Meta-analysis comparing denosumab and zoledronic acid for treatment of bone metastases in patients with advanced solid tumours

Survival impact of pathological fractures in metastatic cancer: a comprehensive meta-analysis

INTRODUCTION

Metastatic patients face the risk of pathological fractures (PF). The incidence of PF varies among different cancer types, impacting patient survival and leading to substantial healthcare costs. However, conflicting findings regarding the survival impact of PF exist, and comprehensive meta-analyses addressing this issue are currently lacking. The aim of this study was to evaluate the survival of metastatic cancer patients with PF.

METHODS

This study adhered to PRISMA guidelines and employed the PICOS strategy for inclusion criteria. A comprehensive search was conducted across multiple databases. The primary focus was on survival outcomes. Statistical analysis employed Review Manager 5.4.1, calculating mean differences for continuous variables and generic inverse variances for hazard ratios. Heterogeneity was assessed using Chi2 and I2 tests.

RESULTS

A total of eight studies with 15,464 patients were included. Unadjusted hazard ratios (HRs) showed that PF increased the risk of mortality 1.45 (95% CI 1.22 to 1.73). Adjusted HRs confirmed significant increase in mortality risk for PF HR 1.31 (95% CI 1.08 to 1.57). The PF group had significant lower mean survival (MD -14.50, 95% CI -22.95 to -6.05). PF increased the risk of mortality in breast cancer (HR 1.52, 95% CI 1.32 to 1.76), prostate cancer (HR 1.38, 95% CI 1.16 to 1.64) and in leiomyosarcoma (HR 5.40, 95% CI 1.80 to 16.2).

CONCLUSION

PF increases the mortality risk and reduces the mean survival of patients with metastatic cancer.

New oxaliplatin-zoledronate derivatives with potential antitumor activity towards bone tumors and metastases

Bone cancer can originate from any cellular element of the bone and may occur sporadically or as a result of degeneration from a precursor lesion. Bone metastases, often stemming from primary cancers such as breast and prostate cancer, are extremely painful and challenging to treat. The treatment of primary bone malignancies typically involves surgery, radiotherapy, chemotherapy and analgesics. Platinum (Pt)-based drugs are effective against bone cancers and metastases but are often limited by severe side effects due to poor specificity. To improve drug targeting and reduce systemic toxicity, bisphosphonate (BP) ligands, which selectively accumulate in bone tissue, have been combined with Pt-based drugs. The combination of Pt drugs with bisphosphonates like zoledronic acid (ZL) could lead to enhanced therapeutic outcomes due to its intrinsic pharmacological activity. In this study, we report the synthesis and full characterization of two new dinuclear Pt(II) complexes that combine ZL with clinically approved oxaliplatin and the drug-candidate kiteplatin, respectively. These complexes were tested for their stability under physiological and acidic conditions, reactivity with 5'-GMP interaction with B- and G-quadruplex DNA models and cytotoxicity against a panel of human tumor cell lines.

A Comparison of the Efficacy and Safety of Denosumab and Zoledronic Acid in Patients with Bone Metastatic Breast Cancer Receiving CDK4/6 Inhibitor Therapy

Background and Objectives: Bone metastases in patients can cause significant quality-of-life declines due to skeletal-related events (SREs). SRE is defined as the occurrence of radiotherapy for bone pain, pathologic fracture, bone surgery, spinal cord compression, or hypercalcemia. Bone-modifying agents (BMAs), such as denosumab and zoledronic acid, are crucial in reducing the frequency and severity of SREs. The inhibition of cyclin-dependent kinase 4/6 (CDK4/6) inhibitors has emerged as the standard treatment for hormone receptor-positive metastatic breast cancer, demonstrating significant improvements in survival outcomes. This study aims to compare the effectiveness of denosumab and zoledronic acid in preventing SRE in patients receiving CDK4/6 inhibitors with endocrine therapy. Materials and Methods: This retrospective study included 328 patients diagnosed with bone metastatic breast cancer receiving first-line CDK4/6 inhibitor therapy (palbociclib or ribociclib). Patients were assigned to receive either subcutaneous denosumab or intravenous zoledronic acid every 4 weeks. Time to the first skeletal-related event post bone-modifying agent initiation, SRE incidence, and the safety data were evaluated. The data were analyzed using independent samples t-tests, chi-square tests, and Kaplan-Meier methods for time-to-event data. Results: In the denosumab group, the median time to the first skeletal-related event was significantly longer than in the zoledronic acid group (44.55 months and 29.16 months, respectively). Denosumab treatment was associated with a statistically significant reduction in the risk of developing the first SRE after bone-modifying agent initiation compared to zoledronic acid (HR: 0.56, p = 0.001). Additionally, ECOG PS and the number of metastatic bone sites were identified as independent prognostic factors for time to the first SRE. The safety profile was consistent with previous studies reported in the literature. Conclusions: Our study demonstrated that when used with CDK4/6 inhibitors, denosumab is associated with a delay in SREs and a lower SRE incidence than zoledronic acid in patients with bone metastases. These findings support the efficacy of denosumab in preventing SREs and suggest that CDK4/6 inhibitors may have distinct effects on the bone microenvironment, particularly when combined with denosumab.

Denosumab vs. Zoledronic Acid for Metastatic Bone Disease: A Comprehensive Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: Metastatic bone disease (MBD) presents significant challenges in patient management, leading to skeletal-related events (SREs), compromised health-related quality of life, and heightened pain experiences. Denosumab (Dmab) and zoledronic acid (ZA) are bone-modifying agents (BMAs) commonly employed to mitigate the sequelae of MBD. Previous meta-analyses have assessed primary outcomes such as overall survival, pathological fractures, radiation to bone, and the time to SREs within studies. However, a single comprehensive analysis comparing their efficacy across multiple primary and secondary outcomes, as well as cost-effectiveness in specific cancer types, has not yet been conducted. Methods: A literature search identified relevant randomized controlled trials (RCTs), and the primary outcomes included overall survival, pathologic fractures, radiation to bone, and the time to SREs within studies. Secondary outcomes included adverse events, pain, analgesia usage, quality of life, and cost. Results: Meta-analysis revealed that Dmab effectively reduced the need for bone-targeted radiation therapy and was superior to ZA in delaying the time to SREs, except in multiple myeloma. Dmab also reduced pathological fracture incidences in breast cancer patients by 39%. Conclusions: Our analysis suggests that while both agents similarly impact overall survival and disease progression, Dmab offers advantages in SRE reduction and improved HRQoL and pain outcomes with lower rates of opioid usage, albeit with higher risks of hypocalcemia and osteonecrosis in some subgroups. The consensus on cost-effectiveness is mixed and varies based on the cancer type and healthcare system, with some studies favoring Dmab's superior efficacy and safety, while others find ZA more cost-effective due to its lower cost. This study underscores the potential of Dmab as a preferred BMA for MBD management, especially for high-risk skeletal complications, while highlighting cancer-specific safety considerations. Further research is warranted to refine cancer-specific BMA use and optimize MBD management strategies.

Denosumab combined with radiotherapy as an alternative to surgery for advanced metastatic bone lesions and pathologic fractures: a retrospective case study of 38 patients

BACKGROUND AND PURPOSE

Pathologic and impending fractures occur in patients with advanced metastatic disease and necessitate surgical interventions with high risk of complications. The aim of this study was to analyze the efficacy of combined treatment with denosumab and radiotherapy as an alternative to surgery in treating bone metastases of the pelvis and extremities.

METHODS

This retrospective cohort study included 38 patients with impending and pathologic fractures due to carcinoma metastases who received monthly injections of denosumab (120 mg/dose) and radiotherapy. Twenty-three patients received denosumab and single-dose radiotherapy of 8 Gy, and 15 patients received denosumab and fractionated radiotherapy. We assessed pain, radiographic signs of fracture healing, survival and complications.

RESULTS

Of the 38 patients 36 experienced pain reduction. Callus formation was observed in 11/17 patients with pathologic fractures, and increased mineralization was found in 12/21 patients with impending fractures. In 23/38 patients, we found both pain reduction and callus formation or increased mineralization. There were no statistically significant differences in treatment outcomes between the patients who received denosumab and single-dose radiotherapy and those who received denosumab and fractionated radiotherapy. The survival rates at 30 days and 1 year were 95% and 56%, respectively.

INTERPRETATION

Combined treatment with denosumab and radiotherapy may reduce pain and promote bone healing in patients with metastatic impending and pathologic fractures. In this combined treatment, the effect of single-dose radiotherapy appears to be comparable to that of fractionated regimens.

Immunotherapy in the Battle Against Bone Metastases: Mechanisms and Emerging Treatments

Bone metastases are a prevalent complication in advanced cancers, particularly in breast, prostate, and lung cancers, and are associated with severe skeletal-related events (SREs), including fractures, spinal cord compression, and debilitating pain. Conventional bone-targeted treatments like bisphosphonates and RANKL inhibitors (denosumab) reduce osteoclast-mediated bone resorption but do not directly impact tumor progression within the bone. This review focuses on examining the growing potential of immunotherapy in targeting the unique challenges posed by bone metastases. Even though immune checkpoint inhibitors (ICIs) have significantly changed cancer treatment, their impact on bone metastases appears limited because of the bone microenvironment's immunosuppressive traits, which include high levels of transforming growth factor-beta (TGFβ) and the immune-suppressing cells, such as regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs). This review underscores the investigation of combined therapeutic approaches that might ease these difficulties, such as the synergy of immune checkpoint inhibitors with agents aimed at bones (denosumab, bisphosphonates), chemotherapy, and radiotherapy, as well as the combination of immune checkpoint inhibitors with different immunotherapeutic methods, including CAR T-cell therapy. This review provides a comprehensive analysis of preclinical studies and clinical trials that show the synergistic potential of these combination approaches, which aim to both enhance immune responses and mitigate bone destruction. By offering an in-depth exploration of how these strategies can be tailored to the bone microenvironment, this review underscores the need for personalized treatment approaches. The findings emphasize the urgent need for further research into overcoming immune evasion in bone metastases, with the goal of improving patient survival and quality of life.

Bone complications of cancer treatment

With the advancements in conventional treatment modalities such as radiation, chemotherapy, and surgery, as well as the emergence of immunotherapy, the overall cure rate for solid tumor malignancies has experienced a significant increase. However, it is unfortunate that exposure to cancer treatments can have detrimental effects on the function of osteoblasts and osteoclasts, disturbing bone metabolic homeostasis in patients, as well as causing damage to bone marrow cells and other bone tissues. Consequently, certain tumor treatment options may pose a risk for subsequent bone diseases. Common bone disorders associated with cancer treatment include osteonecrosis, bone loss, and secondary bone tumors. (1)Cancer treatment-related osteonecrosis is primarily linked to the use of radiation therapy and certain chemicals, such as bisphosphonates, denosumab, antiangiogenic agents, and immunomodulators. It has been observed that high-dose radiation therapy is more likely to result in osteonecrosis. (2)Chemicals and hormones, particularly sex hormones, glucocorticoids, and thyroid hormones or thyrotropic hormones, are among the factors that can contribute to cancer treatment-related bone loss. (3)Secondary bone tumors differ from metastases originating from primary tumors, and radiotherapy plays a significant role in their development, while chemotherapy may also exert some influence. Radiogenic secondary bone tumors are predominantly malignant, with osteosarcoma being the most common type. Chemotherapy may be a risk factor for the relatively rare occurrence of secondary Ewing sarcoma of the bone. These treatment-related bone disorders have a considerable adverse impact on the prognosis of cancer patients. Hence, it is imperative to prioritize the bone health of patients undergoing cancer treatment and give it further attention.

Comparison of the Efficacy of Zoledronate and Denosumab in Patients with Acute Osteoporotic Vertebral Compression Fractures: A Randomized Controlled Trial

Background: The comparison of the efficacy of zoledronate and denosumab for treating osteoporosis is controversial, and few randomized controlled trials have compared these two drugs in practical patients with acute osteoporotic vertebral compression fractures (OVCFs). We conducted a randomized controlled study to compare the efficacy of zoledronate and denosumab in patients with acute OVCF, with a focus on the occurrence of new OVCF. Methods: We enrolled 206 subjects who had their first acute OVCF, without any previous history of osteoporosis medication. The patients were randomly assigned to receive either intravenous zoledronate once a year or subcutaneous denosumab twice a year. We investigated the OVCF recurrence, clinical outcome, bone mineral density (BMD), and bone turnover markers over 12 months. Results: The final cohort comprised 89 participants (mean age of 75.82 ± 9.34 years, including 74 women [83.15%]) in the zoledronate group and 86 patients (mean age of 75.53 ± 10.23 years, including 71 women [82.56%]) in the denosumab group. New OVCFs occurred in 8 patients (8.89%) in the zoledronate group and 11 patients (12.79%) in the denosumab group (odds ratio, 1.485 [95% confidence interval, 0.567-3.891], p = 0.419). No significant difference was observed in the survival analysis between the two groups (p = 0.407). The clinical outcome, including the visual analog scale score for pain and simple radiographic findings, did not differ between the two groups. The changes in BMD and bone turnover markers were also not significantly different between the two groups. Additionally, drug-related adverse events did not differ between the groups in terms of safety. Conclusions: The efficacy of zoledronate was comparable to that of denosumab in terms of the occurrence of new OVCFs, as well as of the overall clinical course in patients with their first acute OVCF. Notably, this study represents the first comparison of these two drugs in patients with acute OVCF. However, further research with large-scale and long-term follow-up is necessary.

Effects of zoledronic acid on osteosarcoma progression and metastasis: systematic review and meta-analysis

Zoledronic Acid (ZA) has been shown to inhibit Osteosarcoma (OSA) progression in preclinical studies. However, the use of ZA as an intervention for OSA treatment and management remains controversial. A systematic review and meta-analysis of randomized-controlled trials comparing the use of ZA with standard treatment vs. standard treatment alone for OSA patients after resection was conducted. Primary outcomes assessed event-free survival (EFS) and overall survival (OS) rates, while secondary outcomes assessed impact of ZA on metastatic spread, histological response and adverse events occurrence. A literature search was conducted using EMBASE, MEDLINE, and the Cochrane Central Register of Controlled Trials. The Cochrane risk of bias tool (version 2) was used to assess trial quality. RevMan v5.4 was used for the meta-analysis. The between-trial heterogeneity was assessed using the Chi2 test and the I2 statistic and the GRADE methodology was utilized to assess certainty of evidence. Two studies were considered eligible for qualitative synthesis and meta-analysis. ZA had no benefit on EFS (HR, 0.95; 95% CI, 0.48-1.88; p-value 0.88), however, when compared to standard treatment it reduced OS (HR, 1.98; 95% CI, 1.49-2.64; p-value < 0.00001). ZA did not deter lung metastasis (RR, 2.56; 95% CI, 0.35-18.60; p-value 0.35), and neither did it increase good histological response (RR, 0.97; 95% CI, 0.90-1.05; p-value 0.48). ZA treatment was associated with higher risk of adverse events. Based on existing data, the use of ZA as adjuvant therapy is not recommended for the treatment of OSA patients.

Recurrent Differentiated Thyroid Cancer: The Current Treatment Options

Differentiated thyroid carcinomas (DTC) have an excellent prognosis, but this is sometimes overshadowed by tumor recurrences following initial treatment (approximately 15% of cases during follow-up), due to unrecognized disease extent at initial diagnosis or a more aggressive tumor biology, which are the usual risk factors. The possible sites of recurrence are local, regional, or distant. Local and regional recurrences can usually be successfully managed with surgery and radioiodine therapy, as are some isolated distant recurrences, such as bone metastases. If these treatments are not possible, other therapeutic options such as external beam radiation therapy or systemic treatments should be considered. Major advances in systemic treatments have led to improved progression-free survival in patients previously considered for palliative treatments; among these treatments, the most promising results have been achieved with tyrosine kinase inhibitors (TKI). This review attempts to give a comprehensive overview of the current treatment options suited for recurrences and the new treatments that are available in cases where salvage surgery is not possible or in cases resistant to radioiodine.

Management of Progressive Radioiodine-Refractory Thyroid Carcinoma: Current Perspective

Patients with thyroid cancer (TC) usually have an excellent prognosis; however, 5-10% of them develop an advanced disease. The prognosis of this subgroup is still favourable if the lesions respond to radioactive iodine (RAI) treatment. Nearly two-thirds of advanced TC patients become RAI-refractory (RAI-R), and their management is challenging. A multidisciplinary approach in the context of a tumour board is essential to define a personalized strategy. Systemic therapy is not always the best option. In case of slow neoplastic growth and low tumour burden, active surveillance may represent a valuable choice. Local approaches might be considered if the disease progression is limited to a single or few lesions, also in combination and during systemic therapy. Antiresorptive treatment may be started in presence of bone metastases. In case of rapid and/or symptomatic progression involving multiple lesions and/or organs, systemic therapy has to be considered, in absence of contraindications. The multi-kinase inhibitors (MKIs) lenvatinib and sorafenib are currently available as first-line treatment for advanced progressive RAI-R TC. Among second-line options, cabozantinib has been recently approved in RAI-R TC who progressed during MKIs targeting the vascular endothelial growth factor receptor (VEGFR). In the last few years, next-generation sequencing (NGS) assays have been increasingly employed, permitting identification of the genetic alterations harboured by TC, with a significant impact on patients' management. Novel selective targeted therapies have been introduced for the treatment of RAI-R TC in selected cases: REarranged during Transfection (RET) inhibitors (selpercatinib and pralsetinib) and Tropomyosin Receptor Kinase (TRK) inhibitors (larotrectinib and entrectinib) have recently expanded the panorama of the therapeutic options. Moreover, immune checkpoint inhibitors (ICIs) have shown promising results, and they are still under investigation.

Biological and Clinical Aspects of Metastatic Spinal Tumors

Simple Summary

Spine metastases are a common life-threatening complication of advanced-stage malignancies and often result in poor prognosis. Symptomatic spine metastases develop in the course of about 10% of malignant neoplasms. Therefore, it is essential for contemporary medicine to understand metastatic processes in order to find appropriate, targeted therapeutic options. Our literature review aimed to describe the up-to-date knowledge about the molecular pathways and biomarkers engaged in the spine’s metastatic processes. Moreover, we described current data regarding bone-targeted treatment, the emerging targeted therapies, radiotherapy, and immunotherapy used for the treatment of spine metastases. We hope that knowledge comprehensively presented in our review will contribute to the development of novel drugs targeting specific biomarkers and pathways. The more we learn about the molecular aspects of cancer metastasis, the easier it will be to look for treatment methods that will allow us to precisely kill tumor cells.

Abstract

Spine metastases are a common life-threatening complication of advanced-stage malignancies and often result in poor prognosis. Symptomatic spine metastases develop in the course of about 10% of malignant neoplasms. Therefore, it is essential for contemporary medicine to understand metastatic processes in order to find appropriate, targeted therapeutic options. Thanks to continuous research, there appears more and more detailed knowledge about cancer and metastasis, but these transformations are extremely complicated, e.g., due to the complexity of reactions, the variety of places where they occur, or the participation of both tumor cells and host cells in these transitions. The right target points in tumor metastasis mechanisms are still being researched; that will help us in the proper diagnosis as well as in finding the right treatment. In this literature review, we described the current knowledge about the molecular pathways and biomarkers engaged in metastatic processes involving the spine. We also presented a current bone-targeted treatment for spine metastases and the emerging therapies targeting the discussed molecular mechanisms.

Evaluation of Diagnostic Workup and Etiology of Hypercalcemia of Malignancy in a Cohort of 167 551 Patients Over 20 Years

Context

Hypercalcemia of malignancy (HCM) has not been studied in a fashion to determine all possible mechanisms of hypercalcemia in any given patient.

Objective

The 2 objectives were to assess the completeness of evaluation and to determine the distribution of etiologies of HCM in a contemporary cohort of patients.

Methods

A retrospective analysis was performed of patients with cancer who developed hypercalcemia over 20 years at a single health system. Laboratory data were electronically captured from medical records to identify cases of parathyroid hormone (PTH)-independent hypercalcemia. The records were then manually reviewed to confirm the diagnosis of HCM, document the extent of evaluation, and determine underlying etiology(ies) of HCM in each patient.

Results

The initial data set included 167 551 adult patients with malignancy, of which 11 589 developed hypercalcemia. Of these, only a quarter (25.4%) had assessment of PTH with a third of the latter (30.9%) indicating PTH-independent hypercalcemia. Of those with PTH-independent hypercalcemia, a third (31.6%) had assessment of PTH-related peptide (PTHrP) and/or 1,25-dihydroxy (1,25-OH) vitamin D and constituted the 153 cases of HCM examined in this study. Eighty-three of these patients had an incomplete evaluation of their HCM. The distribution of etiologies of HCM was therefore determined from the remaining 70 patients who had assessment of all 3 possible etiologies (PTHrP, 1,25-OH vitamin D, and skeletal imaging) and was as follows: PTHrP, 27%; osteolytic metastases, 50%; and 1,25-OH vitamin D, 39%, with combinations of etiologies being common (approximately 20%).

Conclusion

HCM is incompletely evaluated in many patients. The distribution of etiologies of HCM in this report differs significantly from the previous literature, warranting further study to determine whether its causes have indeed changed over time.

Hypocalcemia in a Patient With Metastatic Prostate Cancer From Denosumab Treatment

Denosumab is a humanized monoclonal antibody that binds RANKL to inhibit osteoclast activity. It is indicated for the prevention of skeletal-related events (SRE) in patients with solid tumors who have bone metastasis and in patients with multiple myeloma. Hypocalcemia is one of the known side effects of denosumab, which can be prevented with calcium supplementation.

We present a case of a 72-year-old male with diagnosed metastatic prostate cancer who had received one dose of denosumab 10 days prior to presentation with fatigue, insomnia, and somnolence. His labs showed severe (Grade 4) hypocalcemia, which improved with intravenous calcium supplementation. This case highlights a known but life-threatening side effect of denosumab and the potential need for prolonged calcium monitoring in patients placed on the drug.

Current Management of Bone Metastases from Differentiated Thyroid Cancer

Simple Summary

Patients with bone metastases (BMs) from differentiated thyroid carcinoma (DTC) can live longer than those with BMs from other cancers. BMs from DTC create destructive lesions and easily cause intractable pain and neurological symptoms, including paralysis. These symptoms related to BMs affect mortality directly and indirectly by hampering the application of systemic therapies. Therefore, long-term local control of BMs in patients with DTC is desired, especially in patients with single or a small number of metastases. Local treatments for BMs have recently become advanced and sophisticated in surgery, radiotherapy, and percutaneous procedures. These therapies, either alone or in combination with other treatments, can effectively improve, or prevent the deterioration of, the performance status and quality of life of patients with DTC-BM. Among local therapies, complete surgical resection and stereotactic radiosurgery are the mainstay for achieving long-term control of DTC-BM.

Abstract

After the lung, the skeleton is the second most common site of distant metastases in differentiated thyroid carcinoma (DTC). Patients with osteolytic bone metastases (BMs) from thyroid carcinoma often have significantly reduced performance status and quality of life. Recent advancements in cancer therapy have improved overall survival in multiple cancer subtypes, including thyroid cancer. Therefore, long-term local control of thyroid BMs is desired, especially in patients with a single metastasis or oligometastases. Here, we reviewed the current management options for DTC-BMs and especially focused on local treatments for long-term local tumor control from an orthopedic tumor surgeon’s point of view. Metastasectomy and stereotactic radiosurgery can be performed either alone or in combination with radioiodine therapy and kinase inhibitors to cure skeletal lesions in selected patients. Percutaneous procedures have been developed in recent years, and they can also have a curative role in small BMs. Recent advancements in local therapies have the potential to provide not only long-term local tumor control but also a better prognosis.

Comparison of denosumab and zoledronic acid for the treatment of solid tumors and multiple myeloma with bone metastasis: a systematic review and meta-analysis based on randomized controlled trials

Objective

To compare the efficacy and safety between denosumab and zoledronic acid for advanced cancer with bone metastasis.

Methods

MEDLINE, EMBASE, and the Cochrane library databases were searched for randomized controlled trials up to December 2020 that compared denosumab and zoledronic acid in the treatment of advanced cancer with bone metastasis. The following clinical outcomes were extracted for analysis: time to first skeletal-related event, time to first-and-subsequent skeletal-related events, overall survival, and disease progression. Safety outcomes including incidence of adverse events, serious adverse events, acute-phase reactions, renal toxicity, osteonecrosis of the jaw, and hypocalcemia were also extracted.

Results

Four randomized controlled trials involving 7201 patients were included. The overall analysis showed that denosumab was superior to zoledronic acid in delaying time to first skeletal-related event (hazard ratio = 0.86; 95% confidence interval, 0.80–0.93; P < 0.01) and time to first-and-subsequent skeletal-related events (risk ratio 0.87; 95% confidence interval 0.81–0.93; P < 0.01). Denosumab was associated with lower incidence of renal toxicity (risk ratio 0.69; 95% confidence interval 0.54–0.87; P < 0.01) and acute phase reaction (risk ratio 0.47; 95% confidence interval 0.38–0.56; P < 0.01), but higher incidence of hypocalcemia (risk ratio 1.78; 95% confidence interval 1.33–2.38; P < 0.01) and osteonecrosis of the jaw (risk ratio 1.41; 95% confidence interval 1.01–1.95; P = 0.04). No significant differences were found in overall survival, time to disease progression, or incidence of adverse events and serious adverse events between denosumab and zoledronic acid.

Conclusions

Compared with zoledronic acid, denosumab is associated with delayed first-and-subsequent skeletal-related events, lower incidence of renal toxicity, and acute phase reaction, but higher incidence of hypocalcemia and osteonecrosis of the jaw. Hence, denosumab seems to be a promising choice for advanced cancer with bone metastasis. Nonetheless, more randomized controlled trials are needed for further evaluation.

Bone metastases from differentiated thyroid carcinoma: current knowledge and open issues

Bone represents the second most common site of distant metastases in differentiated thyroid cancer (DTC). The clinical course of DTC patients with bone metastases (BM) is quite heterogeneous, but generally associated with low survival rates. Skeletal-related events might be a serious complication of BM, resulting in high morbidity and impaired quality of life. To achieve disease control and symptoms relief, multimodal treatment is generally required: radioiodine therapy, local procedures-including surgery, radiotherapy and percutaneous techniques-and systemic therapies, such as kinase inhibitors and antiresorptive drugs. The management of DTC with BM is challenging: a careful evaluation and a personalized approach are essential to improve patients' outcomes. To date, prospective studies focusing on the main clinical aspects of DTC with BM are scarce; available analyses mainly include cohorts assembled over multiple decades, small samples sizes and data about BM not always separated from those regarding other distant metastases. The aim of this review is to summarize the most recent evidences and the unsolved questions regarding BM in DTC, analyzing several key issues: pathophysiology, prognostic factors, role of anatomic and functional imaging, and clinical management.

Meta-analysis of clinical trials to assess denosumab over zoledronic acid in bone metastasis

Background Bone metastases-induced skeletal complications result in reduced patient survival, lower quality of life, and an increase in healthcare costs. Previously, zoledronic acid (ZA) was the standard choice of treatment for bone metastases, but another drug, denosumab, has also shown promise. However, the clinical utility of these two drugs requires further exploration. Aim of the review Due to the lack of direct comparisons regarding the efficacy of these drugs in both solid tumors and multiple myeloma (MM), we herein tried to conduct a meta-analysis to compare their efficacy in parallel for bone metastases treatment in both solid tumor and MM patients. Methods Multiple databases including Cochrane Library, MEDLINE, EMBASE, and Web of Science were searched to identify randomized controlled trials (RCTs) reported up to March 2019 directly comparing denosumab with ZA in solid tumors and MM. Information about the following events was primarily searched: time to first on-study skeletal-related event (SRE), time to first and subsequent SREs, and overall survival. Information about secondary outcomes including disease progression, pain, health-related quality of life, and adverse events was also recorded. Results Overall, we analyzed data from four distinct RCTs including 7441 patients, and our analysis revealed that patients in the denosumab group had a significantly delayed incidence to the first and subsequent SREs. In addition, denosumab resulted in a higher incidence of hypocalcemia and osteonecrosis of the jaw (ONJ), and a lower incidence of renal toxicity and acute phase reactions, in comparison to ZA. Conclusion Overall, denosumab showed superiority in delaying the first and subsequent SREs, and hence seems to be a promising choice for managing bone metastases in both solid tumors and MM. However, it can induce a higher incidence of ONJ and hypocalcaemia, but these are preventable and manageable effects.

Bone Metastases: Mechanisms of the Metastatic Process, Imaging and Therapy

The mechanisms by which tumors metastasize to bone are complex. Upon the successful establishment of metastatic deposits in the skeleton, detection of the disease becomes essential for therapeutic planning. The roles of CT, skeletal scintigraphy, SPECT/CT, MRI, PET/CT and PET/MRI will be reviewed. Therapeutic response criteria specifically designed to evaluate bone metastases (MD Anderson/MDA criteria) can guide image interpretation. Knowledge of therapeutic strategies such as systemic therapy with bisphosphonates or radiopharmaceuticals, radiation therapy, surgery, and percutaneous interventions such as vertebroplasty and radiofrequency ablation can help the radiologist produce reports that will provide maximum benefit to clinicians and patients.

Denosumab Versus Zoledronic Acid in the Prevention of Skeletal-related Events in Vulnerable Cancer Patients: A Meta-analysis of Randomized, Controlled Trials

PURPOSE

Bone metastases from solid tumors and multiple myeloma (MM) represent an important source of morbidity. The present meta-analysis was performed with the purpose of comparing the efficacy and tolerability of denosumab versus zoledronic acid (ZA) in the prevention of skeletal-related events (SREs) in patients with bone metastases secondary to solid tumors or bone lesions in multiple myeloma.

METHODS

We searched PubMed, PubMed Central, EMBASE, the Cochrane Library, and ClinicalTrials.gov for relevant studies published until April 23, 2020. We included randomized, controlled trials that investigated the efficacy and tolerability of denosumab 120 mg SC versus ZA 4 mg IV, given every 4 weeks, in patients with bone lesions in multiple myeloma or bone metastases secondary to advanced solid tumors. Two reviewers independently identified studies, assessed the risk for bias, and extracted the data. Times to event outcomes were analyzed using hazard ratios (HRs) and 95% CIs. We analyzed tolerability outcomes using risk ratios (RRs) and 95% CIs, with a fixed-effects model.

FINDINGS

Four randomized, controlled trials (7379 patients) were identified as suitable for analysis. The pooled data indicated that denosumab was more favorable than ZA in delaying the time to first on-study SRE (HR = 0.86; 95% CI, 0.80-0.93; P = 0.0001) as well as the time to first and subsequent on-study SREs (HR = 0.83; 95% CI, 0.76-0.90; P < 0.0001); however, the results on overall survival and disease progression were similar between the 2 drugs. Additionally, denosumab was associated with lower risks for bone pain (risk ratio [RR] = 0.88; 95% CI, 0.80-0.97; P = 0.01), osteonecrosis of the jaw (RR = 0.75; 95% CI, 0.61-0.93; P = 0.007), and acute-phase reactions (RR = 0.47; 95% CI, 0.40-0.56; P < 0.00001).

IMPLICATIONS

Compared with ZA, denosumab demonstrated efficacy in significantly delaying on-study SREs. Furthermore, it showed a better tolerability profile, despite being associated with potential yet manageable adverse events. This study was registered with PROSPERO (identifier: CRD42019126390).

Medication-related osteonecrosis of the jaws (MRONJ) in cancer patients treated with denosumab VS. zoledronic acid: A systematic review and meta-analysis

Background

The aim of the present study was to analyse the incidence, risk ratio (RR) and prognoses of two types of medication-related osteonecrosis of the jaws (MRONJ): denosumab-related osteonecrosis of the jaws (DRONJ) and Bisphosphonate-Related Osteonecrosis of the Jaws (BRONJ) in cancer patients under treatment with denosumab or zoledronic acid (ZA).

Material and Methods

An electronic and manual search was conducted for randomized controlled trials (RCTs) until May 2019. Assessment of the identified studies, risk of bias and data extraction were performed independently by two reviewers. The incidence of DRONJ and BRONJ and the RR to develop MRONJ were calculated at 1 year, 2 years and 3 years of exposure. It was also calculated the odds ratio (OR) of their respective prognoses. They were calculated normalizing the values of the individual studies to 1 year, 2 years or 3 years when necessary through robust regression models using a statistical program.

Results

From 1.277 references identified, 8 RCTs were included, which comprised a total of 13.857 patients with a variety of neoplasms. The incidence of DRONJ in cancer patients under treatment with denosumab ranged from 0.5 to 2.1% after 1 year, 1.1 to 3.0% after 2 years, and 1.3 to 3.2% after 3 years of exposure. The incidence of BRONJ in cancer patients under treatment with ZA ranged from 0.4 to 1.6% after 1 year of exposure, 0.8 to 2.1% after 2 years, and 1.0 to 2.3% after 3 years of exposure. Statistically significant differences were found between denosumab and ZA in the risk of developing MRONJ after 1, 2 and 3 years of exposure. Nevertheless, there were no significant differences in terms of patient prognosis.

Conclusions

Denosumab is associated with a significantly higher risk of developing MRONJ compared to ZA. Nevertheless, no differences were found in its prognoses.

Key words:Denosumab, zoledronic acid, bisphosphonate-associated osteonecrosis of the Jaws, medication-related osteonecrosis of the jaws, neoplasms.

Basic and clinical associations between bone and cancer

Bone is one of the most common distant organs in which tumor cells tend to metastasize depending on complicated immune system and bone microenvironments. Clinical symptoms such as severe pain and bone fractures associated with bone metastases severely affect patients' quality of life. According to the pathological types of bone destruction caused by the biological characteristics of different primary cancer cells, bone metastases are classified as osteolytic, osteoblastic and mixed types. Herein, we discuss the molecular mechanisms of bone metastasis and the therapeutic strategy with focus on bone metabolism.

Zoledronic Acid Improves Muscle Function in Healthy Mice Treated with Chemotherapy

Carboplatin is a chemotherapy drug used to treat solid tumors but also causes bone loss and muscle atrophy and weakness. Bone loss contributes to muscle weakness through bone-muscle crosstalk, which is prevented with the bisphosphonate zoledronic acid (ZA). We treated mice with carboplatin in the presence or absence of ZA to assess the impact of bone resorption on muscle. Carboplatin caused loss of body weight, muscle mass, and bone mass, and also led to muscle weakness as early as 7 days after treatment. Mice treated with carboplatin and ZA lost body weight and muscle mass but did not lose bone mass. In addition, muscle function in mice treated with ZA was similar to control animals. We also used the anti-TGFβ antibody (1D11) to prevent carboplatin-induced bone loss and showed similar results to ZA-treated mice. We found that atrogin-1 mRNA expression was increased in muscle from mice treated with carboplatin, which explained muscle atrophy. In mice treated with carboplatin for 1 or 3 days, we did not observe any bone or muscle loss, or muscle weakness. In addition, reduced caloric intake in the carboplatin treated mice did not cause loss of bone or muscle mass, or muscle weakness. Our results show that blocking carboplatin-induced bone resorption is sufficient to prevent skeletal muscle weakness and suggests another benefit to bone therapy beyond bone in patients receiving chemotherapy. © 2019 American Society for Bone and Mineral Research.

Elevated levels of circulating fibroblast growth factor 23 with hypercalcemia following discontinuation of denosumab

We report a case of a 47-year-old woman with hypercalcemia 6 months after discontinuation of denosumab. She underwent right mastectomy for breast cancer and had received aromatase inhibitor and denosumab therapy for 5 years. Thirst, appetite loss, and bilateral ankle pain began few months after cessation of denosumab. She was admitted to the hospital for hypercalcemia and hyperthyroidism 6 months after the last dose of denosumab. Laboratory investigations revealed hypercalcemia, normophosphatemia, normal renal function, and elevated levels of fibroblast growth factor 23 (FGF-23). Serum tartrate-resistant acid phosphatase 5b and urine N-terminal cross-linked telopeptide of type I collagen were both elevated, and bone scintigraphy revealed increase of whole bone uptake. Radiological examinations showed no recurrence of breast cancer or tumors that secrete intact PTH or FGF-23. Hypercalcemia, which lasted for 1 month, was refractory to discontinuation of the aromatase inhibitor, normalization of thyroid hormone levels, saline hydration, and calcitonin administration, but was effectively treated with zoledronic acid. Abnormal uptake on bone scintigraphy and ankle pain both resolved a few months after treatment, and hypercalcemia has not recurred in the ensuing 2 years. In conclusion, we found elevated levels of circulating FGF-23 with hypercalcemia following the discontinuation of denosumab. FGF-23 might be a surrogate marker for massive bone resorption triggered by discontinuation of long-term denosumab treatment.

Bone metastases and skeletal-related events: incidence and prognosis according to histological subtype of lung cancer

AIM

Estimate the incidence of bone metastases (BM) and skeletal-related events according to the histological subtype of lung cancer and its impact on patient survival.

PATIENTS & METHODS

Retrospective cohort study was carried out with patients diagnosed with lung cancer. Cumulative incidence, Kaplan-Meier survival analysis and the risk of death were estimated.

RESULTS

In non-small-cell lung cancer (NSCLC), the cumulative incidence of BM during follow-up was 23.8% at 24 months; in small-cell lung cancer, it was 18.5%. The presence of BM in patients with NSCLC was associated with an increased risk of death (hazard ratio: 1.25; 95% CI: 1.04-1.49; p = 0.013).

CONCLUSION

This study revealed a high incidence of BM and skeletal-related events. BM was associated with a poor prognosis in NSCLC patients.

LC-MS/MS method for denosumab quantitation in human serum with rapid protein digestion using immobilized trypsin

BACKGROUND

Proteomics-based LC-MS/MS methods using trypsin solution have some problems including ion suppression and long protein digestion times. Few practical methods to quantify denosumab in human serum have been published.

METHODOLOGY

Immunoglobulins in serum were extracted using immobilized protein G. Denatured, reduced and alkylated serum samples were digested with immobilized trypsin for 14 min. A denosumab-unique peptide was identified using a Fourier transform mass spectrometer as a signature peptide. The signature peptide was quantitated with a hybrid triple-quadrupole/linear ion-trap mass spectrometer.

CONCLUSION

A rapid and practical proteomics-based LC-MS/MS method using immobilized trypsin for denosumab quantitation in human serum was developed. The present method has an acceptable analytical performance and can be helpful for the determination of serum denosumab in clinical settings.

Denosumab versus bisphosphonates in patients with advanced cancers-related bone metastasis: systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Bone metastasis is reported to be associated with poor quality of life, and increased risk of hospitalization. We aim to synthesize evidence from published randomized controlled trials (RCTs) which compared the efficacy of denosumab versus bisphosphonates in patients with advanced cancers.

METHODS

We searched for all published RCTs in the following electronic databases: PubMed, Scopus, Web of Science, and Cochrane Central. Retrieved records were screened for eligibility. Time-to-event data were pooled as hazard ratio (HR) using the generic inverse-variance method and dichotomous data were pooled as relative risk (RR) in a random-effect model. We used Review Manager 5.3 for windows.

RESULTS

Six unique RCTs with a total of 7722 patients were included. Overall effect estimates favored denosumab group in comparison to intravenous (IV) bisphosphonates in the following terms: time to first skeletal-related events (HR 0.92, 95% CI [0.86, 0.98], p = 0.01), time to subsequent skeletal-related event (RR 0.92, 95% CI [0.86, 0.99], p = 0.03), and radiation to bone (RR 0.81, 95% CI [0.71, 0.92], p = 0.02). Denosumab group was associated with increased risk of grade 3 or 4 hypocalcaemia (RR 1.99, 95% CI [1.11, 3.54], p = 0.02) and reduced risk of renal impairment or toxicity (RR 0.75, 95% CI [0.61, 0.91], p = 0.003) in comparison to IV bisphosphonates group. Pooled studies were homogenous.

CONCLUSION

Denosumab showed a favorable significant impact on delaying the time to first skeletal-related event and reducing the incidence of radiation to the bone event in comparison to bisphosphonates, with similar efficacy regarding overall survival and time to disease progression. Further large-scale and long-term studies are needed to clarify the long-term efficacy and safety of both regimens.

Retrospective Review of Atypical Femoral Fracture in Metastatic Bone Disease Patients Receiving Denosumab Therapy

BACKGROUND

Denosumab therapy is used to reduce skeletal-related events in metastatic bone disease (MBD). There have been reports of atypical femoral fracture (AFF) in osteoporotic patients treated with denosumab but none in the context of higher dose and more frequent denosumab therapy for MBD. The goal of this study was to assess the incidence of AFF in MBD.

PATIENTS AND METHODS

We conducted a retrospective review of 253 patients who received a minimum of 12 doses of denosumab at 120 mg each for MBD. To identify patients with asymptomatic atypical stress reactions in the lateral subtrochanteric femur (which precede fractures), we reviewed the skeletal images of 66 patients who had received at least 21 doses of denosumab for AFF features.

RESULTS

These patients received a median of 17 doses, with a median treatment duration of 23 months. There was 1 case of undiagnosed clinical AFF detected after chart review and 2 cases of subclinical atypical femoral stress reaction observed on imaging review after 23 doses of denosumab over 33 months, 28 doses over 27 months, and 21 doses over 21 months, respectively. Scout computed tomography films showed diffuse cortical thickening of diaphysis with localized periosteal reaction of lateral femoral cortex. Bone scan and magnetic resonance imaging scan of 2 patients with stress reactions confirmed the diagnosis.

CONCLUSION

The incidence of clinical AFF in this context is 0.4% (1/253; 95% confidence interval [CI] 0.1%-2.2%), and the incidence of atypical femoral stress reaction based on imaging review is 4.5% (3/66; 95% CI 1.6%-12.5%). Clinicians should be aware of the clinical prodrome (which may or may not be present) and antecedent imaging changes associated with AFF. The Oncologist 2017;22:438-444Implications for Practice: Among patients with metastatic bone disease treated with denosumab, cases of clinical and subclinical atypical femoral fracture (AFF) are rare. The one detected case of clinical fracture went unrecognized despite prodromic symptoms. Clinicians should be aware of (a) the potential prodrome of anterior thigh/groin pain and (b) subclinical imaging changes in the lateral femur, both of which may precede clinical AFF.