Too Much, Too Little, Too Late to Start Again? Assessing the Efficacy of Bisphosphonates in Patients with Bone Metastases from Breast Cancer

Extracting microtentacle dynamics of tumor cells in a non-adherent environment

During metastasis, tumor cells dynamically change their cytoskeleton to traverse through a variety of non-adherent microenvironments, including the vasculature or lymphatics. Due to the challenges of imaging drift in non-adhered tumor cells, the dynamic cytoskeletal phenotypes are poorly understood. We present a new approach to analyze the dynamic cytoskeletal phenotypes of non-adhered cells that support microtentacles (McTNs), which are cell surface projections implicated in metastatic reattachment. Combining a recently-developed cell tethering method with a novel image analysis framework allowed McTN attribute extraction. Full cell outlines, number of McTNs, and distance of McTN tips from the cell body boundary were calculated by integrating a rotating anisotropic filtering method for identifying thin features with retinal segmentation and active contour algorithms. Tethered cells behave like free-floating cells; however tethering reduces cell drift and improves the accuracy of McTN measurements. Tethering cells does not significantly alter McTN number, but rather allows better visualization of existing McTNs. In drug treatment experiments, stabilizing tubulin with paclitaxel significantly increases McTN length, while destabilizing tubulin with colchicine significantly decreases McTN length. Finally, we quantify McTN dynamics by computing the time delay autocorrelations of 2 composite phenotype metrics (cumulative McTN tip distance, cell perimeter:cell body ratio). Our automated analysis demonstrates that treatment with paclitaxel increases total McTN amount and colchicine reduces total McTN amount, while paclitaxel also reduces McTN dynamics. This analysis method enables rapid quantitative measurement of tumor cell drug responses within non-adherent microenvironments, using the small numbers of tumor cells that would be available from patient samples.

AAPT Diagnostic Criteria for Chronic Cancer Pain Conditions

Chronic cancer pain is a serious complication of malignancy or its treatment. Currently, no comprehensive, universally accepted cancer pain classification system exists. Clarity in classification of common cancer pain syndromes would improve clinical assessment and management. Moreover, an evidence-based taxonomy would enhance cancer pain research efforts by providing consistent diagnostic criteria, ensuring comparability across clinical trials. As part of a collaborative effort between the Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) and the American Pain Society (APS), the ACTTION-APS Pain Taxonomy initiative worked to develop the characteristics of an optimal diagnostic system. After the establishment of these characteristics, a working group consisting of clinicians and clinical and basic scientists with expertise in cancer and cancer-related pain was convened to generate core diagnostic criteria for an illustrative sample of 3 chronic pain syndromes associated with cancer (ie, bone pain and pancreatic cancer pain as models of pain related to a tumor) or its treatment (ie, chemotherapy-induced peripheral neuropathy). A systematic review and synthesis was conducted to provide evidence for the dimensions that comprise this cancer pain taxonomy. Future efforts will subject these diagnostic categories and criteria to systematic empirical evaluation of their feasibility, reliability, and validity and extension to other cancer-related pain syndromes.

PERSPECTIVE

The ACTTION-APS chronic cancer pain taxonomy provides an evidence-based classification for 3 prevalent syndromes, namely malignant bone pain, pancreatic cancer pain, and chemotherapy-induced peripheral neuropathy. This taxonomy provides consistent diagnostic criteria, common features, comorbidities, consequences, and putative mechanisms for these potentially serious cancer pain conditions that can be extended and applied with other cancer-related pain syndromes.

In vitro and in vivo effects of photodynamic therapy on metastatic breast cancer cells pre-treated with zoledronic acid

BACKGROUND

Photodynamic therapy (PDT), a non-ionizing, minimally invasive drug-light treatment, has recently been shown to successfully ablate tumor within rat vertebrae with concurrent improvements in bone strength and architecture. The bisphosphonate zoledronic acid (zol), a current drug for patients with skeletal metastases, primarily works by inhibiting osteoclast activity, but direct anti-tumor effects have also been reported. However, it is unknown if or how pre-treatment with zol may alter the tumorcidal effect of PDT. The aim of this study was to evaluate the effect of PDT, both in vitro and in vivo, on zol-pretreated cancer cells.

MATERIALS AND METHODS

Human metastatic breast cancer cells (MT-1) were cultured in vitro and treated with zol (10μM) for 24h, followed by PDT treatment. Cell viability was assessed by fluorescence microscopy and flow cytometry. In vivo, MT-1 cells were injected (intracardiac) into athymic rats. On day 7, zol (60μg/kg) was administered subcutaneously. On day 14, PDT was applied (1mg/kg verteporfin; 75J; 690nm) to lumbar vertebrae. Histomorphometric assessment of tumor burden was evaluated on day 21.

RESULTS

The cell viability measured in vitro after PDT treatment decreased in cells pre-incubated with zol up to 20% compared to treatment with PDT alone. Zol alone had no influence on the MT-1 cell viability. In vivo, all treatments, either alone or combined, had a tumorcidal effect.

CONCLUSIONS

Pre-treatment with zol in vivo did not yield a synergistic effect on tumor ablation in contrast to the in vitro results, but neither did it abrogate the positive tumorcidal effect of PDT, so that those therapies may be applied in combination.

Health state utilities for skeletal-related events secondary to bone metastases

INTRODUCTION

Patients with bone metastases often experience skeletal-related events (SREs). Although cost-utility models are used to examine treatments for metastatic cancer, limited information is available on utilities of SREs. The purpose of this study was to estimate the disutility of four SREs: spinal cord compression, pathological fracture, radiation to bone, and surgery performed to stabilize a bone.

METHODS

General population participants from the UK and Canada completed time trade-off (TTO) interviews to assess the utility of health states drafted based on literature review, clinician interviews, and patient interviews. Respondents first rated a health state describing cancer with bone metastases. Then, the SREs were added to this health state.

RESULTS

Interviews were completed with 187 participants (50.8 % male, 80.2 % white). Cancer with bone metastases without an SRE had a mean utility of 0.47 (SD = 0.43) on a standard utility scale (1 = full health, 0 = death). Of the SREs, spinal cord compression was associated with the greatest disutility (i.e., the utility decrease): -0.32 with paralysis and -0.22 without paralysis. Surgery had a disutility of -0.07. Leg, arm, and rib fractures had disutilities of -0.06, -0.04, and -0.03. Two weeks of daily radiation treatment had a disutility of -0.06, while two radiation appointments had the smallest impact on utility (-0.02).

CONCLUSION

All SREs were associated with statistically significant utility decreases, suggesting a perceived impact on quality of life beyond the impact of cancer with bone metastases. The resulting disutilities may be used in cost-utility models examining treatments to prevent SREs secondary to bone metastases.

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.

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.

Radiotherapeutic Options for Symptom Control in Breast Cancer

SUMMARY: The majority of breast cancer patients will require radiation therapy at some time during the course of their disease. An estimated 30-50% of all radiation treatments are of palliative nature, either to alleviate symptoms or prophylactic to prevent deterioration of quality of life due to locally progressive disease. Radiotherapy is a locally effective tool, and typically causes no systemic and mostly mild acute side effects. The following article provides an overview of options and decision-making in palliative radiotherapy for symptom control.

Serum C-telopeptide levels predict the incidence of skeletal-related events in cancer patients with secondary bone metastases

INTRODUCTION

We evaluated serum C-telopeptides (CTX) to see whether they may be useful as predictive markers for disease progression in cancer patients with bone metastases who are being treated with zoledronic acid (ZA).

PATIENTS AND METHODS

This was a prospective, nonrandomised study in which 26 patients with solid tumours and confirmed bone metastases were treated with ZA (4 mg every 3-4 weeks) for 24 months or until a skeletal-related event (SRE) was observed. Serum CTX levels were determined at baseline and 6, 12, 18 and 24 months after study initiation. SRE were evaluated using bone scintigraphy.

RESULTS

Study participants had prostate (50%), breast (31%), lung (11%) or bladder (8%) tumours. Mean age was 69 (range 52-84) years, and 65% men. At baseline, overall mean CTX levels were 562.47 ± 305.17 pg/dl. Patients who showed disease progression during the study period showed significantly higher CTX levels at baseline and after 18 months of ZA treatment than patients who did not progress (p = 0.040 and p = 0.006, respectively). Patients with ≥ 5 bone metastases at diagnosis had significantly higher CTX levels after 18 months of ZA treatment than patients with < 5 bone metastasis (p = 0.001). Similarly, at 12 and 18 months, patients without SRE had significantly lower CTX levels than patients in whom a SRE was observed (p = 0.005 and p = 0.001, respectively).

CONCLUSIONS

Changes in serum CTX levels seem to predict the potential for tumour control and the likelihood of developing an SRE in a sample of patients with solid tumours and bone metastases treated with ZA.

Anabolic and antiresorptive drugs improve trabecular microarchitecture and reduce fracture risk following radiation therapy

Many patients with symptomatic bone metastases receive radiation therapy, even though radiation is known to have potential adverse effects on bone. We hypothesized that the concurrent use of a bisphosphonate drug (zoledronic acid, ZA) or a combination of ZA plus an anabolic agent (parathyroid hormone, PTH) would lead to improvements in the microarchitecture and mechanical properties of irradiated bone. Human breast cancer cells were injected into the distal femur of 56 female nude mice, which were then divided into four groups: no treatment (0 Gy), radiation administered 4 weeks postinjection (20 Gy), radiation plus ZA (12.5 microg/kg weekly from weeks 4 to 12) (20 Gy + ZA), and radiation followed by ZA (25 microg/kg weekly from weeks 4 to 8) and PTH(1-34) (100 microg microg/kg daily from weeks 8 to 12) (20 Gy + ZA + PTH). Left limbs served as normal control bones. Bone loss over the 12-week study was tracked with serial radiography and bone densitometry. At the end of the study, micro-computed tomography and mechanical testing were used to quantify bone microarchitecture and bone strength. Radiation alone failed to prevent tumor-induced decreases in bone mineral density (BMD), trabecular bone volume, and bone strength. Treatment with 20 Gy + ZA or 20 Gy + ZA + PTH as adjuncts to radiation was effective at preserving trabecular bone architecture and bone strength at normal levels. ZA reduced the risk of mechanical fragility following irradiation of a lytic bone lesion. Supplemental use of PTH did not result in further increases in bone strength but was associated with significant increases in BMD and bone mass, suggesting that it may be beneficial in enhancing bone architecture following radiation therapy.

Skeletal-related events (SREs) in breast cancer patients with bone metastases treated in the nontrial setting

BACKGROUND

Clinical trials exploring bisphosphonate (BP) use in patients with bone metastases from breast cancer (BC) consistently state skeletal-related event (SRE) rates >50%. These trials predominantly include patients with bone only disease, and also frequently use screening radiology to detect asymptomatic fractures. Both these variables are likely to increase the incidence of SREs and thereby overestimate BP benefit. Little data exists regarding the natural history of SREs among patients treated with i.v. BPs in the nontrial setting.

MATERIALS AND METHODS

Charts from two institutions (PMH and CVH) were reviewed to determine predictive risk factors for SRE development post i.v. pamidronate therapy in BC patients with bone metastases.

RESULTS

Eighty-seven charts from 1999 to 2005 with complete outcome data were identified and reviewed. Pain was the most common presentation for bone metastases occurring in 49 women (56%). At diagnosis, 31 patients (35%) had bone only disease, and 57 (65%) had concomitant visceral metastases. Twenty-nine patients (33%) experienced an SRE prior to commencing BP treatment. Thirty-three women (38%) subsequently developed an SRE after a median of 5 BP treatments. SREs included radiation (79%), pathologic fractures (12%), and hypercalcemia (9%). On Cox regression, baseline history of osteoporosis (HR = 2.8; p = 0.045) and the presence of bone only disease (HR 3.0; p = 0.003) were predictive of SRE development. In patients with and without osteoporosis, median time to SRE was 305 and 866 days, respectively (p < 0.001).

CONCLUSION

The frequency of SREs in this study was significantly lower than that reported in clinical trials of i.v. BP use. The lower incidence of SREs in this setting could affect sample size calculations for future event-driven BP trials. While the greatest risk of SREs despite BP therapy appears to be in patients with osteoporosis and with metastatic disease confined to the skeleton, further prospective study is merited to confirm and characterize the impact of these risk factors on SRE development.

Defining the therapeutic window of vertebral photodynamic therapy in a murine pre-clinical model of breast cancer metastasis using the photosensitizer BPD-MA (Verteporfin)

Breast cancer is known to cause metastatic lesions in the bone, which can lead to skeletal-related events. Currently, radiation therapy and surgery are the treatment of choice, but the success rate varies and additional adjuncts are desirable. Photodynamic therapy (PDT) has been applied successfully as a non-radiative treatment for numerous cancers. Earlier work has shown that the athymic rat model is suitable to investigate the effect of PDT on bone metastasis and benzoporphyrin-derivative monoacid ring A (BPD-MA; verteporfin) has been shown to be a selective photosensitizer. The aim of this study was to define the therapeutic window of photosensitizer with regard to drug and light dose. Human breast carcinoma cells (MT-1)-stable transfected with the luciferase gene-were injected intra-cardiacally into athymic rats. At 14 days, the largest vertebral lesion by bioluminescence imaging was targeted for single treatment PDT. A drug escalating-de-escalating scheme was used (starting drug dose and light energy of 0.2 mg/kg and 50 J, respectively). Outcomes included 48 h post-treatment bioluminescence of remaining viable tumour, histomorphometric assessment of tumour burden, and neurologic evaluation. The region of effect by bioluminescence and histology increased with increasing drug dose and light energy. A safe and effective drug-light dose combination in this model appears to be 0.5 mg/kg BPD-MA and applied light energy of less than 50 J for the thoracic spine and 1.0 mg/kg and 75 J for the lumbar spine. For translation to clinical use, it is an advantage that BPD-MA (verteporfin), a second-generation photosensitizer, is already approved to treat age-related macular degeneration. Overall, PDT represents an exciting potential new minimally-invasive local, safe and effective therapy in the management of patients with spinal metastases.

Pharmacotherapy of bone metastases in breast cancer patients

A diagnosis of bone metastases is often a devastating occurrence in breast cancer patients. Bone metastases are associated with increased morbidity as reflected through pain, reduced quality of life and skeletal-related events. This paper reviews the role of different pharmacotherapeutic agents in the treatment of bone metastases from breast cancer. Randomised controlled trials of osteoclast-inhibiting agents, that is the bisphosphonates, have shown significant patient benefit. The aims of bisphosphonates are to prevent and delay skeletal-related events, reduce bone pain and improve quality of life. However, there are some limitations with bisphosphonate treatment. Biochemical markers of bone turnover seem to be a promising tool in guiding bisphosphonate treatment and future research directions. Hopefully, patient management will be further improved as new agents become available such as denosumab, osteoprotegerin analogues and anti-angiogenic agents.

Evaluating distant metastases in breast cancer: from biology to outcomes

There is an urgent need to understand distant metastases in breast cancer as they are the most lethal form of recurrence and a major cause of mortality in patients. Some predictors for distant metastases, including nodal status, tumor grade, and hormonal status, are useful in identifying patients at increased risk for distant metastases. Adjuvant endocrine therapy has been the treatment of choice for postmenopausal women with hormone-sensitive breast cancer, and some therapies have shown significant reductions in the risk of distant metastases. Skeletal metastases in breast cancer are treated with bisphosphonates with a certain level of success. With more new agents undergoing clinical trials, a thorough review of the specific and long-term safety of these agents is essential, as is a better understanding of the deterioration in the quality of life and cost concerns of patients who develop distant metastases. Gene-expression profiling is a new entrant in the field of distant metastases diagnosis, which is largely successful in defining gene signatures that predict the development of distant metastases. This review will discuss the biology and the impact of distant metastases on outcomes for patients with breast cancer; it also encompasses the current status, emerging focus, and future perspectives in treatment of skeletal metastases in patients with breast cancer.

Metastatic breast cancer induces an osteoblast inflammatory response

Breast cancer preferentially metastasizes to the skeleton, a hospitable environment that attracts and allows breast cancer cells to thrive. Growth factors released as bone is degraded support tumor cell growth, and establish a cycle favoring continued bone degradation. While the osteoclasts are the direct effectors of bone degradation, we found that osteoblasts also contribute to bone loss. Osteoblasts are more than intermediaries between tumor cells and osteoclasts. We have presented evidence that osteoblasts contribute through loss of function induced by metastatic breast cancer cells. Metastatic breast cancer cells suppress osteoblast differentiation, alter morphology, and increase apoptosis. In this study we show that osteoblasts undergo an inflammatory stress response in the presence of human metastatic breast cancer cells. When conditioned medium from cancer cells was added to human osteoblasts, the osteoblasts were induced to express increased levels of IL-6, IL-8, and MCP-1; cytokines known to attract, differentiate, and activate osteoclasts. Similar findings were seen with murine osteoblasts and primary murine calvarial osteoblasts. Osteoblasts are co-opted into creating a microenvironment that exacerbates bone loss and are prevented from producing matrix proteins for mineralization. This is the first study implicating osteoblast produced IL-6, IL-8 (human; MIP-2 and KC mouse), and MCP-1 as key mediators in the osteoblast response to metastatic breast cancer cells.

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

BACKGROUND

Phase III study comparing the effect of oral ibandronate and intravenous zoledronic acid on bone markers.

PATIENTS AND METHODS

Breast cancer patients with bone metastases received ibandronate 50 mg/day (n = 137) or zoledronic acid 4 mg every 4 weeks (n = 138) for 12 weeks. The primary end point was mean percentage change in serum levels of cross-linked C-terminal telopeptide of type I collagen (S-CTX) at week 12. Urinary CTX (U-CTX), bone alkaline phosphatase (ALP), amino-terminal procollagen propeptide of type I collagen (PINP) and osteocalcin (OC) were also measured and bone pain and safety assessed.

RESULTS

Both bisphosphonates significantly reduced S-CTX (mean ibandronate 76% +/- 29 (SD) versus mean zoledronic acid 73% +/- 47; P < 0.001 for both versus baseline) and U-CTX (ibandronate 78% +/- 50 versus zoledronic acid 86% +/- 17; P < 0.001). The difference in S-CTX between treatments was 0.6% (confidence interval -1.7% to 3.0%), which was within the prespecified noninferiority margin. Bone ALP, PINP and OC decreased by 26%-47% compared with baseline with both bisphosphonates. Compared with zoledronic acid, ibandronate patients reported fewer adverse events overall (65.0% versus 75.9%), and on days 1-3 (8.0% versus 47.5%), including less pyrexia (overall incidence 0% versus 16.8%) and bone pain (5.8% versus 12.4%).

CONCLUSIONS

Oral ibandronate was well tolerated and statistically noninferior to zoledronic acid for percentage change in the bone resorption marker, S-CTX.

An audit to determine the time taken to administer intravenous bisphosphonate infusions in patients diagnosed with metastatic breast cancer to bone in a hospital setting

OBJECTIVE

Bone metastases can occur in many forms of cancer. More than two-thirds of women with metastatic breast cancer may be affected by bone metastasis during the course of their disease. Bisphosphonates, which inhibit osteoclast-mediated bone resorption, are an established standard of care for patients with bone metastases. For patients with cancer and bone metastases, bisphosphonates are associated with a significant reduction in skeletal-related events such as vertebral fractures, non-vertebral fractures as well as increasing the time to skeletal event. The purpose of this study was to quantify the current time involved in the administration of i.v. bisphosphonates and how this might impact on patient experience and cancer unit capacity.

RESEARCH DESIGN AND METHODS

A pilot audit was initially conducted at the Royal Marsden Hospital (RMH), London (both Chelsea and Sutton sites), and was followed by audits at a further two UK hospital sites: Velindre Hospital, Cardiff and the Royal Surrey County Hospital, Guildford. The study was conducted between December 2005 and September 2006.

RESULTS

Overall, 151 forms were completed. Of the total patients audited, approximately 71% had a diagnosis of breast cancer. Where data on the reason for attendance were collected (Velindre and the Royal Surrey County Hospital), over 77% of patients attended hospital for the sole reason of having an i.v. bisphosphonate administered. The majority of patients (94%) required cannulation prior to infusion and, at the sites where this information was recorded (Royal Surrey County Hospital and Velindre Hospital), almost one-third of patients required two or more attempts before they were successfully cannulated. The time that the patients spent on the unit where the i.v. bisphosphonates were administered was greater for patients receiving pamidronate compared to those receiving zoledronic acid (2 h 36 min and 1 h 38 min, respectively). The magnitude of the difference was not as great as would be expected considering zoledronic acid should take one-sixth of the time to administer (Royal Marsden Hospital, pamidronate 1 h 29 min, zoledronic acid 18 min: Royal Surrey County Hospital, zoledronic acid 21 min: Velindre Hospital, pamidronate 1 h 42 min, zoledronic acid 17 min).

CONCLUSIONS

I.v. bisphosphonates are accepted as standard clinical practice for the management of metastatic bone disease. They are often prescribed for long periods of time, so tolerability and patient acceptability are important factors in therapy. The administration of i.v. bisphosphonates contributes a substantial time burden for patients travelling to the hospital, considering that in most cases the purpose is for this treatment only. It also places a significant burden on hospital resources, creating capacity planning challenges. Receiving an i.v. bisphosphonate also has other disadvantages associated with it, such as the need for patients to undergo repeated cannulation. Service redesign, such as home administration of i.v. bisphosphonates, could help to overcome issues highlighted in this audit. The use of oral alternatives to pamidronate and zoledronic acid which may be more convenient for patients, and perhaps also cost-effective, should also be of ongoing interest.

The use of bisphosphonates in elderly cancer patients

As life expectancy increases throughout the 21st century, the size of the elderly population will also expand. This will have a marked effect on the number of patients with cancer who are classified as elderly. Despite this, the design of most clinical studies of cancer therapies excludes those patients who are > or =70 years of age. Bisphosphonates are an example of a cancer therapy that has not been examined in randomized clinical trials of elderly patients. These agents are used for the prevention of skeletal complications and the relief of bone pain in patients with bone metastases. When deciding which bisphosphonate to prescribe to an elderly patient, each drug should be considered on its individual merits. Examples of areas of concern with bisphosphonates in elderly patients include their relative renal safety profiles and propensity for osteonecrosis of the jaw. Another consideration when choosing the most appropriate formulation is the preferred method of administration (oral or i.v.), which may affect patient compliance with therapy. As the use of bisphosphonates increases, the need for data on their use in elderly patients also becomes greater. Clinical trials of bisphosphonates in this patient population are currently under way, and their results are keenly awaited.