Denosumab versus zoledronic acid for treatment of bone metastases in men with castration-resistant prostate cancer: a randomised, double-blind study

Survey of the association between tooth extraction and development of medication-related osteonecrosis of the jaw in patients undergoing cancer treatment with bone-modifying agents

OBJECTIVE

This study aimed to verify whether tooth extraction before the administration of bone-modifying agents (BMA) was effective in preventing the onset of medication-related osteonecrosis of the jaw (MRONJ).

MATERIALS AND METHODS

This retrospective study included patients with a history of receiving BMA for cancer treatment. The patients were classified into three groups based on the timing of tooth extraction: no tooth extraction before the onset of MRONJ, tooth extraction before the administration of BMA, and tooth extraction after the administration of BMA. The incidence of MRONJ was compared between the groups. Fisher's exact test and Bonferroni correction were used to test for differences in proportions between the three groups.

RESULTS

The total number of subjects was 123. Twenty-four patients (19.5%) developed MRONJ. The incidence rates were 12.3% (10/81), 17.9% (5/28), and 64.3% (9/14) in the non-extraction group, the extraction before BMA administration group, and the extraction after BMA administration group, respectively, showing statistically significant differences between the extraction after BMA administration group and the non-extraction groups and between the extraction after BMA administration group and the extraction before BMA administration group (p < 0.001, p = 0.0049). On the other hand, there was no statistically significant difference in incidence between the non-extraction and the extraction before BMA administration group (p = 0.5274).

CONCLUSIONS

Tooth extraction before the administration of BMA is effective in preventing the onset of MRONJ in patients receiving BMA for cancer treatment. Prevention of MRONJ development in patients receiving BMA for cancer treatment contributes to the maintenance of patients' quality of life.

Balancing Hormone Therapy: Mitigating Adverse Effects of Androgen-Deprivation Therapy and Exploring Alternatives in Prostate Cancer Management

Androgen-deprivation therapy (ADT) is well established as the standard of care in metastatic prostate cancer (PCa) management; however, ADT has significant adverse effects (AEs) that must be addressed. This review aims to highlight opportunities to mitigate AEs of ADT and explore alternatives in PCa management. Specifically, we discuss behavioral and pharmacologic strategies for mitigating ADT AEs as well as ADT-sparing approaches for hormone-sensitive and castration-resistant PCa. Equipped with effective mitigation strategies and possible alternatives, clinicians and researchers can optimize health-related quality of life for patients currently receiving ADT for PCa and consider treatments that spare patients from AEs of ADT.

Management of cancer treatment-induced bone loss in patients with breast and hormone sensitive prostate cancer: AIOM survey

PURPOSE

Cancer treatment-induced bone loss is a side effect of hormonal therapy that can severely affect patients' quality of life. The aim of this survey was to obtain an updated picture of management of bone health in patients with breast cancer undergoing adjuvant hormonal therapy and in patients with hormone sensitive prostate cancer according to Italian oncologists.

METHODS

Our survey was made up of 21 multiple-choice questions: the first part dealt with the respondents' characteristics, while the second with management of bone health in the described setting. An invitation to complete the survey was sent by e-mail to 2336 oncologists, members of Italian Association of Medical Oncology, in October 2022.

RESULTS

Overall, 121 (5.2%) Italian oncologists completed the survey. In most cases (57%) the oncologist personally took charge of the management of bone health in patients at risk for cancer treatment-induced bone loss. At the beginning of hormonal therapy, most respondents reported to require bone health diagnostic exams, such as dual-energy X-ray absorptiometry (89%), repeated with different timing. Main reported reasons (not mutually exclusive) for prescribing antiresorptive drugs were modifying fracture risk (87%), densitometry values (75%) or prognosis (34%). Answers about the management of antiresorptive therapy were heterogeneous.

CONCLUSION

A heterogeneous approach on the management of cancer treatment-induced bone loss in Italy arises from this survey. This scenario highlights the need for a major consensus of the Italian scientific community on the diagnostic and therapeutic approach of cancer treatment-induced bone loss and for a greater awareness of this topic among Italian oncologists.

Incidence and risk factors for bone metastases at presentation in solid tumors

Introduction

Bone metastases are associated with increased morbidity and decreased quality of life in patients with solid tumors. Identifying patients at increased risk of bone metastases at diagnosis could lead to earlier interventions. We sought to retrospectively identify the incidence and predictive factors for bone metastases at initial diagnosis in a large population-based dataset.

Methods

The Surveillance, Epidemiology, and End Results (SEER) database was used to identify patients 18 years-old or older diagnosed with solid cancers from 2010 to 2019. Patients with hematologic malignancies and primary tumors of the bone were excluded. We calculated the incidence and predictive factors for bone metastases according to demographic and tumor characteristics.

Results

Among 1,132,154 patients identified, 1,075,070 (95.0%) had known bone metastasis status and were eligible for the study. Bone metastases were detected in 55,903 patients (5.2% of those with known bone metastases status). Among patients with bone metastases, the most common primary tumors arose from lung (44.4%), prostate (19.3%), breast (12.3%), kidney (4.0%), and colon (2.2%). Bone metastases at presentation were most common in small cell lung cancer (25.2%), non-small cell lung cancer (18.0%), and esophageal adenocarcinoma (9.4%). In addition to stage classification, predictors for bone metastases included Gleason score (OR 95.7 (95% CI 73.1 - 125.4) for Grade Group 5 vs 1 and OR 42.6 (95% CI 32.3 - 55.9) for Group 4 vs 1) and PSA (OR 14.2 (95% CI 12.6 - 16.0) for PSA > 97 vs 0 - 9.9) for prostate cancer, HER2 and hormonal receptor (HR) status (OR 2.2 (95% CI 1.9 - 2.6) for HR+/HER2+ vs HR-/HER2-) for breast cancer, histology (OR 2.5 (95% CI 2.3 - 2.6) for adenocarcinoma vs squamous) for lung cancer, and rectal primary (OR 1.2 (95% 1.1 - 1.4) vs colon primary) and liver metastases (OR 8.6 (95% CI 7.3 - 10.0) vs no liver metastases) for colorectal tumors.

Conclusions

Bone metastases at presentation are commonly seen in solid tumors, particularly lung, prostate, breast, and kidney cancers. Clinical and pathologic factors are associated with a significantly increased risk for bone metastases.

Engineering small-molecule and protein drugs for targeting bone tumors

Bone cancer is common and severe. Both primary (e.g., osteosarcoma, Ewing sarcoma) and secondary (e.g., metastatic) bone cancers lead to significant health problems and death. Currently, treatments such as chemotherapy, hormone therapy, and radiation therapy are used to treat bone cancer, but they often only shrink or slow tumor growth and do not eliminate cancer completely. The bone microenvironment contributes unique signals that influence cancer growth, immunogenicity, and metastasis. Traditional cancer therapies have limited effectiveness due to off-target effects and poor distribution on bones. As a result, therapies with improved specificity and efficacy for treating bone tumors are highly needed. One of the most promising strategies involves the targeted delivery of pharmaceutical agents to the site of bone cancer by introduction of bone-targeting moieties, such as bisphosphonates or oligopeptides. These moieties have high affinities to the bone hydroxyapatite matrix, a structure found exclusively in skeletal tissue, and can enhance the targeting ability and efficacy of anticancer drugs when combating bone tumors. This review focuses on the engineering of small molecules and proteins with bone-targeting moieties for the treatment of bone tumors.

EAU-EANM-ESTRO-ESUR-ISUP-SIOG Guidelines on Prostate Cancer. Part II-2024 Update: Treatment of Relapsing and Metastatic Prostate Cancer

BACKGROUND AND OBJECTIVE

The European Association of Urology (EAU)-European Association of Nuclear Medicine (EANM)-European Society for Radiotherapy and Oncology (ESTRO)-European Society of Urogenital Radiology (ESUR)-International Society of Urological Pathology (ISUP)-International Society of Geriatric Oncology (SIOG) guidelines on the treatment of relapsing, metastatic, and castration-resistant prostate cancer (PCa) have been updated. Here we provide a summary of the 2024 guidelines.

METHODS

The panel performed a literature review of new data, covering the time frame between 2020 and 2023. The guidelines were updated and a strength rating for each recommendation was added on the basis of a systematic review of the evidence.

KEY FINDINGS AND LIMITATIONS

Risk stratification for relapsing PCa after primary therapy may guide salvage therapy decisions. New treatment options, such as androgen receptor-targeted agents (ARTAs), ARTA + chemotherapy combinations, PARP inhibitors and their combinations, and prostate-specific membrane antigen-based therapy have become available for men with metastatic PCa.

CONCLUSIONS AND CLINICAL IMPLICATIONS

Evidence for relapsing, metastatic, and castration-resistant PCa is evolving rapidly. These guidelines reflect the multidisciplinary nature of PCa management. The full version is available online (http://uroweb.org/guideline/ prostate-cancer/).

PATIENT SUMMARY

This article summarises the 2024 guidelines for the treatment of relapsing, metastatic, and castration-resistant prostate cancer. These guidelines are based on evidence and guide doctors in discussing treatment decisions with their patients. The guidelines are updated every year.

Bone mineral density as an individual prognostic biomarker in NSCLC patients treated with immune checkpoint inhibitors

Background

Immune checkpoint inhibitors (ICIs) have left a deep impression in the treatment of non-small cell lung cancer (NSCLC), however, not all patients benefit from it. The purpose of this study was to investigate the prognostic value of baseline bone mineral density (BMD) derived from chest computed tomography (CT) scans in NSCLC patients treated with ICIs.

Methods

This study included patients with advanced NSCLC who underwent ICI treatment at the Wuhan Union Hospital from March 2020 to October 2022. Baseline BMD was evaluated at non-contrast chest CT at the level of first lumbar vertebra. Patients were divided into BMD-lower group and BMD-higher group according to the optimal cutoff value calculated by X-tile software. Baseline characteristics of the two groups were compared and variables between the two groups were balanced by propensity score matching (PSM) analysis. We calculated the objective response rate (ORR) and disease control rate (DCR) of the two groups and analyzed overall survival (OS) and progression-free survival (PFS) using BMD and other clinical indexes through Cox regression models and Kaplan-Meier survival curves.

Results

A total of 479 patients were included in this study, and all patients were divided into BMD-lower group (n=270) and BMD-higher group (n=209). After PSM analysis, each group consisted of 150 patients. ORR (43.3% vs. 43.5% before PSM, P = 0.964; 44.7% vs. 44.7% after PSM, P = 1.000) and DCR (91.1% vs. 94.3% before PSM, P = 0.195; 93.3% vs. 96.7% after PSM, P =0.190) were similar in two groups. There was no statistically significant relationship between BMD degree and PFS before (16.0 months vs. 18.0 months, P = 0.067) and after PSM analysis (17.0 months vs. 19.0 months, P = 0.095). However, lower BMD was associated with shorter OS both before (20.5 months vs. 23.0 months, P< 0.001) and after PSM analysis (20.0 months vs. 23.0 months, P = 0.008).

Conclusion

Lower baseline BMD is associated with worse clinical outcomes in NSCLC patients treated with ICIs. As a reliable and easily obtained individual prognostic biomarker, BMD can become a routine detection indicator before immunotherapy.

Efficacy, Safety, and Population Pharmacokinetics of MW032 Compared With Denosumab for Solid Tumor-Related Bone Metastases: A Randomized, Double-Blind, Phase 3 Equivalence Trial

Importance

The bioequivalence of denosumab biosimilar has yet to be studied in a 53-week, multicenter, large-scale, and head-to-head trial. A clinically effective biosimilar may help increase access to denosumab in patients with solid tumor-related bone metastases.

Objectives

To establish the biosimilarity of MW032 to denosumab in patients with solid tumor-related bone metastases based on a large-scale head-to-head study.

Design, Setting, and Participants

In this 53-week, randomized, double-blind, phase 3 equivalence trial, patients with solid tumors with bone metastasis were recruited from 46 clinical sites in China. Overall, 856 patients were screened and 708 eligible patients were randomly allocated to receive either MW032 or denosumab.

Interventions

Patients were randomly assigned (1:1) to receive MW032 or reference denosumab subcutaneously every 4 weeks until week 49.

Main Outcomes and Measures

The primary end point was percentage change from baseline to week 13 of natural logarithmic transformed urinary N-telopeptide/creatinine ratio (uNTx/uCr).

Results

Among the 701 evaluable patients (350 in the MW032 group and 351 in the denosumab group), the mean (range) age was 56.1 (22.0-86.0) years and 460 patients were women (65.6%). The mean change of uNTx/uCr from baseline to week 13 was -72.0% (95% CI, -73.5% to -70.4%) in the MW032 group and -72.7% (95% CI, -74.2% to -71.2%) in the denosumab group. These percent changes corresponded to mean logarithmic ratios of -1.27 and -1.30, or a difference of 0.02. The 90% CI for the difference (-0.04 to 0.09) was within the equivalence margin (-0.13 to 0.13); the mean changes of uNTx/uCr and bone-specific alkaline phosphatase (s-BALP) at each time point were also similar during 53 weeks. The differences of uNTx/uCr change were 0.015 (95% CI, -0.06 to 0.09), -0.02 (95% CI, -0.09 to 0.06), -0.05 (95% CI, -0.13 to 0.03) and 0.001 (95% CI, -0.10 to 0.10) at weeks 5, 25, 37, and 53, respectively. The differences of s-BALP change were -0.006 (95% CI, 0.06 to 0.05), 0.00 (95% CI, -0.07 to 0.07), -0.085 (95% CI, -0.18 to 0.01), -0.09 (95% CI, -0.20 to 0.02), and -0.13 (95% CI, -0.27 to 0.004) at weeks 5, 13, 25, 37 and 53, respectively. No significant differences were observed in the incidence of skeletal-related events (-1.4%; 95% CI, -5.8% to 3.0%) or time to first on-study skeletal-related events (unadjusted HR, 0.86; P = .53; multiplicity adjusted HR, 0.87; P = .55) in the 2 groups.

Conclusions and Relevance

MW032 and denosumab were biosimilar in efficacy, population pharmacokinetics, and safety profile. Availability of denosumab biosimilars may broaden the access to denosumab and reduce the drug burden for patients with advanced tumors.

Trial Registration

ClinicalTrials.gov Identifier: NCT04812509.

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.

Recurrent severe hypocalcemia following chemotherapy regimen changes in advanced breast cancer: two case reports

BACKGROUND

As an oncologic emergency related to abnormalities in calcium metabolism, hypercalcemia associated with paraneoplastic syndrome and bone metastases is well known. Meanwhile, the incidence of hypocalcemia is low, except in cases associated with bone-modifying agents used for bone metastases. Hypocalcemia induced by bone-modifying agents typically occurs early after the initial administration, and its incidence can be significantly reduced by preventive administration of calcium and vitamin D3 supplements.

CASE REPORT

We report two cases of recurrent severe hypocalcemia occurring during chemotherapy for metastatic breast cancer with multiple bone metastases. Case 1: A 35-year-old Japanese woman developed metastases in the bone, liver, and ovaries during postoperative endocrine therapy for invasive lobular carcinoma of the breast. She underwent chemotherapy and treatment with denosumab. She experienced recurrent episodes of severe hypocalcemia subsequent to a change in the chemotherapy regimen. Case 2: A 65-year-old Japanese woman encountered multiple bone metastases after postoperative anti-human epidermal growth factor receptor 2 therapy and during endocrine therapy for invasive ductal carcinoma of the breast. She underwent anti-human epidermal growth factor receptor 2 therapy and treatment with denosumab. She experienced recurrent severe hypocalcemia subsequent to a change in the chemotherapy regimen to letrozole + lapatinib, trastuzumab emtansine, and lapatinib + capecitabine.

CONCLUSIONS

We observed two cases of recurrent severe hypocalcemia in patients with advanced breast cancer and bone metastases after modifications to their therapy regimens. These cases differed from the typical hypocalcemia induced by bone-modifying agents. It is possible that antitumor drugs affect calcium and bone metabolism associated with bone metastases. While these cases are rare, it is crucial for oncologists to be aware of hypocalcemia not only at the initiation of bone-modifying agents but also throughout the entire antitumor therapy, as hypocalcemia can lead to fatal outcomes.

The Current Therapeutic Landscape for Metastatic Prostate Cancer

In 2024, there will be an estimated 1,466,718 cases of prostate cancer (PC) diagnosed globally, of which 299,010 cases are estimated to be from the US. The typical clinical approach for PC involves routine screening, diagnosis, and standard lines of treatment. However, not all patients respond to therapy and are subsequently diagnosed with treatment emergent neuroendocrine prostate cancer (NEPC). There are currently no approved treatments for this form of aggressive PC. In this review, a compilation of the clinical trials regimen to treat late-stage NEPC using novel targets and/or a combination approach is presented. The novel targets assessed include DLL3, EZH2, B7-H3, Aurora-kinase-A (AURKA), receptor tyrosine kinases, PD-L1, and PD-1. Among these, the trials administering drugs Alisertib or Cabozantinib, which target AURKA or receptor tyrosine kinases, respectively, appear to have promising results. The least effective trials appear to be ones that target the immune checkpoint pathways PD-1/PD-L1. Many promising clinical trials are currently in progress. Consequently, the landscape of successful treatment regimens for NEPC is extremely limited. These trial results and the literature on the topic emphasize the need for new preventative measures, diagnostics, disease specific biomarkers, and a thorough clinical understanding of NEPC.

Bone-Modifying Agents in Patients With High-Risk Metastatic Castration-Sensitive Prostate Cancer Treated With Abiraterone Acetate

Importance

The association between the use of bone-modifying agents (BMAs) and the outcomes among patients with metastatic castration-sensitive prostate cancer (mCSPC) treated with abiraterone acetate plus prednisone (AAP) remains unclear.

Objective

To investigate the association between BMA use and the outcomes of patients with mCSPC receiving AAP.

Design, Setting, and Participants

In this cohort study, a post hoc analysis of individual participant data from the LATITUDE trial was performed. The LATITUDE trial, a phase 3 randomized clinical trial, aimed to assess the efficacy of AAP and androgen deprivation therapy (ADT) vs dual-placebo and ADT in patients with high-risk mCSPC (data cutoff, August 15, 2018). Eligible patients had newly diagnosed prostate cancer with metastases and at least 2 of 3 high-risk factors (Gleason score ≥8, presence of ≥3 lesions on bone scan, or presence of measurable visceral metastasis). The trial was conducted at 235 sites in 34 countries. Data for the present study were evaluated from July 18 to September 23, 2023.

Exposures

Use of BMAs was defined as the administration of bisphosphonates and denosumab within 90 days before and after randomization.

Main Outcomes and Measures

The primary outcomes were time to skeletal-related events (SREs) and overall survival (OS). An SRE was defined as a clinical or pathological fracture, spinal cord compression, palliative radiation to bone, or surgery involving bone. Differences in these outcomes were examined using the restricted mean survival time from inverse probability of treatment weighting-adjusted Kaplan-Meier curves, estimated until the last event was observed (longest time observed, 63.9 months). Treatment × covariate interactions were analyzed using weighted Cox proportional hazards regression models for the total cohort.

Results

In the total cohort of 1199 patients (956 [79.7%] younger than 75 years), 597 (49.8%) received AAP and ADT, including 474 (79.4%) younger than 75 years and 384 (64.3%) with more than 10 bone metastases (AAP cohort); 602 (50.2%) were treated with dual placebo and ADT, including 482 (80.1%) younger than 75 years and 377 (62.6%) with more than 10 bone metastases (ADT cohort). In the AAP cohort, 132 patients (22.1%) received BMAs, while in the ADT cohort, 131 (21.8%) did. Zoledronic acid was the most frequently administered BMA in both the AAP (93 [70.5%]) and the ADT (88 [67.2%]) cohorts. During the median follow-up of 51.8 (IQR, 47.2-57.0) months in the AAP cohort, BMA use was associated with a longer time to SRE (difference, 7.8 [95% CI, 4.2-11.3] months) but not with OS (difference, 1.6 [95% CI, -2.5 to 5.8] months). In the ADT cohort, BMA use was associated with both time to SRE (difference, 9.3 [95% CI, 5.2-13.3] months) and OS (difference, 5.5 [95% CI, 3.2-9.8] months). No evidence was found that the outcomes of BMA varied by AAP or ADT (hazard ratio for time to SRE, 0.99 [95% CI, 0.48-2.08]; P = .99 for interaction; hazard ratio for OS, 1.31 [95% CI, 0.88-1.96]; P = .18 for interaction).

Conclusions and Relevance

The findings of this cohort study suggest that use of BMAs was associated with a longer time to SRE in patients with high-risk mCSPC treated with ADT, with or without AAP, suggesting that BMA use might provide benefits to this population.

Real-world progression in the survival of de novo Metastatic prostate cancer over the past decade

BACKGROUND

The impact of evolving treatment strategies for metastatic prostate cancer (mPCa) on real-world survival is not well understood. We analyzed changes in mPCa survival over the past decade and discussed the potential driving factors behind these changes.

METHODS

Our study involved 43,228 mPCa patients (2004-2020) from the SEER database, divided into 4 diagnostic periods. We used a multivariate Cox proportional hazards model to evaluate diagnostic periods' influence on overall mortality (OM) and prostate cancer-specific mortality (PSM), and calculated relative median survival improvements between adjacent periods. Subgroup analyses based on age and distant metastasis sites were conducted.

RESULTS

Patients diagnosed in 2016 to 2020 experienced significantly reduced mortality risk compared to those in 2004 to 2007 (HR 0.64 for OM, HR 0.62 for CSM, both P < 0.001). The study period witnessed an absolute improvement in median overall survival (OS) and prostate cancer-specific survival (PCSS), 17 months (54.8%) and 25 months (67.6%) respectively. The most rapid relative survival improvement occurred post-2016, with a 29.7% increase in median OS and a 37.8% increase in PCSS compared to 2012 to 2015. There was a significant reduction in mortality risk throughout the study period in both age groups (age <75 and ≥75), but absolute survival gains were smaller in the older group (24 months [68.6%] vs. 8 months [32%] for OS, 36 months [90.0%] vs. 11 months [33.3%] for PCSS), with lower relative survival improvements after 2016 (37.2% vs. 17.9% for OS, 49% vs. 22.2% for PCSS). All metastasis site subgroups (except M1a) exhibited a significant reduction in mortality risk (all P < 0.001). Absolute survival improvements were 58 months (134.9%) for M1a, 16 months (50.0%) for M1b, and 17 months (54.8%) for M1c.

CONCLUSION

The survival of mPCa have significantly improved over the past decade, although the progress is slower in elderly patients. Investigating the underlying reasons for survival differences among various patient profiles can further refine mPCa treatment strategies.

Prevention of Skeletal-Related Events With Extended-Interval Denosumab: A Review of the Literature

OBJECTIVE

To review published clinical trial data related to efficacy and safety of administering denosumab at extended dosing intervals for prevention of skeletal-related events (SREs) in cancer patients.

DATA SOURCES

A literature search of PubMed was performed (January 2006 to February 2023) using the following search terms: denosumab, bone metastasis, bone lesions, and lytic lesions. Abstracts from conferences, article bibliographies, and product monographs were also reviewed.

STUDY SELECTION AND DATA EXTRACTION

Relevant English-language studies were considered.

DATA SYNTHESIS

Early phase II denosumab trials included treatment arms that utilized extended-interval denosumab, and various retrospective reviews, meta-analyses, and prospective trials have included extended-interval regimens. Most recently, the ongoing randomized REDUSE trial is comparing the efficacy and safety of extended-interval denosumab to standard dosing. At this time, the best available data are restricted to small, randomized trials not designed to compare efficacy and safety of extended-interval denosumab to conventional dosing and did not use consistent endpoints. Furthermore, primary endpoints of available trials largely consisted of surrogate markers of efficacy that may not be reflective of clinical outcomes.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Historically, denosumab has been dosed at 4-week intervals for prevention of SREs. If efficacy is maintained, extending the dosing interval could potentially reduce toxicity, drug cost, and clinic visits compared to every 4-week dosing.

CONCLUSIONS

At this time, data demonstrating efficacy and safety of extended-interval denosumab remain limited, and the results of the REDUSE trial are eagerly anticipated to help answer remaining questions.

Physician knowledge, practice patterns, and barriers encountered regarding guideline-concordant use of bone modifying agents for prostate cancer

BACKGROUND

Guidelines recommend bone-modifying agents (BMAs) for patients with castrate-resistant prostate cancer (CRPC) and bone metastasis, but not for castrate-sensitive prostate cancer (CSPC). Physicians beliefs and practices regarding BMA therapy are poorly understood.

METHODS

This was a qualitative interview study with embedded Likert-scale elements. Study participants were physicians who treat prostate cancer, located within an academic cancer center or an affiliated community-based network. Participants were asked about their experiences and practice patterns regarding BMA therapy. Participants used Likert-scale items to identify the most common barriers to guideline-concordant BMA use and the most effective potential interventions. Participants were subsequently asked to rank the three most common barriers and the three most effective interventions to reduce underuse (for CRPC) and overuse (for CSPC).

RESULTS

Nineteen physicians were invited and 15 participated; one physician did not answer some questions as outside of their practice scope. All were aware of the recommendation for BMAs in CRPC. 14% (2/14) were unaware of the recommendation against BMA use for CSPC; an additional 29% (4/14) believed that BMA use could be appropriate for CSPC depending on the metastatic disease burden. 36% (5/14) were unaware of recommendations for screening and treatment of low bone mineral density. The most common barriers (occurring "often" or "sometimes") were obtaining dental clearance (11/15) and insufficient clinic time (6/15). The interventions identified as most effective to reduce underuse were dental navigation (11/15) and electronic medical record (EMR)-based guidance (9/15). The interventions identified as most effective to reduce overuse were peer-to-peer education (14/15) and EMR-based guidance (13/15).

CONCLUSIONS

Awareness of guideline recommendations for screening and treatment of low bone mineral density and against BMA use for CSPC was good, but not complete. Dental navigation, peer-to-peer education, and EMR-based guidance were preferred intervention strategies to improve guideline-concordant use.

GDF15 Modulates the Zoledronic-Acid-Induced Hyperinflammatory Mechanoresponse of Periodontal Ligament Fibroblasts

Orthodontic tooth movement (OTM) is thought to be impeded by bisphosphonate (BP) therapy, mainly due to increased osteoclast apoptosis and changes in the periodontal ligament (PdL), a connecting tissue between the alveolar bone and teeth. PdL cells, mainly fibroblasts (PdLFs), are crucial regulators in OTM by modulating force-induced local inflammatory processes. Recently, we identified the TGF-β/BMP superfamily member GDF15 as an important modulator in OTM, promoting the pro-inflammatory mechanoresponses of PdLFs. The precise impact of the highly potent BP zoledronate (ZOL) on the mechanofunctionality of PdLFs is still under-investigated. Therefore, the aim of this study was to further characterize the ZOL-induced changes in the initial inflammatory mechanoresponse of human PdLFs (hPdLFs) and to further clarify a potential interrelationship with GDF15 signaling. Thus, two-day in vitro treatment with 0.5 µM, 5 µM and 50 µM of ZOL altered the cellular properties of hPdLFs partially in a concentration-dependent manner. In particular, exposure to ZOL decreased their metabolic activity, the proliferation rate, detected using Ki-67 immunofluorescent staining, and survival, analyzed using trypan blue. An increasing occurrence of DNA strand breaks was observed using TUNEL and an activated DNA damage response was demonstrated using H2A.X (phosphoS139) staining. While the osteogenic differentiation of hPdLFs was unaffected by ZOL, increased cellular senescence was observed using enhanced p21Waf1/Cip1/Sdi1 and β-galactosidase staining. In addition, cytokine-encoding genes such as IL6, IL8, COX2 and GDF15, which are associated with a senescence-associated secretory phenotype, were up-regulated by ZOL. Subsequently, this change in the hPdLF phenotype promoted a hyperinflammatory response to applied compressive forces with an increased expression of the pro-inflammatory markers IL1β, IL6 and GDF15, as well as the activation of monocytic THP1 cells. GDF15 appeared to be particularly relevant to these changes, as siRNA-mediated down-regulation balanced these hyperinflammatory responses by reducing IL-1β and IL-6 expression (IL1B p-value < 0.0001; IL6 p-value < 0.001) and secretion (IL-1β p-value < 0.05; IL-6 p-value < 0.001), as well as immune cell activation (p-value < 0.0001). In addition, ZOL-related reduced RANKL/OPG values and inhibited osteoclast activation were enhanced in GDF15-deficient hPdLFs (both p-values < 0.0001; all statistical tests: one-way ANOVA, Tukey's post hoc test). Thus, GDF15 may become a promising new target in the personalized orthodontic treatment of bisphosphonatepatients.

Beyond boundaries: unraveling innovative approaches to combat bone-metastatic cancers

Evidence demonstrated that bones, liver, and lungs are the most common metastasis sites in some human malignancies, especially in prostate and breast cancers. Bone is the third most frequent target for spreading tumor cells among these organs and tissues. Patients with bone-metastatic cancers face a grim prognosis characterized by short median survival time. Current treatments have proven insufficient, as they can only inhibit metastasis or tumor progression within the bone tissues rather than providing a curative solution. Gaining a more profound comprehension of the interplay between tumor cells and the bone microenvironment (BME) is of utmost importance in tackling this issue. This knowledge will pave the way for developing innovative diagnostic and therapeutic approaches. This review summarizes the mechanisms underlying bone metastasis and discusses the clinical aspects of this pathologic condition. Additionally, it highlights emerging therapeutic interventions aimed at enhancing the quality of life for patients affected by bone-metastatic cancers. By synthesizing current research, this review seeks to shed light on the complexities of bone metastasis and offer insights for future advancements in patient care.

Bone-targeting agents in major solid tumour metastases: a multinational cohort study

OBJECTIVE

To describe the epidemiology, clinical characteristics and utilisation patterns of bone-targeting agents (BTAs) in patients with bone metastases from breast, prostate and lung cancer.

METHODS

This is a multinational retrospective cohort study including patients with three major solid tumours (breast, prostate and lung cancer) and newly initiated on BTAs (ie, denosumab, zoledronic acid and pamidronate). Records were retrieved from nationwide health databases from Hong Kong and Taiwan (HK and TW: 2013-2017) and Korea (KR: 2012-2016). Descriptive analyses included the annual incidence rates of bone metastases and the cumulative incidence curves of BTA initiation. We used Sankey diagrams to visualise the dynamic BTA utilisation patterns.

RESULTS

The annual incidence rate of bone metastases ranged from 3.5% to 4.5% in TW, from 9.6% to 10.3% in HK and from 2.9% to 3.8% in KR. We identified 14.1% (5127), 9.3% (883) and 9.4% (4800) of patients with bone metastases newly initiated on BTAs in TW, HK and KR, respectively. The most frequently used BTA in TW (67.1%) and HK (51.9%) was denosumab, while in KR (84.8%) it was zoledronic acid. Sankey diagrams indicated the proportion of patients remaining on denosumab was highest in TW and HK, while it was zoledronic acid in KR. Specifically, in TW, patients who were on bisphosphonates or had discontinued treatment frequently switched to or reinitiated denosumab.

CONCLUSIONS

We found the rate of BTA utilisation remained low across all sites and tumour types in recent years. The dynamic utilisation patterns of BTAs provide better understanding of the treatment landscape for future evaluation of associated outcomes of patients.

Determinants of Bone-Modifying Agent Prescribing for Metastatic Castration-Resistant Prostate Cancer in a National Health Care Delivery System

PURPOSE

Despite guidelines recommending bone-modifying agents (BMAs) to decrease skeletal-related events (SREs) in men with metastatic castration-resistant prostate cancer (mCRPC), BMAs are underutilized. In this retrospective cohort study, we report the factors associated with BMA use in a national health care delivery system.

METHODS

We used the Veterans Affairs Corporate Data Warehouse to identify men with mCRPC between 2010 and 2017. BMA prescribing frequency was evaluated, and the association between patient- and disease-specific factors with BMA use was assessed using multivariable logistic regression.

RESULTS

Among 3,980 men identified with mCRPC (mean age 73.5 years, 29% Black), 47% received a BMA; median time to BMA from start of mCRPC treatment was 102 days. Factors associated with BMA use included previous BMA use (adjusted odds ratio [aOR], 7.81 [95% CI, 6.48 to 9.47]), diagnosis code for bone metastases (aOR, 1.26 [95% CI, 1.08 to 1.46]), and concomitant corticosteroid use (aOR, 1.53 [95% CI, 1.29 to 1.82]). Decreased BMA use was associated with advancing age (aOR, 0.85 per 10 years [95% CI, 0.78 to 0.92]), Charlson comorbidity index ≥2 (aOR, 0.76 [95% CI, 0.63 to 0.93]), Black race (aOR, 0.83 [95% CI, 0.70 to 0.98]), and decreased estimated glomerular filtration rate (eGFR; aOR, 0.19 [95% CI, 0.11 to 0.32] for eGFR 0-29 mL/minutes; aOR, 0.76 [95% CI, 0.64 to 0.91] for 30-59 mL/minutes).

CONCLUSION

Patients who are older, Black, or have more comorbidities are less likely to receive guideline concordant care to prevent SREs. These observations highlight the unique challenges of caring for patients with mCRPC and the need for future studies to increase BMA use in these populations.

Clinical Impact on Dental Implant Survival in Patients Taking Antiresorptive Medications: A Systematic Review and Meta-Analysis

Dental implants are a predictable option to replace missing teeth. Patients on antiresorptive medications used to treat disorders associated with bone resorption may need dental implants to replace missing teeth. The data on implant failure in patients on antiresorptive medication requiring dental implants, is conflicting and limited. This systematic review aims to investigate if antiresorptive medications have any clinical impact on dental implant survival. Electronic databases were searched until May 2020. The focus question (PICOS): Participants: humans, Interventions: implant placement surgery in patients on antiresorptive medication, Comparisons: patients on antiresorptive medication vs control (patients not on antiresorptive medication), Outcomes: implant survival, and Study design: clinical studies. The protocol of this systematic review was registered in PROSPERO (CRD42020209083). Fourteen nonrandomized studies were selected for data extraction and risk of bias assessment using the ROBINS-1 tool. Only studies with a control were included for the meta-analysis, 8 articles were included in the meta-analysis using implant-level data, and 5 articles were included in the meta-analysis using patient-level data. There was no statistical significance between the 2 groups at the patient level based on 265 patients. However, there was a statistically significant difference at the implant level based on 2697 implants. Therefore, antiresorptive medications, mainly bisphosphonates (BPs), may significantly contribute to implant failure. Antiresorptive medications, especially BPs may reduce implant survival and impair the osseointegration of dental implants. Failed implants in patients on BPs may not lead to osteonecrosis and may be replaced with success.

Clinical Outcomes of Switching from Zoledronic Acid to Denosumab for the Management of Severe Bone Metastasis from Hepatocellular Carcinoma: A Single-Center, Open-Label, Prospective Intervention Trial

Background

Zoledronic acid reduces the risk of bone metastasis, but denosumab is a better option for treating bone metastases. However, few studies have evaluated the use of denosumab to treat bone metastasis originating from hepatocellular carcinoma. This study aimed to assess the clinical outcomes of switching from zoledronic acid to denosumab for treating bone metastasis in patients with hepatocellular carcinoma.

Methods

This prospective study enrolled 10 patients with HCC and bone metastases. The levels of type 1 collagen cross-linked N-telopeptide (NTx) and tumor growth remained abnormal in these patients despite administration of zoledronic acid for over 3 months. We switched from zoledronic acid to 120 mg denosumab every 4 weeks and evaluated the clinical outcomes, including changes in the NTx level, pain level, and activities of daily living, as well as adverse events, after each administration.

Results

Urinary NTx clearance was normal in all patients. The average urinary NTx clearance increased from 13.2 to 21.2 nmol BCE/nmol · Cre (P = 0.54) after the switch to denosumab. Serum NTx levels were abnormal in all cases. The serum NTx level decreased from 142 nmol BCE/L to 126 nmol BCE/L (P = 0.56). The answers to questionnaires on pain and activities of daily living did not change significantly. Some patients showed elevated transaminase levels, but this was not due to the drug switch.

Conclusion

Switching to denosumab did not show a significant change of the pain and activity of daily living for the patients with severe bone metastasis from hepatocellular carcinoma, in whom the efficacy of zoledronic acid was limited.

Denosumab for giant cell tumors of bone from 2010 to 2022: a bibliometric analysis

Giant cell tumors of the bone (GCTB) are considered moderately malignant bone tumors. Denosumab, as a neoadjuvant therapy, provides new possibilities for treating GCTB. However, even after multiple studies and long-term clinical trials, there are limitations in the treatment process. Research data and Medical Subject Headings terms related to denosumab and GCTB were collected from January 2010 to October 2022 using the Web of Science and MeSH ( https://meshb.nlm.nih.gov ) browsers. These data were imported into CiteSpace and VOSviewer softwares for bibliometric analysis. Overall, 445 publications on denosumab and GCTB were identified. Over the last 12 years, the growth rate of the total number of publications has remained relatively stable. The USA published the highest number of articles (83) and had the highest centrality (0.42). Amgen Inc. and Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) First Ortoped Rizzoli were identified as the most influential institutions. Many authors have made outstanding contributions to this field. Lancet Oncology had the highest journal impact factor (54.433). Local recurrence and drug dosage are current research hotspots, and future development trends will mainly focus on prognostic markers of GCTB and the development of new therapies. Further research is required to analyze denosumab's safety and efficacy and understand its local recurrence of GCTB, to identify the optimal dose. Future progress in this field will likely focus on exploring new diagnostic and recurrence markers to monitor disease progression and examine new therapeutic targets and treatment strategies.

Bone-modifying agents are protective for symptomatic skeletal events in Radium-223 treatment

INTRODUCTION

Radium-223 (Ra-223) dichloride therapy increases overall survival and delays time to the first symptomatic skeletal event (SSE) in patients with castration-resistant prostate cancer (CRPC) and bone metastases. Bone-modifying agents (BMA) reduce SSE in patients with bone metastasis, but there is little information on their use with Ra-223. This study aimed to investigate the effect of BMA on SSE in patients with bone metastatic CRPC treated with Ra-223 in real-world practice.

METHODS

We included 73 patients treated with Ra-223 from 10 institutions in Japan. Time to the first SSE was estimated using the Kaplan-Meier method and compared between groups using the log-rank test. We used univariate analysis to ascertain the association between variables and SSE.

RESULTS

During a median follow-up of 12.7 months (interquartile range, 7-21.7), 12 (16.4%) patients presented SSE. Age and BMA use were different between men with and without SSE. The 1-year SSE-free survival rate from Ra-223 treatment initiation was 82.4% (95% CI, 69.4%-90.2%). BMA use was associated with favorable SSE-free survival (hazard risk, 0.23; 95% confidence interval, 0.061-0.85; p = 0.027). Two (4.7%) and seven (23.3%) patients presented symptomatic pathological bone fracture in groups with and without BMA use, respectively (p = 0.017).

CONCLUSION

This study stresses the importance of BMA use in patients with CRPC and bone metastases in Ra-223 treatment.

Denosumab administration for bone metastases from solid tumors: a retrospective cross-sectional study

BACKGROUND

Little is known on how denosumab reduces skeletal-related events (SREs) by bone metastases from solid tumors. We sought to evaluate the effect of denosumab administration in patients with bone metastases from solid tumors.

METHODS

Data of patients treated with denosumab were collected from electronic medical charts (n = 496). Eligible participants in this study were adult patients (age ≥ 18 years) with metastatic bone lesions from solid tumors treated with denosumab. SREs, surgical interventions, the spinal instability neoplastic score (SINS) for spinal region, and Mirels' score for the appendicular region were evaluated. To assess whether denosumab could prevent SREs and associated surgery, the SINS and Mirels' score were compared between patients with and without SREs.

RESULTS

A total of 247 patients (median age, 65.5 years old; median follow-up period, 13 months) treated with denosumab for metastatic bone lesions from solid tumors were enrolled in this study. SREs occurred in 19 patients (7.7%). SREs occurred in 2 patients (0.8%) who took denosumab administration before SREs. Surgical interventions were undertaken in 14 patients (5.7%) (spinal and intradural lesions in five patients and appendicular lesions in nine patients). The mean SINS of patients without SREs compared to those with SREs were 7.5 points and 10.2 points, respectively. The mean Mirels' scores of non-SREs patients and those with SREs were 8.07 points and 10.7 points, respectively. Patients with SREs had significantly higher Mirels' score than non-SREs patients (p < 0.01). Patients with SREs had higher SINS than non-SREs patients (p = 0.09).

CONCLUSIONS

SREs occurred in patients with higher SINS or Mirels' scores. Two patients suffered from SREs though they took denosumab administration before SREs. Appropriate management of denosumab for patients with bone metastasis is significant. Surgical interventions may be needed for patients who with higher SINS or Mirel's scores.

Systemic Therapies for Metastatic Castration-Resistant Prostate Cancer: An Updated Review

The introduction of novel therapeutic agents for advanced prostate cancer has led to a wide range of treatment options for patients with metastatic castration-resistant prostate cancer (mCRPC). In the past decade, new treatment options for mCRPC, including abiraterone, enzalutamide, docetaxel, cabazitaxel, sipuleucel-T, radium-223, 177Lu-PSMA-617, and Olaparib, have demonstrated a survival benefit in phase 3 trials. Bone-modifying agents have become part of the overall treatment strategy for mCRPC, in which denosumab and zoledronic acid reduce skeletal-related events. Recently, androgen receptor-signaling inhibitors (ARSIs) and docetaxel have been used upfront against metastatic castration-sensitive prostate cancer. Further, triplet therapy with ARSI, docetaxel, and androgen deprivation therapy is emerging. However, cross-resistance may occur between these treatments, and the optimal treatment sequence must be considered. The sequential administration of ARSIs, such as abiraterone and enzalutamide, is associated with limited efficacy; however, cabazitaxel is effective for patients with mCRPC who were previously treated with docetaxel and had disease progression during treatment with ARSI. Radioligand therapy with 177Lu-PSMA-617 is a new effective class of therapy for patients with advanced PSMA-positive mCRPC. Tumors with gene alterations that affect homologous recombination repair, such as BRCA1 and BRCA2 alterations, are sensitive to poly (adenosine diphosphate-ribose) polymerase (PARP) inhibitors in mCRPC. This review sought to highlight recent advances in systemic therapy for mCRPC and strategies to support patient selection and treatment sequencing.

Risk comparison of osteonecrosis of the jaw in osteoporotic patients treated with bisphosphonates vs. denosumab: a multi-institutional retrospective cohort study in Taiwan

In this multi-institutional retrospective cohort study, we compared the long-term risk of osteonecrosis of the jaw following the use of denosumab vs. bisphosphonates in osteoporotic patients. After 2-year use, the likelihood of osteonecrosis of the jaw is lower with denosumab compared to bisphosphonates, and the difference increases with time.

PURPOSE

To compare the long-term risk of osteonecrosis of the jaw (ONJ) between osteoporotic patients treated with bisphosphonates (BPs) and denosumab.

METHODS

This multi-institutional retrospective cohort study included patients aged > 40 years with osteoporosis between January 2010 and December 2018. Patients who met the eligibility criteria were divided into BPs and denosumab groups by propensity score matching (PSM). The risk of ONJ of denosumab vs. BPs was estimated using a Cox proportional hazards model and was described by the cumulative incidence rate using the Kaplan-Meier method.

RESULTS

A total of 84,102 patients with osteoporosis were enrolled, among whom, 8962 were eligible for inclusion based on their first-line drug use (denosumab, n = 3,823; BPs, n = 5,139). Following PCM matching (1:1), the BPs and denosumab groups included 3665 patients each. The incidence density of ONJ in the denosumab and BPs matching groups was 1.47 vs. 2.49 events (per 1000 person-years), respectively. The hazard ratio of ONJ in the denosumab vs. BPs group was estimated as 0.581 (95% confidence interval: 0.33-1.04, p = 0.07). The cumulative incidence rates of ONJ in both groups were similar for the first and second years of drug use (p = 0.062), but significantly different from the third year onwards (p = 0.022). The severity of ONJ was not significantly different between the two groups.

CONCLUSION

In osteoporotic patients, after 2 years of use, the likelihood of ONJ being induced by denosumab is lower than that of BPs, and the difference increases with time.

Recent advances and future perspectives in the therapeutics of prostate cancer

Prostate cancer (PC) is one of the most common cancers in males and the fifth leading reason of death. Age, ethnicity, family history, and genetic defects are major factors that determine the aggressiveness and lethality of PC. The African population is at the highest risk of developing high-grade PC. It can be challenging to distinguish between low-risk and high-risk patients due to the slow progression of PC. Prostate-specific antigen (PSA) is a revolutionary discovery for the identification of PC. However, it has led to an increase in over diagnosis and over treatment of PC in the past few decades. Even if modifications are made to the standard PSA testing, the specificity has not been found to be significant. Our understanding of PC genetics and proteomics has improved due to advances in different fields. New serum, urine, and tissue biomarkers, such as PC antigen 3 (PCA3), have led to various new diagnostic tests, such as the prostate health index, 4K score, and PCA3. These tests significantly reduce the number of unnecessary and repeat biopsies performed. Chemotherapy, radiotherapy, and prostatectomy are standard treatment options. However, newer novel hormone therapy drugs with a better response have been identified. Androgen deprivation and hormonal therapy are evolving as new and better options for managing hormone-sensitive and castration-resistant PC. This review aimed to highlight and discuss epidemiology, various risk factors, and developments in PC diagnosis and treatment regimens.

Jaw Bone Invasion of Oral Squamous Cell Carcinoma Is Associated with Osteoclast Count and Expression of Its Regulating Proteins in Patients and Organoids

AIMS

Oral squamous cell carcinoma (OSCC) frequently invades the jaw. The exact mechanism of bone invasion remains unclear. This study investigates (premature) osteoclasts and the expression of its differentiation regulating proteins RANKL, OPG and RANK in patients with OSCC.

METHODS

Resection specimens from OSCC patients were divided into NI group (No Invasion), E group (Erosion) or I group (bone Invasion). Tissue sections were stained with Cathepsin K (osteoclast-counting), RANKL, OPG and RANK. The staining intensity was scored on different regions of the tumor: front, center, back and normal mucosa. Immunohistochemistry and qPCR for RANKL/OPG/RANK were performed on five head and neck squamous cell carcinoma (HNSCC) organoids.

RESULTS

The mean number of osteoclasts (I group) and premature osteoclasts (E group) was significantly higher compared to the NI group (p = 0.003, p = 0.036). RANKL expression was significantly higher in the tumor front and tumor center compared to normal mucosa (all groups). In the I group, RANKL and RANK expression was significantly higher in the tumor front compared to the tumor back and there was a trend of higher RANKL expression in the tumor front compared to the E group and NI group. qPCR showed a 20-43 times higher RANKL mRNA expression in three out of five tumor organoids compared to a normal squamous cell organoid line. There was no correlation between protein and mRNA expression in the HNSCC organoids.

CONCLUSIONS

These findings suggest that OSCCs induce bone invasion by stimulating osteoclast activation by regulating the production of RANKL and RANK proteins.

A Facile Crystallization Strategy to Turn Calcium Bisphosphonates into Novel Osteogenesis-Inducing Biomaterials

Insoluble metal bisphosphonates (BPs) are considered an ideal alternative to the soluble counterparts in regenerative medicine due to their increased BP release profile, but still present undesired properties (e.g., low stability, uncontrolled degradation, and poor biocompatibility). Through a simple crystallization on a solid calcium hydroxyapatite (HA)-based substrate from a BP precursor solution in 30 days, a series of insoluble calcium BP (CaBP) crystals are developed. These crystals, including calcium alendronate (CaAln), calcium pamidronate (CaPam), calcium incadronate (CaInc), calcium risedronate (CaRis), calcium zoledronate (CaZol), and calcium di-minodronate (Ca(Min)2 ), present high purity, regular morphologies and excellent biodegradability. It is demonstrated that these CaBPs can induce osteogenic differentiation of adipose-derived mesenchymal stem cells in vitro in the absence of other osteogenic inducers. It is further found that CaBP induces bone formation more effectively in a femur defect rabbit model in three months but with a lower in vivo hematotoxicity than the clinically used HA during osteogenesis. It is believed that these desired biological properties arise from the capability of the insoluble CaBPs in releasing BPs in a sustained manner for stimulating osteogenesis. This work provides a significant strategy for turning CaBPs into novel biomaterials for tissue regeneration and demonstrates their great potential in the clinic.

RANK pathway in cancer: underlying resistance and therapeutic approaches

Cancer remains one of the deadliest diseases despite advances in treatment. Metastatic cancers are the leading cause of death for advanced cancer patients. Those with advanced cancer with osteolytic-type bone metastases have a significantly lower quality of life. A novel treatment plan is needed now more than ever for breast cancer patients with bone metastases. There are shreds of evidence that cancer cells in the bloodstream interact with the bone microenvironment and that this interaction is a contributing component to breast cancer progression. Preventing any stage of this cycle can result in anti-metastasis effects. Since RANKL interacts with its receptor RANK and plays an important role in the vicious cycle, it has proven to be a successful therapeutic target in cancer treatment. As a result, we have presented a complete overview of the RANK pathway in cancer and discussed RANK signaling and tumor microenvironment, and potential therapeutic approaches in this review.

Severe hypocalcemia after denosumab treatment leading to refractory ventricular tachycardia and veno-arterial extracorporeal membrane oxygenation support: a case report

BACKGROUND

Severe hypocalcemia may lead to life-threatening arrhythmias. Denosumab is an effective treatment for osteoporosis that allows long intervals between doses. However, there is a risk of hypocalcemia in some patients. Due to the long half-life of denosumab, emergency physicians caring for patients presenting with symptoms of hypocalcemia may not be aware of the medication, and adverse effects may last longer.

CASE PRESENTATION

A 55-year-old woman with a history of systemic lupus erythematosus (SLE) and anxiety disorder called for an ambulance for symptoms of hyperventilation and muscle cramps. After evaluation at the local hospital, she developed pulseless ventricular tachycardia and was resuscitated by defibrillation by the hospital staff. After conversion to sinus rhythm, she was transported to a tertiary center. Upon arrival, pulseless ventricular tachycardia occurred again, and veno-arterial extracorporeal membrane oxygenation (ECMO) and intra-aortic balloon pumping (IABP) were implemented. Laboratory results showed severe hypocalcemia (corrected calcium level of 5.3 mg/dL) whereupon intravenous calcium supplementation was started. She had received the first dose of denosumab (60 mg) by subcutaneous injection 24 days prior to hospitalization. She was eventually weaned from ECMO and IABP support.

CONCLUSION

Cardiac arrest due to hypocalcemia is relatively rare but can be fatal. In the present case, hyperventilation may have acutely exacerbated pre-existing hypocalcemia, leading to ventricular tachycardia. The patient had a slightly decreased serum calcium level prior to denosumab. Close monitoring may be preferable after the primary dose of denosumab in selected patients. Emergency physicians caring for patients who may be suffering from symptoms/signs of hypocalcemia must be mindful of medications that have long half-lives and affect electrolyte balance when treating fatal arrhythmia due to hypocalcemia.

Prevalence and Prognostic Implications of PSA Flares during Radium-223 Treatment among Men with Metastatic Castration Resistant Prostate Cancer

Radium-223 (Ra233) prolongs the survival of men with symptomatic bone-predominant metastatic castration-resistant prostate cancer (mCRPC). However, prostate-specific antigen (PSA) response patterns are not closely associated with Ra223 therapy outcomes. Herein, we sought to analyze the impact of Ra223-induced PSA flares on patient outcome. Using a retrospective cohort study of Ra223 treatment in four Ontario/Canada cancer centres, we identified 134 patients grouped into sub-cohorts according to distinct PSA response patterns: (i) initial PSA flare followed by eventual PSA decline; (ii) PSA response (≥30% PSA decrease within 12 weeks of treatment); and (iii) PSA non-response. We analyzed patient characteristics and outcome measures, including overall survival (OS), using the Kaplan-Meier method and log-rank testing. PSA flares were observed in 27 (20.2%), PSA responses in 11 (8.2%), and PSA non-responses in 96 (71.6%) patients. Amongst PSA flare patients, 12 presented with post-flare PSA decreases below baseline and 15 with PSA decreases below the flare peak but above baseline. Although only six flare patients achieved ≥30% PSA decreases below baseline, the median OS of all flare patients (16.8 months, 95% CI 14.9-18.7) was comparable to that of PSA responders and non-responders (p = 0.349). In summary, around 20% of mCRPC patients experience Ra223-induced PSA flares, whose outcome is similar to that of men with or without PSA responses. Further studies are needed regarding suitable biochemical surrogate markers of response to Ra223.

Zoledronic Acid Prevents Bone Resorption Caused by the Combination of Radium-223, Abiraterone Acetate, and Prednisone in an Intratibial Prostate Cancer Mouse Model

An increased risk of non-pathological fractures in patients with prostate cancer and bone metastases has been associated with combination treatment with radium-223, abiraterone, and prednisone/prednisolone in the absence of bone-protecting agents. Here, we investigated possible mechanisms leading to this outcome using an intratibial LNCaP model mimicking prostate cancer bone metastases. Male NOD.scid mice were inoculated intratibially with LNCaP prostate cancer cells and treated with vehicle, radium-223, abiraterone, prednisone, zoledronic acid, or their combinations for 28 days. Serum TRACP 5b and PSA levels were measured. Bone structure, quality, and formation rate of non-tumor-bearing and tumor-bearing tibiae were analyzed by microCT, 3-point bending assay, and dynamic histomorphometry, respectively. Radium-223 incorporation into bone was also measured. Radium-223/abiraterone/prednisone combination treatment induced a transient increase in bone resorption indicated by elevated TRACP 5b levels, which was inhibited by concurrent treatment with zoledronic acid. Furthermore, radium-223/abiraterone/prednisone combination reduced periosteal and trabecular new bone formation and the number of osteoblasts, but bone structure or biomechanical quality were not affected. The abiraterone/prednisone treatment decreased radium-223 incorporation into tumor-bearing bone, possibly explaining the lack of additional antitumor efficacy. In conclusion, radium-223/abiraterone/prednisone combination increased bone resorption, which may have been one of the mechanisms leading to an increased fracture risk in patients with mCRPC.

Sarcopenia in Men With Bone-Predominant Metastatic Castration-Resistant Prostate Cancer Undergoing Ra-223 Therapy

INTRODUCTION

Osteosarcopenia is the progressive loss of musculoskeletal structure and functionality, contributing to disability and mortality. Despite complex interactions between bone and muscle, osteosarcopenia prevention and treatment in men with metastatic castration-resistant prostate cancer (mCRPC) focuses predominantly on bone health. It is unknown whether Radium-223 (Ra-223) therapy affects sarcopenia.

METHODS

We identified 52 patients with mCRPC who had received Ra-223 and had a baseline plus ≥1 follow-up abdominopelvic CT scan. The total contour area (TCA) and averaged Hounsfield units (HU) of the left and right psoas muscles were obtained at the inferior L3 endplate, and the psoas muscle index (PMI) was calculated therefrom. Intrapatient musculoskeletal changes were analyzed across various time points.

RESULTS

TCA and PMI gradually declined over the study period (P = .002, P = .003, respectively), but Ra-223 therapy did not accelerate sarcopenia, nor the decline of HU compared to the pre-Ra-223 period. The median overall survival of patients with baseline sarcopenia was numerically worse (14.93 vs. 23.23 months, HR 0.612, P = .198).

CONCLUSIONS

Ra-223 does not accelerate sarcopenia. Thus, worsening muscle parameters in men with mCRPC undergoing Ra-223 therapy are attributable to other factors. Further research is needed to determine whether baseline sarcopenia predicts poor overall survival in such patients.

Prevalence of Precursory Signs of Atypical Femoral Fractures in Patients Receiving Bone-Modifying Agents for Bone Metastases: A Cross-Sectional Study

Patients on bone-modifying agents (BMAs) for bone metastases are at risk of atypical femoral fractures (AFFs), which can lead to a sudden deterioration in performance status. In this study, we sought to determine the prevalence of radiographic precursory signs of AFF in patients on oncologic BMAs. Forty-two patients (23 men, 19 women; mean age 68.8 ± 10.0 years) on oncologic BMAs (zoledronate for >3 years and/or denosumab for >1 year) and without clinical symptoms were enrolled between 2019 and 2021. All patients were receiving denosumab at enrollment and 5 had previously used zoledronate. The mean duration of BMA use was 31.2 ± 18.5 months. Radiographs of both femurs were screened for precursory signs of AFF (e.g., thickening of the lateral cortex). The patients were divided into two groups according to thickening status and compared by duration of BMA use. They were also divided into three groups by duration of BMA use (12-23 months, n = 18; 24-59 months, n = 19; ≥60 months, n = 5), and the prevalence of apparent thickenings was examined. As a result, 18 patients (42.9%) showed minute local or diffuse thickening and 10 (23.8%) showed apparent local thickening. The duration of BMA use was significantly longer in patients with apparent thickening than in those without (47.3 ± 23.6 months [n = 10] versus 26.2 ± 13.5 months [n = 32]; p < 0.05). The prevalence of apparent thickening increased with increasing duration of BMA use (12-23 months, 5.6%; 24-59 months, 31.6%; ≥60 months, 60.0%). In conclusion, radiographic precursory signs of AFF are common in patients on oncologic BMAs. Radiographic screening for AFF could be relevant in patients who have been on long-term oncologic BMAs, even if asymptomatic. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

A Comprehensive Review of Interventional Clinical Trials in Patients with Bone Metastases

Bone metastasis is one of the most important factors associated with poor prognosis for patients with prostate, breast, thyroid, and lung cancer. In the past two decades, 651 clinical trials, including 554 interventional trials, were being registered in ClinicalTrials.gov and pharma.id.informa.com to combat bone metastases from different perspectives. In this review, we comprehensively analyzed, regrouped, and discussed all the interventional trials on bone metastases. Clinical trials were re-grouped into bone-targeting agents, radiotherapy, small molecule targeted therapy, combination therapy, and others, based on the different mechanisms of action including modifying the bone microenvironment and preventing the growth of cancer cells. We also discussed the potential strategies that might improve overall survival and progression-free survival of patients with bone metastases in the future.

Metastatic Castration-Resistant Prostate Cancer: Insights on Current Therapy and Promising Experimental Drugs

The therapeutic landscape of metastatic hormone sensitive and metastatic castration-resistant prostate cancer (mCRPC) is rapidly changing. We reviewed the current treatment options for mCRPC, with insights on new available therapeutic strategies. Chemotherapy with docetaxel or cabazitaxel (for patients progressing on docetaxel), as well as treatment with androgen receptor axis targeted therapies, and Radium-223 are well-established treatment options for patients with mCRPC. The advent of theragnostic in prostate cancer established Lutetium-177 (177Lu)-PSMA-617 as a new standard of care for PSMA-positive mCRPC previously treated with ARAT and taxane-based chemotherapy. Olaparib, a poly-ADP-ribose polymerase (PARP) inhibitor, is approved for selected patients with mCRPC progressed on ARATs and in combination with abiraterone acetate as first-line treatment for mCRPC. Immunotherapy showed limited efficacy in unselected patients with mCRPC and novel immunotherapy strategies need to be explored. The search for biomarkers is a growing field of interest in mCRPC, and predictive biomarkers are needed to support the choice of treatment and the development of tailored strategies.

Factors Associated with Long-Term Prostate Cancer Survival after Palliative Radiotherapy to a Bone Metastasis and Contemporary Palliative Systemic Therapy: A Retrospective, Population-Based Study

BACKGROUND

Radiation therapy (RT) is an established palliative treatment for bone metastases; however, little is known about post-radiation survival and factors which impact it. The aim of this study was to assess a population-based sample of metastatic prostate cancer patients receiving palliative radiation therapy to bone metastases and contemporary palliative systemic therapy and identify factors that impact long-term survival.

MATERIALS/METHODS

This retrospective, population-based, cohort study assessed all prostate cancer patients receiving palliative RT for bone metastases at a Canadian provincial Cancer program during a contemporary time period. Baseline patient, disease, and treatment characteristics were extracted from the provincial medical physics databases and the electronic medical record. Post-RT Survival intervals were defined as the time interval from the first fraction of palliative RT to death from any cause or date of the last known follow-up. The median survival of the cohort was used to dichotomize the cohort into short- and long-term survivors following RT. Univariable and multivariable hazard regression analyses were performed to identify variables associated with post-RT survival.

RESULTS

From 1 January 2018 until 31 December 2019, 545 palliative RT courses for bone metastases were delivered to n = 274 metastatic prostate cancer patients with a median age of 76 yrs (Interquartile range (IQR) 39-83) and a median follow-up of 10.6 months (range 0.2 to 47.9). The median survival of the cohort was 10.6 months (IQR 3.5-25 months). The ECOG performance status of the whole cohort was ≤2 in n = 200 (73%) and 3-4 in n = 67 (24.5%). The most commonly treated sites of bone metastasis were the pelvis and lower extremities n = 130 (47.4%), skull and spine n = 114 (41.6%), and chest and upper extremities n = 30 (10.9%). Most patients had CHAARTED high volume disease n = 239 (87.2%). On multivariable hazard regression analysis, an ECOG performance status of 3-4 (p = 0.02), CHAARTED high volume disease burden (p = 0.023), and non-receipt of systemic therapy (p = 0.006) were significantly associated with worse post-RT survival.

CONCLUSION

Amongst metastatic prostate cancer patients treated with palliative radiotherapy to bone metastases and modern palliative systemic therapies, ECOG performance status, CHAARTED metastatic disease burden, and type of first-line palliative systemic therapy were significantly associated with post-RT survival durations.

Health-related quality of life and pain outcomes with [177Lu]Lu-PSMA-617 plus standard of care versus standard of care in patients with metastatic castration-resistant prostate cancer (VISION): a multicentre, open-label, randomised, phase 3 trial

BACKGROUND

In VISION, the prostate-specific membrane antigen (PSMA)-targeted radioligand therapy lutetium-177 [177Lu]Lu-PSMA-617 (vipivotide tetraxetan) improved radiographic progression-free survival and overall survival when added to protocol-permitted standard of care in patients with metastatic castration-resistant prostate cancer. Here, we report additional health-related quality of life (HRQOL), pain, and symptomatic skeletal event results.

METHODS

This multicentre, open-label, randomised, phase 3 trial was conducted at 84 cancer centres in nine countries in North America and Europe. Eligible patients were aged 18 years or older; had progressive PSMA-positive metastatic castration-resistant prostate cancer; an Eastern Cooperative Oncology Group (ECOG) performance status score of 0-2; and had previously received of at least one androgen receptor pathway inhibitor and one or two taxane-containing regimens. Patients were randomly assigned (2:1) to receive either [177Lu]Lu-PSMA-617 plus protocol-permitted standard of care ([177Lu]Lu-PSMA-617 group) or standard of care alone (control group) using permuted blocks. Randomisation was stratified by baseline lactate dehydrogenase concentration, liver metastases, ECOG performance status, and androgen receptor pathway inhibitor inclusion in standard of care. Patients in the [177Lu]Lu-PSMA-617 group received intravenous infusions of 7·4 gigabecquerel (GBq; 200 millicurie [mCi]) [177Lu]Lu-PSMA-617 every 6 weeks for four cycles plus two optional additional cycles. Standard of care included approved hormonal treatments, bisphosphonates, and radiotherapy. The alternate primary endpoints were radiographic progression-free survival and overall survival, which have been reported. Here we report the key secondary endpoint of time to first symptomatic skeletal event, and other secondary endpoints of HRQOL assessed with the Functional Assessment of Cancer Therapy-Prostate (FACT-P) and EQ-5D-5L, and pain assessed with the Brief Pain Inventory-Short Form (BPI-SF). Patient-reported outcomes and symptomatic skeletal events were analysed in all patients who were randomly assigned after implementation of measures designed to reduce the dropout rate in the control group (on or after March 5, 2019), and safety was analysed according to treatment received in all patients who received at least one dose of treatment. This trial is registered with ClinicalTrials.gov, NCT03511664, and is active but not recruiting.

FINDINGS

Between June 4, 2018, and Oct 23, 2019, 831 patients were enrolled, of whom 581 were randomly assigned to the [177Lu]Lu-PSMA-617 group (n=385) or control group (n=196) on or after March 5, 2019, and were included in analyses of HRQOL, pain, and time to first symptomatic skeletal event. The median age of patients was 71 years (IQR 65-75) in the [177Lu]Lu-PSMA-617 group and 72·0 years (66-76) in the control group. Median time to first symptomatic skeletal event or death was 11·5 months (95% CI 10·3-13·2) in the [177Lu]Lu-PSMA-617 group and 6·8 months (5·2-8·5) in the control group (hazard ratio [HR] 0·50, 95% CI 0·40-0·62). Time to worsening was delayed in the [177Lu]Lu-PSMA-617 group versus the control group for FACT-P score (HR 0·54, 0·45-0·66) and subdomains, BPI-SF pain intensity score (0·52, 0·42-0·63), and EQ-5D-5L utility score (0·65, 0·54-0·78). Grade 3 or 4 haematological adverse events included decreased haemoglobin (80 [15%] of 529 assessable patients who received [177Lu]Lu-PSMA-617 plus standard of care vs 13 [6%] of 205 who received standard of care only), lymphocyte concentrations (269 [51%] vs 39 [19%]), and platelet counts (49 [9%] vs five [2%]). Treatment-related adverse events leading to death occurred in five (1%) patients who received [177Lu]Lu-PSMA-617 plus standard of care (pancytopenia [n=2], bone marrow failure [n=1], subdural haematoma [n=1], and intracranial haemorrhage [n=1]) and no patients who received standard of care only.

INTERPRETATION

[177Lu]Lu-PSMA-617 plus standard of care delayed time to worsening in HRQOL and time to skeletal events compared with standard of care alone. These findings support the use of [177Lu]Lu-PSMA-617 in patients with metastatic castration-resistant prostate cancer who received previous androgen receptor pathway inhibitor and taxane treatment.

FUNDING

Advanced Accelerator Applications (Novartis).

Randomized phase II study of zoledronate dosing every four versus eight weeks in patients with bone metastasis from lung cancer (Hanshin Cancer Group0312)

BACKGROUND

Zoledronic acid (ZA) reduces the incidence of skeletal-related events (SREs) in patients with bone metastases from solid tumors. However, the optimal dosing interval of ZA for patients with lung cancer is uncertain.

METHODS

We conducted a randomized, open-label, feasibility phase 2 trial at eight Japanese hospitals. Patients with bone metastases from lung cancer were randomly assigned to receive either 4 mg of ZA every four weeks (4wk-ZA) or every eight weeks (8wk-ZA). The primary endpoint was the time to the first SRE and the rate and types of SREs after one year. SREs were defined as pathologic bone fracture, bone radiation therapy or surgery, and spinal cord compression. Secondary endpoints were the SRE incidence at six months, pain assessment, changes in analgesic consumption, serum N-telopeptide, toxicity, and overall survival.

RESULTS

Between November 2012 and October 2018, 109 patients were randomly assigned to the 4wk-ZA group (54 patients) and the 8wk-ZA group (55 patients). The number of patients who received chemotherapy or molecular-targeted agents was 30 and 23 and 18 and 16 in the 4wk-ZA and 8wk-ZA groups, respectively. The median time to the first SRE could not be calculated because of a low SRE. The time to the first SRE of all patients did not differ between the groups (P = 0.715, HR = 1.18, 95% CI = 0.48, 2.9). The SRE rate of all patients after 12 months was 17.6% (95% CI = 8.4, 30.9%) in the 4wk-ZA and 23.3% (95% CI = 11.8, 38.6%) in the 8wk-ZA group, without significant differences between the groups. There was no difference in any secondary endpoint between groups, and these endpoints did not differ among treatment modalities.

CONCLUSIONS

An eight-week ZA interval does not increase the SRE risk for patients with bone metastasis from lung cancer and could be considered clinically.

Chronic Periodontal Infection and Not Iatrogenic Interference Is the Trigger of Medication-Related Osteonecrosis of the Jaw: Insights from a Large Animal Study (PerioBRONJ Pig Model)

Background and Objectives: Antiresorptive drugs are widely used in osteology and oncology. An important adverse effect of these drugs is medication-induced osteonecrosis of the jaw (MRONJ). There is scientific uncertainty about the underlying pathomechanism of MRONJ. A promising theory suspects infectious stimuli and local acidification with adverse effects on osteoclastic activity as crucial steps of MRONJ etiology. Clinical evidence showing a direct association between MRONJ and oral infections, such as periodontitis, without preceding surgical interventions is limited. Large animal models investigating the relationship between periodontitis and MRONJ have not been implemented. It is unclear whether the presence of infectious processes without surgical manipulation can trigger MRONJ. The following research question was formulated: is there a link between chronic oral infectious processes (periodontitis) and the occurrence of MRONJ in the absence of oral surgical procedures? Materials and Methods: A minipig large animal model for bisphosphonate-related ONJ (BRONJ) using 16 Göttingen minipigs divided into 2 groups (intervention/control) was designed and implemented. The intervention group included animals receiving i.v. bisphosphonates (zoledronate, n = 8, 0.05 mg/kg/week: ZOL group). The control group received no antiresorptive drug (n = 8: NON-ZOL group). Periodontitis lesions were induced by established procedures after 3 months of pretreatment (for the maxilla: the creation of an artificial gingival crevice and placement of a periodontal silk suture; for the mandible: the placement of a periodontal silk suture only). The outcomes were evaluated clinically and radiologically for 3 months postoperatively. After euthanasia a detailed histological evaluation was performed. Results: Periodontitis lesions could be induced successfully in all animals (both ZOL and NON-ZOL animals). MRONJ lesions of various stages developed around all periodontitis induction sites in the ZOL animals. The presence of MRONJ and periodontitis was proven clinically, radiologically and histologically. Conclusions: The results of this study provide further evidence that the infectious processes without prior dentoalveolar surgical interventions can trigger MRONJ. Therefore, iatrogenic disruption of the oral mucosa cannot be the decisive step in the pathogenesis of MRONJ.

External Validation of a Prognostic Model of Overall Survival in Men With Chemotherapy-Naïve Metastatic Castration-Resistant Prostate Cancer

PURPOSE

We have previously developed and externally validated a prognostic model of overall survival (OS) in men with metastatic, castration-resistant prostate cancer (mCRPC) treated with docetaxel. We sought to externally validate this model in a broader group of men with docetaxel-naïve mCRPC and in specific subgroups (White, Black, Asian patients, different age groups, and specific treatments) and to classify patients into validated two and three prognostic risk groupings on the basis of the model.

METHODS

Data from 8,083 docetaxel-naïve mCRPC men randomly assigned on seven phase III trials were used to validate the prognostic model of OS. We assessed the predictive performance of the model by computing the time-dependent area under the receiver operating characteristic curve (tAUC) and validated the two-risk (low and high) and three-risk prognostic groups (low, intermediate, and high).

RESULTS

The tAUC was 0.74 (95% CI, 0.73 to 0.75), and when adjusting for the first-line androgen receptor (AR) inhibitor trial status, the tAUC was 0.75 (95% CI, 0.74 to 0.76). Similar results were observed by the different racial, age, and treatment subgroups. In patients enrolled on first-line AR inhibitor trials, the median OS (months) in the low-, intermediate-, and high-prognostic risk groups were 43.3 (95% CI, 40.7 to 45.8), 27.7 (95% CI, 25.8 to 31.3), and 15.4 (95% CI, 14.0 to 17.9), respectively. Compared with the low-risk prognostic group, the hazard ratios for the high- and intermediate-risk groups were 4.3 (95% CI, 3.6 to 5.1; P < .0001) and 1.9 (95% CI, 1.7 to 2.1; P < .0001).

CONCLUSION

This prognostic model for OS in docetaxel-naïve men with mCRPC has been validated using data from seven trials and yields similar results overall and across race, age, and different treatment classes. The prognostic risk groups are robust and can be used to identify groups of patients for enrichment designs and for stratification in randomized clinical trials.

Targeting strategies for bone diseases: signaling pathways and clinical studies

Since the proposal of Paul Ehrlich's magic bullet concept over 100 years ago, tremendous advances have occurred in targeted therapy. From the initial selective antibody, antitoxin to targeted drug delivery that emerged in the past decades, more precise therapeutic efficacy is realized in specific pathological sites of clinical diseases. As a highly pyknotic mineralized tissue with lessened blood flow, bone is characterized by a complex remodeling and homeostatic regulation mechanism, which makes drug therapy for skeletal diseases more challenging than other tissues. Bone-targeted therapy has been considered a promising therapeutic approach for handling such drawbacks. With the deepening understanding of bone biology, improvements in some established bone-targeted drugs and novel therapeutic targets for drugs and deliveries have emerged on the horizon. In this review, we provide a panoramic summary of recent advances in therapeutic strategies based on bone targeting. We highlight targeting strategies based on bone structure and remodeling biology. For bone-targeted therapeutic agents, in addition to improvements of the classic denosumab, romosozumab, and PTH1R ligands, potential regulation of the remodeling process targeting other key membrane expressions, cellular crosstalk, and gene expression, of all bone cells has been exploited. For bone-targeted drug delivery, different delivery strategies targeting bone matrix, bone marrow, and specific bone cells are summarized with a comparison between different targeting ligands. Ultimately, this review will summarize recent advances in the clinical translation of bone-targeted therapies and provide a perspective on the challenges for the application of bone-targeted therapy in the clinic and future trends in this area.

Management of bone metastasis in prostate cancer

Progression of bone metastases is the primary cause of death in prostate cancer, and skeletal-related events (SREs), including pathologic fractures, spinal cord compression, radiation, or surgery to bone can impair patients' quality of life. Over the past decade, the development of cytotoxic agents, androgen-receptor-axis-targeted therapies (ARATs), and radioligand therapies has prolonged overall survival of prostate cancer patients with bone metastases and reduced the risk of SREs. The use of bone-modifying agents has also contributed to the reduced risk of SREs. Initial use of a cytotoxic agent, docetaxel, or an ARAT agent with androgen deprivation therapy (ADT) is the current approach to metastatic castration-sensitive prostate cancer. However, there is no consensus on the optimal medication for upfront use in combination with ADT, or on specific patient selection. Recently, next-generation imaging modalities, such as whole-body magnetic resonance imaging and prostate-specific membrane antigen-positron emission tomography have been utilized to detect bone metastases at an early stage. In addition, metastasis-directed therapy, such as stereotactic body radiation therapy, has been attempted. In the future, patients with bone metastatic prostate cancer will be divided into subgroups and their treatment options will be tailored to their specific characteristics.

RANKL and RANK in Cancer Therapy

Receptor activator of nuclear factor-κB (RANK) and its ligand (RANKL) are key regulators of mammalian physiology such as bone metabolism, immune tolerance and antitumor immunity, and mammary gland biology. Here, we explore the multiple functions of RANKL/RANK in physiology and pathophysiology and discuss underlying principles and strategies to modulate the RANKL/RANK pathway as a therapeutic target in immune-mediated cancer treatment.

Hormone sensitive protocol for metastatic prostate cancer, an update

To review and update last protocols in hormone sensitive metastatic prostate cancer for improving clinical management in routine. Evidence analysis available about recent updates protocols in hormone sensitive metastatic prostate cancer according to expert panel of clinicians about this field. A nominal consensus group for unify and improve the recommendations to the management of sensitive metastatic prostate cancer patients is currently needed. This document unifies and improve the management of patients with hormone sensitive metastatic prostate cancer, with a methodology that combines data quantitative and qualitative and based on the participation of a broad scientific committee appointed by the Spanish Association of Urology.

ACR Appropriateness Criteria® Management of Vertebral Compression Fractures: 2022 Update

Vertebral compression fractures (VCFs) can have a variety of etiologies, including trauma, osteoporosis, or neoplastic infiltration. Osteoporosis related fractures are the most common cause of VCFs and have a high prevalence among all postmenopausal women with increasing incidence in similarly aged men. Trauma is the most common etiology in those >50 years of age. However, many cancers, such as breast, prostate, thyroid, and lung, have a propensity to metastasize to bone, which can lead to malignant VCFs. Indeed, the spine is third most common site of metastases after lung and liver. In addition, primary tumors of bone and lymphoproliferative diseases such as lymphoma and multiple myeloma can be the cause of malignant VCFs. Although patient clinical history could help raising suspicion for a particular disorder, the characterization of VCFs is usually referred to diagnostic imaging. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances in which evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Case Report: Long-term complete response to PSMA-targeted radioligand therapy and abiraterone in a metastatic prostate cancer patient

Despite decades of research and clinical trials, metastatic castration-resistant prostate cancer (mCRPC) remains incurable and typically fatal. Current treatments may provide modest increases in progression-free survival but can come with significant adverse effects and are disaggregated from the diagnostic imaging needed to fully assess the spread of metastatic disease. A theranostic approach, using radiolabeled ligands that target the cell surface protein PSMA, simplifies the visualization and disease treatment process by enabling both to use similar agents. Here, we describe an exemplary case wherein a gentleman in his 70s with mCRPC on diagnosis was treated with 177Lu-PSMA-617 and abiraterone, and remains disease-free to date, over five years later.

MicroRNA in medication related osteonecrosis of the jaw: a review

Medication related osteonecrosis of the jaw (MRONJ) is a condition caused by inhibition of the osteoclast activity by the anti-resorptive and anti-angiogenic drugs. Clinically, there is an exposure of the necrotic bone or a fistula which fails to heal for more than 8 weeks. The adjacent soft tissue is inflamed and pus may be present as a result of the secondary infection. To date, there is no consistent biomarker that could aid in the diagnosis of the disease. The aim of this review was to explore the literature on the microRNAs (miRNAs) related to medication related osteonecrosis of the jaw, and to describe the role of each miRNA as a biomarker for diagnostic purpose and others. Its role in therapeutics was also searched. It was shown that miR-21, miR-23a, and miR-145 were significantly different in a study involving multiple myeloma patients as well as in a human-animal study while miR-23a-3p and miR-23b-3p were 12- to 14-fold upregulated compared to the control group in an animal study. The role of the microRNAs in these studies were for diagnostics, predictor of progress of MRONJ and pathogenesis. Apart from its potential diagnostics role, microRNAs have been shown to be bone resorption regulator through miR-21, miR-23a and miR-145 and this could be utilized therapeutically.

Examination of Risk Factors and Expression Patterns of Atypical Femoral Fractures Using the Japanese Adverse Drug Event Report Database: A Retrospective Pharmacovigilance Study

Atypical femoral fracture (AFF) is a rare complication related to the use of bisphosphonates (BPs). Herein, we analyzed the risk factors and onset patterns of AFF using the Japanese Adverse Drug Event Report database and reported the findings. First, the independent risk factors for AFF were gender (female), high body mass index, and medical history of osteoporosis, arthritis, and systemic lupus erythematosus (SLE). Drug-related risk factors for AFF included BPs (i.e., alendronic acid, ibandronic acid, etidronic acid, zoledronic acid, minodronic acid, risedronic acid), denosumab, prednisolone, lansoprazole, rabeprazole, exemestane, letrozole, eldecalcitol, and menatetrenone. Therefore, it appears that AFF is influenced by a combination of patient backgrounds and drugs, and that the risk of developing AFF is particularly high in patients with fragile bones (e.g., osteoporosis, arthritis, and SLE). Second, in the analysis of AFF onset patterns, the onset of AFF from BPs and denosumab took a long time (>1 year) to develop. Analysis using a Weibull distribution showed wear-out failure-type AFF onset for BPs and denosumab, and both osteoporosis and cancer patients with long-term administration of these drugs showed a tendency to have an increased risk of onset. AFF developed earlier in osteoporosis patients with long-term administration of BPs and denosumab than in cancer patients.