State-of-the-art imaging for diagnosis of metastatic bone disease

Image-Guided Musculoskeletal Interventional Radiology in the Personalised Management of Musculoskeletal Tumours

Musculoskeletal image-guided interventional radiology plays a key role in diagnosing and treating a range of conditions. Recent advances have yielded a wide variety of procedures that can be applied selectively and enable the personalisation of patient care. This review aims to outline the indications, applications, and techniques of subspecialist musculoskeletal oncology interventional procedures that were used at our tertiary referral centre with a focus on how these may be used to personalise patient management. The applications of a range of diagnostic and therapeutic image-guided interventional procedures including different methods of bone and soft tissue sampling, ablation, and augmentation procedures across different types of patients and pathologies are reviewed. To supplement the reviewed literature, we included our own experience and radiology images retrospectively collected from our Picture Archiving and Communication System (PACS). We demonstrate how the range of musculoskeletal image-guided interventions provide flexibility in the diagnosis and management of different tumours across different patient populations. This study provides the musculoskeletal interventional radiologist with insight into how to appropriately utlilise different techniques to optimise the diagnosis, treatment and palliation of tumours.

Incidence, epidemiology, radiology, and classification of metastatic spine tumors: WFNS Spine Committee recommendations

Spinal metastasis (SMs) are the most encountered tumors of the spine. Their occurrence is expected roughly around one to two years after primary tumor diagnosis. Since the advent of Magnetic Resonance Imaging (MRI), this technology has been considered the gold standard for SMs diagnosis and characterization due to its precise ability to comprehend the rate of soft tissue compression/invasion (dural sac/nervous tissue), which is one of the main drivers of management strategies. Computed Tomography (CT) remains unbeatable when a detailed bony anatomy and instability assessment is searched. Nuclear medicine technologies may have a role in diagnosis when standard MR or CT study findings are inconclusive or when the extent of the systemic metastatic disease is studied. The main objective of this study is to offer an update on the epidemiology and radiology of spinal metastasis (SMs), endorsed by the WFNS Spine Committee. A systematic review of the literature of the last ten years gave 1531 results with "spine/spinal metastatic tumors/metastasis AND radiology OR imaging OR classification" as search strings in all fields, of which 56 papers were fully analyzed. The results were discussed and voted on in two consensus meetings of the WFNS (World Federation of Neurosurgical Societies) Spine Committee, reaching a positive or negative consensus using the Delphi method. The committee stated nine recommendations on two main topics: (1) Incidence and epidemiology of SMs; (2) Radiology and classifications of SMs.

Bone marrow magnetic resonance imaging (MRI): morphological and functional features from reconversion to infiltration

Bone marrow is a dynamic organ with variable composition in relation to age or pathophysiological changes. Magnetic resonance imaging (MRI) is the technique of choice to assess the different components of the bone marrow based on the different information provided by the different characteristics of the MRI sequences. This article provides an overview of the MRI appearances of normal and abnormal bone marrow. We review the MRI features of normal developmental red marrow- to yellow-conversion, reconversion and physiologic conditions. We review the key imaging techniques used in assessing bone marrow pathology in MRI, including T1-weighted, T2-weighted, Dixon chemical shift imaging and diffusion-weighted imaging, as well as dynamic contrast-enhanced (DCE) MRI. It is discussed the bone marrow characteristics in the different morphological and functional MRI sequences from the normal or abnormal conditions such as; infiltration (metastases), proliferation [multiple myeloma (MM)], vascular edema/necrosis and postreatment changes. We show the different MRI features to differentiate physiological processes from pathological processes in order to provide effective diagnoses, as well as to evaluate the optimal therapeutic monitoring assessment. Insights from recent advancements in imaging technology and emerging MRI techniques are also discussed, providing a comprehensive overview of bone marrow MRI and its clinical implications. This review provides a useful tool for radiologist to decide normal or abnormal findings from the analysis of bone marrow MRI; in order to manage and take decisions that will depend on the imaging findings. The optimal analysis of bone marrow MRI requires knowledge of the physiology of the bone marrow to interpret properly the pathology and avoid diagnostic errors.

The Role of CT and MR Imaging in Stereotactic Body Radiotherapy of the Spine: From Patient Selection and Treatment Planning to Post-Treatment Monitoring

Spine metastases (SMs) are common, arising in 70% of the cases of the most prevalent malignancies in males (prostate cancer) and females (breast cancer). Stereotactic body radiotherapy, or SBRT, has been incorporated into clinical treatment algorithms over the past decade. SBRT has shown promising rates of local control for oligometastatic spinal lesions with low radiation dose to adjacent critical tissues, particularly the spinal cord. Imaging is critically important in SBRT planning, guidance, and response monitoring. This paper reviews the roles of imaging in spine SBRT, including conventional and advanced imaging approaches for SM detection, treatment planning, and post-SBRT follow-up.

Risk factor analysis and predictive model construction for bone metastasis in newly diagnosed malignant tumor patients

OBJECTIVE

To identify risk factors for bone metastasis in patients with newly diagnosed malignant tumor and to develop a prediction model.

METHODS

Clinical data from 232 patients with newly diagnosed malignant tumors were analyzed to screen for risk factors associated with bone metastasis. A nomogram prediction model was constructed using R software. The model's performance was evaluated using Receiver Operating Characteristic (ROC) analysis, Bootstrap sampling, and Decision Curve Analysis (DCA).

RESULTS

The incidence of bone metastasis in the 232 cases with newly diagnosed malignant tumors was 21.98% (51/232). Multivariate logistic regression analysis revealed that tumor staging III-IV, lymph node metastasis, high Eastern Cancer Collaboration Group Physical Status (ECOG-PS) score, high alkaline phosphatase (ALP) expression, and high SII index were risk factors for bone metastasis at initial diagnosis (all P<0.05). The area under the curve (AUC) of the nomogram model was 0.893. Bootstrap sampling validation showed a small error of 0.017 between predicted and actual probabilities. DCA supported the utility of the model in clinical practice.

CONCLUSION

Bone metastasis in newly diagnosed malignant tumors is associated with advanced tumor staging, lymph node metastasis, high ECOG-PS score, elevated ALP expression, and a high SII index. A nomogram model based on these factors can effectively predict the risk of bone metastasis in these patients.

Artificial Intelligence in Detection, Management, and Prognosis of Bone Metastasis: A Systematic Review

BACKGROUND

Metastasis commonly occur in the bone tissue. Artificial intelligence (AI) has become increasingly prevalent in the medical sector as support in decision-making, diagnosis, and treatment processes. The objective of this systematic review was to assess the reliability of AI systems in clinical, radiological, and pathological aspects of bone metastases.

METHODS

We included studies that evaluated the use of AI applications in patients affected by bone metastases. Two reviewers performed a digital search on 31 December 2023 on PubMed, Scopus, and Cochrane library and extracted authors, AI method, interest area, main modalities used, and main objectives from the included studies.

RESULTS

We included 59 studies that analyzed the contribution of computational intelligence in diagnosing or forecasting outcomes in patients with bone metastasis. Six studies were specific for spine metastasis. The study involved nuclear medicine (44.1%), clinical research (28.8%), radiology (20.4%), or molecular biology (6.8%). When a primary tumor was reported, prostate cancer was the most common, followed by lung, breast, and kidney.

CONCLUSIONS

Appropriately trained AI models may be very useful in merging information to achieve an overall improved diagnostic accuracy and treatment for metastasis in the bone. Nevertheless, there are still concerns with the use of AI systems in medical settings. Ethical considerations and legal issues must be addressed to facilitate the safe and regulated adoption of AI technologies. The limitations of the study comprise a stronger emphasis on early detection rather than tumor management and prognosis as well as a high heterogeneity for type of tumor, AI technology and radiological techniques, pathology, or laboratory samples involved.

Management of Metastatic Spinal Disease - A Practical Approach

STUDY DESIGN

Narrative review.

OBJECTIVE

This review presents a comprehensive approach to the management of spinal metastases.

METHODS

N/A.

RESULTS

The wide spectrum of clinical presentation in spinal metastases necessitates a personalized approach to treatment planning. This includes a comprehensive diagnostic workup, oncological management, palliation of symptoms, and surgical intervention if appropriate. A systematic and multidisciplinary approach allows optimal shared decision making to reach an evidence-informed and value-congruent treatment plan for the patient. We highlight how advances in stereotactic body radiotherapy (SBRT) and separation surgery may be incorporated into clinical management from a spine surgeon's perspective.

CONCLUSION

This review summarizes the approach and management of spinal metastases, its outcomes and complications.

An objective measure of response on whole-body MRI in metastatic hormone sensitive prostate cancer treated with androgen deprivation therapy, external beam radiotherapy, and radium-223

OBJECTIVES

The aim of this study was to generate an objective method to describe MRI data to assess response in the vertebrae of patients with metastatic hormone sensitive prostate cancer (mHSPC), treated with external beam radiation therapy and systemic therapy with Radium-223 and to correlate changes with clinical outcomes.

METHODS

Three sets of whole-body MRI (WBMRI) images were utilized from 25 patients from the neo-adjuvant Androgen Deprivation Therapy pelvic Radiotherapy and RADium-223 (ADRRAD) clinical trial: MRI1 (up to 28 days before Radium-223), MRI2, and MRI3 (2 and 6 months post completion of Radium-223). Radiological response was assessed based on post baseline MRI images. Vertebrae were semi-automatically contoured in the sagittal T1-weighted (T1w) acquisitions, MRI intensity was measured, and spinal cord was used to normalize the measurements. The relationship between MRI intensity vs time to biochemical progression and radiology response was investigated. Survival curves were generated and splitting measures for survival and biochemical progression investigated.

RESULTS

Using a splitting measure of 1.8, MRI1 was found to be a reliable quantitative indicator correlating with overall survival (P = 0.023) and biochemical progression (P = 0.014). MRI (3-1) and MRI (3-2) were found to be significant indicators for patients characterized by progressive/non-progressive disease (P = 0.021, P = 0.004) and biochemical progression within/after 12 months (P = 0.007, P = 0.001).

CONCLUSIONS

We have identified a potentially useful objective measure of response on WBMRI of vertebrae containing bone metastases in mHSPC which correlates with survival/progression (prognostic) and radiology response (predictive).

ADVANCES IN KNOWLEDGE

Measurements of T1w WBMRI normalized intensity may allow identifying potentially useful response biomarkers correlating with survival, radiological response and biochemical progression.

Innovations in imaging modalities: a comparative review of MRI, long-axial field-of-view PET, and full-ring CZT-SPECT in detecting bone metastases

The accurate diagnosis of bone metastasis, a condition in which cancer cells have spread to the bone, is essential for optimal patient care and outcome. This review provides a detailed overview of the current medical imaging techniques used to detect and diagnose this critical condition focusing on three cardinal imaging modalities: positron emission tomography (PET), single photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI). Each of these techniques has unique advantages: PET/CT combines functional imaging with anatomical imaging, allowing precise localization of metabolic abnormalities; the SPECT/CT offers a wider range of radiopharmaceuticals for visualizing specific receptors and metabolic pathways; MRI stands out for its unparalleled ability to produce high-resolution images of bone marrow structures. However, as this paper shows, each modality has its own limitations. The comprehensive analysis does not stop at the technical aspects, but ventures into the wider implications of these techniques in a clinical setting. By understanding the synergies and shortcomings of these modalities, healthcare professionals can make diagnostic and therapeutic decisions. Furthermore, at a time when medical technology is evolving at a breakneck pace, this review casts a speculative eye towards future advances in the field of bone metastasis imaging, bridging the current state with future possibilities. Such insights are essential for both clinicians and researchers navigating the complex landscape of bone metastasis diagnosis.

Molecular imaging of bone metastasis

Recent advances in molecularly targeted modular designs for in vivo imaging applications has thrusted open possibilities of investigating deep molecular interactions non-invasively and dynamically. The shifting landscape of biomarker concentration and cellular interactions throughout pathological progression requires quick adaptation of imaging agents and detection modalities for accurate readouts. The synergy of state of art instrumentation with molecularly targeted molecules is resulting in more precise, accurate and reproducible data sets, which is facilitating investigation of several novel questions. Small molecules, peptides, antibodies and nanoparticles are some of the commonly used molecular targeting vectors that can be applied for imaging as well as therapy. The field of theranostics, which encompasses joint application of therapy and imaging, is successfully leveraging the multifunctional use of these biomolecules [[1], [2]]. Sensitive detection of cancerous lesions and accurate assessment of treatment response has been transformative for patient management. Particularly, since bone metastasis is one of the dominant causes of morbidity and mortality in cancer patients, imaging can be hugely impactful in this patient population. The intent of this review is to highlight the utility of molecular positron emission tomography (PET) imaging in the context of prostate and breast bone metastatic cancer, and multiple myeloma. Furthermore, comparisons are drawn with traditionally utilized bone scans (skeletal scintigraphy). Both these modalities can be synergistic or complementary for assessing lytic- and blastic- bone lesions.

Hybrid Ga-68 prostate-specific membrane antigen PET/MRI in the detection of skeletal metastasis in patients with newly diagnosed prostate cancer: Contribution of each part to the diagnostic performance

PURPOSE

Bone metastasis is essential in patients with prostate cancer (PCa) as it determines prognosis and survival. Hybrid PET/MRI allows simultaneous acquisition of PET and MRI data, thus combining the strength of both technologies allows the detection of bone marrow metastases that are missed by PET/CT. In this retrospective study, we aimed to evaluate the diagnostic efficiency of hybrid PET/MRI with Ga-68 prostate-specific membrane antigen (PSMA) in detecting skeletal metastases in newly diagnosed PCa patients and compared the effectiveness of stand-alone PSMA PET reviewing versus stand-alone whole-body (WB) MRI evaluation. We also investigated the effect of the interpretation of all PET/MR data together on clinical management.

METHODS

We studied 74 newly diagnosed PCa patients who underwent PSMA PET/MRI for staging purposes. At first, PET and MRI were evaluated separately for bone lesions on a patient-and-lesion basis and then a further joint PSMA PET/MRI interpretation was made.

RESULTS

Patient-based sensitivity, specificity, positive predictive value, negative predictive value and accuracy analysis for bone metastasis was, respectively, 1.0, 0.83, 0.54, 1.0, 0.86 for PET; 0.75, 0.96, 0.81, 0.95, 0.93 for WB MRI and 0.91, 0.95, 0.78, 0,98, 0.94 for PET/MRI. The combined PET/MRI evaluation changed the clinical impact in 13.5% of patients (eight correct and two wrong decisions) compared to PET stand-alone interpretation.

CONCLUSION

PSMA PET imaging showed superior sensitivity to WB MRI in detecting bone metastases in newly diagnosed PCa patients, whereas WB MRI has superior specificity and PPV. Furthermore, the specificity and PPV of joint PET/MRI evaluation are better than PSMA PET alone. Despite the longer acquisition period, adding WB MRI sequences to PSMA PET imaging appears beneficial for PCa patient management.

USE OF THE uCentrum SYSTEM IN THE SURGICAL TREATMENT OF DISEASES OF THE VERTEBRAL SPINE

ABSTRACT Objectives: Evaluate the treatment outcome and the performance of the uCentum spinal fixation system in treating traumatic, degenerative, and tumoral diseases of the spine. Methods: This is a therapeutic study to investigate treatment outcomes and level of evidence III, including twenty-three adult patients of both sexes undergoing surgical treatment of degenerative (13 patients), traumatic (04 patients), or tumor diseases (06 patients). Patients were prospectively evaluated using clinical parameters: pain (visual analog scale), clinical and functional assessment questionnaires (SF-36, Oswestry and Roland-Morris), and radiological criteria (arthrodesis consolidation, loosening, breakage or deformation of the implants). Results: Twenty patients were followed for a period of 01 month to 12 month (mean 6,5±7,77). Three patients died due to complications unrelated to the primary disease (traumatic brain injury, septicemia, and lung tumor). Improvements were observed in clinical parameters and scores of the evaluation questionnaires used. No implant-related complications (breakage, loosening, deformation) were observed. Conclusion: the uCentum fixation system showed great versatility for performing the surgical treatment, allowing the performance of open, percutaneous procedures, the introduction of acrylic cement inside the implants, and conversion of polyaxial screws into monoaxial screws intraoperatively. Level of Evidence III; Therapeutic Studies - Investigating the Results of Treatment.

Risk Factors, Patterns, and Distribution of Bone Metastases and Skeletal-Related Events in High-Risk Breast Cancer Patients

BACKGROUND

More than a quarter of breast cancer patients are at risk to develop recurrent metastases to the bone.

OBJECTIVE

This study was designed to identify risk factors and predilections of bone metastasis and skeletal-related events (SRE) in a population of breast cancer survivors initially diagnosed in advanced stages and with high-risks of relapse.

METHODS

Associated risk factors, distribution, and attainable treatment of bone metastasis and SRE were analyzed in a cohort of 1,329 breast cancer patients. The association with dependent variables was subsequently analyzed using multivariable logistic regression. Sociodemographic and adverse clinical characteristics were included as covariates of progression into bone metastasis and SREs.

RESULTS

Of 1329 breast cancer patients, 246 patients (18.5%) were diagnosed as metastatic breast cancer in which 232 of them (94.3%) had bone metastases. Spines were the most common sites of bone metastases (25.6%). In multivariable analysis, advanced stage at diagnosis (OR=1.840, 95%CI:1.198-2.826, P=0.005), luminal subtype (OR=1.788, 95%CI:1.206-2.652, P=0.045), lobular histology (OR=1.795, 95%CI:1.012-3/184, P=0.046), positive axillary lymph node (OR=1.771, 95%CI:1.087-2.886, P=0.022), multiple metabolic comorbidities (OR=2.193, 95%CI:1.371-3.508, P=0.001), early menopause (OR=2.136, 95%CI:1.116-4.464, P=0.046) were significantly associated with risk of recurrent bone metastases. SREs occurred in 89 (68.5%) patients. Several risk factors for SREs were early menopausal age (OR=2.342, P=0.024), advanced stages (OR=1.404, P=0.039), lobular histology (OR=2.279, P=0.007), and having multiple metabolic comorbidities (OR=1.728, P=0.039).

CONCLUSION

Bone metastases and SREs are relatively high in breast cancer patients diagnosed in advanced stages. Luminal subtypes, having multiple metabolic comorbidities, and lobular histology are associated with higher risks of recurrent bone metastases. Living in rural areas and advanced stage at diagnosis as a risk factors for bone metastases might represent a social gradient of care delivery.

Tumors of the Spine: When Can Biopsy Be Avoided?

Regarding osseous tumors of the spine, characteristic morphology is encountered in hemangioma of the vertebral body, osteoid osteoma (OO), osteochondroma, Paget's disease, and bone islands. In these cases, radiologic imaging can make a specific diagnosis and thereby avoid biopsy, especially when the radiologist has chosen the correct imaging modality to establish the diagnosis, such as thin-slice computed tomography in suspected OO. A benign lesion is suggested by a high amount of fat within the lesion, the lack of uptake of the contrast agent, and a homogeneous aspect without solid parts in a cystic tumor. Suspicion of malignancy should be raised in spinal lesions with a heterogeneous disordered matrix, distinct signal decrease in T1-weighted magnetic resonance imaging, blurred border, perilesional edema, cortex erosion, and a large soft tissue component. Biopsy is mandatory in presumed malignancy, such as any Lodwick grade II or III osteolytic lesion in the vertebral column. The radiologist plays a crucial role in determining the clinical pathway by choosing the imaging approach wisely, by narrowing the differential diagnosis list, and, when characteristic morphology is encountered, by avoiding unnecessary biopsies.

State-of-the-Art Imaging Techniques in Metastatic Spinal Cord Compression

Metastatic Spinal Cord Compression (MSCC) is a debilitating complication in oncology patients. This narrative review discusses the strengths and limitations of various imaging modalities in diagnosing MSCC, the role of imaging in stereotactic body radiotherapy (SBRT) for MSCC treatment, and recent advances in deep learning (DL) tools for MSCC diagnosis. PubMed and Google Scholar databases were searched using targeted keywords. Studies were reviewed in consensus among the co-authors for their suitability before inclusion. MRI is the gold standard of imaging to diagnose MSCC with reported sensitivity and specificity of 93% and 97% respectively. CT Myelogram appears to have comparable sensitivity and specificity to contrast-enhanced MRI. Conventional CT has a lower diagnostic accuracy than MRI in MSCC diagnosis, but is helpful in emergent situations with limited access to MRI. Metal artifact reduction techniques for MRI and CT are continually being researched for patients with spinal implants. Imaging is crucial for SBRT treatment planning and three-dimensional positional verification of the treatment isocentre prior to SBRT delivery. Structural and functional MRI may be helpful in post-treatment surveillance. DL tools may improve detection of vertebral metastasis and reduce time to MSCC diagnosis. This enables earlier institution of definitive therapy for better outcomes.

Synthesis and biological impacts of pollen shells/Fe3O4 nanoparticles composites on human MG-63 osteosarcoma cells

INTRODUCTION

Cell-adhesive surfaces play a pivotal role in biomedical engineering, as most biological reactions take place on surfaces. Pollen shell (PSh) ofPistacia vera L., as a new medical device, has previously been reported to cause cytotoxicity and apoptosis in MG-63 bone cancer cells.

METHODS

Iron oxide nanoparticles (Fe3O4NPs) were synthesized and their reaction to PShs was gauged at different concentrations, and then characterized using field emission scanning electron microscopy (FESEM), Fourier-transform infrared spectroscopy, energy dispersion X-ray spectrometer, X-ray diffraction spectra, dynamic light scattering, and vibrating sample magnetometer. Then, the biological impacts of PShs/Fe3O4NPs composites on MG-63 cells were investigated in-vitro using MTT assay, quantitative polymerase chain reaction (qPCR), Annexin V/propidium iodide, FESEM, and DAPI staining.

RESULTS

Fe3O4NPs with a size range of 24-40 nm and a zeta potential value of -37.4 mV were successfully assembled on the PShs. The viability of MG-63 cells was significantly decreased when cultured on the magnetic PShs as compared to non-magnetic PShs, in Fe3O4 concentration and time-dependent manner. In contrast, magnetic PShs had a positive effect on the viability of normal human bone marrow-derived mesenchymal stem cells (hBM-MSCs). The analysis of apoptosis-related genes in cancer cells revealed that loading Fe3O4NPs on PShs increased expression of BAX/BCL2 and caspase-3 genes. The increased apoptotic activity of combined PShs/Fe3O4NPs was further confirmed by flow cytometric measurement, morphological analysis, and DAPI staining.

CONCLUSION

The incorporation of Fe3O4NPs into PShs could effectively increase anticancer effects on MG-63 cells via the mitochondria-mediated apoptosis pathway, evident by upregulation of BAX/BCL2 ratio and caspase-3.

Mortality factors in recurrent parathyroid cancer: a pooled analysis

INTRODUCTION

Parathyroid cancer is a rare disease with high recurrence rate. The prognostic factors for recurrent parathyroid cancer are yet to be ascertained. We aimed to establish the association between recurrent parathyroid cancer and previously reported prognostic factors.

MATERIALS AND METHODS

We conducted a PubMed search using the keywords 'parathyroid cancer', 'parathyroid neoplasm', and 'hypercalcemia' during 1966-2019 and included 3272 articles. We focused on 73 patients with recurrent parathyroid cancer from 55 studies. We conducted a survival analysis using the Cox proportional hazards model with 95% confidence interval.

RESULTS

For the 73 patients included in the analysis, the mean age (± standard deviation) was 44 ± 13.2 years, wherein 36 patients were women (49.3%). During the 5236 person-months at risk (mean follow-up 71.7 months, range 3-264), 38 patients died. The incidence of local recurrence, lymph-node metastasis, lung metastasis, and bone metastasis were 60.3, 12.3, 56.2, and 24.7, respectively. Bone metastasis, disease-free interval < 1 year, and total surgeries < 3 were significant prognostic factors in univariate analysis (log-rank test P = 0.0063, P = 0.0006, and P = 0.0056, respectively). In the multivariate-adjusted analysis, the mortality risk was significantly increased in patients with bone metastasis with a hazard ratio (HR) of 4.83 (95% CI 1.16-20.2; P = 0.03), disease-free interval <=1 year of 5.92 (95% CI 1.85-18.99; P = 0.003), and total surgeries <3 of 11.29 (95% CI 2.82-45.22; P = 0.001), considering these as possible predictive prognostic factors.

CONCLUSION

Bone metastasis, duration of disease-free interval, and total number of surgeries predict survival in recurrent parathyroid cancer.

Indolent enhancing spinal lesions mimicking spinal metastasis in pediatric patients with malignant primary brain tumors

Spinal metastasis from malignant primary brain tumors (MPBTs) in pediatric patients is rare and often appears as enhancing lesions on MRI. However, some indolent enhancing spinal lesions (IESLs) resulting from previous treatment mimic metastasis on MRI, leading to unnecessary investigation and treatment. In 2005-2020, we retrospectively enrolled 12 pediatric/young patients with clinical impression of spinal metastasis and pathological diagnosis of their spinal lesions. Three patients had MPBT with IESL, and 9 patients had malignant tumors with metastases. The histopathologic diagnosis of IESL was unremarkable marrow change. We evaluated their MRI, CT, and bone scan findings. The following imaging findings of IESL vs. spinal metastasis were noted: (1) IESLs appeared round/ovoid (3/3, 100%), whereas spinal metastasis appeared irregular (9/9, 100%) (P = 0.005); (2) target-shaped enhancement was noted in (3/3, 100%) vs. (0/9, 0%) of cases, respectively (P = 0.005); (3) pathologic fracture of the vertebral body was noted in (1/3, 33.3%) vs. (9/9, 100%) of cases, respectively (P = 0.045); (4) expansile vertebral shape was noted in (0/3, 0%) vs. (9/9, 100%) of cases, respectively (P = 0.005); (5) obliteration of the basivertebral vein was noted in (0/3, 0%) vs. (9/9, 100%) of cases, respectively (P = 0.005); and (6) osteoblastic change on CT was noted in (3/3, 100%) vs. (2/9, 22.2%) of cases, respectively (P = 0.034). IESL in pediatric patients with MPBT can be differentiated from metastasis based on their imaging characteristics. We suggest close follow-up rather than aggressive investigation and treatment for IESL.

Artificial intelligence applied to musculoskeletal oncology: a systematic review

Developments in artificial intelligence have the potential to improve the care of patients with musculoskeletal tumors. We performed a systematic review of the published scientific literature to identify the current state of the art of artificial intelligence applied to musculoskeletal oncology, including both primary and metastatic tumors, and across the radiology, nuclear medicine, pathology, clinical research, and molecular biology literature. Through this search, we identified 252 primary research articles, of which 58 used deep learning and 194 used other machine learning techniques. Articles involving deep learning have mostly involved bone scintigraphy, histopathology, and radiologic imaging. Articles involving other machine learning techniques have mostly involved transcriptomic analyses, radiomics, and clinical outcome prediction models using medical records. These articles predominantly present proof-of-concept work, other than the automated bone scan index for bone metastasis quantification, which has translated to clinical workflows in some regions. We systematically review and discuss this literature, highlight opportunities for multidisciplinary collaboration, and identify potentially clinically useful topics with a relative paucity of research attention. Musculoskeletal oncology is an inherently multidisciplinary field, and future research will need to integrate and synthesize noisy siloed data from across clinical, imaging, and molecular datasets. Building the data infrastructure for collaboration will help to accelerate progress towards making artificial intelligence truly useful in musculoskeletal oncology.

Surgical treatment of metastatic bone disease of the distal extremities

Metastatic bone disease of the distal extremities, also known as acrometastasis, is very rare. Thus, there is very limited information regarding the clinical manifestations and methods of surgical treatment. The current available literature shows that acrometastases are often encountered in the context of advanced disease and are thus associated with poor patient survival. As metastatic bone disease is generally uncurable, the goal of surgical treatment is to provide the patient with good function with as few complications as possible. In this article, we discuss the clinical manifestation of acrometastases, the methods of surgical intervention, and the expected clinical outcome. Non-surgically managed pathological fractures generally remain ununited; therefore, conservative treatment is reserved for patients with poor general condition or dismal prognosis. The current evidence suggests that in lesions of the lower arm and leg, osteosynthesis (plate and screw fixation or intramedullary nail) is the most common method of reconstruction, whereas local excision or amputation are more commonly used in cases of more distal lesions (such as ankle, foot and hand). Following surgery most patients receive adjuvant radiotherapy, even though its role is poorly documented. Close collaboration between orthopedic surgeons and medical oncologists is necessary to improve patient care and treatment outcome. Further studies are needed in order to provide stronger clinical evidence and improve decision-making, in an effort to optimize the patients’ quality of life and avoid the need for revision surgery.

3D MRI of the Hand and Wrist: Technical Considerations and Clinical Applications

In the last few years, major developments have been observed in the field of magnetic resonance imaging (MRI). Advances in both scanner hardware and software technologies have witnessed great leaps, enhancing the diagnostic quality and, therefore, the value of MRI. In musculoskeletal radiology, three-dimensional (3D) MRI has become an integral component of the diagnostic pathway at our institutions. This technique is particularly relevant in patients with hand and wrist symptoms, due to the intricate nature of the anatomical structures and the wide range of differential diagnoses for most presentations. We review the benefits of 3D MRI of the hand and wrist, commonly used pulse sequences, clinical applications, limitations, and future directions. We offer guidance for enhancing the image quality and tips for image interpretation of 3D MRI of the hand and wrist.

Spine MRI: A Review of Commonly Encountered Emergent Conditions

Over the last 2 decades, the proliferation of magnetic resonance imaging (MRI) availability and continuous improvements in acquisition speeds have led to significantly increased MRI utilization across the health care system, and MRI studies are increasingly ordered in the emergent setting. Depending on the clinical presentation, MRI can yield vital diagnostic information not detectable with other imaging modalities. The aim of this text is to report on the up-to-date indications for MRI of the spine in the ED, and review the various MRI appearances of commonly encountered acute spine pathology, including traumatic injuries, acute non traumatic myelopathy, infection, neoplasia, degenerative disc disease, and postoperative complications. Imaging review will focus on the aspects of the disease process that are not readily resolved with other modalities.

Diagnostic software proposal for bone scan follow-up using false color based on the gammagrams analysis from gray tone histograms

In this work we introduce a technique to speed up the interpretation of bone scans with the aim of determining the presence of absence of metastatic disease. We use gray tone histograms resembling the use of pass band filters, in order to ensure a reliable interpretation of the bone scan, providing an accurate diagnosis. We draw particular attention to three cases. The first case corresponds to shifted histograms. If the histogram is shifted toward the origin, the bone scan is free of metastasis. If it is shifted to the right and slightly broadened, indicates the presence of a bone scan anomaly different than metastasis. On the other hand, if the histogram is broadened and shifted to the left, is suggests the presence of metastatic disease. The second case corresponds to a histogram with noticeable fluctuations, indicating the presence of metastasis. Such fluctuations could become local maxima peaks indicating the advance of the metastasis. The third case, corresponds to the false color results displayed in terms of the gray tones observed in the histogram. Such false color is assigned from the construction of a 7-color palette selected in terms of the gray tones range, easing the ad hoc false color assignation for visualization purposes. The final diagnosis is carried out in terms of the color, geometry, extension and location of the region of interest in the images. Our proposed technique has the potential to be used in high-demand oncology centers due to its simplicity and diagnostic efficiency, confirmed and tested by specialists in the Centro Medico Siglo XXI (CDMX-Mexico).

A scoping review characterizing "Choosing Wisely®" recommendations for breast cancer management

PURPOSE

Choosing Wisely (CW)® was created by the American Board of Internal Medicine (ABIM) to promote patient-physician conversations about unnecessary medical interventions. Similarly, other countries created their own panels of experts called "CW® campaigns" which review recommendations submitted by that country's oncology societies. We performed a scoping review to consolidate CW® recommendations from different groups with respect to breast cancer care.

METHODS

A systematic search of Medline and Embase was designed by an information specialist for publications presenting CW® recommendations for breast cancer care practices from 2011-2020. We also reviewed the websites of all CW® campaigns and reference sections of each CW® recommendation. Two reviewers independently screened studies for inclusion and performed data extraction. Findings were summarized narratively.

RESULTS

Review of ABIM CW® recommendations showed 19 breast cancer-related recommendations pertaining to; screening (n = 4), radiological staging (n = 2), treatment (n = 10), surveillance (n = 2), and miscellaneous (genetic testing; n = 1). Of 22 countries with CW® campaigns, 10 published recommendations for breast cancer. Over half (57%) of recommendations were supported by more than one country. No recommendations were refuted between campaigns. Two campaigns developed 3 novel recommendations on new topics, including chemotherapy in ductal carcinoma in situ (Italy) and comparison of screening imaging modalities (Portugal).

CONCLUSIONS

CW® recommendations focus on reducing overutilization of investigations and treatments. There was a high rate of consensus between different CW® campaigns. As health care systems globally move attention to reduce low-value care, further studies are required to address adherence to these current recommendations and develop new recommendations.

Recent Advances in Nanomedicine for the Diagnosis and Treatment of Prostate Cancer Bone Metastasis

Patients with advanced prostate cancer can develop painful and debilitating bone metastases. Currently available interventions for prostate cancer bone metastases, including chemotherapy, bisphosphonates, and radiopharmaceuticals, are only palliative. They can relieve pain, reduce complications (e.g., bone fractures), and improve quality of life, but they do not significantly improve survival times. Therefore, additional strategies to enhance the diagnosis and treatment of prostate cancer bone metastases are needed. Nanotechnology is a versatile platform that has been used to increase the specificity and therapeutic efficacy of various treatments for prostate cancer bone metastases. In this review, we summarize preclinical research that utilizes nanotechnology to develop novel diagnostic imaging tools, translational models, and therapies to combat prostate cancer bone metastases.

[Radiologic diagnosis of pathologic fractures]

BACKGROUND

Pathologic fractures are fractures that occur without an adequate traumatic event due to focal benign or malignant skeletal lesions. The most common causes of pathologic fractures are cystic bone lesions, plasmocytoma or multiple myeloma, and the development of osseous metastases, which is increasing due to an aging general population and advances in cancer treatment. The differentiation of pathologic fractures from stress fractures, especially osteoporotic insufficiency fractures is crucial for correct treatment planning.

OBJECTIVES

This review intends to explain the imaging characteristics of pathologic fractures. Moreover, it explains the role of imaging when pathologic fractures are suspected. In addition, the Mirels' score and the SINS (Spinal Instability Neoplastic Score), which are powerful yet easy-to-use tools for the assessment of the fracture risk of benign or malignant bony lesions of the extremities and the vertebral column, shall be introduced.

MATERIALS AND METHODS

A PubMed literature search with the following terms was conducted: "pathologic fracture", "fatigue fracture", "insufficiency fracture", "treatment of pathologic fractures", "imaging of pathologic fractures", "fracture risk", "bone metastases", "MRI of pathologic fractures", "CT of pathologic fractures", "differentiation of pathologic and insufficiency fractures", "Mirels' score", "SINS" and "spinal instability neoplastic score".

RESULTS

The definitions of pathologic, fatigue, and insufficiency fractures are explained. Moreover, the role of imaging in the clinical workup of suspected pathologic fractures and the differentiation of pathologic fractures from fatigue or insufficiency fractures as well as common scoring systems to assess the fracture risk of pathologic fractures are described.

Assessment of Bone Lesions with 18F-FDG PET Compared with 99mTc Bone Scintigraphy Leads to Clinically Relevant Differences in Metastatic Breast Cancer Management

It is unknown whether assessment of potential bone lesions in metastatic breast cancer (MBC) by ¹⁸F-FDG PET instead of ^99mTc bone scintigraphy (BS) supports clinically relevant changes in MBC management. Therefore, we retrospectively compared management recommendations based on bone lesion assessment by ¹⁸F-FDG PET plus contrast-enhanced CT (ceCT) or BS plus ceCT, for patients with newly diagnosed MBC. Methods: Baseline ceCT, BS, and ¹⁸F-FDG PET for all patients included in the IMPACT-MBC study (NCT01957332) at the University Medical Center Groningen were reviewed for bone lesions. If bone lesions were found by any imaging modality, virtual MBC management recommendations were made by a multidisciplinary expert panel, based on either ¹⁸F-FDG PET plus ceCT or BS plus ceCT. The panel had access to standard clinicopathologic information and baseline imaging findings outside the skeleton. Clinically relevant management differences between the 2 recommendations were defined either as different treatment intent (curative, noncurative, or unable to determine) or as different systemic or local treatment. If no bone lesions were found by any imaging modality, the patients were included in the analyses without expert review. Results: In total, 3,473 unequivocal bone lesions were identified in 102 evaluated patients (39% by ceCT, 26% by BS, and 87% by ¹⁸F-FDG PET). Additional bone lesions on ¹⁸F-FDG PET plus ceCT compared with BS plus ceCT led to change in MBC management recommendations in 16% of patients (95% CI, 10%-24%). BS also changed management compared with ¹⁸F-FDG PET in 1 patient (1%; 95% CI, 0%-5%). In 26% (95% CI, 19%-36%) of patients, an additional ¹⁸F-FDG PET exam was requested, because BS provided insufficient information. Conclusion: In this exploratory analysis of newly diagnosed MBC patients, ¹⁸F-FDG PET versus BS to assess bone lesions resulted in clinically relevant management differences in 16% of patients. BS delivered insufficient information in over one fourth of patients, resulting in an additional request for ¹⁸F-FDG PET. On the basis of these data, ¹⁸F-FDG PET should be considered a primary imaging modality for assessment of bone lesions in newly diagnosed MBC.

Spinal metastases treated with bipolar radiofrequency ablation with increased (>70°C) target temperature: Pain management and local tumor control

PURPOSE

To investigate the safety and clinical efficacy of bipolar radiofrequency ablation (b-RFA) with increased (>70°C) target temperature for the treatment of spine metastases with the intent of achieving pain relief or local tumor control.

MATERIALS AND METHODS

Thirty-one patients with a total of 37 metastases who were treated with b-RFA with increased temperature and vertebroplasty from January 2016 to May 2019 were retrospectively included. There were 20 women and 11 men with a mean age of 62.4±10.5 (SD) years (range: 40-78years). Patients and metastases characteristics, procedure details and clinical outcomes were analyzed.

RESULTS

Metastases were predominantly located in lumbar (22/37; 59.5%) or thoracic spine (13/37; 35.1%). Mean target temperature was 88.4±3.5 (SD) °C (range: 70-90°C). Technical success was 100% (37/37 metastases). One (1/37; 2.7%) major complication unrelated to b-RFA was reported. One (1/37; 2.7%) metastasis was lost to follow-up. Favorable outcome was noted in patients receiving b-RFA for pain management (16/20 metastases; 80%; mean follow-up, 3.4±2.9 [SD] months) or with oligometastatic/oligoprogressive disease (6/6 metastases; 100%; mean follow-up, 5.0±4.6 [SD] months). In patients receiving b-RFA to prevent complications, favorable outcome was noted in 6/10 metastases (60%; mean follow-up, 3.8±4.8 [SD] months).

CONCLUSIONS

B-RFA with increased target temperature has an excellent safety profile and results in high rates of pain relief and local metastasis control in patients with oligometastatic/oligoprogressive disease. Suboptimal results are achieved in patients receiving b-RFA to prevent complications related to the growth of the index tumor.