Antiresorptive treatment options and bone health in cancer patients—safety profiles and clinical considerations

Denosumab vs. zoledronic acid treatment in post-menopausal breast cancer: a 2-year prospective observational study

Adjuvant treatment for post-menopausal women with early breast cancer (BC) includes aromatase inhibitors (AI), known to decrease bone mineral density (BMD). In this study, we investigate whether denosumab is a valid second option for patients unable to receive standard adjuvant i.v. zoledronic acid (ZA). In total, 212 patients have been evaluated after they did not receive ZA. Of those 194 were included. After evaluation by an endocrinologist, all patients were offered ZA as their first choice and 15% accepted (N = 29). The remaining 85% were offered denosumab (N = 165). All patients were followed prospectively with blood tests up to 24 months. DXA scans were performed at baseline and 24 months. No difference was observed between the two treatment groups at baseline, with regard to anthropometry and standard biochemistry. Markers of bone turnover (p-PINP, p-CTX, p-bone-specific alkaline phosphatase and p-osteocalcin) all showed significant suppression compared to baseline and remained suppressed throughout the 2 years. BMD showed small and significant increases at the spine (0.024 g/cm²) and total hip (0.019 g/cm²) in the denosumab group but no change at the femoral neck(-0.011g/cm²). In the ZA group, we observed no significant change at the spine (0.015 g/cm²) and total hip (-0.001g/cm²) and a small significant decrease at the femoral neck (-0.037 g/cm²). However, when we compared BMD change between the treatment groups, we found no significant difference.Conclusions: Our data indicate that for BC patients in AI treatment who refused or were not able to receive ZA treatment, denosumab might be recommended as a second choice. Regarding markers of bone turnover and BMD denosumab is equal to ZA.Summary: Women with early breast cancer receiving anti-estrogen treatment are at risk of developing osteoporosis.We followed 194 women receiving zoledronic acid (ZA) or denosumab for up to 2 years.We find that with regard to bone protection, denosumab is a viable alternative to ZA and might be recommended as a second choice.

Thermal ablation to relieve pain from metastatic bone disease: a systematic review

OBJECTIVE

To review the efficacy of percutaneous thermal ablation (TA) of bone metastases (radiofrequency ablation [RFA], microwave ablation [MWA], cryoablation [CA], and MR-guided focused ultrasound [MRgFUS]) in reducing pain in patients with advanced stage cancer.

MATERIALS AND METHODS

We searched MEDLINE/PubMed, MEDLINE In-Process, BIDS ISI, Embase, CINAHL, and the Cochrane database using the keywords "ablation," "painful," "bone," and "metastases" combined in multiple algorithms. Inclusion criteria were: original clinical studies published between 2001 and 2018; performance of RFA, MWA, CA or MRgFUS; and quantitative pain assessment before/after TA of bone metastasis.

RESULTS

Eleven papers (3 on RFA, 1 on MWA, 2 on CA, and 5 on MRgFUS) involving 364 patients were reviewed. A technical success rate of 96-100% was reported, with follow-up for up to 6 months. At baseline, pain scores ranged from 5.4 to 8, at 1-4 weeks from 0.5 to 5, and at 12 weeks from 0.3 to 4.5. Mean pain reduction compared with baseline ranged from 26 to 91% at 4 weeks and from 16% to 95% at 12 weeks. MWA treatments caused no complications, whereas MRgFUS showed the highest complication rate. The number of minor complications observed ranged from 0 to 59 (complication ratio 0-1.17), whereas the number of significant adverse effects ranged from 0 to 4 (complication ratio 0-0.04).

CONCLUSION

All techniques achieved pain relief after 1 and 3 months, in up to 91% and 95% of patients respectively. MWA showed a negligible complication rate, whereas MRgFUS is associated with a noteworthy rate of adverse events. Future studies should adopt a standardized pain reporting scale to allow for meta-analysis.

Bisphosphonate use and the risk of breast cancer: a meta-analysis of observational studies

PURPOSE

To summarize current evidence of the association of bisphosphonate use with breast cancer risk, we used a systematic review and meta-analysis of observational studies to explore this issue.

METHODS

A comprehensive search was conducted on PubMed, EMBASE, and the Cochrane Library. Pooled relative risk (RR) estimates and 95% confidence intervals (CIs) were calculated using the random effects model.

RESULTS

Bisphosphonate use was associated with a 16% lower breast cancer risk (pool RR0.84, 95%CI 0.77-0.90, n = 8). A protective effect of bisphosphonate was found in cohort studies (RR 0.85, 95%CI 0.80-0.90, n = 4) and case-control studies (RR 0.78, 95%CI 0.64-0.96, n = 4).We also found that the use of bisphosphonate resulted in a statistically significant reduction in all breast cancer risk (RR 0.87, 95%CI 0.81-0.93) and greater reduction in invasive breast cancer risk (RR 0.78, 95%CI 0.68-0.91) and contralateral breast cancer risk (RR, 0.41; 95% CI, 0.20-0.84).With respect to the type of bisphosphonate, we found that alendronate and etidronate resulted significant reduction in breast cancer risk. The short-term use of bisphosphonate (<1 y) led to nonsignificant change (RR 0.93, 95%CI 0.86-1.00), but a significant 26% reduction of breast cancer risk was noted with long-term use (>1 y) (RR 0.74, 95%CI 0.66-0.83).

CONCLUSIONS

Our results supported bisphosphonate as being effective in preventing breast cancer, including invasive and contralateral breast cancer. Furthermore, the long-term use (>1 y) of bisphosphonate was more significant in lowering breast cancer risk.

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 .

Age-related differences in persistence with bisphosphonates in women with metastatic breast cancer

Aims

To investigate age-related persistence with bisphosphonates (BIS) in women with breast cancer (BC) and bone metastases.

Methods

We included a dataset of 1541 patients diagnosed with BC and bone metastases and initially treated with BIS between 1994 and 2013. The primary outcome measure was the age-related rate of BIS discontinuation within 12 months after treatment initiation. Therapy discontinuation was defined as a period of at least 90 days without treatment. A multivariate Cox regression model was created to determine the influence of age on the risk of discontinuation. Health insurance coverage (private/statutory), type of care (gynecological/general), region (West/East Germany), depression, chemotherapy, hormone therapy, pain medication, antidepressants, and the number of co-medications were included as covariates.

Results

The mean ages in the group of women <70 and that of women ≥70 years of age were 55.7 (SD: 9.8) and 76.7 (SD: 5.1) years respectively. Within 12 months after treatment initiation, 44.3% of women <70 and 34.8% of women ≥70 had terminated treatment (p-value<0.001). Patients aged ≥70 were at a lower risk of treatment discontinuation than patients <70 (HR=0.78, 95% CI: 0.67–0.91). Furthermore, treatment in gynecological practices, chemotherapy, hormone therapy, pain medication, and number of co-medications decreased the risk of discontinuation. By contrast, residing in West Germany and private health insurance coverage increased discontinuation risk.

Conclusions

Women with metastatic BC aged ≥70 are at a lower risk of BIS treatment discontinuation than younger women.

Adjuvant denosumab in breast cancer (ABCSG-18): a multicentre, randomised, double-blind, placebo-controlled trial

BACKGROUND

Adjuvant endocrine therapy compromises bone health in patients with breast cancer, causing osteopenia, osteoporosis, and fractures. Antiresorptive treatments such as bisphosphonates prevent and counteract these side-effects. In this trial, we aimed to investigate the effects of the anti-RANK ligand antibody denosumab in postmenopausal, aromatase inhibitor-treated patients with early-stage hormone receptor-positive breast cancer.

METHODS

In this prospective, double-blind, placebo-controlled, phase 3 trial, postmenopausal patients with early hormone receptor-positive breast cancer receiving treatment with aromatase inhibitors were randomly assigned in a 1:1 ratio to receive either denosumab 60 mg or placebo administered subcutaneously every 6 months in 58 trial centres in Austria and Sweden. Patients were assigned by an interactive voice response system. The randomisation schedule used a randomly permuted block design with block sizes 2 and 4, stratified by type of hospital regarding Hologic device for DXA scans, previous aromatase inhibitor use, and baseline bone mineral density. Patients, treating physicians, investigators, data managers, and all study personnel were masked to treatment allocation. The primary endpoint was time from randomisation to first clinical fracture, analysed by intention to treat. As an additional sensitivity analysis, we also analysed the primary endpoint on the per-protocol population. Patients were treated until the prespecified number of 247 first clinical fractures was reached. This trial is ongoing (patients are in follow-up) and is registered with the European Clinical Trials Database, number 2005-005275-15, and with ClinicalTrials.gov, number NCT00556374.

FINDINGS

Between Dec 18, 2006, and July 22, 2013, 3425 eligible patients were enrolled into the trial, of whom 3420 were randomly assigned to receive denosumab 60 mg (n=1711) or placebo (n=1709) subcutaneously every 6 months. Compared with the placebo group, patients in the denosumab group had a significantly delayed time to first clinical fracture (hazard ratio [HR] 0·50 [95% CI 0·39-0·65], p<0·0001). The overall lower number of fractures in the denosumab group (92) than in the placebo group (176) was similar in all patient subgroups, including in patients with a bone mineral density T-score of -1 or higher at baseline (n=1872, HR 0·44 [95% CI 0·31-0·64], p<0·0001) and in those with a bone mineral density T-score of less than -1 already at baseline (n=1548, HR 0·57 [95% CI 0·40-0·82], p=0·002). The patient incidence of adverse events in the safety analysis set (all patients who received at least one dose of study drug) did not differ between the denosumab group (1366 events, 80%) and the placebo group (1334 events, 79%), nor did the numbers of serious adverse events (521 vs 511 [30% in each group]). The main adverse events were arthralgia and other aromatase-inhibitor related symptoms; no additional toxicity from the study drug was reported. Despite proactive adjudication of every potential osteonecrosis of the jaw by an international expert panel, no cases of osteonecrosis of the jaw were reported. 93 patients (3% of the full analysis set) died during the study, of which one death (in the denosumab group) was thought to be related to the study drug.

INTERPRETATION

Adjuvant denosumab 60 mg twice per year reduces the risk of clinical fractures in postmenopausal women with breast cancer receiving aromatase inhibitors, and can be administered without added toxicity. Since a main side-effect of adjuvant breast cancer treatment can be substantially reduced by the addition of denosumab, this treatment should be considered for clinical practice.

FUNDING

Amgen.

Cancer Treatment-Induced Bone Loss in women with breast cancer

Osteoporosis is one of the most frequent diseases in postmenopausal women, leading to an increased fracture risk due to the physiologic loss of the bone protective effects of estrogen. Hereby, several risk factors for fracture such as prevalent fracture, low bone mineral density (BMD), age, low body mass index, family history, tendency to falls, smoking, use of SSRIs, glucocorticoid use etc. have been identified. In addition, the further reduction in endogenous estrogens with chemotherapy (CHT), GnRH analoga or aromatase inhibitors (AIs) continuously increases fracture risk. Breast cancer (BC) on the other hand is the most frequent cancer type in women. Recent reports indicate a continuous increased incidence, whereas mortality, due to early diagnosis and treatment improvements, is decreasing. Dependent on specific tumor characteristics, radiation, CHT, antibody treatment as well as endocrine treatment have been included into the adjuvant clinical treatment setting. Some but not all of these cancer-specific treatments interfere with bone turnover, leading to an accelerated bone loss referred to as cancer treatment-induced bone loss (CTIBL). Whereas CHT leads to an unspecific increase in bone resorption, AI reduces residual serum endogenous estrogen level and is associated with a decrease in BMD and increased fracture risk. Independent of the type of AI administered, bone loss is 2-3-fold increased compared with healthy, age-matched postmenopausal controls. Therefore, several guidelines have emerged to help managing CTIBL in women with BC including strategies to identify and treat those at highest risk for fractures. This review summarizes the current knowledge on CTIBL and fracturing risk and indicates preventative strategies.

Bone health in cancer patients: ESMO Clinical Practice Guidelines

There are three distinct areas of cancer management that make bone health in cancer patients of increasing clinical importance. First, bone metastases are common in many solid tumours, notably those arising from the breast, prostate and lung, as well as multiple myeloma, and may cause major morbidity including fractures, severe pain, nerve compression and hypercalcaemia. Through optimum multidisciplinary management of patients with bone metastases, including the use of bone-targeted treatments such as potent bisphosphonates or denosumab, it has been possible to transform the course of advanced cancer for many patients resulting in a major reduction in skeletal complications, reduced bone pain and improved quality of life. Secondly, many of the treatments we use to treat cancer patients have effects on reproductive hormones, which are critical for the maintenance of normal bone remodelling. This endocrine disturbance results in accelerated bone loss and an increased risk of osteoporosis and fractures that can have a significant negative impact on the lives of the rapidly expanding number of long-term cancer survivors. Finally, the bone marrow micro-environment is also intimately involved in the metastatic processes required for cancer dissemination, and there are emerging data showing that, at least in some clinical situations, the use of bone-targeted treatments can reduce metastasis to bone and has potential impact on patient survival.

Persistence with bisphosphonates in patients with metastatic breast cancer: a retrospective database analysis

BACKGROUND

In women with breast cancer and bone metastasis, compliance to antiresorptive treatment is of upmost importance to ensure maximum effectiveness in clinical practice. The aim of our study was to investigate persistence with oral and intravenous bisphosphonates (BIS) in a large group of women with metastatic breast cancer and to identify the determinants of non-persistence.

PATIENTS AND METHODS

We used data from the Disease Analyzer database (IMS Health, Germany), which includes 2,067 general practices and 397 gynaecological practices. From a dataset of 20 million patients, we identified 1,045 patients diagnosed between January 2001 and December 2010 with bone metastasis (ICD 10: C795) following breast cancer (ICD 10: C50) with first-time cancer-related bisphosphonate prescriptions (ATC: M03B4). Of these, 763 patients received intravenous treatment, and 280 patients received oral BIS treatment.

RESULTS

After 1 year, 35.3 % of patients treated with intravenous, and 45.6 % of patients treated with oral bisphosphonates discontinued their therapy (p = 0.002). Multivariate Cox Regression analyses showed a significant increased risk of treatment discontinuation in patients using intravenous BIS (HR: 0.82) compared with oral BIS. Patients younger than 50 (HR: 1.52) were most likely to discontinue treatment compared with the reference group of women over 70. The use of other treatments, such as chemotherapy or hormone therapy, was associated with a decreased risk of treatment discontinuation. Moreover, treatment discontinuation was higher in West Germany compared with East Germany (HR: 1.65) and in patients covered under private health insurance (HR: 1.33).

CONCLUSIONS

Persistence with all bisphosphonate treatments in women with breast cancer and bone metastasis is low and needs to be significantly increased to improved outcomes in clinical practice. Further research is required to understand this complex issue.

Challenges in the treatment of older breast cancer patients

As the population ages, oncologists will be faced with managing an exploding number of older patients with breast cancer. The primary challenge of caring for older cancer patients is providing treatment options that maximize long-term survival while accounting for comorbidities, life expectancy, and effects of treatment. There is a paucity of data from trials on the risks and benefits of effective treatments in elderly breast cancer patients. This article discusses how to evaluate older breast cancer patients and provides guidelines for optimal therapies in the adjuvant and metastatic treatment settings.