Effect of oral clodronate on bone mass, bone turnover and subsequent metastases in women with primary breast cancer

Bone-modifying agents for reducing bone loss in women with early and locally advanced breast cancer: a network meta-analysis

BACKGROUND

Bisphosphonates and receptor activator of nuclear factor-kappa B ligand (RANKL)-inhibitors are amongst the bone-modifying agents used as supportive treatment in women with breast cancer who do not have bone metastases. These agents aim to reduce bone loss and the risk of fractures. Bisphosphonates have demonstrated survival benefits, particularly in postmenopausal women.

OBJECTIVES

To assess and compare the effects of different bone-modifying agents as supportive treatment to reduce bone mineral density loss and osteoporotic fractures in women with breast cancer without bone metastases and generate a ranking of treatment options using network meta-analyses (NMAs).

SEARCH METHODS

We identified studies by electronically searching CENTRAL, MEDLINE and Embase until January 2023. We searched various trial registries and screened abstracts of conference proceedings and reference lists of identified trials.

SELECTION CRITERIA

We included randomised controlled trials comparing different bisphosphonates and RANKL-inihibitors with each other or against no further treatment or placebo for women with breast cancer without bone metastases.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed the risk of bias of included studies and certainty of evidence using GRADE. Outcomes were bone mineral density, quality of life, overall fractures, overall survival and adverse events. We conducted NMAs and generated treatment rankings.

MAIN RESULTS

Forty-seven trials (35,163 participants) fulfilled our inclusion criteria; 34 trials (33,793 participants) could be considered in the NMA (8 different treatment options). Bone mineral density We estimated that the bone mineral density of participants with no treatment/placebo measured as total T-score was -1.34. Evidence from the NMA (9 trials; 1166 participants) suggests that treatment with ibandronate (T-score -0.77; MD 0.57, 95% CI -0.05 to 1.19) may slightly increase bone mineral density (low certainty) and treatment with zoledronic acid (T-score -0.45; MD 0.89, 95% CI 0.62 to 1.16) probably slightly increases bone mineral density compared to no treatment/placebo (moderate certainty). Risedronate (T-score -1.08; MD 0.26, 95% CI -0.32 to 0.84) may result in little to no difference compared to no treatment/placebo (low certainty). We are uncertain whether alendronate (T-score 2.36; MD 3.70, 95% CI -2.01 to 9.41) increases bone mineral density compared to no treatment/placebo (very low certainty). Quality of life No quantitative analyses could be performed for quality of life, as only three studies reported this outcome. All three studies showed only minimal differences between the respective interventions examined. Overall fracture rate We estimated that 70 of 1000 participants with no treatment/placebo had fractures. Evidence from the NMA (16 trials; 19,492 participants) indicates that treatment with clodronate or ibandronate (42 of 1000; RR 0.60, 95% CI 0.39 to 0.92; 40 of 1000; RR 0.57, 95% CI 0.38 to 0.86, respectively) decreases the number of fractures compared to no treatment/placebo (high certainty). Denosumab or zoledronic acid (51 of 1000; RR 0.73, 95% CI 0.52 to 1.01; 55 of 1000; RR 0.79, 95% CI 0.56 to 1.11, respectively) probably slightly decreases the number of fractures; and risedronate (39 of 1000; RR 0.56, 95% CI 0.15 to 2.16) probably decreases the number of fractures compared to no treatment/placebo (moderate certainty). Pamidronate (106 of 1000; RR 1.52, 95% CI 0.75 to 3.06) probably increases the number of fractures compared to no treatment/placebo (moderate certainty). Overall survival We estimated that 920 of 1000 participants with no treatment/placebo survived overall. Evidence from the NMA (17 trials; 30,991 participants) suggests that clodronate (924 of 1000; HR 0.95, 95% CI 0.77 to 1.17), denosumab (927 of 1000; HR 0.91, 95% CI 0.69 to 1.21), ibandronate (915 of 1000; HR 1.06, 95% CI 0.83 to 1.34) and zoledronic acid (925 of 1000; HR 0.93, 95% CI 0.76 to 1.14) may result in little to no difference regarding overall survival compared to no treatment/placebo (low certainty). Additionally, we are uncertain whether pamidronate (905 of 1000; HR 1.20, 95% CI 0.81 to 1.78) decreases overall survival compared to no treatment/placebo (very low certainty). Osteonecrosis of the jaw We estimated that 1 of 1000 participants with no treatment/placebo developed osteonecrosis of the jaw. Evidence from the NMA (12 trials; 23,527 participants) suggests that denosumab (25 of 1000; RR 24.70, 95% CI 9.56 to 63.83), ibandronate (6 of 1000; RR 5.77, 95% CI 2.04 to 16.35) and zoledronic acid (9 of 1000; RR 9.41, 95% CI 3.54 to 24.99) probably increases the occurrence of osteonecrosis of the jaw compared to no treatment/placebo (moderate certainty). Additionally, clodronate (3 of 1000; RR 2.65, 95% CI 0.83 to 8.50) may increase the occurrence of osteonecrosis of the jaw compared to no treatment/placebo (low certainty). Renal impairment We estimated that 14 of 1000 participants with no treatment/placebo developed renal impairment. Evidence from the NMA (12 trials; 22,469 participants) suggests that ibandronate (28 of 1000; RR 1.98, 95% CI 1.01 to 3.88) probably increases the occurrence of renal impairment compared to no treatment/placebo (moderate certainty). Zoledronic acid (21 of 1000; RR 1.49, 95% CI 0.87 to 2.58) probably increases the occurrence of renal impairment while clodronate (12 of 1000; RR 0.88, 95% CI 0.55 to 1.39) and denosumab (11 of 1000; RR 0.80, 95% CI 0.54 to 1.19) probably results in little to no difference regarding the occurrence of renal impairment compared to no treatment/placebo (moderate certainty).

AUTHORS' CONCLUSIONS

When considering bone-modifying agents for managing bone loss in women with early or locally advanced breast cancer, one has to balance between efficacy and safety. Our findings suggest that bisphosphonates (excluding alendronate and pamidronate) or denosumab compared to no treatment or placebo likely results in increased bone mineral density and reduced fracture rates. Our survival analysis that included pre and postmenopausal women showed little to no difference regarding overall survival. These treatments may lead to more adverse events. Therefore, forming an overall judgement of the best ranked bone-modifying agent is challenging. More head-to-head comparisons, especially comparing denosumab with any bisphosphonate, are needed to address gaps and validate the findings of this review.

Potential Adverse Effect of Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) on Bisphosphonate Efficacy: An Exploratory Post Hoc Analysis From a Randomized Controlled Trial of Clodronate

Nonsteroidal anti-inflammatory drugs (NSAIDs) have been reported to have weak but beneficial effects on bone health, including fracture risk, but many epidemiological studies are likely confounded. We explored the relationship between NSAIDs and fracture risk in a post hoc analysis of a well-documented, randomized, placebo-controlled study of the bisphosphonate, clodronate, in which treatment reduced osteoporotic fracture risk by 23%. Concurrent medication use at baseline was used to identify those prescribed oral NSAIDs. Only verified, incident fractures were included in the analysis. A total of 1082 (20.8%) women reported use of NSAIDs at baseline. They were slightly, but significantly, younger (mean 79 versus 80 years, p = 0.004), heavier (mean 66.7 versus 64.7 kg, p < 0.001) than nonusers, with slightly higher femoral neck bone mineral density (FN-BMD, 0.66 versus 0.64 g/cm2 , p < 0.001). In an adjusted model, NSAID use was associated with a significant increase in osteoporotic fracture risk over the 3-year study period (hazard ratio [HR] 1.27; 95% confidence interval [CI], 1.01-1.62; p = 0.039). However, this increase in risk was not statistically significant in the placebo group (HR 1.11; 95% CI, 0.81-1.52). In women receiving clodronate, the effect of the bisphosphonate to reduce osteoporotic fracture risk was not observed in those receiving NSAIDs (HR 0.95; 95% CI, 0.65-1.41; p = 0.81) in contrast to those not using NSAIDs (HR 0.71; 95% CI, 0.58-0.89; p = 0.002). In a subset with hip BMD repeated at 3 years, BMD loss during clodronate therapy was greater in those women receiving NSAIDs than in nonusers (eg, total hip -2.75% versus -1.27%, p = 0.078; femoral neck -3.06% versus -1.12%, p = 0.028), and was not significantly different from that observed in women receiving placebo. The efficacy of the bisphosphonate, clodronate, to reduce fracture risk was largely negated in those receiving NSAIDs. Although the mechanism is unclear, this clinically significant observation requires exploration in studies of commonly used bisphosphonates. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Associations Between Serum Bone Biomarkers in Early Breast Cancer and Development of Bone Metastasis: Results From the AZURE (BIG01/04) Trial

Background

Adjuvant therapies can prevent/delay bone metastasis development in breast cancer. We investigated whether serum bone turnover markers in early disease have clinical utility in identifying patients with a high risk of developing bone metastasis.

Methods

Markers of bone formation (N-terminal propeptide of type-1 collagen [P1NP]) and bone resorption (C-telopeptide of type-1 collagen [CTX], pyridinoline cross-linked carboxy-terminal telopeptide of type-1 collagen [1-CTP]) were measured in baseline (pretreatment blood samples from 872 patients from a large randomized trial of adjuvant zoledronic acid (AZURE-ISRCTN79831382) in early breast cancer. Cox proportional hazards regression and cumulative incidence functions (adjusted for factors having a statistically significant effect on outcome) were used to investigate prognostic and predictive associations between recurrence events, bone marker levels, and clinical variables. All statistical tests were two-sided.

Results

When considered as continuous variables (log transformed), P1NP, CTX, and 1-CTP were each prognostic for future bone recurrence at any time (P = .006, P = .009, P = .008, respectively). Harrell’s c-indices were a P1NP of 0.57 (95% confidence interval [CI] = 0.51 to 0.63), CTX of 0.57 (95% CI = 0.51 to 0.62), and 1-CTP of 0.57 (95% CI = 0.52 to 0.63). In categorical analyses based on the normal range, high baseline P1NP (>70 ng/mL) and CTX (>0.299 ng/mL), but not 1-CTP (>4.2 ng/mL), were also prognostic for future bone recurrence (P = .03, P = .03, P = .10, respectively). None of the markers were prognostic for overall distant recurrence; that is, they were bone metastasis specific, and none of the markers were predictive of treatment benefit from zoledronic acid.

Conclusions

Serum P1NP, CTX, and 1-CTP are clinically useful, easily measured markers that show good prognostic ability (though low-to-moderate discrimination) for bone-specific recurrence and are worthy of further study.

Bisphosphonates and other bone agents for breast cancer

BACKGROUND

Bone is the most common site of metastatic disease associated with breast cancer (BC). Bisphosphonates inhibit osteoclast-mediated bone resorption, and novel targeted therapies such as denosumab inhibit other key bone metabolism pathways. We have studied these agents in both early breast cancer and advanced breast cancer settings. This is an update of the review originally published in 2002 and subsequently updated in 2005 and 2012.

OBJECTIVES

To assess the effects of bisphosphonates and other bone agents in addition to anti-cancer treatment: (i) in women with early breast cancer (EBC); (ii) in women with advanced breast cancer without bone metastases (ABC); and (iii) in women with metastatic breast cancer and bone metastases (BCBM).

SEARCH METHODS

In this review update, we searched Cochrane Breast Cancer's Specialised Register, CENTRAL, MEDLINE, Embase, the World Health Organization's International Clinical Trials Registry Platform (WHO ICTRP) and ClinicalTrials.gov on 19 September 2016.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing: (a) one treatment with a bisphosphonate/bone-acting agent with the same treatment without a bisphosphonate/bone-acting agent; (b) treatment with one bisphosphonate versus treatment with a different bisphosphonate; (c) treatment with a bisphosphonate versus another bone-acting agent of a different mechanism of action (e.g. denosumab); and (d) immediate treatment with a bisphosphonate/bone-acting agent versus delayed treatment of the same bisphosphonate/bone-acting agent.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data, and assessed risk of bias and quality of the evidence. The primary outcome measure was bone metastases for EBC and ABC, and a skeletal-related event (SRE) for BCBM. We derived risk ratios (RRs) for dichotomous outcomes and the meta-analyses used random-effects models. Secondary outcomes included overall survival and disease-free survival for EBC; we derived hazard ratios (HRs) for these time-to-event outcomes where possible. We collected toxicity and quality-of-life information. GRADE was used to assess the quality of evidence for the most important outcomes in each treatment setting.

MAIN RESULTS

We included 44 RCTs involving 37,302 women.In women with EBC, bisphosphonates were associated with a reduced risk of bone metastases compared to placebo/no bisphosphonate (RR 0.86, 95% confidence interval (CI) 0.75 to 0.99; P = 0.03, 11 studies; 15,005 women; moderate-quality evidence with no significant heterogeneity). Bisphosphonates provided an overall survival benefit with time-to-event data (HR 0.91, 95% CI 0.83 to 0.99; P = 0.04; 9 studies; 13,949 women; high-quality evidence with evidence of heterogeneity). Subgroup analysis by menopausal status showed a survival benefit from bisphosphonates in postmenopausal women (HR 0.77, 95% CI 0.66 to 0.90; P = 0.001; 4 studies; 6048 women; high-quality evidence with no evidence of heterogeneity) but no survival benefit for premenopausal women (HR 1.03, 95% CI 0.86 to 1.22; P = 0.78; 2 studies; 3501 women; high-quality evidence with no heterogeneity). There was evidence of no effect of bisphosphonates on disease-free survival (HR 0.94, 95% 0.87 to 1.02; P = 0.13; 7 studies; 12,578 women; high-quality evidence with significant heterogeneity present) however subgroup analyses showed a disease-free survival benefit from bisphosphonates in postmenopausal women only (HR 0.82, 95% CI 0.74 to 0.91; P < 0.001; 7 studies; 8314 women; high-quality evidence with no heterogeneity). Bisphosphonates did not significantly reduce the incidence of fractures when compared to placebo/no bisphosphonates (RR 0.77, 95% CI 0.54 to 1.08, P = 0.13, 6 studies, 7602 women; moderate-quality evidence due to wide confidence intervals). We await mature overall survival and disease-free survival results for denosumab trials.In women with ABC without clinically evident bone metastases, there was no evidence of an effect of bisphosphonates on bone metastases (RR 0.96, 95% CI 0.65 to 1.43; P = 0.86; 3 studies; 330 women; moderate-quality evidence with no heterogeneity) or overall survival (RR 0.89, 95% CI 0.73 to 1.09; P = 0.28; 3 studies; 330 women; high-quality evidence with no heterogeneity) compared to placebo/no bisphosphonates however the confidence intervals were wide. One study reported a trend towards an extended period of time without a SRE with bisphosphonate compared to placebo (low-quality evidence). One study reported quality of life and there was no apparent difference in scores between bisphosphonate and placebo (moderate-quality evidence).In women with BCBM, bisphosphonates reduced the SRE risk by 14% (RR 0.86, 95% CI 0.78 to 0.95; P = 0.003; 9 studies; 2810 women; high-quality evidence with evidence of heterogeneity) compared with placebo/no bisphosphonates. This benefit persisted when administering either intravenous or oral bisphosphonates versus placebo. Bisphosphonates delayed the median time to a SRE with a median ratio of 1.43 (95% CI 1.29 to 1.58; P < 0.00001; 9 studies; 2891 women; high-quality evidence with no heterogeneity) and reduced bone pain (in 6 out of 11 studies; moderate-quality evidence) compared to placebo/no bisphosphonate. Treatment with bisphosphonates did not appear to affect overall survival (RR 1.01, 95% CI 0.91 to 1.11; P = 0.85; 7 studies; 1935 women; moderate-quality evidence with significant heterogeneity). Quality-of-life scores were slightly better with bisphosphonates than placebo at comparable time points (in three out of five studies; moderate-quality evidence) however scores decreased during the course of the studies. Denosumab reduced the risk of developing a SRE compared with bisphosphonates by 22% (RR 0.78, 0.72 to 0.85; P < 0.001; 3 studies, 2345 women). One study reported data on overall survival and observed no difference in survival between denosumab and bisphosphonate.Reported toxicities across all settings were generally mild. Osteonecrosis of the jaw was rare, occurring less than 0.5% in the adjuvant setting (high-quality evidence).

AUTHORS' CONCLUSIONS

For women with EBC, bisphosphonates reduce the risk of bone metastases and provide an overall survival benefit compared to placebo or no bisphosphonates. There is preliminary evidence suggestive that bisphosphonates provide an overall survival and disease-free survival benefit in postmenopausal women only when compared to placebo or no bisphosphonate. This was not a planned subgroup for these early trials, and we await the completion of new large clinical trials assessing benefit for postmenopausal women. For women with BCBM, bisphosphonates reduce the risk of developing SREs, delay the median time to an SRE, and appear to reduce bone pain compared to placebo or no bisphosphonate.

Use of Adjuvant Bisphosphonates and Other Bone-Modifying Agents in Breast Cancer: A Cancer Care Ontario and American Society of Clinical Oncology Clinical Practice Guideline

Purpose To make recommendations regarding the use of bisphosphonates and other bone-modifying agents as adjuvant therapy for patients with breast cancer. Methods Cancer Care Ontario and ASCO convened a Working Group and Expert Panel to develop evidence-based recommendations informed by a systematic review of the literature. Results Adjuvant bisphosphonates were found to reduce bone recurrence and improve survival in postmenopausal patients with nonmetastatic breast cancer. In this guideline, postmenopausal includes patients with natural menopause or that induced by ovarian suppression or ablation. Absolute benefit is greater in patients who are at higher risk of recurrence, and almost all trials were conducted in patients who also received systemic therapy. Most studies evaluated zoledronic acid or clodronate, and data are extremely limited for other bisphosphonates. While denosumab was found to reduce fractures, long-term survival data are still required. Recommendations It is recommended that, if available, zoledronic acid (4 mg intravenously every 6 months) or clodronate (1,600 mg/d orally) be considered as adjuvant therapy for postmenopausal patients with breast cancer who are deemed candidates for adjuvant systemic therapy. Further research comparing different bone-modifying agents, doses, dosing intervals, and durations is required. Risk factors for osteonecrosis of the jaw and renal impairment should be assessed, and any pending dental or oral health problems should be dealt with prior to starting treatment. Data for adjuvant denosumab look promising but are currently insufficient to make any recommendation. Use of these agents to reduce fragility fractures in patients with low bone mineral density is beyond the scope of the guideline. Recommendations are not meant to restrict such use of bone-modifying agents in these situations. Additional information at www.asco.org/breast-cancer-adjuvant-bisphosphonates-guideline , www.asco.org/guidelineswiki , https://www.cancercareontario.ca/guidelines-advice/types-of-cancer/breast .

Pharmacologic management of bone-related complications and bone metastases in postmenopausal women with hormone receptor-positive breast cancer

There is a high risk for bone loss and skeletal-related events, including bone metastases, in postmenopausal women with hormone receptor-positive breast cancer. Both the disease itself and its therapeutic treatments can negatively impact bone, resulting in decreases in bone mineral density and increases in bone loss. These negative effects on the bone can significantly impact morbidity and mortality. Effective management and minimization of bone-related complications in postmenopausal women with hormone receptor-positive breast cancer remain essential. This review discusses the current understanding of molecular and biological mechanisms involved in bone turnover and metastases, increased risk for bone-related complications from breast cancer and breast cancer therapy, and current and emerging treatment strategies for managing bone metastases and bone turnover in postmenopausal women with hormone receptor-positive breast cancer.

Bisphosphonates for cancer treatment: Mechanisms of action and lessons from clinical trials

A growing body of evidence points toward an important anti-cancer effect of bisphosphonates, a group of inexpensive, safe, potent, and long-term stable pharmacologicals that are widely used as osteoporosis drugs. To date, they are already used in the prevention of complications of bone metastases. Because the bisphosphonates can also reduce mortality in among other multiple myeloma, breast, and prostate cancer patients, they are now thoroughly studied in oncology. In particular, the more potent nitrogen-containing bisphosphonates have the potential to improve prognosis. The first part of this review will elaborate on the direct and indirect anti-tumoral effects of bisphosphonates, including induction of tumor cell apoptosis, inhibition of tumor cell adhesion and invasion, anti-angiogenesis, synergism with anti-neoplastic drugs, and enhancement of immune surveillance (e.g., through activation of γδ T cells and targeting macrophages). In the second part, we shed light on the current clinical position of bisphosphonates in the treatment of hematological and solid malignancies, as well as on ongoing and completed clinical trials investigating the therapeutic effect of bisphosphonates in cancer. Based on these recent data, the role of bisphosphonates is expected to further expand in the near future outside the field of osteoporosis and to open up new avenues in the treatment of malignancies.

Development and dissolution studies of bisphosphonate (clodronate)-containing hydroxyapatite-polylactic acid biocomposites for slow drug delivery

An increase in clinical demand on the controlled release of bisphosphonates (BPs) due to complications associated with systemic administration, has been the current driving force on the development of BP drug-release systems. Bisphosphonates have the ability to bind to divalent metal ions, such as Ca²⁺ , in bone mineral and prevent bone resorption by influencing the apoptosis of osteoclasts. Localized delivery using biodegradable materials, such as polylactic acid (PLA) and hydroxyapatite (HAp), which are ideal in this approach, have been used in this study to investigate the dissolution of clodronate (non-nitrogen-containing bisphosphonate) in a new release system. The effects of coral structure-derived HAp and the release kinetics of the composites were evaluated. The release kinetics of clodronate from PLA-BP and PLA-HAp-BP systems seemed to follow the power law model described by Korsmeyer-Peppas. Drug release was quantified by ³¹ P-NMR with detection and quantification limits of 9.2 and 30.7 mM, respectively. The results suggest that these biocomposite systems could be tuned to release clodronate for both relatively short and prolonged period of time. In addition to drug delivery, the degradation of HAp supplies both Ca²⁺ and phosphate ions that can help in bone mineralization. Copyright © 2015 John Wiley & Sons, Ltd.

Bone turnover markers in serum and urine as diagnostic, prognostic and monitoring biomarkers of bone metastasis

Bone metastases are characterized by increased osteoblastic and/or osteolytic processes depending on the tumor type. The altogether destructive effect of metastasis formation promoted by increased metabolic activity raises the release of components from the osseous metabolism into the blood stream. These components are either enzymes directly involved in the alteration processes, metabolites/proteins that develop during this or bone matrix proteins released during this. These biomarkers are categorized in relation to their involvement in the bone formation or resorption as bone formation and resorption markers. Based on a PubMed literature search, a critical appraisal of the various biomarkers for diagnostic, prognostic, and monitoring purposes is given for patients with skeletal metastases caused by breast, prostate, lung, or renal cell carcinomas.

Adjuvant zoledronic acid in patients with early breast cancer: final efficacy analysis of the AZURE (BIG 01/04) randomised open-label phase 3 trial

BACKGROUND

The role of adjuvant bisphosphonates in early breast cancer is uncertain. We therefore did a large randomised trial to investigate the effect of the adjuvant use of zoledronic acid on disease-free survival (DFS) in high-risk patients with early breast cancer.

METHODS

In the AZURE trial, an open-label, international, multicentre, randomised, controlled, parallel-group phase 3 trial, women (age ≥18 years) with stage II or III breast cancer were randomly assigned (1:1) by a central automated 24-h computer-generated telephone minimisation system (balanced for number of involved axillary lymph nodes, tumour stage, oestrogen receptor status, type and timing of systemic therapy, menopausal status, statin use, and treatment centre) to receive standard adjuvant systemic treatment alone (control group) or with 4 mg intravenous zoledronic acid every 3-4 weeks for six doses, then every 3 months for eight doses, followed by every 6 months for five doses, for a total of 5 years of treatment. The primary endpoint was disease-free survival (DFS). Secondary endpoints were invasive DFS (IDFS), overall survival, time to bone metastases, time to distant recurrence, and subgroup analyses of variables included in the randomisation. All patients have completed study treatment. Results from the intention-to-treat final analysis of this fully recruited study are presented after a median follow-up of 84 months (IQR 66-93). This final efficacy analysis was planned to take place after 940 DFS events. This trial is registered with ClinicalTrials.gov, NCT00072020.

FINDINGS

3360 women were recruited from 174 centres in seven countries between Sept 4, 2003, and Feb 16, 2006. The number of DFS events did not differ between groups: 493 in the control group and 473 in the zoledronic acid group (adjusted hazard ratio [HR] 0·94, 95% CI 0·82-1·06; p=0·30). IDFS (HR 0·93, 95% CI 0·82-1·05; p=0·22), overall survival (0·93, 0·81-1·08; p=0·37), and distant recurrences (0·93, 0·81-1·07; p=0·29) were much the same in both groups. Zoledronic acid reduced the development of bone metastases, both as a first event (HR 0·78, 95% CI 0·63-0·96; p=0·020) and at any time during follow-up (0·81, 0·68-0·97; p=0·022). The effects of zoledronic acid on DFS were not affected by oestrogen-receptor status. However, zoledronic acid improved IDFS in those who were over 5 years since menopause at trial entry (n=1041; HR 0·77, 95% CI 0·63-0·96) but not in all other (premenopause, perimenopause, and unknown status) menopausal groups (n=2318; HR 1·03, 95% CI 0·89-1·20). 33 cases of suspected osteonecrosis of the jaw have been reported, with 26 confirmed on central review, all in the zoledronic acid group (1·7%, 95% CI 1·0-2·4).

INTERPRETATION

These results suggest no overall benefit from the addition of zoledronic acid to standard adjuvant treatments for early breast cancer. However, zoledronic acid does reduce the development of bone metastases and, for women with established menopause, improved disease outcomes.

FUNDING

Novartis Global and NIHR Cancer Research Network.

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.

Osteoporosis and cancer

Cancer is a major risk factor for bone loss and fractures. This is due both to direct effects of cancer cells on the skeleton and to deleterious effects of cancer-specific therapies on bone cells. Marked improvements in survival for many cancers mean that strategies to limit bone loss and reduce fracture risk must be incorporated into the care plans for nearly all patients with cancer. The vast majority of effort thus far has focused on bone loss in patients with breast and prostate cancers, with comparatively few studies in other malignancies. Antiresorptive therapies have proven nearly universally effective for limiting bone loss in cancer patients, although few studies have been powered sufficiently to include fractures as primary endpoints, and patients are frequently neither identified nor treated according to published guidelines. Nonpharmacologic approaches to limit falls, particularly in elderly patients, are also likely important adjunctive measures for most cancer patients.

Elevated serum P1NP predicts development of bone metastasis and survival in early-stage breast cancer

Bone is the most common site of metastasis of breast cancer, affecting most women with advanced disease. Procollagen type I N-terminal propeptide (P1NP), osteocalcin, CTX, and IL-6 are markers of bone turnover. Our objective was to determine whether serum levels of these proteins have clinical utility as predictors of breast cancer metastasis to bone. Blood was collected before treatment from 164 patients with stage I-III breast cancer from September 2001 to December 2008. Serum levels of P1NP, CTX, IL-6, and OC were measured using an automated immunoassay system. Correlations of the levels of these markers with time to bone metastasis development and with overall survival (OS) rate were assessed using Cox proportional hazards regression analysis and the Kaplan-Meier method. Fifty-five patients with stage I-III disease at the time of blood sample collection subsequently experienced metastasis to bone. A baseline P1NP level of at least 75 ng/mL predicted increased risk of bone metastasis (hazard ratio, 2.7 [95 % confidence interval, 1.2-6.0]; P = 0.031) and a poor OS rate (P = 0.031). Serum P1NP levels at or above 75 ng/mL correlate with a short time to development of bone metastasis and low overall survival in patients with stage I-III breast cancer.

Measurement of aminoterminal propeptide of type I procollagen (PINP) in serum

The aminoterminal propeptide of type I procollagen (PINP) in serum is a sensitive indicator of the synthesis of type I collagen. Four assays are available for PINP, two of them (intact PINP assays) measure the intact propeptide and the other two (total PINP assays) also detect a smaller antigen in serum. In many clinical situations, these assays give similar information, but renal insufficiency increases the concentration of the smaller antigen, influencing both the apparent concentration of PINP and assay calibration. Serum PINP is mostly affected by changes in bone metabolism. In infants and children, the concentration is much higher than in adults. Serum PINP (s-PINP) is a useful indicator of disease activity in Paget's disease of bone, in bone metastases of osteoblastic nature, and in the follow-up of treatment of osteoporosis. The IFCC and IOF recently recommended the use of s-PINP as a reference marker for bone formation in studies concerning fracture risk assessment and treatment response.

Seed, soil and secreted hormones: potential interactions of breast cancer cells with their endocrine/paracrine microenvironment and implications for treatment with bisphosphonates

The process of formation of metastasis is undoubtedly inefficient, with the majority of disseminated tumour cells perishing in their metastatic environment. Their ability to survive is determined by their intrinsic abilities, with emerging evidence of the importance of cancer stem cells possessing self propagating potential, but also the interaction with the premetastatic niche, which may either help or hinder their formation into micrometastasis, thus influencing recurrence and survival in breast cancer patients. Use of the bone targeted agents bisphosphonates in the adjuvant setting has been extensively studied in large clinical trials, and demonstrated an interesting interplay with the endocrine microenvironment, with postmenopausal women or premenopausal women receiving ovarian suppression therapy gaining a survival advantage compared to pre/perimenopausal women. The interaction between the endocrine hormones and the paracrine TGFβ growth factors may provide an explanation for the differences seen according to ovarian function in the response to bisphosphonates. In this review the evidence of interplay between ovarian endocrine hormones, TGFβ paracrine growth factors and bisphosphonates will be presented, and subsequent influence on breast cancer cells in the bone pre-metastatic niche hypothesised.

Bisphosphonates and other bone agents for breast cancer

BACKGROUND

Bone is the most common site of metastatic disease associated with breast cancer (BC). Bisphosphonates inhibit osteoclast-mediated bone resorption, and novel targeted therapies such as denosumab, inhibit key pathways in the vicious cycle of bone metastases.

OBJECTIVES

To assess the effect of bisphosphonates on skeletal-related events (SREs), bone pain, quality of life (QoL), recurrence and survival in women with breast cancer with bone metastases (BCBM), advanced breast cancer (ABC) without clinical evidence of bone metastases and early breast cancer (EBC).To assess the effect of denosumab on SREs, bone pain and (QoL) in women with (BCBM).

SEARCH METHODS

We searched the Specialised Register maintained by the Cochrane Breast Cancer Group (CBCGSR), MEDLINE, EMBASE and the WHO International Cancer Trials Registry Platform (WHO ICTRP) on 30 April 2011. We conducted additional handsearching of journals and proceedings of key meetings.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing: (a) bisphosphonates and control, or different bisphosphonates in women with BCBM; (b) denosumab and bisphosphonates in women with BCBM; (c) bisphosphonates and control in women with ABC; (d) bisphosphonates and control in women with EBC; and (e) early versus delayed bisphosphonate treatment in women with EBC.

DATA COLLECTION AND ANALYSIS

Two review authors (MW and NP) independently assessed the trials and extracted the data. We collected toxicity information from the trials.

MAIN RESULTS

We included thirty-four RCTs. In nine studies (2806 patients with BCBM), comparing bisphosphonates with placebo or no bisphosphonates, bisphosphonates reduced the SRE risk by 15% (risk ratio (RR) 0.85; 95% confidence interval (CI) 0.77 to 0.94; P = 0.001). This benefit was most certain with intravenous (i.v.) zoledronic acid (4 mg) (RR 0.59; 95% CI 0.42 to 0.82); i.v. pamidronate (90 mg) (RR 0.77; 95% CI 0.69 to 0.87); and i.v. ibandronate (RR 0.80; 95% CI 0.67 to 0.96). A direct comparison of i.v. zoledronic acid and i.v. pamidronate confirmed at least equivalent efficacy in a single large study. In three studies (3405 patients with BCBM), compared with bisphosphonates, subcutaneous (s.c.) denosumab was more effective in reducing the risk of SREs (RR 0.78; 95% CI 0.72 to 0.85; P < 0.00001).Bisphosphonates reduced the SRE rate in 12 studies (median reduction 28%, range 14% to 48%), with statistically significant reductions reported in 10 studies. Women with BCBM treated with bisphosphonates showed significant delays in the median time to SREs. Compared with placebo or no bisphosphonates, treatment with bisphosphonates significantly improved bone pain in six out of eleven studies. Improvements in global QoL with bisphosphonates compared to placebo were reported in two out of five studies (both ibandronate studies). Treatment with bisphosphonates did not appear to affect survival in women with BCBM. Compared to i.v. zoledronic acid, denosumab also significantly reduced the SRE rate, delayed the time to SREs and prolonged the time in developing pain for patients with no or mild pain at baseline; but there was no difference in survival between patients treated with denosumab and zoledronic acid.Bisphosphonates in women with ABC without clinically evident bone metastases did not reduce the incidence of bone metastases, or improve survival in three studies (320 patients).In seven studies (7847 patients with EBC), currently there is no evidence supporting bisphosphonates in reducing the incidence of bone metastases compared to no bisphosphonates (RR 0.94; 95% CI 0.82 to 1.07; P = 0.36). In three studies (2190 patients with EBC), early bisphosphonate treatment also did not significantly reduce the incidence of bone metastases compared to delayed bisphosphonate treatment (RR 0.73; 95% CI 0.40 to 1.33; P = 0.31). Currently, there is insufficient evidence to make a conclusion about the role of adjuvant bisphosphonates in reducing visceral metastases, locoregional recurrence and total recurrence, or improving survival. There was strong heterogeneity in EBC studies examining the outcomes of total recurrence and survival.Reported toxicity was generally mild. Renal toxicity and osteonecrosis of the jaw (ONJ) have been identified as potential problems with bisphosphonate use. ONJ was reported at similar rates for patients on denosumab compared to zoledronic acid. This highlighted a need for maintaining good oral care, prior to and during treatment, for patients who received long-term bone agents.

AUTHORS' CONCLUSIONS

In women with clinically evident BCBM, bisphosphonates (oral and i.v.) and denosumab (s.c.) reduced the risk of developing SREs, as well as delaying the time to SREs. Some bisphosphonates may also reduce bone pain and may improve QoL. The optimal timing and duration of treatment for patients with BCBM remains uncertain. There is currently insufficient evidence to support the routine use of bisphosphonates as adjuvant treatment for patients with EBC. However, a number of large clinical trials investigating bisphosphonates in EBC have completed accrual and are awaiting results.

Diagnostic and prognostic use of bone turnover markers

The use of bone turnover markers in oncology includes monitoring of anticancer treatment in patients with malignant disease metastatic to the bones (therapeutic monitoring), predicting the risk of bone relapse in patients with a first diagnosis of potentially curative, early-stage malignant tumors (prognostic use), and making an early diagnosis of (microscopic) malignant bone disease in patients with a known malignant tumor to start early bone-targeted treatment and avoid skeletal-related events (diagnostic use). Concerning prognostic use, there is limited evidence for bone turnover markers to predict the occurrence of metachronous bone metastases in patients with early-stage malignant tumors, with serum PINP (N-terminal propeptide of procollagen type 1), ICTP (Carboxyterminal cross-linked telopeptide of type I collagen), bone sialoprotein (BSP), and tumor immunoexpression of BSP being the most promising candidates. Concerning diagnostic use, serum bone-specific alkaline phosphatise (BSAP), PINP and osteoprotegerin (OPG) were repeatedly shown to be associated with synchronous bone metastases in patients with breast or lung cancer, but sensitivity of these markers was too low to suggest that they might be preferred over conventional bone scans for the diagnosis of bone metastases. A somewhat higher sensitivity for the diagnosis of bone metastases was found for urinary NTx (N-terminal cross-linked telopeptide of type I collagen) and serum ICTP in solid tumor patients, serum TRAcP-5b (Tartrate-resistant acid phosphatase type 5b) in patients with breast cancer and serum BSAP, PINP and OPG in prostate cancer patients. Both prognostic and diagnostic use of bone turnover markers are reviewed in this chapter.

Consensus on the utility of bone markers in the malignant bone disease setting

Biochemical markers of bone turnover provide insight into ongoing rates of skeletal metabolism and tumor-bone interactions in patients with malignant bone disease. This article reviews the available recent evidence assessing the potential of bone markers for detecting and monitoring malignant bone lesions in patients with advanced cancers, and for assessing overall skeletal health and response to antiresorptive therapies in patients at all stages of cancer progression. Most data thus far are for urinary N-terminal cross-linked telopeptide of type I collagen (NTX) in predicting risks of skeletal morbidity and death and monitoring response to zoledronic acid in patients with bone metastases. Ongoing studies are evaluating such correlations for other markers and therapies. Emerging evidence suggests that bone markers may help identify patients at high risk for bone metastasis or bone lesion progression, thereby allowing improved follow-up. Results from ongoing clinical trials evaluating such potential applications of bone markers are awaited.

Bisphosphonates in oncology

Bone metastases result in considerable morbidity, often affecting quality of life and independence over years, and may place complex demands on health care resources. The bisphosphonates have been shown to reduce skeletal morbidity in multiple myeloma and solid tumours affecting bone by 30-50%. Quite appropriately, these agents are increasingly used alongside anticancer treatments to prevent skeletal complications and relieve bone pain. The use of bisphosphonates in early cancer has become increasingly important to prevent adverse effects of cancer treatments on bone health. These include chemotherapy induced ovarian failure and the use of aromatase inhibitors in breast cancer and androgen deprivation therapy in prostate cancer. Bisphosphonate strategies, similar to those used to treat post-menopausal osteoporosis, are the intervention of choice for patients with low bone mineral density or rapid bone loss, along with adequate calcium and vitamin D intake and a healthy lifestyle. There is a strong preclinical rationale for bisphosphonates to prevent metastasis, primarily through inhibition of the vicious cycle of metastasis within the microenvironment. Recent data suggest that adjuvant bisphosphonates, at least in some patient subgroups, may modify the course of the disease and disrupt the metastatic process, reducing the risks of disease recurrence. In comparison to most other cancer treatments, adverse events related to bisphosphonate therapy are generally mild and infrequent; thus, the benefits of treatment within licensed indications will almost always outweigh the risks.

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.

Effects of continuous combined hormone replacement therapy and clodronate on bone mineral density in osteoporotic postmenopausal women: a 5-year follow-up

OBJECTIVE

To determine the effects of HRT with or without clodronate on bone mineral density (BMD) change and bone turnover markers.

DESIGN

Prospective, partly randomized trial.

SETTING

Kuopio University Hospital, Finland.

POPULATION

167 osteoporotic women (61+/-2.7 years; T-score<or=-2.5 SD).

METHODS

Estradiol 2 mg+NETA 1 mg, randomization to additional 800 mg clodronate (n=55, HT+C-group) or placebo (n=55, HT-group); if contraindications to HRT, clodronate (n=57, C-group).

MAIN OUTCOME MEASURES

BMD by DXA after 1, 3 and 5 years, serum osteocalcin (OC) and bone-specific alkaline phosphatase (BAP) at the baseline and after 3 years.

RESULTS

After 5 years, adjusted lumbar BMD increased by 4.2% in the HT-group and 3.7% in the HT+C-group. The C-group showed a decrease of -1.1%, the total difference being 5.3% and 4.8% between HT, HT+C vs. C-group, respectively (p<0.001). In the femoral neck, the adjusted 5-year BMD benefit was 1.3% and 2.4% in the HT- and HT+C-groups, respectively, the net loss of BMD in the C-group was -3.3% (p<0.05 between HT+C vs. C). By 3 years, OC decreased by 55.0%, 70.3% and 53.8% in the HT-, HT+C- and C-groups, respectively (p<0.001 vs. baseline). The significant decreases of BAP were 39.4% in the HT-group, 42.1% in the HT+C-group and 30.2% in the C-group with no significant differences between the groups after adjustments.

CONCLUSIONS

In postmenopausal women with osteoporosis, HRT increased spinal and femoral BMD, but the combination of HRT and clodronate did not offer an extra gain of bone mass.