Skeletal complications in cancer patients with bone metastases

Mandibular metastasis of pulmonary adenocarcinoma: How unexpected could it be?

OBJECTIVE

Metastatic tumours of bone must be considered in all patients with unexplained bone pain and particularly in patients who present with a known cancer, localised pain at multiple sites, and radiographic findings suggestive of metastasis. The purpose of this report was to present a case of a pathological fracture of the mandible as a consequence of metastatic pulmonary adenocarcinoma.

MATERIALS AND METHODS

In July 2018 a 68-year-old male patient was hospitalised because of pulmonary adenocarcinoma and attended our department for an oral maxillo-facial evaluation. He complained of pain and swelling in the right temporomandibular region resulting in a reported functional limitation. An Orthopantomogram (OPG) demonstrated a right intracapsular condylar compound fracture associated with an osteolytic lesion at the condyle base with jagged margins. Subsequently, a CT scan with contrast of the maxillo-facial complex and a fine-needle aspiration of the lesion was performed.

RESULTS

CT images showed the presence of a right mandibular condyle fracture associated with a large osteolytic lesion which confirmed the pathological nature of the fracture. Fine-needle aspiration of the lesion confirmed its metastatic nature. It was not possible to proceed with a mandibular resection due to the critical clinical condition of the patient who died in September 2018.

CONCLUSION

Lung cancer frequently produces lytic-type metastasis, sometimes even in the jaw. In patients with an established diagnosis of lung cancer, any radiolucent lesion of the jaw or an unexplained painful symptomatology to the oro-maxillo facial complex should be placed in differential diagnosis with metastasis of the primary tumour.

TRPV1: Receptor structure, activation, modulation and role in neuro-immune interactions and pain

In the 1990s, the identification of a non-selective ion channel, especially responsive to capsaicin, revolutionized the studies of somatosensation and pain that were to follow. The TRPV1 channel is expressed mainly in neuronal cells, more specifically, in sensory neurons responsible for the perception of noxious stimuli. However, its presence has also been detected in other non-neuronal cells, such as immune cells, β- pancreatic cells, muscle cells and adipocytes. Activation of the channel occurs in response to a wide range of stimuli, such as noxious heat, low pH, gasses, toxins, endocannabinoids, lipid-derived endovanilloid, and chemical agents, such as capsaicin and resiniferatoxin. This activation results in an influx of cations through the channel pore, especially calcium. Intracellular calcium triggers different responses in sensory neurons. Dephosphorylation of the TRPV1 channel leads to its desensitization, which disrupts its function, while its phosphorylation increases the channel's sensitization and contributes to the channel's rehabilitation after desensitization. Kinases, phosphoinositides, and calmodulin are the main signaling pathways responsible for the channel's regulation. Thus, in this review we provide an overview of TRPV1 discovery, its tissue expression as well as on the mechanisms by which TRPV1 activation (directly or indirectly) induces pain in different disease models.

Navigating Post-Traumatic Osteoporosis: A Comprehensive Review of Epidemiology, Pathophysiology, Diagnosis, Treatment, and Future Directions

Post-traumatic osteoporosis (PTO) presents a significant challenge in clinical practice, characterized by demineralization and decreased skeletal integrity following severe traumatic injuries. This literature review manuscript addresses the knowledge gaps surrounding PTO, encompassing its epidemiology, pathophysiology, risk factors, diagnosis, treatment, prognosis, and future directions. This review emphasizes the complexity of the etiology of PTO, highlighting the dysregulation of biomineralization processes, inflammatory cytokine involvement, hormonal imbalances, glucocorticoid effects, vitamin D deficiency, and disuse osteoporosis. Moreover, it underscores the importance of multidisciplinary approaches for risk mitigation and advocates for improved diagnostic strategies to differentiate PTO from other musculoskeletal pathologies. This manuscript discusses various treatment modalities, including pharmacotherapy, dietary management, and physical rehabilitation, while also acknowledging the limited evidence on their long-term effectiveness and outcomes in PTO patients. Future directions in research are outlined, emphasizing the need for a deeper understanding of the molecular mechanisms underlying PTO and the evaluation of treatment strategies' efficacy. Overall, this review provides a comprehensive overview of PTO and highlights avenues for future investigation to enhance clinical management and patient outcomes.

Prevalence and Characteristics of Pathological Fractures in Patients Referred to Specialist Palliative Care: A Retrospective Study From India

Background: Prevalence of pathological fractures in palliative care is less studied. This study aimed to determine the annual prevalence of pathological fractures and describe the characteristics and treatments in patients with pathological fractures referred to a specialist palliative care clinic in a tertiary care cancer center in India. Methods: Data of adult cancer patients newly referred to the specialist palliative care clinic over 1 year with a clinico-radiological diagnosis of pathological fracture was included. Key outcomes of interest were annual prevalence, clinical characteristics, symptoms and treatments offered. Results: 75 out of 5800 (1.29%) patients newly referred to the clinic over 1 year had pathological fractures. Lung cancer was the most common primary diagnosis (n = 23).Dorsal spine (n = 25) was the most common site of fracture. Pain was the predominant symptom. Mean pain score was 7.04(SD = 1.75) and 42 patients (56%) required strong opioids for analgesia. Only 11 (16%) patients underwent surgical fixation. Median duration from diagnosis of cancer to occurrence of fracture was found to be 329 days. Treatment goals changed to best supportive care in 33 patients (44%) post fracture. Patients with bone and soft tissue neoplasms and those who received only chemotherapy previously had a higher risk of occurrence of fractures. Conclusion: Annual prevalence of pathological fractures in patients referred to the specialist palliative care clinic was 1.29%. It was associated with significant symptom burden and affected oncological treatments. Close monitoring of patients with bone metastases is crucial and proactive implementation of prophylactic measures to prevent such skeletal related events is warranted.

GRP78 promotes bone metastasis of prostate cancer by regulating bone microenvironment through Sonic hedgehog signaling

Bone metastasis is the leading cause of tumor-related deaths in patients with prostate cancer (PCa). The interactions between PCa and the bone microenvironment form a vicious cycle. However, the complex molecular mechanism by which PCa regulates the bone microenvironment remains unclear. To determine the role of glucose-regulated protein (GRP78) in bone metastasis and growth, we established intracardiac injection and tibial injection models, and performed their histological staining. To assess the effect of GRP78 on the differentiation of osteoblasts and osteoclasts, we performed cell co-culture, enzyme-linked immunosorbent assay, alizarin red staining, and tartrate-resistant acid phosphatase staining. We found that GRP78 is upregulated in PCa tissues and that its upregulation is associated with PCa progression in patients. Functional experiments showed that GRP78 overexpression in PCa cells considerably promotes bone metastasis and induces bone microstructure changes. Silencing GRP78 substantially inhibits the migration and invasion of PCa cells in vitro and bone metastasis and tumor growth in vivo. Mechanistically, GRP78 promotes the migration and invasion of PCa cells via the Sonic hedgehog (Shh) signaling pathway. Cell co-culture showed that GRP78 promotes the differentiation of osteoblasts and osteoclasts through Shh signaling. Our findings suggest that tumor-bone matrix interactions owing to GRP78-activated paracrine Shh signaling by PCa cells regulate the differentiation of osteoblasts and osteoclasts. This process promotes bone metastasis and the proliferation of PCa cells in the bone microenvironment. Targeting the GRP78/Shh axis can serve as a therapeutic strategy to prevent bone metastasis and improve the quality of life of patients with PCa.

Epigenetic regulation of bone remodeling and bone metastasis

Bone remodeling is a continuous and dynamic process of bone formation and resorption to maintain its integrity and homeostasis. Bone marrow is a source of various cell lineages, including osteoblasts and osteoclasts, which are involved in bone formation and resorption, respectively, to maintain bone homeostasis. Epigenetics is one of the elementary regulations governing the physiology of bone remodeling. Epigenetic modifications, mainly DNA methylation, histone modifications, and non-coding RNAs, regulate stable transcriptional programs without causing specific heritable alterations. DNA methylation in CpG-rich promoters of the gene is primarily correlated with gene silencing, and histone modifications are associated with transcriptional activation/inactivation. However, non-coding RNAs regulate the metastatic potential of cancer cells to metastasize at secondary sites. Deregulated or altered epigenetic modifications are often seen in many cancers and interwound with bone-specific tropism and cancer metastasis. Histone acetyltransferases, histone deacetylase, and DNA methyltransferases are promising targets in epigenetically altered cancer. High throughput epigenome mapping and targeting specific epigenetics modifiers will be helpful in the development of personalized epi-drugs for advanced and bone metastasis cancer patients. This review aims to discuss and gather more knowledge about different epigenetic modifications in bone remodeling and metastasis. Further, it provides new approaches for targeting epigenetic changes and therapy research.

Parathyroid hormone and trabectedin have differing effects on macrophages and stress fracture repair

Stress fractures occur as a result of repeated mechanical stress on bone and are commonly found in the load-bearing lower extremities. Macrophages are key players in the immune system and play an important role in bone remodeling and fracture healing. However, the role of macrophages in stress fractures has not been adequately addressed. We hypothesize that macrophage infiltration into a stress fracture callus site promotes bone healing. To test this, a unilateral stress fracture induction model was employed in which the murine ulna of four-month-old, C57BL/6 J male mice was repeatedly loaded with a pre-determined force until the bone was displaced a distance below the threshold for complete fracture. Mice were treated daily with parathyroid hormone (PTH, 50 μg/kg/day) starting two days before injury and continued until 24 h before euthanasia either four or six days after injury, or treated with trabectedin (0.15 mg/kg) on the day of stress fracture and euthanized three or seven days after injury. These treatments were used due to their established effects on macrophages. While macrophages have been implicated in the anabolic effects of PTH, trabectedin, an FDA approved chemotherapeutic, compromises macrophage function and reduces bone mass. At three- and four-days post injury, callus macrophage numbers were analyzed histologically. There was a significant increase in macrophages with PTH treatment compared to vehicle in the callus site. By one week of healing, treatments differentially affected the bony callus as analyzed by microcomputed tomography. PTH enhanced callus bone volume. Conversely, callus bone volume was decreased with trabectedin treatment. Interestingly, concurrent treatment with PTH and trabectedin rescued the reduction observed in the callus with trabectedin treatment alone. This study reports on the key involvement of macrophages during stress fracture healing. Given these observed outcomes on macrophage physiology and bone healing, these findings may be important for patients actively receiving either of these FDA-approved therapeutics.

Establishment of bone-targeted nano-platform and the study of its combination with 2-deoxy-d-glucose enhanced photodynamic therapy to inhibit bone metastasis

At present, simple anti-tumor drugs are ineffective at targeting bone tissue and are not purposed to treat patients with bone metastasis. In this study, zoledronic acid (ZOL) demonstrated excellent bone-targeting properties as a bone-targeting ligand. The metal-organic framework (MOF) known as ZIF-90 was modified with ZOL to construct a bone-targeting-based drug delivery system. Chlorin e6 (Ce6) was loaded in the bone-targeted drug delivery system and combined with 2-deoxy-D-glucose (2-DG), which successfully treated bone tumors when enhanced photodynamic therapy was applied. The Ce6@ZIF-PEG-ZOL (Ce6@ZPZ) nanoparticles were observed to have uniform morphology, a particle size of approximately 210 nm, and a potential of approximately -30.4 mV. The results of the bone-targeting experiments showed that Ce6@ZPZ exhibited a superior bone-targeted effect when compared to Ce6@ZIF-90-PEG. The Ce6@ZPZ solution was subjected to 660 nm irradiation and the resulting production of reactive oxygen species increased over time, which could be further increased when Ce6@ZPZ was used in combination with 2-DG. Their combination had a stronger inhibitory capacity against tumor cells than either 2-DG or Ce6@ZPZ alone, increasing the rate of tumor cell apoptosis. The apoptosis rate caused by HGC-27 was 61.56% when 2-DG was combined with Ce6@ZPZ. In vivo results also showed that Ce6@ZPZ combined with 2-DG maximally inhibited tumor growth and prolonged mice survival compared to the other experimental groups. Therefore, the combination of PDT and glycolytic inhibitors serves as a potential option for the treatment of cancer.

BeTTer Outcomes Workgroup Health Quality Initiative to optimize bone health for prostate cancer patients in the British Columbia Cancer System

INTRODUCTION

Bone-targeted therapies (BTTs) are integral to the management of bone metastases in metastatic castration-resistant prostate cancer (mCRPC). BTTs vary considerably in referral and drug access pathways and optimal BTT use requires multi-specialty consultation and supervision. Health quality improvement (HQI) has become the predominant framework to improve patient care in multidisciplinary settings.

METHODS

HQI initiatives on use of BTT in mCRPC were developed and evaluated in five centers of a provincial cancer center network using Plan-Do-Study-Act (PDSA) methodology. Multidisciplinary teams (MDTs) completed a common quality assessment form and an HQI template and then implemented an HQI initiative. Feedback and findings were shared and discussed at regional events. It was subsequently determined whether to adopt, adapt, or abandon initiatives.

RESULTS

Patterns of unmet needs varied across type of BTT. Gaps in use of radium-223 were mostly referral and education issues that could be directly addressed at the local level by participating clinician teams. Conversely, most supportive BTT gaps were related to coverage and resourcing support. HQI initiatives selected by each site consisted of implementation or expansion of local MDT meetings, referral documents, databases, and improvement charters. The main HQI initiative was completed in four sites and was adapted or adopted in three. Improvements in BTT use were observed in two of three centers with data on HQI process measures.

CONCLUSIONS

Despite the overall heterogenous structure of the groups and metrics used, this study demonstrated that the PDSA framework provides the needed structure for improvements in BTT use in mCRPC across multiple sites.

Spatially patterned 3D model mimics key features of cancer metastasis to bone

Bone is the most common target of metastasis in breast cancer and prostate cancer, leading to significant mortality due to lack of effective treatments. The discovery of novel therapies has been hampered by a lack of physiologically relevant in vitro models that can mimic key clinical features of bone metastases. To fill this critical gap, here we report spatially patterned, tissue engineered 3D models of breast cancer and prostate cancer bone metastasis which mimic bone-specific invasion, cancer aggressiveness, cancer-induced dysregulation of bone remodeling, and in vivo drug response. We demonstrate the potential of integrating such 3D models with single-cell RNA sequencing to identify key signaling drivers of cancer metastasis to bone. Together, these results validate that spatially patterned 3D bone metastasis models mimic key clinical features of bone metastasis and can serve as a novel research tool to elucidate bone metastasis biology and expedite drug discovery.

Factors Predicting the Final Diagnosis in Image-Guided Percutaneous Needle Biopsy for Suspected Spinal Tumors

In cases of suspected spinal tumors on imaging studies, a biopsy is often necessary for establishing the diagnosis. Predictive factors for tumors or malignancies may help in scheduling biopsies or avoiding unnecessary ones. However, there have been few studies on determining these factors. We aimed to determine the factors associated with the final diagnosis in cases requiring spinal biopsy. This study included 117 patients who underwent image-guided (fluoroscopy- or computed tomography [CT]-guided) needle biopsy of the spine. Data on patient demographic, pathological diagnoses, and final diagnoses were retrospectively collected from the medical records. The imaging features and location of lesions were also evaluated on CT and magnetic resonance imaging. Furthermore, factors related to tumors or malignancies were analyzed. The diagnostic accuracy of biopsy was 94.0%, and there was no difference in the diagnostic accuracy between the fluoroscopic and CT-guided biopsies. Sixty-six and fifty-six patients were diagnosed with spinal tumors and malignant tumors, respectively. Multivariate analysis revealed that a history of malignant tumors and the presence of pedicle lesions and/or extravertebral lesions were related factors for both tumors or malignancy in the final diagnosis. These findings can help determine the necessity for or timing of biopsy in patients with suspected spinal tumors.

Nanoparticle-mediated synergistic drug combination for treating bone metastasis

Bone metastasis at an advanced disease stage is common in most solid tumors and is untreatable. Overexpression of receptor activator of nuclear factor κB ligand (RANKL) in tumor-bone marrow microenvironment drives a vicious cycle of tumor progression and bone resorption. Biodegradable nanoparticles (NPs), designed to localize in the tumor tissue in bone marrow, were evaluated in a prostate cancer model of bone metastasis. The combination treatment, encapsulating docetaxel, an anticancer drug (TXT-NPs), and Denosumab, a monoclonal antibody that binds to RANKL (DNmb-NPs), administered intravenously regressed the tumor completely, preventing bone resorption, without causing any mortality. With TXT-NPs alone treatment, after an initial regression, the tumor relapsed and acquired resistance, whereas DNmb-NPs alone treatment was ineffective. Only in the combination treatment, RANKL was not detected in the tumor tibia, thus negating its role in tumor progression and bone resorption. The combination treatment was determined to be safe as the vital organ tissue showed no increase in inflammatory cytokine or the liver ALT/AST levels, and animals gained weight. Overall, dual drug treatment acted synergistically to modulate the tumor-bone microenvironment with encapsulation enhancing their therapeutic potency to achieve tumor regression.

Protein Kinase D2 and D3 Promote Prostate Cancer Cell Bone Metastasis by Positively Regulating Runx2 in a MEK/ERK1/2-Dependent Manner

Advanced-stage prostate tumors metastasize to the bone, often causing death. The protein kinase D (PKD) family has been implicated in prostate cancer development; however, its role in prostate cancer metastasis remains elusive. This study examined the contribution of PKD, particularly PKD2 and PKD3 (PKD2/3), to the metastatic potential of prostate cancer cells and the effect of PKD inhibition on prostate cancer bone metastasis in vivo. Depletion of PKD2/3 by siRNAs or inhibition by the PKD inhibitor CRT0066101 in AR-positive and AR-negative castration-resistant prostate cancer cells potently inhibited colony formation and cell migration. Depletion or inhibition of PKD2/3 significantly blocked tumor cell invasion and suppressed the expression of genes related to bone metastasis in the highly invasive PC3-ML cells. The reduced invasive activity resulting from PKD2/3 depletion was in part mediated by the transcription factor Runx2, as its silencing decreased PKD2/3-mediated metastatic gene expression through the mitogen-activated protein kinase kinase/extracellular signal-regulated kinase 1/2 signaling axis. Furthermore, inhibition of PKD by CRT0066101 potently decreased the frequency of bone micrometastases in a mouse model of bone metastasis based on intracardiac injection of PC3-ML cells. These results indicate that PKD2/3 plays an important role in the bone metastasis of prostate cancer cells, and its inhibition may be beneficial for the treatment of advanced prostate cancer.

Non-small Cell Lung Carcinoma With Metastases to Various Levels of Vertebra: A Case Report and Literature Review

The consequences of lung cancer over the past century have been quite deadly and cost millions of lives. Besides the statistics that show its brutal mortality rate, the comorbidities secondary to lung cancer have had their toll and burden on patients too. Lung cancer is broadly and histologically divided into small and non-small cell lung cancers (NSCLC), with the latter associated with a heavy smoking history. Initial presentation of NSCLC varies, and many patients present with an advanced disease that has spread to different parts of the body. Metastasis to the bone can lead to severe pain requiring extreme analgesia regimens. Here, we present a case of a 68-year-old male with advanced NSCLC who initially presented with bony pain due to metastasis.

Effect of Nano- and Microzinc Supplementation on the Mineral Composition of Bones of Rats with Induced Mammary Gland Cancer

BACKGROUND

The aim of this study was to determine changes in the mineral composition of the bones of rats with chemically induced mammary gland cancer and to attempt to establish whether a specific diet modification involving the inclusion of zinc ions in two forms-nano and micro-will affect the mineral composition of the bones.

METHODS

Female Sprague-Dawley rats were used for the research. The animals were randomly assigned to three experimental groups. All animals were fed a standard diet (Labofeed H), and selected groups additionally received zinc nanoparticles or microparticles in the amount of 4.6 mg/mL. To induce mammary cancer, the animals were given 7,12-dimethyl-1,2-benz[a]anthracene. The content of Ag, As, B, Ba, Cd, Cr, Cu, Mn, Ni, Pb, Rb, Se, Sr, Tl, U, and V was determined using ICP-MS, while that of Ca, Fe, K, Mg, Na, and Zn was determined using FAAS.

RESULTS

The use of a diet enriched with zinc nano- or microparticles significantly influenced the content of the elements tested. In the bones of rats fed a diet with zinc nanoparticles, changes were found in the content of Ca, Mg, Zn, Cd, U, V, and Tl, while in the case of the diet supplemented with zinc microparticles, there were differences in six elements-Ca, Mg, B, Cd, Ag, and Pb-compared to animals receiving an unsupplemented diet.

CONCLUSIONS

The content of elements in the bone tissue of rats in the experimental model indicates disturbances of mineral metabolism in the tissue at an early stage of mammary cancer.

Beyond Antiresorptive Activity: Risedronate-Based Coordination Complexes To Potentially Treat Osteolytic Metastases

Coordination of clinically employed bisphosphonate, risedronate (RISE), to bioactive metals, Ca²⁺, Mg²⁺, and Zn²⁺, allowed the formation of bisphosphonate-based coordination complexes (BPCCs). Three RISE-based BPCCs, RISE-Ca, RISE-Mg, and RISE-Zn, were produced, and their structures were elucidated by single crystal X-ray diffraction. Interestingly, the addition of an auxiliary ligand, etidronic acid (HEDP), resulted in the recrystallized protonated form of the ligand, H-RISE. The pH-dependent structural stability of the RISE-based BPCCs was measured by means of dissolution profiles under neutral and acidic simulated physiological conditions (PBS and FaSSGF, respectively). In comparison to RISE (Actonel), the complexes showed a lower equilibrium solubility (∼70-85% in 18-24 h) in PBS, while a higher equilibrium solubility (∼100% in 3 h) in acidic media. The results point to the capacity to release this BP in a pH-dependent manner from the RISE-based BPCCs. Subsequently, the particle size of RISE-Ca was reduced, from 300 μm to ∼350 d.nm, employing the phase inversion temperature (PIT)-nanoemulsion method, resulting in nano-Ca@RISE. Aggregation measurements of nano-Ca@RISE in 1% fetal bovine serum (FBS):H₂O was monitored after 24, 48, and 72 h to study the particle size longevity in physiological media, showing that the suspended material has the potential to maintain its particle size over time. Furthermore, binding assays were performed to determine the potential binding of nano-Ca@RISE to the bone, where results show higher binding (∼1.7×) for the material to hydroxyapatite (HA, 30%) when compared to RISE (17%) in 1 d. The cytotoxicity effects of nano-Ca@RISE were compared to those of RISE against the human breast cancer MDA-MB-231 and normal osteoblast-like hFOB 1.19 cell lines by dose-response curves and relative cell viability assays in an in vitro setting. The results demonstrate that nano-Ca@RISE significantly decreases the viability of MDA-MB-231 with high specificity, at concentrations ∼2-3× lower than the ones reported employing other third-generation BPs. This is supported by the fact that when normal osteoblast cells (hFOB 1.19), which are part of the tissue microenvironment at metastatic sites, were treated with nano-Ca@RISE no significant decrease in viability was observed. This study expands on the therapeutic potential of RISE beyond its antiresorptive activity through the design of BPCCs, specifically nano-Ca@RISE, that bind to the bone and degrade in a pH-dependent manner under acidic conditions.

Calcium phosphate bone cements as local drug delivery systems for bone cancer treatment

Bone cancer is usually a metastatic disease, affecting people of all ages. Its effective therapy requires a targeted drug administration locally at the cancer site so that the surrounding healthy organs and tissues stay unharmed. Upon a thorough literature search, a tremendous number of published articles are reporting on development of calcium phosphate cements (CPCs) for the treatment of a variety of diseases, such as osteoporosis, osteoarthritis, osteomyelitis, and other musculoskeletal disorders. However, just a limited number of research employs CPCs specifically for bone cancer treatment. In this review article, we study the factors influencing the local drug release from CPCs and particularly focus on bone cancer therapy. Finally, we locate the deficiencies in the literature regarding this specific topic and propose which other perspectives should be considered and discussed in future articles.

Does the Pathologic Fracture Predict Severe Paralysis in Patients with Metastatic Epidural Spinal Cord Compression (MESCC)?-A Retrospective, Single-Center Cohort Analysis

Currently, there is uncertainty about the predictive factors for metastatic epidural spinal cord compression (MESCC) and consecutive symptomatology in tumor patients. Prognostic algorithms for identifying patients at risk for paralysis are missing. The influence of the pathologic fracture on the patient's symptoms is widely discussed in the literature and we hypothesize that pathologic fractures contribute to spinal cord compression and are therefore predictive of severe paralysis. We tested this hypothesis in 136 patients who underwent surgery for spinal metastases. The most common primary cancers were prostate (24.3%, n = 33), breast (11.0%, n = 15), lung (10.3%, n = 14), and cancer of unknown primary (10.3%, n = 14). MESCC primarily affected the thoracic (77.2%, n = 105), followed by the lumbar (13.2%, n = 18) and cervical (9.6%, n = 13) spine. Pathologic fractures occurred in 63.2% (n = 86) of patients, mainly in osteolytic metastases. On the American spinal injury association (ASIA) impairment scale (AIS), 63.2% (n = 86) of patients exhibited AIS grade D and 36.8% (n = 50) AIS grade C-A preoperatively. The presence of a pathologic fracture alone did not predict severe paralysis (AIS C-A, p = 0.583). However, the duration of sensorimotor impairments, patient age, spinal instability neoplastic score (SINS), and the epidural spinal cord compression (ESCC) grade together predicted severe paralysis (p = 0.006) as did the ESCC grade 3 alone (p = 0.028). This is in contrast to previous studies that stated no correlation between the degree of spinal cord compression and the severity of neurologic impairments. Furthermore, the high percentage of pathologic fractures found in this study is above previously reported incidences. The risk factors identified can help to predict the development of paralysis and assist in the improvement of follow-up algorithms and the timing of therapeutic interventions.

Lung Cancer With Vertebral Metastases Presenting as Low Back Pain in the Chiropractic Office: A Case Report

Lung cancer commonly metastasizes to the skeletal system, and when affecting the spine, it may initially be mistaken for a typical musculoskeletal source of back pain. We report a previously healthy 52-year-old male non-smoker with an eight-week history of low back pain that radiated into his left thigh and recent weight loss, yet no respiratory symptoms. Initially, the patient visited his primary care physician, who suspected a musculoskeletal condition and prescribed a nonsteroidal anti-inflammatory drug and muscle relaxant, then referred the patient to the chiropractor. Based on the patient's pain pattern, limited mobility, and other features, the chiropractor suspected a lumbar disc herniation. However, the patient's condition worsened during a one-week trial of care, so the chiropractor ordered magnetic resonance imaging (MRI) and, as the findings suggested vertebral metastasis, promptly referred the patient to an oncologist, who confirmed a diagnosis of lung adenocarcinoma via positron emission tomography (PET)/computed tomography and biopsy. Chiropractors should be aware of warning signs of malignancy, such as unexplained weight loss or progressive worsening despite treatment. If providers suspect spinal metastasis, they should order advanced imaging such as an MRI and refer patients to an oncologist for timely care.

Validation of Algorithms to Identify Bone Metastases Using Administrative Claims Data in a Japanese Hospital

BACKGROUND

Validated coding algorithms are essential to generate high-quality, real-world evidence from claims data studies.

OBJECTIVE

We aimed to evaluate the validity of the algorithms to identify patients with bone metastases using claims data from a Japanese hospital.

PATIENTS AND METHODS

This study used administrative claims data and electronic medical records at Juntendo University Hospital from April 2017 to March 2019. We developed two candidate claims-based algorithms to detect bone metastases, one based on diagnosis codes alone (Algorithm 1) and the other based on the combination of diagnosis and imaging test codes (Algorithm 2). Of the patients identified by Algorithm 1, 100 patients were randomly sampled. Among these 100 patients, 88 patients met the conditions of Algorithm 2; further, 12 additional patients were randomly sampled from those identified by Algorithm 2, thus obtaining a total of 100 patients for Algorithm 2. They were evaluated for their true diagnosis using the patient chart review as the gold standard. The positive predictive value (PPV) was calculated to assess the accuracy of each algorithm.

RESULTS

For Algorithm 1, 82 patients were analyzed after excluding 18 patients without diagnostic imaging reports. Of these, 69 patients were true positive by chart review, resulting in a PPV of 84.1% (95% confidence interval (CI) 74.5-90.6). For Algorithm 2, 92 patients were analyzed after excluding eight patients whose diagnoses were not judged by chart review. Of these, 76 patients were confirmed positive by chart review, yielding a PPV of 82.6% (95% CI 73.4-89.1).

CONCLUSION

Both claims-based algorithms yielded high PPVs of approximately 85%, with no improvement in PPV by adding imaging test conditions. The diagnosis code-based algorithm is sufficient and valid for identifying bone metastases in this Japanese hospital.

[Modern aspects to the diagnosis and non-surgical treatment of low back pain]

Low back pain is one of the most common complaints in primary care. This pain is usually nonspecific and musculoskeletal. However, identification and exclusion of specific causes of pain as early as possible are important for specialists since their underestimation can sometimes lead to life-threatening consequences. The authors analyze literature data on the key facts of anamnesis («red flags»), management of patients with low back pain with emphasis on modern concepts and recommendations for diagnostics, identifying the dominant nature and cause of pain, differential diagnosis, and diagnostic significance of neuroimaging. Special attention is paid to existing options for conservative (drug and non-drug therapy) and interventional treatment methods, which have become increasingly popular in recent years.

A practical dynamic nomogram model for predicting bone metastasis in patients with thyroid cancer

PURPOSE

The aim of this study was to established a dynamic nomogram for assessing the risk of bone metastasis in patients with thyroid cancer (TC) and assist physicians to make accurate clinical decisions.

METHODS

The clinical data of patients with TC admitted to the First Affiliated hospital of Nanchang University from January 2006 to November 2016 were included in this study. Demographic and clinicopathological parameters of all patients at primary diagnosis were analyzed. Univariate and multivariate logistic regression analysis was applied to build a predictive model incorporating parameters. The discrimination, calibration, and clinical usefulness of the nomogram were evaluated using the C-index, ROC curve, calibration plot, and decision curve analysis. Internal validation was evaluated using the bootstrapping method.

RESULTS

A total of 565 patients were enrolled in this study, of whom 25 (4.21%) developed bone metastases. Based on logistic regression analysis, age (OR=1.040, P=0.019), hemoglobin (HB) (OR=0.947, P<0.001) and alkaline phosphatase (ALP) (OR=1.006, P=0.002) levels were used to construct the nomogram. The model exhibited good discrimination, with a C-index of 0.825 and good calibration. A C-index value of 0.815 was achieved on interval validation analysis. Decision curve analysis showed that the nomogram was clinically useful when intervention was decided at a bone metastases possibility threshold of 1%.

CONCLUSIONS

This dynamic nomogram, with relatively good accuracy, incorporating age, HB, and ALP, could be conveniently used to facilitate the prediction of bone metastasis risk in patients with TC.

Epigenetic (De)regulation in Prostate Cancer

Prostate cancer (PCa) is a heterogeneous disease exhibiting both genetic and epigenetic deregulations. Epigenetic alterations are defined as changes not based on DNA sequence, which include those of DNA methylation, histone modification, and chromatin remodeling. Androgen receptor (AR) is the main driver for PCa and androgen deprivation therapy (ADT) remains a backbone treatment for patients with PCa; however, ADT resistance almost inevitably occurs and advanced diseases develop termed castration-resistant PCa (CRPC), due to both genetic and epigenetic changes. Due to the reversible nature of epigenetic modifications, inhibitors targeting epigenetic factors have become promising anti-cancer agents. In this chapter, we focus on recent studies about the dysregulation of epigenetic regulators crucially involved in the initiation, development, and progression of PCa and discuss the potential use of inhibitors targeting epigenetic modifiers for treatment of advanced PCa.

Development of an evidence-based educational resource in oncology: 'Living safely with bone metastases'

Objective

To create an evidence-based patient education resource to better support cancer patients with bone metastases in carrying out safe movements during activities of daily living, to maintain their bone health and reduce the risk of fractures.

Methods

A quality improvement project was conducted in three phases: Development of the Resource, Preliminary Feedback and Revision, and French Canadian Translation.

Results

The educational resource Living Safely with Bone Metastases focuses on safe movement, activities of daily living, and exercise, organized within the sections Move with care, Stay safe in different environments and Follow an exercise program prescribed by a physiotherapist. Translation yielded a Canadian French version Vivre en toute sécurité avec des métastases osseuses.

Conclusion

Living Safely with Bone Metastases is an accessible online and paper resource for patients and healthcare professionals, in order to promote ongoing disease management of individuals with bone metastases.

Innovation

Cancer patients with bone metastases are at high risk of pathological fractures however resources on fracture prevention are lacking. Living Safely with Bone Metastases is an innovative health education resource that fills an important gap in oncology practice and has the potential to reduce the occurrence of fractures.

Prostate cancer induced bone pain: pathobiology, current treatments and pain responses from recent clinical trials

PURPOSE

Metastatic spread of prostate cancer to the skeleton may result in debilitating bone pain. In this review, we address mechanisms underpinning the pathobiology of metastatic prostate cancer induced bone pain (PCIBP) that include sensitization and sprouting of primary afferent sensory nerve fibres in bone. We also review current treatments and pain responses evoked by various treatment modalities in clinical trials in this patient population.

METHODS

We reviewed the literature using PubMed to identify research on the pathobiology of PCIBP. Additionally, we reviewed clinical trials of various treatment modalities in patients with PCIBP with pain response outcomes published in the past 7 years.

RESULTS

Recent clinical trials show that radionuclides, given either alone or in combination with chemotherapy, evoked favourable pain responses in many patients and a single fraction of local external beam radiation therapy was as effective as multiple fractions. However, treatment with chemotherapy, small molecule inhibitors and/or immunotherapy agents, produced variable pain responses but pain response was the primary endpoint in only one of these trials. Additionally, there were no published trials of potentially novel analgesic agents in patients with PCIBP.

CONCLUSION

There is a knowledge gap for clinical trials of chemotherapy, small molecule inhibitors and/or immunotherapy in patients with PCIBP where pain response is the primary endpoint. Also, there are no novel analgesic agents on the horizon for the relief of PCIBP and this is an area of large unmet medical need that warrants concerted research attention.

Role of Interleukin-1 family in bone metastasis of prostate cancer

Prostate cancer (PCa) is one of the most fatal diseases in male patients with high bone metastatic potential. Bone metastasis severely shortens overall survival and brings skeletal-related events (SREs) which reduces the life quality of patients, and this situation is currently regarded as irreversible and incurable. The progression and metastasis of PCa are found to be closely associated with inflammatory cytokines and chemokines. As pivotal members of inflammatory cytokines, Interleukin-1 (IL-1) family plays a crucial role in this process. Elevated expression of IL-1 family was detected in PCa patients with bone metastasis, and accumulating evidences proved that IL-1 family could exert vital effects on the progression and bone metastasis of many cancers, while some members have dual effects. In this review, we discuss the role of IL-1 family in the bone metastasis of PCa. Furthermore, we demonstrate that many members of IL-1 family could act as pivotal biomarkers to predict the clinical stage and prognosis of PCa patients. More importantly, we have elucidated the role of IL-1 family in the bone metastasis of PCa, which could provide potential targets for the treatment of PCa bone metastasis and probable directions for future research.

Use of paclitaxel carried in lipid core nanoparticles in patients with late-stage solid cancers with bone metastases: Lack of toxicity and therapeutic benefits

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LDE-PTX at 175 mg/m²/3wk dose was devoid of toxicity at > 3rd line treatment.

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Among 18 LDE-PTX treated patients, 9 had PFS > 6 months and 2 had PFS > 1 yr.

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LDE-PTX diminished bone pain and improved quality of life in all treated patients.

^{Patients with heavily pretreated, late-stage cancer and bone metastasis are usually poor candidates for further chemotherapy. Previously, we showed that association to lipid nanoparticles (LDE) drastically decreases the toxicity of anti-cancer drugs. Here, we tested the hypothesis that paclitaxel (PTX) carried in LDE could benefit end-of-life patients with painful bone metastases that had been previously treated with conventional PTX. Methods: Eighteen consecutive patients with late-stage cancer, 8 with breast, 5 with prostate and 5 with lung carcinoma, aged 59±9 years, were included in this study. All were receiving opioid medication. LDE-PTX was administered at 175 mg/m 2 every 3 weeks until disease progression. Clinical imaging examinations and serum biochemistry determinations were performed to monitor disease progression. Intensity of bone pain, use of opioid medications and occurrence of pathological bone fractures were also evaluated. Results: In total, 104 chemotherapy cycles were performed and none of the patients showed clinical and laboratorial toxicities or pathological bone fractures. In all patients, pain was reduced so as to allow substitution of non-opioid for opioid medication. Median progression-free survival (PFS) was four months (95% CI 2.4-5.5), but in five patients PFS was longer than 6 months. Conclusions: Absence of observable clinical and laboratorial toxicities from LDE-PTX treatment, improvement of bone pain and the possible effect on PFS in some patients, despite previous use of conventional PTX, suggest that LDEPTX merits further clinical investigation.}

Endometrial adenocarcinoma with bone metastasis: A case report

We reported a female with endometrial adenocarcinoma who was evaluated with whole‐body bone scan for new‐onset bone pains 6 months after completion of treatment.

High affinity zoledronate-based metal complex nanocrystals to potentially treat osteolytic metastases

Formation of several materials, denoted as bisphosphonate-based coordination complexes (BPCCs), resulted from the reaction between clinically employed bisphosphonate, zoledronate (ZOLE) and bioactive metals (M²⁺ = Ca²⁺, Mg²⁺ and Zn²⁺). Six ZOLE-based BPCCs were synthesized using different variables (M²⁺ : ZOLE molar ratio, temperature, pH, and anion) and their structures were elucidated by single crystal X-ray diffraction (ZOLE-Ca forms I and II, ZOLE-Mg forms I and II, and ZOLE-Zn forms I and II). The dissolution of the ZOLE-based BPCCs was compared to that of ZOLE (Reclast®). Most of the ZOLE-based BPCCs (60-85%, in 18-24 h) present a lower dissolution and equilibrium solubility than ZOLE (∼100%, 30 min) in phosphate buffered saline (PBS), while a significantly higher dissolution is observed in acidic media (88% in 1 h). This suggests the ability to release the ZOLE content in a pH-dependent manner. Moreover, a phase inversion temperature (PIT)-nano-emulsion synthesis was performed, which demonstrated the ability to significantly decrease the crystal size of ZOLE-Ca form II from a micron-range (∼200 μm) to a nano-range (∼150 d nm), resulting in nano-Ca@ZOLE. Furthermore, low aggregation of nano-Ca@ZOLE in 10% fetal bovine serum (FBS) : PBS after 0, 24 and 48 h was demonstrated. Additionally, nano-Ca@ZOLE showed an ∼2.5x more binding to hydroxyapatite (HA, 36%) than ZOLE (15%) in 1 d. The cytotoxicity of nano-Ca@ZOLE against MDA-MB-231 (cancer cell model) and hFOB 1.19 (normal osteoblast-like cell model) cell lines was investigated. The results demonstrated significant cell growth inhibition for nano-Ca@ZOLE against MDA-MB-231, specifically at a low concentration of 3.8 μM (%RCL = 55 ± 1%, 72 h). Under the same conditions, the nanocrystals did not present cytotoxicity against hFOB 1.19 (%RCL = 100 ± 2%). These results evidence that nano-ZOLE-based BPCCs possess viable properties in terms of structure, dissolution, stability, binding, and cytotoxicity, which render them suitable for osteolytic metastasis therapy.

A bone-targeting drug delivery vehicle of a metal-organic framework conjugate with zoledronate combined with photothermal therapy for tumor inhibition in cancer bone metastasis

Chemotherapy is a conventional treatment method for metastatic bone cancer, but it has limitations, such as lower drug-targeting of bone tissues and serious side effects. Bone metastasis almost always occurs in advanced cancer, and most patients in this period have strong drug resistance, which further worsens the curative effect. To address the above-mentioned difficulties, a drug delivery platform is proposed in this paper that accomplishes the bone-targeting of drugs to efficiently inhibit tumors. First, the anti-cancer drugs 5-fluorouracil (5-Fu) and indocyanine green (ICG) were loaded into a zeolitic imidazolate framework (ZIF-90) to form 5-Fu/ICG@ZIF-90. Polyethylene glycol with zoledronic acid (ZOL) was encapsulated using 5-Fu/ICG@ZIF-90 to synthesize 5-Fu/ICG@ZIF-90-PEG-ZOL nanoparticles, which showed dimensional stability, good thermal stability, and bone-targeting ability. Second, the in vitro anti-cancer activity of the designed platform was investigated using cytotoxicity, apoptosis, live-dead staining, cell cycle, and cell ultrathin section analysis. The results indicated that the nanoparticles inhibited MCF-7 cell activity when chemotherapy was combined with PTT. Finally, H&E staining and TUNEL detection were performed in mouse organs and tumors. The nanoparticles combined with photothermal therapy (PTT) and triggered by near-infrared irradiation induce apoptosis of tumor cells in vivo, displaying a better efficacy of combined chemotherapy and photothermal therapy. Experiments conducted on the 5-Fu/ICG@ZIF-90-PEG-ZOL nanoparticles demonstrated their promising performance for cancer bone metastasis inhibition.

Using scaffolds as drug delivery systems to treat bone tumor

Surgery is the principal strategy to treat osteosarcoma and other types of bone tumors, but it causes bone defects that cannot be healed spontaneously. After surgery, patients still need to receive radiotherapy and/or chemotherapy to prevent tumor recurrence and metastasis, which leads to systemic side effects. Bone scaffolds exhibit the potentials to load cargos (drugs or growth factors) and act as drug delivery systems (DDSs) in the osteosarcoma postoperative treatment. This review introduces current types of bone scaffolds and highlights representative works using scaffolds as DDSs to treat osteosarcomas. Challenges and perspectives in the scaffold-based DDSs are also discussed. This review may provide references to develop effective and safe strategies for osteosarcoma postoperative treatment.

Intraductal Carcinoma of the Prostate as a Cause of Prostate Cancer Metastasis: A Molecular Portrait

Simple Summary

Most men with prostate cancer will live as long as those who do not have prostate cancer. However, some men will die early of their disease due to a particular type of prostate cancer associated with recurrence and metastasis: intraductal carcinoma of the prostate. In this review, we discuss the associations between intraductal carcinoma of the prostate and metastasis, and the contemporary knowledge about the molecular alterations of intraductal carcinoma of the prostate.

Abstract

Intraductal carcinoma of the prostate (IDC-P) is one of the most aggressive types of prostate cancer (PCa). IDC-P is identified in approximately 20% of PCa patients and is associated with recurrence, metastasis, and PCa-specific death. The main feature of this histological variant is the colonization of benign glands by PCa cells. Although IDC-P is a well-recognized independent parameter for metastasis, mechanisms by which IDC-P cells can spread and colonize other tissues are not fully known. In this review, we discuss the molecular portraits of IDC-P determined by immunohistochemistry and genomic approaches and highlight the areas in which more research is needed.

Prophylactic Effect of Liaison Treatment on the Occurrence of Skeletal-Related Events in Patients with Metastatic Spinal Tumours: An Exploratory Interrupted Time Series Study

Introduction

There is a growing momentum for the collaboration between multiple disciplines for the prevention and treatment of skeletal-related events (SREs) in patients with metastatic spinal tumors. However, the effectiveness of multidisciplinary approaches remains unclear. Hence, we conducted an exploratory study to examine the impact of liaison treatment for metastatic spinal tumor (LMST) on the prevention of SREs among patients with a metastatic spinal tumor.

Methods

This study was an exploratory interrupted time series conducted in a single medical center. Overall, 1,043 patients with a metastatic spinal tumor diagnosed between January 2011 and December 2020 were included. The LMST was implemented in January 2014. The LMST team consisted of the orthopedic surgery, thoracic surgery, breast and thyroid surgery, clinical oncology, urology, and radiology departments. Monthly joint conferences were held for patients with spinal instability, and the incidence of SRE was measured at 6-month intervals.

Results

Throughout the study period, we identified 66 SRE incidences. After the implementation of the LMST, a level change of −5.2% (95% confidence interval [CI]: −11.7 to 1.3, p = 0.11) was observed. Subsequently, a post-implementation trend change of −0.3% (95% CI: −2.0 to 1.5, p = 0.75) beyond the baseline was noted.

Conclusions

We suggest both immediate and gradual effects of the introduction of the LMST on deterring the development of SREs. Our results support the global trend of introducing a multidisciplinary approach for the treatment of metastatic spinal tumors.

GDF15 promotes prostate cancer bone metastasis and colonization through osteoblastic CCL2 and RANKL activation

Bone metastases occur in patients with advanced-stage prostate cancer (PCa). The cell-cell interaction between PCa and the bone microenvironment forms a vicious cycle that modulates the bone microenvironment, increases bone deformities, and drives tumor growth in the bone. However, the molecular mechanisms of PCa-mediated modulation of the bone microenvironment are complex and remain poorly defined. Here, we evaluated growth differentiation factor-15 (GDF15) function using in vivo preclinical PCa-bone metastasis mouse models and an in vitro bone cell coculture system. Our results suggest that PCa-secreted GDF15 promotes bone metastases and induces bone microarchitectural alterations in a preclinical xenograft model. Mechanistic studies revealed that GDF15 increases osteoblast function and facilitates the growth of PCa in bone by activating osteoclastogenesis through osteoblastic production of CCL2 and RANKL and recruitment of osteomacs. Altogether, our findings demonstrate the critical role of GDF15 in the modulation of the bone microenvironment and subsequent development of PCa bone metastasis.

Systemic effects of abnormal bone resorption on muscle, metabolism, and cognition

Skeletal tissue is dynamic, undergoing constant remodeling to maintain musculoskeletal integrity and balance in the human body. Recent evidence shows that apart from maintaining homeostasis in the local microenvironment, the skeleton systemically affects other tissues. Several cancer-associated and noncancer-associated bone disorders can disrupt the physiological homeostasis locally in the bone microenvironment and indirectly contribute to dysregulation of systemic body function. The systemic effects of bone on the regulation of distant organ function have not been widely explored. Recent evidence suggests that bone can interact with skeletal muscle, pancreas, and brain by releasing factors from mineralized bone matrix. Currently available bone-targeting therapies such as bisphosphonates and denosumab inhibit bone resorption, decrease morbidity associated with bone destruction, and improve survival. Bisphosphonates have been a standard treatment for bone metastases, osteoporosis, and cancer treatment-induced bone diseases. The extraskeletal effects of bisphosphonates on inhibition of tumor growth are known. However, our knowledge of the effects of bisphosphonates on muscle weakness, hyperglycemia, and cognitive defects is currently evolving. To be able to identify the molecular link between bone and distant organs during abnormal bone resorption and then treat these abnormalities and prevent their systemic effects could improve survival benefits. The current review highlights the link between bone resorption and its systemic effects on muscle, pancreas, and brain.

Nonmetastatic Castration-Resistant Prostate Cancer: Current Challenges and Trends

Prostate carcinoma is a highly prevalent biologically and clinically diverse disease, generally associated with a consistent elevation of prostate-specific antigen levels. Castration-resistant prostate cancer represents a heterogeneous clinical setting that ranges from patients with an asymptomatic prostate-specific antigen elevation after hormone blockade failure and good performance status to patients with significant debilitating symptoms and rapidly progressive disease, leading to death. Nonmetastatic castration-resistant prostate cancer is a transient disease stage defined over specific criteria established within a sensitive time period. The majority of the patients with nonmetastatic castration-resistant prostate cancer will eventually develop metastatic lesions, associated with prostate cancer-specific morbidity and mortality. However, progression to metastatic disease is a heterogeneous process still not fully understood, with studies suggesting that younger age, high Gleason score (> 7), high prostate-specific antigen levels, reduced prostate-specific antigen doubling time (< 6 months), and a rapid alkaline phosphatase rise as potentially associated factors. Although the nonmetastatic castration-resistant prostate cancer treatment landscape has substantially evolved in recent years, the disease heterogeneity makes treatment decisions for this population challenging in the effort to achieve a balance between the risk of disease progression and the toxicity of new treatments in patients who often have associated comorbidities, yet are generally asymptomatic. The present article addresses the current main challenges in nonmetastatic castration-resistant prostate cancer management, including in diagnosis, owing to the development of new imaging modalities with a direct impact in disease detection, prognostic classification, as a result of the traditionally oversimplified definition of disease aggressiveness (mainly based on prostate-specific antigen doubling time), and patient selection for the most adequate treatment.

A Method of Bone-Metastatic Tumor Progression Assessment in Mice Using Longitudinal Radiography

Many types of solid tumors metastasize to the bone, where it causes significant morbidity and mortality in patients with advanced disease. Bone metastases are not only incurable but also affect bone health which impairs patients' quality of life. In order to understand the mechanisms and develop effective treatments for bone-metastatic disease, it is first necessary to develop animal models that permit the assessment of tumor growth in the bone and progressive structural changes of the bone simultaneously. Longitudinal analysis of bone tumor progression is generally performed by bioluminescent imaging; however, this method is not able to assess progressive structural changes of the bone. Here, we describe a simple method for assessment of bone lesions using a scoring system that takes into account disease burden and bone destruction using longitudinal radiographs.

Effectiveness of Rehabilitation for Cancer Patients with Bone Metastasis

Objectives:

Advances in cancer treatment have led to extended survival, and, as a result, the number of patients with bone metastases is increasing. Activities of daily living (ADL) decrease with bone metastasis and the need for rehabilitation is increasing. This study examined the effects of rehabilitation in patients with bone metastases.

Methods:

We retrospectively reviewed data of cancer patients with bone metastasis who received rehabilitation between 2016 and 2018. Efficacy of rehabilitation was evaluated in 92 patients as the change in the Functional Independence Measure (FIM) score divided by rehabilitation days (FIM change/day) and assessed by different metastatic sites.

Results:

Overall FIM scores significantly improved after rehabilitation. Moreover, FIM change/day improved in patients with pelvic metastases (n=44) more than in patients with other metastatic sites (n=48) (P=0.015). In FIM motor components, improvements in toilet, tub/shower, walk/wheelchair, and stairs were significantly greater in patients with pelvic metastasis than in those with other metastasis sites.

Conclusions:

Rehabilitation improved ADL status to a greater extent in patients with pelvic metastases than in those with other metastasis sites. Patients with pelvic metastases may fear fractures, limiting their ADL, but rehabilitation could eliminate this fear and improve FIM.

Loss of microRNA-135b Enhances Bone Metastasis in Prostate Cancer and Predicts Aggressiveness in Human Prostate Samples

About 70% of advanced-stage prostate cancer (PCa) patients will experience bone metastasis, which severely affects patients' quality of life and progresses to lethal PCa in most cases. Hence, understanding the molecular heterogeneity of PCa cell populations and the signaling pathways associated with bone tropism is crucial. For this purpose, we generated an animal model with high penetrance to metastasize to bone using an intracardiac percutaneous injection of PC3 cells to identify PCa metastasis-promoting factors. Using genomic high-throughput analysis we identified a miRNA signature involved in bone metastasis that also presents potential as a biomarker of PCa progression in human samples. In particular, the downregulation of miR-135b favored the incidence of bone metastases by significantly increasing PCa cells' migratory capacity. Moreover, the PLAG1, JAKMIP2, PDGFA, and VTI1b target genes were identified as potential mediators of miR-135b's role in the dissemination to bone. In this study, we provide a genomic signature involved in PCa bone growth, contributing to a better understanding of the mechanisms responsible for this process. In the future, our results could ultimately translate into promising new therapeutic targets for the treatment of lethal PCa.

Morbidity and mortality of surgically treated pathologic humerus fractures compared to native humerus fractures

BACKGROUND

Despite an increasing prevalence of patients sustaining pathologic fractures of neoplastic origin, few studies have investigated 30-day postoperative complication profiles after surgical treatment of pathologic humerus fractures. The purposes of this study were to use a large nationally representative database to determine short-term complication profiles after surgical treatment of pathologic humerus fractures and assess how these complications compared with more commonly studied native humerus fractures.

METHODS

Using the National Surgical Quality Improvement Program database, we identified 30,866 patients who underwent surgical treatment for either pathologic (n = 449) or native humerus fractures (n = 30,417) from 2007 to 2017. Thirty-day postoperative complication profiles were ascertained and compared between the 2 groups using χ² analyses. Three logistic regression models were then performed to determine which complications were primarily attributable to the pathologic fracture itself vs. the increased comorbidity burden faced by these patients.

RESULTS

Patients with pathologic humerus fractures experienced significantly higher rates of death (6.0% vs. 0.3%, P < .001), serious adverse events (12.2% vs. 3.7%, P < .001), minor complications (15.8% vs. 4.8%, P < .001), extended postoperative lengths of stay (42.3% vs. 21.3%, P < .001), discharge to facilities (22.3% vs. 13.5%, P < .001), and readmissions (14.8% vs. 3.4%, P < .001) compared with patients with native humerus fractures. With respect to specific complications, patients with pathologic fractures were at significantly higher risk of pulmonary complications (1.3% vs. 0.3%, P < .001), renal complications (0.7% vs. 0.2%, P = .007), thromboembolic complications (1.6% vs. 0.6%, P = .01), and transfusions (15.1% vs. 4.1%, P < .001).

CONCLUSION

After surgical treatment, patients with pathologic humerus fractures had significantly higher complication rates compared with native humerus fractures, suggesting that guidelines and treatment algorithms for native humerus fractures may not be generalizable for those of pathologic origin. These findings have significant implications for preoperative patient counseling and may be used to negotiate higher reimbursement rates for these patients given a significantly higher morbidity and mortality than was previously described in literature. Postoperatively, orthopedic surgeons should closely monitor patients with pathologic humerus fractures for deep vein thrombosis, renal complications, and pulmonary complications, use blood-sparing techniques, and employ a multidisciplinary approach to help manage and prevent a more heterogeneous profile of postsurgical complications.

Evaluation of inter- and intra-operator reliability of manual segmentation of femoral metastatic lesions

Purpose

Accurate identification of metastatic lesions is important for improvement in biomechanical models that calculate the fracture risk of metastatic bones. The aim of this study was therefore to assess the inter- and intra-operator reliability of manual segmentation of femoral metastatic lesions.

Methods

CT scans of 54 metastatic femurs (19 osteolytic, 17 osteoblastic, and 18 mixed) were segmented two times by two operators. Dice coefficients (DCs) were calculated adopting the quantification that a DC˃0.7 indicates good reliability.

Results

Generally, rather poor inter- and intra-operator reliability of lesion segmentation were found. Inter-operator DCs were 0.54 (± 0.28) and 0.50 (± 0.32) for the first and second segmentations, respectively, whereas intra-operator DCs were 0.56 (± 0.28) for operator I and 0.71 (± 0.23) for operator II. Larger lesions scored significantly higher DCs in comparison with smaller lesions. Of the femurs with larger mean segmentation volumes, 83% and 93% were segmented with good inter- and intra-operator DCs (> 0.7), respectively. There was no difference between the mean DCs of osteolytic, osteoblastic, and mixed lesions.

Conclusion

Manual segmentation of femoral bone metastases is very challenging and resulted in unsatisfactory mean reliability values. There is a need for development of a segmentation protocol to reduce the inter- and intra-operator segmentation variation as the first step and use of computer-assisted segmentation tools as a second step as this study shows that manual segmentation of femoral metastatic lesions is highly challenging.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11548-021-02450-w.

Prophylactic Percutaneous Consolidation of Large Osteolytic Tumors of the Pelvic Ring Using Fixation by Internal Cemented Screws

Purpose To evaluate the efficacy, durability, and safety of percutaneous fixation by internal cemented screw (FICS) for prophylactic consolidation of impending pathologic fractures of the pelvic ring. Materials and Methods In this single-institute retrospective study, patients with large, minimally symptomatic to asymptomatic osteolytic tumors of the pelvic ring that were treated with percutaneous cone-beam CT-guided FICS procedures were included (January 2014 to May 2019). Follow-up cross-section imaging and clinical reports were reviewed for procedural complications and assessment of the long-term consolidation efficacy on the basis of the development of pathologic fracture or need for additional surgical intervention. All continuous variables were expressed as a mean with standard deviation, and dichotomous variables were expressed as frequencies and percentages. Results Fifty consecutive patients (mean age, 60 years ± 12; 27 men) underwent prophylactic FICS for consolidation of 54 osteolytic tumors (mean size, 51 mm ± 21.5; range, 30-114 mm). Local tumor destruction was performed in association with FICS in 38 patients (76%) using percutaneous thermal and/or radiation therapy. Follow-up exceeded a year in 35 patients (70%), with mean follow-up of 22 months ± 18 (range, 1-67 months). Long-term consolidation efficacy was 98% (49 of 50), with the development of a pathologic fracture in only one patient 20 months after FICS. Procedural complications were limited to two patients with self-resolving hematoma, one patient with inflammatory sciatic pain, and one patient with focal pain at the ischial tuberosity. Conclusion Percutaneous FICS provides a safe and durable minimally invasive treatment for the prevention of pathologic fractures of the pelvic ring. Keywords: Interventional-MSK, Percutaneous, Skeletal-Axial, Metastases, Oncology Supplemental material is available for this article. © RSNA, 2020.

Cryoablation for Palliation of Painful Bone Metastases: The MOTION Multicenter Study

PURPOSE

To assess the clinical effectiveness of cryoablation for palliation of painful bone metastases.

MATERIALS AND METHODS

MOTION (Multicenter Study of Cryoablation for Palliation of Painful Bone Metastases) (ClinicalTrials.gov NCT02511678) was a multicenter, prospective, single-arm study of adults with metastatic bone disease who were not candidates for or had not benefited from standard therapy, that took place from February 2016 to March 2018. At baseline, participants rated their pain using the Brief Pain Inventory-Short Form (reference range from 0 to 10 points); those with moderate to severe pain, who had at least one metastatic candidate tumor for ablation, were included. The primary effectiveness endpoint was change in pain score from baseline to week 8. Participants were followed for 24 weeks after treatment. Statistical analyses included descriptive statistics and logistic regression to evaluate changes in pain score over the postprocedure follow-up period.

RESULTS

A total of 66 participants (mean age, 60.8 years ± 14.3 [standard deviation]; 35 [53.0%] men) were enrolled and received cryoablation; 65 completed follow-up. Mean change in pain score from baseline to week 8 was -2.61 points (95% CI: -3.45, -1.78). Mean pain scores improved by 2 points at week 1 and reached clinically meaningful levels (more than a 2-point decrease) after week 8; scores continued to improve throughout follow-up. Quality of life improved, opioid doses were stabilized, and functional status was maintained over 6 months. Serious adverse events occurred in three participants.

CONCLUSION

Cryoablation of metastatic bone tumors provided rapid and durable pain palliation, improved quality of life, and offered an alternative to opioids for pain control.Keywords: Ablation Techniques, Metastases, Pain Management, Radiation Therapy/OncologySupplemental material is available for this article.© RSNA, 2021.

Hypercalcaemia, Renal Dysfunction, Anaemia, Bone Disease (CRAB Criteria): A Case of Lymphoma

Calcium elevation, Renal dysfunction, Anaemia and Bone disease (CRAB criteria) are usually seen in multiple myeloma (MM). We report a unique case of lymphoma with all the features of CRAB criteria. We describe a 59-year-old patient who presented with confusion, severe back pain, fatigue and constipation and was found to have hypercalcaemia, kidney dysfunction, anaemia and multiple osteolytic lesions. Physical examination and imaging did not reveal any enlarged lymph nodes. Work-up for MM (serum protein electrophoresis, serum immunofixation, bone marrow biopsy) was negative. The patient was diagnosed with diffuse large B-cell lymphoma based on a pelvic mass biopsy. Hence, our case report suggests that CRAB criteria are not pathognomonic of MM and that in the appropriate clinical scenario, lymphoma is a possible diagnosis.

LEARNING POINTS

The CRAB criteria consist of end-organ damage with hypercalcaemia, renal dysfunction, anaemia and bone involvement.The CRAB criteria are not pathognomonic of multiple myeloma, and in the appropriate clinical scenario, lymphoma is a possible diagnosis.Major mechanisms by which hypercalcaemia of malignancy can occur are tumour secretion of parathyroid hormone-related protein (PTHrP), osteolytic metastases with local release of cytokines, or tumour production of 1,25-dihydroxyvitamin D (calcitriol).

New concepts in the surgical treatment of actual and impending pathological fractures in metastatic disease

INTRODUCTION

Long bone metastases are a disease of high social importance. The goals of surgical treatment are to relieve pain, maintain or restore joint function, and prevent or treat pathological fractures. "Oligometastases" is a disease with a limited number (3-5) of metastatic lesions in the same body district, where an aggressive treatment can be carried out with "curative" intent. This study aimed to evaluate patients with bone metastases surgically treated to determine how surgical treatment can influence prognosis and quality of life, comparing solitary metastasis, oligometastases, and multiple metastases.

PATIENTS AND METHODS

This is a retrospective analysis of 130 patients with long bone metastases surgically treated between October 2015 and August 2019: 40 patients had solitary metastasis; 38 had less than three metastases (oligometastases), and 52 had multiple metastases. Surgery was resection and reconstruction with a cemented prosthesis (95) or nailing (35).

RESULTS

Overall survival was significantly better in patients with solitary metastasis or oligometastases than in those with multiple metastases (p <0.0001). Patients treated with resection and prosthesis had significantly better survival than those treated with nailing (p <0.0001). Implant complications requiring surgical revision occurred in 20 patients treated with prostheses, while no complications occurred in patients treated with nailing.

DISCUSSION

Survival of cancer patients has improved in the last two decades, leading to an increase of diagnosed metastases. Patients with oligometastases have a survival similar to those with a single metastasis. Optimal implants survival curves should stay above the curves of patients survival.

CONCLUSIONS

Since there are no differences in survival, patients with oligometastases should be treated as patients with a solitary lesion, with more aggressive surgery (wide resection and reconstruction with prosthesis). Intramedullary nailing is still indicated in metaphyseal or diaphyseal metastases in patients with advanced disease or poor prognosis when the life expectancy does not overcome the expected survival of the nail, avoiding the need for further surgery.

Role of the CXCR4/ALK5/Smad3 Signaling Pathway in Cancer-Induced Bone Pain

Purpose

The chemokine receptor, CXCR4, and the transforming growth factor-beta receptor, ALK5, both contribute to various processes associated with the sensation of pain. However, the relationship between CXCR4 and ALK5 and the possible mechanisms promoted by ALK5 in the development of pain have not been evaluated.

Materials and Methods

Tumor cell implantation (TCI) technology was used to generate a model of cancer-induced bone pain (CIBP) in rats; intrathecal (i.t.) injections of small interfering (si) RNAs targeting CXCR4 and the ALK5-specific inhibitor, RepSox, were performed. Behavioral outcomes, Western blotting, and immunofluorescence techniques were used to evaluate the expression of the aforementioned specific target proteins in the CIBP model.

Results

The results revealed that i.t. administration of siRNAs targeting CXCR4 resulted in significant reductions in both mechanical and thermal hyperalgesia in rats with CIBP and likewise significantly reduced the expression of ALK5 in the spinal cord. Similarly, i.t. administration of RepSox also resulted in significant reductions in mechanical and thermal hyperalgesia in rats with CIBP together with diminished levels of spinal p-Smad3.

Conclusion

Taken together, our results suggest that CXCR4 expression in the spinal cord may be a critical mediator of CIBP via its capacity to activate ALK5 and downstream signaling pathways.

Association of Monoamine Oxidase A with Tumor Burden and Castration Resistance in Prostate Cancer

BACKGROUND

Metastatic burden and aggressive behavior determine severity stratification and guide treatment decisions in prostate cancer (PCa). Monoamine oxidase A (MAOA) may promote tumor burden and drug/castration resistance in PCa. A positive association will pave the way for MAOA inhibitors such as moclobemide for PCa therapy.

OBJECTIVE

To analyze MAOA in peripheral blood mononuclear cells qualitatively and p38, c-Jun N-terminal kinases, nuclear factor kappa B, and their phosphorylated forms, vascular endothelial growth factor (angiogenesis), transforming growth factor beta, interleukin 6, and tumor necrosis factor-α (cytokines), Bcl-2 associated X, B-cell lymphoma 2, and P53 (apoptosis), prostate-specific membrane antigen, and epithelial cell adhesion molecules (surface markers) in plasma of patients with PCa.

METHODS

This was a 1-year pilot study in which patients with PCa were recruited and stratified into 2 groups and subgroups: treatment-naive with (M1) (n = 23) or without (M0) (n = 23) bone metastasis; hormone-sensitive prostate cancer (n = 26) or hormone/castration-resistant prostate cancer (n = 26). MAOA was detected using ELISA and other proteins were detected using immunoblotting technique.

RESULTS

MAOA was detected in 8.6% of M0 compared with 30.4% of M1 patients, and in 7.7% of hormone-sensitive compared with 27% of hormone/castration resistant PCa patients, associating it with bone metastasis and castration resistance. Multivariable regression analysis showed a correlation of MAOA with serum prostate-specific antigen, a marker for progression in PCa (Pearson correlation coefficient r = 0.30; P < 0.01). In patients with positive MAOA, there was overexpression of p38, phosphorylated-p38, c-Jun N-terminal kinases, phosphorylated c-Jun N-terminal kinases, nuclear factor kappa B, phosphorylated nuclear factor kappa B, transforming growth factor beta, vascular endothelial growth factor, interleukin 6, tumor necrosis factor α, Bcl-2 associated X, B-cell lymphoma 2, prostate-specific membrane antigen, and epithelial cell adhesion molecule in M1 compared with M0 group patients, associating these proteins with tumor burden. Overexpression of Bcl-2 associated X, tumor protein 53, c-Jun N-terminal kinases, nuclear factor kappa B, transforming growth factor beta, vascular endothelial growth factor, and prostate-specific membrane antigen and underexpression of B-cell lymphoma 2 and phosphorylated nuclear factor kappa B were observed in hormone-sensitive prostate cancer compared with hormone/castration-resistant prostate cancer, associating these proteins with castration resistance.

CONCLUSIONS

Association of key molecules of oncogenesis and metastasis with MAOA suggests that MAOA inhibitors such as moclobemide might be effective in the management of PCa.