Epidemiological Characteristics of 1196 Patients with Spinal Metastases: A Retrospective Study

Single-cell RNA sequencing comparison of the human metastatic prostate spine tumor microenvironment

Spinal column tumors can be difficult to process for single-cell omic studies, given the heterogeneity in tissue. Here, we present a protocol for operating room-to-benchtop single-cell processing of clinical specimens from a prostate cancer patient. We describe steps for sample homogenization, red blood cell lysis, cryopreservation, and single-cell sequencing analysis. This protocol can be used to identify prognostic markers and therapeutic targets for patients with osseous spine metastases and better inform eligibility for clinical trials.

Dynamic contrast-enhanced magnetic resonance imaging parameter changes as an early biomarker of tumor responses following radiation therapy in patients with spinal metastases: a systematic review

PURPOSE

This systematic review aims to assess and summarize the clinical values of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameter changes as early biomarkers of tumor responses following radiation therapy (RT) in patients with spinal metastases.

MATERIALS AND METHODS

A systematic search was conducted on five electronic databases: PubMed, Scopus, Science Direct, Cochrane, and Embase. Studies were included if they mentioned DCE-MRI parameter changes before and after RT in patients with spinal metastases with a correlation to tumor responses based on clinical and imaging criteria. The Quality Assessment of Diagnostic Accuracy Studies 2 was used to assess study quality.

RESULTS

This systematic review included seven studies involving 107 patients. All seven studies evaluated the transfer constant (Ktrans), six studies evaluated the plasma volume fraction (Vp), three studies evaluated the extravascular extracellular space volume fraction, and two studies evaluated the rate constant. There were variations in the type of primary cancer, RT techniques used, post-treatment scan time, and median follow-up time. Despite the variations, however, the collected evidence generally suggested that significant differences could be detected in DCE-MRI parameters between before and after RT, which might reflect treatment success or failures in long-term follow-up. Responders showed higher reduction and lower values of Ktrans and Vp after RT. DCE-MRI parameters showed changes and detectable recurrences significantly earlier (up to 6 months) than conventional MRI with favorable diagnostic values.

CONCLUSION

The results of this systematic review suggested that DCE-MRI parameter changes in patients with spinal metastases could be a promising tool for treatment-response assessment following RT. Lower values and higher reduction of Ktrans and Vp after treatment demonstrated good prediction of local control. Compared to conventional MRI, DCE-MRI showed more rapid changes and earlier prediction of treatment failure.

Quality of life in patients with malignant spinal cord compression: a systematic review

INTRODUCTION

Malignant spinal cord compression (MSCC) is an oncological emergency that may result in a devastating combination of malignancy and disability. Existing quality of life (QoL) questionnaires commonly used in MSCC literature (EORTC QLQ-C30, BM-22, Brief Pain Inventory, and Spine Oncology Study Group Outcomes) may not capture all the commonly reported symptoms and lack specificity to MSCC. The primary objective of this systematic review is to determine unmet patient needs and underreported QoL issues and compile a comprehensive list of QoL issues. The secondary objective of this review is to compile all existing QoL tools and questionnaires and determine whether any QoL issues are not addressed in the existing tools currently used in the literature.

METHODS

A literature search was conducted on Ovid MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases between 1946 and February 6, 2023, to compile all QoL issues and existing questionnaires used to assess QoL in patients with MSCC. All study designs were included given that they discussed QoL issues specific to patients with MSCC.

RESULTS

The results of this systematic review identified the most frequently discussed QoL issues in the literature studying MSCC. This included direct symptoms of MSCC such as back pain, paralysis, limb weakness/numbness, and urinary/bowel incontinence. Indirect symptoms coming from radiotherapy treatment such as dysphagia, painful swallowing, mouth pain, dry mouth, diarrhea, fatigue, and nausea/vomiting were also noted. Other symptoms resulting from corticosteroid treatment included difficulty sleeping, blurring of vision, weight gain, and mood disturbance. Patients also experienced psychosocial issues such as anxiety, depression, emotional distress, low self-esteem, concerns about dependence on others, concerns about getting home, and fear about their prognosis and future.

CONCLUSION

This review highlights the QoL issues specific to patients with MSCC and QoL tools capturing these issues. Relevance of QoL issues identified in this systematic review must be prospectively validated by patients and healthcare professionals with experience in treating MSCC.

Biomaterials-enhanced bioactive agents to efficiently block spinal metastases of cancers

The spine is the most common site of bone metastases, as 20%-40% of cancer patients suffer from spinal metastases. Treatments for spinal metastases are scarce and palliative, primarily aiming at relieving bone pain and preserving neurological function. The bioactive agents-mediated therapies are the most effective modalities for treating spinal metastases because they achieve systematic and specific tumor regression. However, the clinical applications of some bioactive agents are limited due to the lack of targeting capabilities, severe side effects, and vulnerability of drug resistance. Fortunately, advanced biomaterials have been developed as excipients to enhance these treatments, including chemotherapy, phototherapy, magnetic hyperthermia therapy, and combination therapy, by improving tumor targeting and enabling sustaining and stimuli-responsive release of various therapeutic agents. Herein, the review summarizes the development of biomaterials-mediated bioactive agents for enhanced treatments of spinal metastases and predicts future research trends.

Prediction of Primary Tumor Sites in Spinal Metastases Using a ResNet-50 Convolutional Neural Network Based on MRI

We aim to investigate the feasibility and evaluate the performance of a ResNet-50 convolutional neural network (CNN) based on magnetic resonance imaging (MRI) in predicting primary tumor sites in spinal metastases. Conventional sequences (T1-weighted, T2-weighted, and fat-suppressed T2-weighted sequences) MRIs of spinal metastases patients confirmed by pathology from August 2006 to August 2019 were retrospectively analyzed. Patients were partitioned into non-overlapping sets of 90% for training and 10% for testing. A deep learning model using ResNet-50 CNN was trained to classify primary tumor sites. Top-1 accuracy, precision, sensitivity, area under the curve for the receiver-operating characteristic (AUC-ROC), and F1 score were considered as the evaluation metrics. A total of 295 spinal metastases patients (mean age ± standard deviation, 59.9 years ± 10.9; 154 men) were evaluated. Included metastases originated from lung cancer (n = 142), kidney cancer (n = 50), mammary cancer (n = 41), thyroid cancer (n = 34), and prostate cancer (n = 28). For 5-class classification, AUC-ROC and top-1 accuracy were 0.77 and 52.97%, respectively. Additionally, AUC-ROC for different sequence subsets ranged between 0.70 (for T2-weighted) and 0.74 (for fat-suppressed T2-weighted). Our developed ResNet-50 CNN model for predicting primary tumor sites in spinal metastases at MRI has the potential to help prioritize the examinations and treatments in case of unknown primary for radiologists and oncologists.

Clinical Outcome and Histological Findings After Induced Leakage of PMMA Loaded With Methotrexate and Cisplatin During Vertebroplasty: Experimental Model in Pigs

STUDY DESIGN

Animal experimental model.

OBJECTIVE

To study the clinical behavior and histological changes in the spinal cord, nerve roots and perivertebral muscles of the spine after induced leakage of polymethylmethacrylate (PMMA) loaded with antiblastic drugs during vertebroplasty in an animal model of pigs.

METHODS

We performed vertebroplasty on 25 pigs. The animals were divided into 3 groups: vertebroplasty with PMMA alone (control group), vertebroplasty with PMMA loaded with methotrexate (MTX) and vertebroplasty with PMMA loaded with cisplatin (CYS). At 2 vertebral levels, epidural and prevertebral, massive cement leaks were induced. Animals were evaluated daily. Two weeks later, the pigs were sacrificed, and the tissues that came in contact with the cement were analyzed.

RESULTS

The clinical results for each of the groups were reported. The control group had no clinical alterations. In the MTX group, 2 pigs died before 1 week due to pneumonitis. In the CYS group, 4 animals had motor impairment, and 3 of the 4 had paraplegia. The histological results were as follows: the control and MTX groups showed synovial metaplasia, inflammatory reaction, crystal deposits, and giant cell reaction in the dura mater and muscle and all the animals in the CYS group had spinal cord and muscular necrosis.

CONCLUSIONS

Massive cement leak after vertebroplasty with PMMA loaded with cisplatin is extremely toxic to the spinal cord and muscles around the spine. Therefore, its use cannot be recommended for the treatment of vertebral metastases. Using PMMA loaded with methotrexate seems to be a safe procedure, but further research is needed.

Multidisciplinary Approach to Patients With Metastatic Spinal Cord Compression: A Diagnostic Therapeutic Algorithm to Improve the Neurological Outcome

Introduction

The morbidity associated with metastatic spinal disease is significant because of spinal cord and/or nerve root compression. The purpose of this paper is to define a diagnostic-therapeutic path for patients with vertebral metastases and from this path to build an algorithm to reduce the devastating consequences of spinal cord compression.

Materials and Methods

The algorithm is born from the experience of a primary care center. A spine surgeon, an emergency room (ER) physician, a neuroradiologist, a radiation oncologist, and an oncologist form the multidisciplinary team. The ER physician or the oncologist intercept the patient with symptoms and signs of a metastatic spinal cord compression. Once the suspicion is confirmed, the following steps of the flow-chart must be triggered. The spine surgeon takes charge of the patient and, on the base of the anamnestic data and neurological examination, defines the appropriate timing for magnetic resonance imaging (MRI) in collaboration with the neuroradiologist. From the MRI outcome, the spine surgeon and the radiation oncologist consult each other to define further therapeutic alternatives. If indicated, surgical treatment should precede radiation therapy. The oncologist gets involved after surgery for systemic therapy.

Results

In 2021, the Spine and Spinal Cord Surgery department evaluated 257 patients with vertebral metastasis. Fifty-three patients presented with actual or incipient spinal cord compression. Among these, 27 were admitted due to rapid progression of symptoms, neurological deficits and/or spine instability signs. The level was thoracic in 21 cases, lumbar in 4 cases, cervical in 1 case, sacral in 1 case. Fifteen were operated on, 10 of these programmed and 5 in emergency.

Discussion

Patients with a history of malignancy can present to the ER or to the oncology department with symptoms that must be correctly framed in the context of a metastatic involvement. Even when there is no previous cancer history, the patient's pain characteristics and clinical signs must be interpreted to yield the correct diagnosis of vertebral metastasis with incipient or current spinal cord compression. The awareness of the alert symptoms and the application of an integrated paradigm consent to frame the patients with spinal cord compression, obtaining the benefits of a homogeneous step-by-step diagnostic and therapeutic path. Early surgical or radiation therapy treatment gives the best hope for preventing the worsening, or even improving, the deficits.

Conclusions

Metastatic spinal cord compression can cause neurological deficits compromising quality of life. Treatment strategies should be planned comprehensively. A multidisciplinary approach and the application of the proposed algorithm is of paramount importance to optimize the outcomes of these patients.

Interventional and Non-interventional Medical Rehabilitation Approaches to Axial Spine Pain in Vertebral Metastatic Disease

As targeted therapies help patients with advanced cancer live longer, interventions for management of axial spine pain will become more common. Unfortunately, the indications for and safety of these procedures have been relatively unexplored compared with non-cancer adults. This review focuses on the following aspects of axial spine pain management in patients with vertebral metastatic disease: (1) pathophysiology and symptoms of cancer- and non-cancer-related spine pain; (2) safety and efficacy of non-interventional rehabilitation approaches to treat this pain; (3) considerations for interventional pain approaches to acute and chronic pain in patients with vertebral metastatic disease. This review also summarizes gaps in the literature and describes specific cases in which the described interventions have been applied.

Complication Avoidance in Surgical Management of Vertebral Column Tumors

The surgical management of spinal tumors has grown increasingly complex as treatment algorithms for both primary bone tumors of the spine and metastatic spinal disease have evolved in response to novel surgical techniques, rising complication rates, and additional data concerning adjunct therapies. In this review, we discuss actionable interventions for improved patient safety in the operative care for spinal tumors. Strategies for complication avoidance in the preoperative, intraoperative, and postoperative settings are discussed for approach-related morbidities, intraoperative hemorrhage, wound healing complications, cerebrospinal fluid (CSF) leak, thromboembolism, and failure of instrumentation and fusion. These strategies center on themes such as pre-operative imaging review and medical optimization, surgical dissection informed by meticulous attention to anatomic boundaries, and fastidious wound closure followed by thorough post-operative care.

[Surgical treatment of patients with chest wall metastases]

OBJECTIVE

To evaluate postoperative outcomes in patients with chest wall metastases.

MATERIAL AND METHODS

We analyzed 40 patients who underwent surgery for chest wall metastatic lesions. Fourteen (35%) patients had sternal lesion, 26 (65%) ones - rib metastases. We used implants for chest wall defect closure in 15 (37.5%) patients. Chest wall repair with autologous tissues was performed in 19 (47.5%) patients.

RESULTS

Median survival was 17 months. Most patients (n=30, 75%) showed improvement in the quality of life according to Karnofsky and EGOG scale after surgery. Continued tumor growth occurred in 4 (10%) patients within 8-16 months after surgery. There were 2 patients who suffered from tumor recurrence accompanied by other metastatic foci (progression). Complications were diagnosed in 5 (12.5%) patients. Tactical errors were identified in 4 (10%) patients and they were associated with progression of cancer in the form of new metastatic foci within 6 months after surgery.

CONCLUSION

Active surgical approach for bone metastases in patients with favorable cancer-related prognosis can improve quality of life and survival at least in case of solitary lesions. New program for treatment strategy selection based on prognosis of life expectancy and algorithms of surgical treatment will reduce the risk of erroneous management and increase its effectiveness.

An Overview of Decision Making in the Management of Metastatic Spinal Tumors

INTRODUCTION

Spinal metastases are the most commonly encountered spinal tumors. With increasing life expectancy and better systemic treatment options, the incidence of patients seeking treatment for spinal metastasis is rising. Radical resections and conventional low-dose radiotherapy have given way to modern 'separation' surgeries and stereotactic body radiotherapy which entails lesser morbidity and improved local control. This article provides an overview of the decision making and currently available treatment options for metastatic spinal tumors.

METHODS

A MEDLINE literature search was made for studies in English language reporting on human subjects, describing results of various treatment options that are a part of multidisciplinary management of metastatic spinal tumors. The highest-quality evidence available in the literature was reviewed.

DISCUSSION

Treatment of patients with metastatic spinal tumors is largely palliative, with radiotherapy and selective surgery being the mainstays of management. Multidisciplinary management that incorporates factors like patient performance status, expected survival and systemic burden of disease and employs well-validated decision-making frameworks for guiding treatment holds the key to an effective palliative treatment strategy. Effective pain management, achieving local control, adequate neurological decompression in the setting of epidural cord compression and surgical stabilization for mechanical stabilization are the main goals of treatment.

CONCLUSION

The management of metastatic spinal tumors has been rapidly evolving; currently, limited decompression and stabilization followed by postoperative SBRT for local tumor control are associated with less morbidity and may be referred to as the current standard of care in these patients.

Microwave Ablation as a Treatment for Spinal Metastatic Tumors: A Systematic Review

BACKGROUND

Microwave ablation (MWA) is a novel technique that offers several potential advantages over existing ablation systems, which include production of larger ablation zones, shorter procedural times, and more effective heating through high impedance tissues such as bone.

METHODS

A systematic review was performed using inclusion criteria defined as follows: 1) metastatic spinal tumors treated with open or percutaneous MWA alone or in combination with other treatments, 2) available data on pain palliation and/or local tumor control, and 3) retrospective or prospective studies with at least 1 patient.

RESULTS

A total of 156 patients harboring 196 spinal lesions underwent MWA in the 8 included studies. Most studies employed the use of additional interventions, which included minimally invasive open surgery with pedicle screw fixation, traditional open surgical intervention, and cement augmentation. Despite the variability in time intervals for pain assessment, postoperative pain scores decreased considerably in both percutaneous and open MWA studies. No evidence of tumor progression was additionally seen in >80% of patients at the last follow-up across 5 studies. Complications were reported in 6.5% of all patients who underwent percutaneous MWA and in 12.2% of patients who underwent open MWA.

CONCLUSIONS

This review showed that MWA can be effective in achieving analgesia for up to 6 months in select cases, although most procedures were performed in combination with augmentation and/or open surgery. Local tumor control was additionally successful in most patients, suggestive of a potential curative role for MWA.

Epidemiology of spinal cord and column tumors

The spine is a frequent location for metastatic disease. As local control of primary tumor pathology continues to improve, survival rates improve and, by extension, the opportunity for metastasis increases. Breast, lung, and prostate cancer are the leading contributors to spinal metastases. Spinal metastases can manifest as bone pain, pathologic fractures, spinal instability, nerve root compression, and, in its most severe form, spinal cord compression. The global extent of disease, the spinal burden, neurologic status, and life expectancy help to categorize patients as to their candidacy for treatment options. Efficient identification and workup of those with spinal metastases will expedite the treatment cascade and improve quality of life.

Kyphoplasty in the treatment of occult and non-occult metastatic vertebral tumors

To compare the efficacy and safety of kyphoplasty (KP) in the treatment of occult metastatic vertebral tumors (OMVT) and non-occult metastatic vertebral tumors (MVT).From January 2013 to December 2017, 65 cases of occult metastatic vertebral tumors and 82 cases of metastatic vertebral tumors were selected and divided into 2 groups. After KP, they were followed up by a year of outpatient visits and telephone calls. The visual analogue scale (VAS) and Oswestry disability index (ODI) scores, the amount of bone cement injected, the change of vertebral height and the incidence of complications were recorded, compared and analyzed by SPSS software. t test was used to compare the differences between the same group of patients at different times and between the 2 groups of patients.In the OMVT group, the operation time was 24.52 ± 4.24 minutes, the fluoroscopy time was 10.18 ± 1.53 minutes and the volume of bone cement was 3.62 ± 0.93 ml. The VAS score decreased from 7.26 ± 01.08 preoperatively to 2.77 ± 0.93 postoperatively (P < .01). The ODI score decreased from 64.89 ± 9.05 preoperatively to 25.82 ± 4.63 postoperatively (P < .01). In the MVT group, the operation time was 26.63 ± 4.61 minutes, the fluoroscopy time was 11.04 ± 2.15 minutes and the volume of bone cement was 4.09 ± 1.10 ml. The VAS score decreased from 7.73 ± 0.94 preoperatively to 3.22 ± 0.80 postoperatively (P < .01). The ODI score decreased from 69.20 ± 7.14 preoperatively to 28.02 ± 4.40 postoperatively (P < .01). The vertebral height of MVT patients was significantly improved after operation (P < .01), but there was no difference in OMVT patients (P > .05).Occult metastatic vertebral tumors can be detected by Magnetic Resonance Imaging (MRI), and KP may be more effective and safer in the treatment of OMVT.