancer

Bone is the most common location of metastatic disease. Approximately 80% of all bone metastases are observed in patients with breast or prostate tumours and are responsible for more than 300 000 deaths every year. Treatment of malignant bone disease with bisphosphonates has been shown to reduce bone events and delay their onset, and several reviews and meta-analyses have confirmed the benefit of these drugs in controlling bone metastases. Zoledronic acid is a bisphosphonate that has been shown to delay or prevent the development of skeletal-related events in patients with bone metastases. Furthermore, compared with other bisphosphonates, zoledronic acid has also shown better pain control and various studies also suggest an improvement in quality of life, although with no impact on overall survival. The duration and optimal regimen for long-term zoledronic acid therapy have not yet been defined, but some studies suggest that continuing zoledronic acid therapy for more than 2 years could also extend its beneficial effect.

Adverse events across generations of bone-modifying agents in patients with solid tumor cancers reported in Phase III randomized trials

AIMS

The objective of this study is to compare adverse events experienced among different bone-modifying agents.

METHODS

A literature search was conducted to identify Phase III bisphosphonate and bone-modifying agent trials reporting adverse effects. Thirty-seven adverse events of interest were identified for six different treatment options. Weighted linear regression modeling was performed on the adverse event proportions with treatment groups, normalized through applying natural log transformations.

RESULTS

There were significant differences in adverse events of vomiting (p = 0.045) and osteonecrosis of the jaw (p = 0.017), and combined item events of nausea/vomiting (p = 0.048), hematological and lymphatic system toxicities (p = 0.020), and any respiratory system problem (p = 0.023) between bone-modifying agent and placebo trials. The significant toxicities were observed even after adjusting for the two confounding factors of age and primary cancer site.

CONCLUSION

While adverse effects are consistently experienced more frequently in patients receiving bone-modifying agents when compared with placebos, we find that the majority of individual side effects are not significantly more frequent in patients receiving bone-modifying agents compared with placebo.

Comparison of the efficacy and safety of denosumab versus bisphosphonates in breast cancer and bone metastases treatment: A meta-analysis of randomized controlled trials

Breast cancer is the most common type of cancer in females worldwide. Patients with breast cancer and bone metastases may experience increased osteoclast activity, resulting in local bone destruction and skeletal complications, including pain, hypercalcemia and skeletal-related events. Intravenous bisphosphonates (BPs) are the standard treatment administered to patients with breast cancer and bone metastases to prevent skeletal-related events. However, in certain patients, BPs may cause renal toxicity, acute-phase reactions and osteonecrosis of the jaw. More effective, safer and more tolerable therapies, which prevent bone destruction and skeletal complications, are required in order to improve patient quality of life. Denosumab is a fully human monoclonal antibody that binds to and neutralizes receptor activator of nuclear factor-κB ligand, which is a key mediator in the pathogenesis of a broad range of skeletal diseases, thereby inhibiting osteoclast function and bone resorption. Therefore, we conducted a meta-analysis to compare both the safety and efficacy of denosumab and BPs in the treatment of breast cancer and bone metastases. Five databases, two clinical trial registry platforms and reference lists of relevant papers were analyzed. The meta-analysis concluded that denosumab was more effective at preventing pain and skeletal-related events than BPs, in patients with breast cancer and bone metastases. Patients receiving denosumab demonstrated a higher level of clinical improvement in terms of health-related quality of life than patients receiving BPs. Compared with BPs, denosumab reduced the incidence of certain indicators of adverse events, including pyrexia, bone pain, edema and renal failure.

Procollagen assays in cancer

The synthesis rates of fibrillar collagens can be assessed in blood by measuring propeptides set free from corresponding procollagens before fiber formation. Type I collagen is the major component of the organic matrix of bone, but it is also found in other connective tissues. The serum concentration of the amino-terminal propeptide of type I procollagen, PINP, functions as a measure of type I collagen synthesis during normal bone turnover, but it is also released from bone metastases that involve an osteoblastic component. Type III collagen is a major constituent of soft tissues and the corresponding amino-terminal propeptide, PIIINP, reflects collagen synthesis. Circulating PIIINP tends to be affected by malignomas that grow in the peritoneal cavity or affect bone marrow. Many studies on procollagen markers in cancer have been cross-sectional or demonstrated treatment effects in patient groups. Markers that originate from bone turnover have wide reference intervals, but low biologic variability in individuals. Thus, they appear better suited for monitoring versus diagnostic purposes. There is still definite need for research on the use of procollagen markers in the followup of individual patients undergoing cancer treatment or being monitored after such treatment.

Bone Health in Patients with Breast Cancer: Recommendations from an Evidence-Based Canadian Guideline

Bone loss is common in patients with breast cancer. Bone modifying agents (BMAs), such as bisphosphonates and denosumab, have been shown to reverse or stabilize bone loss and may be useful in the primary and metastatic settings. The purpose of this review is to provide clear evidence-based strategies for the management of bone loss and its symptoms in breast cancer. A systematic review of clinical trials and meta-analyses published between 1996 and 2012 was conducted of MEDLINE and EMBASE. Reference lists were hand-searched for additional publications. Recommendations were developed based on the best available evidence. Zoledronate, pamidronate, clodronate, and denosumab are recommended for metastatic breast cancer patients; however, no one agent can be recommended over another. Zoledronate or any oral bisphosphonate and denosumab should be considered in primary breast cancer patients who are postmenopausal on aromatase inhibitor therapy and have a high risk of fracture and/or a low bone mineral density and in premenopausal primary breast cancer patients who become amenorrheic after therapy. No one agent can be recommended over another. BMAs are not currently recommended as adjuvant therapy in primary breast cancer for the purpose of improving survival, although a major Early Breast Cancer Cooperative Trialists’ Group meta-analysis is underway which may impact future practice. Adverse events can be managed with appropriate supportive care.

Comparative efficacy of bisphosphonates in metastatic breast and prostate cancer and multiple myeloma: a mixed-treatment meta-analysis

PURPOSE

A mixed-treatment comparison (MTC) was undertaken to compare the efficacy of zoledronic acid, clodronate, pamidronate, and ibandronate (i.v. and oral) in patients with skeletal-related events (SRE) secondary to metastatic breast and prostate cancer and multiple myeloma.

EXPERIMENTAL DESIGN

Studies of bisphosphonates in the three malignancies were identified and SRE data were extracted. Outcomes from the MTC were expressed as the annual SRE rate and as the mean likelihood (probability) ratio for the rate of SREs during treatment with zoledronic acid compared with the other bisphosphonates.

RESULTS

A total of 17 studies were identified (7 breast, 3 prostate, and 7 multiple myeloma). Data were available for all bisphosphonates in breast cancer; no data were available for ibandronate (oral or i.v.) in prostate cancer or for oral ibandronate in multiple myeloma. The SRE rates in breast cancer were 1.60 for zoledronic acid, 1.67 for oral ibandronate (excess SRE rate, 4%), 1.70 for i.v. ibandronate (6%), 2.07 for pamidronate (29%), and 2.29 for clodronate (42%). In prostate cancer, the SRE rates were 0.83 for zoledronic acid, 1.11 for clodronate (35%), and 1.41 for pamidronate (71%). In multiple myeloma, the SRE rates were 1.43 for zoledronic acid, 1.64 for pamidronate (15%), 1.90 for clodronate (33%), and 2.49 for i.v. ibandronate (75%).

CONCLUSIONS

Zoledronic acid seems to be the most efficacious bisphosphonate for reducing the risk of SREs in patients with cancer of the breast or prostate and those with multiple myeloma.

German Adjuvant Intergroup Node-Positive Study: A Phase III Trial to Compare Oral Ibandronate Versus Observation in Patients With High-Risk Early Breast Cancer

Purpose

Bisphosphonates prevent skeletal-related events in patients with metastatic breast cancer. Their effect in early breast cancer is controversial. Ibandronate is an orally and intravenously available amino-bisphosphonate with a favorable toxicity profile. It therefore qualifies as potential agent for adjuvant use.

Patients and Methods

The GAIN (German Adjuvant Intergroup Node-Positive) study was an open-label, randomized, controlled phase III trial with a 2 × 2 factorial design. Patients with node-positive early breast cancer were randomly assigned 1:1 to two different dose-dense chemotherapy regimens and 2:1 to ibandronate 50 mg per day orally for 2 years or observation. In all, 2,640 patients and 728 events were estimated to be required to demonstrate an increase in disease-free survival (DFS) by ibandronate from 75% to 79.5% by using a two-sided α = .05 and 1-β of 80%. We report here the efficacy analysis for ibandronate, which was released by the independent data monitoring committee because the futility boundary was not crossed after 50% of the required DFS events were observed.

Results

Between June 2004 and August 2008, 2,015 patients were randomly assigned to ibandronate and 1,008 to observation. Patients randomly assigned to ibandronate showed no superior DFS or overall survival (OS) compared with patients randomly assigned to observation (DFS: hazard ratio, 0.945; 95% CI, 0.768 to 1.161; P = .589; OS: HR, 1.040; 95% CI, 0.763 to 1.419; P = .803). DFS was numerically longer if ibandronate was used in patients younger than 40 years or older than 60 years compared with patients age 40 to 59 years (test for interaction P = .093).

Conclusion

Adjuvant treatment with oral ibandronate did not improve outcome of patients with high-risk early breast cancer who received dose-dense chemotherapy.

A primer of bone metastases management in breast cancer patients

Bone is the most common site for distant spread of breast cancer. Following a diagnosis of metastatic bone disease, patients can suffer from significant morbidity because of pain and skeletal related events (SRES). Bisphosphonates are potent inhibitors of osteoclastic function and the mainstay of bone-directed therapy for bone metastases. The aims of bisphosphonates are to prevent and delay SRES, to reduce bone pain, and to improve quality of life. Bisphosphonate therapy appears to have revolutionized treatment of bone metastases, but bisphosphonate use has several limitations. Those limitations include the high cost of the agents and the need for return trips to the clinic for intravenous treatment. Moreover, many uncertainties surround bisphosphonate use-for example, the timing of bisphosphonate initiation, the choice of bisphosphonate to use, the optimal duration of treatment, and the appropriate means to identify patients who will and will not benefit. In addition, potentially serious adverse effects have been associated with bisphosphonate use-for example, renal toxicity, gastrointestinal side effects, and osteonecrosis of the jaw. The present review is intended as a primer for oncology specialists who treat patients with bone metastases secondary to breast cancer. It focuses on bisphosphonate treatment guidelines, the evidence for those guidelines, and a discussion of new therapeutic agents. It also discusses the use of biochemical markers of bone metabolism, which show promise for predicting the risk of a patient's developing a SRE and of benefiting from bisphosphonate treatment.

Use of ibandronate in the prevention of skeletal events in metastatic breast cancer

Bone metastasis from breast cancer often cause significant morbidity including pain, impaired mobility, pathological fracture, and spinal cord compression. Bisphosphonates play an important role in preventing these skeletal related events and are the standard of care for patients with bone metastasis from breast cancer. Ibandronate is a highly potent bisphosphonate available in both intravenous and oral preparations. It has been shown in clinical trials to be effective in reducing skeletal complications and also significantly improve quality of life up to 96 weeks. Unlike other intravenous bisphosphonates, ibandronate has minimal renal toxicity, allowing safe outpatient administration, reducing the need for hospital attendance and safety monitoring. Early trials have shown ibandronate may also be effective in high doses for palliation of opioid-resistant pain from bone metastasis, and as a second-line agent in patients developing a skeletal complication whilst receiving another bisphosphonate.

Optimal management of bone metastases in breast cancer patients

Bone metastasis in breast cancer is a significant clinical problem. It not only indicates incurable disease with a guarded prognosis, but is also associated with skeletal-related morbidities including bone pain, pathological fractures, spinal cord compression, and hypercalcemia. In recent years, the mechanism of bone metastasis has been further elucidated. Bone metastasis involves a vicious cycle of close interaction between the tumor and the bone microenvironment. In patients with bone metastases, the goal of management is to prevent further skeletal-related events, manage complications, reduce bone pain, and improve quality of life. Bisphosphonates are a proven therapy for the above indications. Recently, a drug of a different class, the RANK ligand antibody, denosumab, has been shown to reduce skeletal-related events more than the bisphosphonate, zoledronic acid. Other strategies of clinical value may include surgery, radiotherapy, radiopharmaceuticals, and, of course, effective systemic therapy. In early breast cancer, bisphosphonates may have an antitumor effect and prevent both bone and non-bone metastases. Whilst two important Phase III trials with conflicting results have led to controversy in this topic, final results from these and other key Phase III trials must still be awaited before a firm conclusion can be drawn about the use of bisphosphonates in this setting. Advances in bone markers, predictive biomarkers, multi-imaging modalities, and the introduction of novel agents have ushered in a new era of proactive management for bone metastases in breast cancer.

Serum N-Terminal Propeptide of Collagen Type I is Associated with the Number of Bone Metastases in Breast and Prostate Cancer and Correlates to Other Bone Related Markers

Background

A number of biomarkers have been proven potentially useful for their ability to indicate bone metastases (BM) in cancer patients. The aim of this study was to investigate the relative utility of a newly developed N-terminal propeptide of collagen type I (PINP) human serum assay for the detection of BM in cancer patients. This assay has a corresponding rat PINP assay which in the future might help in translational science between rodent and human trials.

Methods

Participants were 161 prostate, lung and breast cancer patients stratified by number of BM (Soloway score). PINP was assessed and correlated to number of BM. Additionally, the PINP marker was correlated to bone resorption of young (ALPHA CTX-I)- and aged bone (BETA CTX-I); number of osteoclasts (Tartrate-resistant acid phosphatase 5b, TRACP5B) and osteoclast activity (CTX-I/ TRACP5B).

Results

PINP was significantly elevated in breast- and prostate cancer patients +BM, compared to −BM (P < 0.001), however not in lung cancer patients. A strong linear association was seen between PINP and the number of BMs. Significant elevation of PINP was observed at Soloway scores 1–4 (<0 BM) compared with score 0 (0 BM) (P < 0.001). The correlation between bone resorption of young bone or aged bone and bone formation was highly significant in patients +BM and −BM (P < 0.0001).

Conclusions

Data suggest that the present PINP potentially could determine skeletal involvement in patients with breast or prostate cancer. Correlations suggested that coupling between bone resorption and bone formation was maintained in breast- and prostate cancer patients.

Recent advances in the use of serological bone formation markers to monitor callus development and fracture healing

The failure of an osseous fracture to heal, or the development of a nonunion, is common; however, current diagnostic measures lack the capability of early and reliable detection of such events. Analyses of radiographic imaging and clinical examination, in combination, remain the gold standard for diagnosis; however, these methods are not reliable for early detection. Delayed diagnosis of a nonunion is costly from both the patient and treatment standpoints. In response, repeated efforts have been made to identify bone metabolic markers as diagnostic or prognostic tools for monitoring bone healing. Thus far, the evidence regarding a correlation between the kinetics of most bone metabolic markers and nonunion is very limited. With the aim of classifying the role of biological pathways of bone metabolism and of understanding bone conditions in the development of osteoporosis, advances have been made in our knowledge of the molecular basis of bone remodeling, fracture healing, and its failure. Procollagen type I amino-terminal propeptide has been shown to be a reliable bone formation marker in osteoporosis therapy and its kinetics during fracture healing has been recently described. In this article, we suggest that procollagen type I amino-terminal propeptide presents a good opportunity for early detection of nonunion. We also review the role and potential of serum PINP, as well as other markers, as indications of fracture healing.

Use of aromatase inhibitors and bisphosphonates as an anticancer therapy in postmenopausal breast cancer

Breast cancer is a major cause of morbidity and mortality in postmenopausal women worldwide. Reducing the risk of distant disease recurrence is a primary goal of adjuvant endocrine therapy. As we await data from ongoing Phase III comparison trials, an emerging body of evidence demonstrates important differences between third-generation aromatase inhibitors, particularly with respect to potency and prevention of early distant metastases. Furthermore, a growing body of evidence demonstrates anticancer benefits of bisphosphonates in adjuvant breast cancer and other settings. This article outlines the proceedings from an Expert Panel meeting of regionally diverse breast cancer specialists regarding the appropriate use of aromatase inhibitors in postmenopausal hormone-responsive early breast cancer and bisphosphonates as anticancer therapy in adjuvant breast cancer.

Oral ibandronate in metastatic bone breast cancer: the Florence University experience and a review of the literature

Ibandronate is an amino-bisphosphonate approved in metastatic breast cancer to reduce skeletal complications and to alleviate bone pain. we report our experience about the safety of oral ibandronate and review the literature.We treated 44 patients and administered 524 cycles of oral ibandronate (a single cycle was defined as a 50 mg capsule once daily for 28 days) with a median of 12 cycles (range 6-24). At a median follow-up of 18.5 months (range 6-28) the mean pain score decreased from 1.59 (SD+/-0.97) at baseline to 0.41 (SD+/-0.72) after 48 weeks of treatment. The mean analgesic score was 1.89 (SD+/-1.37) at baseline and 1.46 (SD+/-1.62) after 48 weeks of treatment. Ibandronate was generally well-tolerated; we had no Grade 3-4 adverse events. No patients had deterioration of renal function. No patients developed bisphosphonate-associated osteonecrosis of the jaw. Our experience confirmed that ibandronate may be a useful and safe co-analgesic to conventional treatments for bone pain in selected metastatic breast cancer patients.

Bisphosphonates and RANK ligand inhibitors for the treatment and prevention of metastatic bone disease

Bisphosphonates (BPs) are potent inhibitors of osteoclast-mediated bone resorption, which is increased when cancer cells invade bone. BPs are an established treatment for cancer that has spread to bone, and effectively reduce pain and other skeletal-related events. New directions in metastatic bone disease (MBD) include personalised BP therapy, such as using bone markers to guide frequency of BP administration and bone targeting agents such as denosumab (AMG 162). Clinical trials strongly suggest that denosumab might play a defined role in the future management of MBD. In terms of potential anti-cancer activity, early data tentatively suggest that zoledronic acid might have a role to play in the prevention of metastatic disease, though whether this is a direct effect on cancer cells, or indirect via the bone marrow micro-environment, or both, is as yet undiscovered. The definitive answer as to the role of adjuvant BP in early cancer is being addressed, with over 20,000 patients with breast, prostate or lung cancer currently participating in adjuvant BP randomised trials. The results of these trials should be available in the next few years, and this will establish whether BPs given early in the course of cancer will be able to prevent the formation of metastases, bone or otherwise.

Bisphosphonates in breast cancer: teaching an old dog new tricks

PURPOSE OF REVIEW

Bisphosphonates are potent inhibitors of bone resorption that reduce the risk of skeletal complications and prevent treatment-induced bone loss. However, recent data suggest that bisphosphonate use in breast cancer may provide more than just supportive care and modify the course of the disease by disrupting the metastatic process.

RECENT FINDINGS

Research in the metastatic setting is focused on refining treatment, using bone markers to identify high-risk patients and define optimal schedules, potentially leading to personalized therapy. In the prevention of cancer treatment-induced bone loss (CTIBL), a large number of studies have demonstrated the efficacy of oral and intravenous bisphosphonates and recent guidelines have defined management strategies for CTIBL. Preclinical studies have reported direct antitumour effects of bisphosphonates, particularly in combination with chemotherapy. In the clinical setting the antitumour effect is less clear, but recent data suggest that zoledronic acid may modify the course of the disease and reduce disease recurrence.

SUMMARY

Bisphosphonates are comprehensively established in the treatment of metastatic bone disease and significantly reduce skeletal morbidity. Their role in the prevention of cancer treatment-induced bone disease is also defined. The potential antitumour and disease-modifying role of adjuvant bisphosphonates holds promise but results from ongoing studies must be awaited before this becomes standard practice.

A single pretreatment by zoledronic acid converts metastases from osteolytic to osteoblastic in the rat

Bone metastases are severe complications of cancers associated with increased morbidity, pain, risk fracture, and reduced life span for patients. Bisphosphonates emerged as a relief treatment in bone metastases. A single dose of zoledronic acid (78 microg/kg) was injected into six Copenhagen rats 4 days before receiving an intraosseous inoculation of metastatic anaplastic tumor of lymph node and lung cell (MLL) prostate cancer cells. Rat femurs were analyzed for changes by microCT and histomorphometry; trabecular volume, trabecular characteristics, osteoid parameters, osteoblastic surfaces, and osteoclast number were measured. Values were compared to a group of SHAM animals, a group of SHAM animals having received zoledronic acid and animals inoculated with MLL cells. All rats were euthanized after 1 month. MLL cells induced osteolysis in the metaphysis with extension of the tumor to soft tissues through cortical perforations. Zoledronic acid induced a marked osteosclerosis in the primary spongiosa in both SHAM and rats inoculated with MLL. Osteosclerosis was obtained in the secondary spongiosa of MLL rats. The bisphosphonate preserved cortical integrity in all animals, and no extension to soft tissues was observed in most animals. The number of osteoclasts was elevated, indicating that there was no apoptosis of osteoclasts but they became inactive. Osteosclerosis was associated with increased osteoblastic surfaces. A single zoledronic acid injection turned osteolytic metastases into osteosclerotic and preserved cortical integrity.

New and emerging treatments for osteoporosis

A variety of new treatments for osteoporosis have become available within the last several years, and a number of emerging treatments remain in late clinical stage development. New and emerging treatments include more potent members, or more convenient formulations, of existing classes of therapy, but a number of the emerging treatments are first-generation compounds addressing specific therapeutic targets based on recent advances in understanding of basic bone biology. These new and emerging treatments include agents with anticatabolic effects, compounds with anabolic effects, and one agent possibly containing both anticatabolic and anabolic effects. The increasing variety of new and emerging treatments increases the possibility that effective therapy will be targeted to the specific needs of the individual patient.

Preserving functional independence in elderly patients with cancer-associated bone disease: the role of zoledronic acid

Increases in life expectancy in the developed world will inevitably lead to larger numbers of elderly patients with cancer-associated (malignant) bone disease. Most elderly patients with metastatic cancer also suffer from numerous comorbidities. The management of bone health in this setting requires special consideration. This article centers on malignant bone disease in the elderly and the role of bisphosphonates in geriatric oncology. The challenges involved in the treatment of older patients with bone metastases are described, and the potential utility of bisphosphonates, such as zoledronic acid, is discussed. Moreover, recent data from several large clinical trials suggest that zoledronic acid provides additional benefits, including antitumor effects that may extend beyond the preservation of bone health and prevention of skeletal-related events.

Treatment Options for Breast Cancer and Bone Metastases

The most common destination for breast cancer metastases is bone. If bone metastases are detected, treatment algorithms should include the continuation of cytoreductive therapy with the addition of treatment to counter skeletal-related events, including bone pain. The range of current treatment options includes bisphosphonates, surgical intervention to improve structural integrity and palliative focal radiotherapy. This article focuses on the role of bisphosphonate therapy in metastatic breast cancer. Bisphosphonate therapy significantly reduces the impact of skeletal-related events, reduces bone pain and increases patient quality of life. Our current understanding is that bisphosphonates may also disrupt the metastatic process and reduce the development of bone lesions. Ultimately, this may lead to further expansion of bisphosphonate-based therapy in the future.

Zoledronic acid : a review of its use in the management of bone metastases of malignancy

Zoledronic acid (Zometa), a third-generation amino-bisphosphonate, has been approved in the US, the EU and many other countries worldwide for the prevention of skeletal-related events in patients with bone metastases of malignancy. In several well designed trials, zoledronic acid 4 mg administered as a 15-minute infusion every 3-4 weeks was effective in reducing the occurrence of skeletal complications in patients with bone metastases secondary to multiple myeloma, breast cancer or prostate cancer. Zoledronic acid was as effective as pamidronic acid in reducing the occurrence of skeletal complications in patients with multiple myeloma or breast cancer. In patients with solid tumours other than breast or prostate cancer, zoledronic acid did not show significant clinical benefit over placebo in terms of the primary endpoint; however, some benefit of therapy in terms of secondary endpoints was observed with zoledronic acid relative to placebo. Its efficacy in a broad range of tumours and short infusion time (15 minutes) are an advantage over other available bisphosphonates. Modelled pharmacoeconomic analyses in patients with breast cancer suggested that zoledronic acid therapy is cost effective relative to no therapy with regard to the cost per quality-adjusted life-year (QALY) gained; however, results were mixed when zoledronic acid was compared with other commonly used bisphosphonates. Zoledronic acid is generally well tolerated; the risk of osteonecrosis of the jaw may be minimized by adhering to recommendations regarding dental therapy. Additional efficacy and economic data are required to definitively position zoledronic acid with respect to other bisphosphonates. Nevertheless, available clinical data indicate that zoledronic acid is an effective treatment option for the management of bone metastases of malignancy.

Dual focal adhesion kinase/Pyk2 inhibitor has positive effects on bone tumors: implications for bone metastases

BACKGROUND

Lytic bone metastases occur frequently in cancer patients and present major clinical issues including lack of effective therapies. The mechanism of lytic bone metastases involves interactions between tumor cells, bone matrix, and bone cells. Both focal adhesion kinase (FAK) and Pyk2 are implicated in the biology and physiology of bone and cancer.

METHODS

The efficacy of PF-562,271 was evaluated using MDA-MB-231 cells implanted in the tibia of nude rats. The drug was administered orally at a dose of 5 mg/kg, 7 days per week for 28 days. Serum and urine biomarkers, imaging, and histologic techniques were deployed to monitor tumor take rate, disease progression, and response to therapy.

RESULTS

The compound was well tolerated. Both compound-treated groups demonstrated significant and similar increases in osteocalcin and cancellous bone parameters. Radiographic evaluation of tumor-bearing tibiae revealed tumor expansion in nontreated rats compared with a decrease in tumor growth and signs of bone healing in rats treated with PF-562,271. Tartrate-resistant acid phosphatase and fluorescent in situ hybridization analysis revealed that the majority of bone resorption at the tumor site was performed by osteoclasts of rat origin.

CONCLUSIONS

The oral administration of PF-562,271 at a dose of 5 mg/kg suppressed the growth and local spread of intratibial tumors and restored tumor-induced bone loss. The unique ability of PF-562,271 to both curb tumor growth and safely increase bone formation may be an effective therapy for many cancer patients with bone metastases and cancer-associated osteoporosis.

Oral versus intravenous ibandronic acid: a comparison of treatment options for metastatic bone disease

PURPOSE

This trial is the first to compare directly the clinical response to and safety of oral and intravenous (IV) ibandronic acid for metastatic bone disease.

METHODS

Patients > or =18 years with breast, prostate, lung, urogenital or colon cancer received IV ibandronic acid 6 mg infused over 15 min every 28 days or oral ibandronic acid 50 mg/day. Clinical response was determined using bone scintigraphy, radiography and serum C-terminal telopeptide of type I collagen (S-CTX) at months 3-6. Adverse events and biochemical safety measures were recorded.

RESULTS

A total of 84.6 and 88.5% of patients had a complete/partial response to IV and oral ibandronic acid, respectively. Median percentage decreases in S-CTX were -39 and -35%, respectively. Bone pain scores decreased and analgesic use increased from month 0-3 and were stable from months 3-6. Both formulations improved physical and functioning scores.

CONCLUSION

Oral and IV ibandronic acid for bone metastases have similar efficacy and tolerability.

New strategies for the treatment of metastatic bone disease

The introduction of bisphosphonates represents an important advance in the care of patients with metastatic bone disease. Nonetheless, we remain unable to prevent metastatic bone destruction. This review will discuss several novel therapies, including inhibitors of receptor activator of nuclear factor-kappabeta, c-Src, mammalian target of rapamycin, cathepsin K, and alpha(5)beta(3) integrins, which could improve our control over this devastating complication.

Guidance on the use of bisphosphonates in solid tumours: recommendations of an international expert panel

Bisphosphonates (BP) prevent, reduce, and delay cancer-related skeletal complications in patients, and have substantially decreased the prevalence of such events since their introduction. Today, a broad range of BP with differences in potency, efficacy, dosing, and administration as well as approved indications is available. In addition, results of clinical trials investigating the efficacy of BP in cancer treatment-induced bone loss (CTIBL) have been recently published. The purpose of this paper is to review the current evidence on the use of BP in solid tumours and provide clinical recommendations. An interdisciplinary expert panel of clinical oncologists and of specialists in metabolic bone diseases assessed the widespread evidence and information on the efficacy of BP in the metastatic and nonmetastatic setting, as well as ongoing research on the adjuvant use of BP. Based on available evidence, the panel recommends amino-bisphosphonates for patients with metastatic bone disease from breast cancer and zoledronic acid for patients with other solid tumours as primary disease. Dosing of BP should follow approved indications with adjustments if necessary. While i.v. administration is most often preferable, oral administration (clodronate, IBA) may be considered for breast cancer patients who cannot or do not need to attend regular hospital care. Early-stage cancer patients at risk of developing CTIBL should be considered for preventative BP treatment. The strongest evidence in this setting is now available for ZOL. Overall, BP are well-tolerated, and most common adverse events are influenza-like syndrome, arthralgia, and when used orally, gastrointestinal symptoms. The dose of BP may need to be adapted to renal function and initial creatinine clearance calculation is mandatory according to the panel for use of any BP. Subsequent monitoring is recommended for ZOL and PAM, as described by the regulatory authority guidelines. Patients scheduled to receive BP (mainly every 3-4 weeks i.v.) should have a dental examination and be advised on appropriate measures for reducing the risk of jaw osteonecrosis. BP are well established as supportive therapy to reduce the frequency and severity of skeletal complications in patients with bone metastases from different cancers.