Update on Preoperative Embolization of Bone Metastases

A study on short-term efficacy and safety of Iodine-125 brachytherapy coupled with preoperative arterial chemoembolization for hypervascular spinal metastasis

PURPOSE

Hypervascular spinal metastatic malignancies can cause severe pain and intraoperative bleeding and selection of appropriate treatment can be challenging. This study aimed to observe the short-term efficacy and safety of Iodine-125 brachytherapy (125I BT) combined with preoperative transcatheter arterial chemoembolization (TACE) for hypervascular spinal metastasis.

METHODS

This study included a total of 33 patients (39 lesions) with hypervascular spinal metastasis. All of them carried out a regimen of TACE followed by 125I BT under CT guidance. A brachytherapy planning system has been utilized for the purpose of designing treatment plans and optimizing dose distribution. Pain relief was evaluated using a numeric rating scale (NRS) and intraoperative bleeding was recorded. Follow-up was conducted for 6 months to observe the local control rate and clinical complications.

RESULTS

All patients tolerated combined treatment well and intraoperative blood loss of every patient was not more than 10 ml. The 2- and 6- month local disease control rates were 92.3% and 83.8%. The NRS scores for thirty-three tumor patients before surgery and after one week, two, and six months of surgery were recorded as 7.33 ± 1.80, 7.39 ± 1.89, 3.15 ± 2.35, and 4.16 ± 2.15, respectively. The NRS score 2 months after treatment was found considerably lower in comparison to the NRS score before operation (p < 0.05).

CONCLUSIONS

According to our findings, 125I BT as well as preoperative TACE leads to perioperative hemostasis, pain alleviation, and reduced tumor burden, indicating that this combined treatment could be effective and promising for hypervascular spinal metastases.

The effect of timing between preoperative embolization and surgery: A retrospective analysis of hypervascular bone metastases

BACKGROUND AND OBJECTIVES

The optimal timing between preoperative embolization of hypervascular metastatic bone lesions and surgery has yet to be established. Our analysis sought to evaluate embolization timing impacts blood loss, transfusion risk, and operative time in patients with hypervascular primary tumors.

METHODS

We identified patients with renal cell (RCC) or thyroid carcinoma undergoing surgery between 1992 and 2023. Patients were segregated into the following cohorts: (1) no embolization preoperatively, (2) surgery <24 h of embolization, and (3) surgery >24 h after embolization. Multivariate logistic regression analyses were performed to assess the effect of embolization timing while controlling for confounding variables.

RESULTS

No differences were seen in all evaluated outcomes between immediate and delayed embolization cohorts. No differences in estimated blood loss were seen between the immediate (OR: 0.685, 95% CI: 0.159-2.949; p = 0.611) and delayed (OR: 0.568, 95% CI: 0.093-3.462; p = 0.539) surgery cohorts compared with patients without embolization. Surgery >24 h after embolization was not associated with a higher risk of prolonged operative time (OR: 13.499, 95% CI: 0.832-219.146; p = 0.067).

CONCLUSIONS

These findings suggest that surgery may be safely delayed beyond 24 h from embolization without a higher risk of bleeding. In appropriately selected cohorts, embolization may not be needed preoperatively.

Vascular Interventions in Oncology

Vascular interventions are an important and established tool in the management of the oncology patient. The goal of these procedures may be curative, palliative or adjunctive in nature. Some of the common vascular interventions used in oncology include transarterial embolisation or chemoembolisation, selective internal radiation therapy, chemosaturation, venous access lines, superior vena cava stenting and portal vein embolisation. We provide an overview of the principles, technology and approach of vascular techniques for tumour therapy in both the arterial and venous systems. Arterial interventions are currently mainly used in the management of hepatocellular carcinoma. Transarterial embolisation, chemoembolisation and selective internal radiation therapy deliver targeted catheter-delivered treatments with the aim of reducing tumour burden, controlling tumour growth or increasing survival in patients not eligible for transplantation. Chemosaturation is a regional chemotherapy technique that delivers high doses of chemotherapy directly to the liver via the hepatic artery, while reducing the risks of systemic effects. Venous interventions are more adjunctive in nature. Venous access lines are used to provide a means of delivering chemotherapy and other medications directly into the bloodstream. Superior vena cava stenting is a palliative procedure that is used to relieve symptoms of superior vena cava obstruction. Portal vein embolisation is a procedure that allows hypertrophy of a healthy portion of the liver in preparation for liver resection. Interventional radiology-led vascular interventions play an essential part of cancer management. These procedures are minimally invasive and provide a safe and effective adjunct to traditional cancer treatment methods. Appropriate work-up and discussion of each patient-specific problem in a multidisciplinary setting with interventional radiology is essential to provide optimum patient-centred care.

Neoadjuvant Arterial Embolization of Spine Metastases Associated With Improved Local Control in Patients Receiving Surgical Decompression and Stereotactic Body Radiotherapy

BACKGROUND

Spine metastases often cause significant pain, instability, and/or neurological morbidity. Local control (LC) of spine metastases has been augmented with advances in systemic therapies, radiation, and surgical technique. Prior reports suggest an association between preoperative arterial embolization and improved LC and palliative pain control.

OBJECTIVE

To further elucidate the role of neoadjuvant embolization on LC of spine metastases and the potential for improved pain control in patients receiving surgery and stereotactic body radiotherapy (SBRT).

METHOD

A retrospective single-center review between 2012 and 2020 identified 117 patients with spinal metastases from various solid tumor malignancies managed with surgery and adjuvant SBRT with or without preoperative spinal arterial embolization. Demographic information, radiographic studies, treatment characteristics, Karnofsky Performance Score, Defensive Veterans Pain Rating Scale, and mean daily doses of analgesic medications were reviewed. LC was assessed using magnetic resonance imaging obtained at a median 3-month interval and defined as progression at the surgically treated vertebral level.

RESULTS

Of 117 patients, 47 (40.2%) underwent preoperative embolization, followed by surgery and SBRT and 70 (59.8%) underwent surgery and SBRT alone. Within the embolization cohort, the median LC was 14.2 months compared with 6.3 months among the nonembolization cohort ( P = .0434). Receiver operating characteristic analysis suggests ≥82.5% embolization predicted significantly improved LC (area under the curve = 0.808; P < .0001). Defensive Veterans Pain Rating Scale mean and maximum scores significantly decreased immediately after embolization ( P < .001).

CONCLUSION

Preoperative embolization was associated with improved LC and pain control suggesting a novel role for its use. Additional prospective study is warranted.

Spinal tumor embolization: benefit for surgical resection

The embolization of hypervascular spinal tumors preoperatively has shown to be a worthwhile adjunctive procedure to minimize the elevated risks associated with surgical resection, such as intraoperative blood loss and its associated complications. Resection of these hypervascular tumors is necessary for local tumor control, reduction in patient-reported pain, improved neurological functioning, and spinal stability. This adjunctive procedure has been associated with improved surgical outcomes and easier facilitation of surgical resection. As such, we provide a review of the current literature examining the employment of this technique. Specifically, this article (a) reviews the techniques of embolization, with anatomical considerations of the arterial framework of the spinal network; (b) relativizes and outlines the post-embolization management of spinal tumor resection; (c) provides a critical outlook on the reported benefit of preoperative embolization before surgical resection with support from clinical studies in the literature; and (d) discusses the efficacy and reliability of provocative testing and post-procedural management and follow-up. Ultimately, a thorough and updated review of preoperative spinal tumor embolization and its clinical benefits will summarize the current fund of knowledge and encourage future research toward continued improvements in patient outcomes for those needing to undergo surgical resection of spinal lesions.

Palliative Arterial Embolization for Metastases of the Sternum

BACKGROUND

To investigate the safety and efficacy of palliative arterial embolization for metastases of the sternum.

MATERIALS AND METHODS

This study included 10 consecutive patients (5 M, 5 F; mean age 58.1; range 37-70) with metastases of the sternum from different primary tumors, treated with palliative arterial embolization using NBCA-Lipiodol between January 2007 and June 2022. Four patients received a second embolization at the same site, for a total of 14 embolizations. Data on technical and clinical success, as well as changes in tumor size, were collected. All embolization-related complications were evaluated according to the CIRSE classification system for complications.

RESULTS

Post-embolization angiography showed occlusion of more than 90% of the pathological feeding vessels in all procedures. Pain score and analgesic drug consumption were reduced by 50% in all 10 patients (100%, p < 0.05). The mean duration of pain relief was 9.5 months (range 8 to 12 months, p < 0.05). Metastatic tumor size was reduced from a mean of 71.5 cm³ (range 41.6 to 90.3 cm³) pre-embolization to a mean of 67.9 cm³ (range 38.5 to 86.1 cm³) at the 12-month follow-up (p < 0.05). None of the patients experienced embolization-related complications.

CONCLUSION

Arterial embolization is safe and effective as a palliative treatment for patients with metastases of the sternum who did not benefit from radiation therapy or experienced recurrence in symptoms.

Preoperative Arterial Embolization of Musculoskeletal Tumors: A Tertiary Center Experience

The purpose of this study was to report the effectiveness of preoperative transcatheter arterial embolization (TAE) of musculoskeletal tumors in terms of blood loss and functional outcomes. Patients who underwent preoperative TAE of hypervascular musculoskeletal tumors between January 2018 and December 2021 were retrospectively included. The patients' characteristics, TAE procedure details, degree of post-TAE devascularization, surgical outcomes in terms of red blood cell transfusion and functional results were collected. The degree of devascularization was compared between patients who had peri-operative transfusion and those who did not. Thirty-one patients were included. The 31 TAE procedures led to complete (58%) or near-complete (42%) tumor devascularization. Twenty-two patients (71%) had no blood transfusion during surgery. Nine patients (29%) had a blood transfusion, with a median number of red blood cell packs of three (q1, 2; q3, 4; range: 1-4). Eight patients (27%) had complete improvement of the initial musculoskeletal symptoms at the end of the follow-up, 15 (50%) had partially satisfying improvement, 4 (13%) had partially unsatisfying improvement and 3 (10%) had no improvement. Our study suggests that preoperative TAE of hypervascular musculoskeletal tumors allowed for bloodless surgery in 71% of patients and minimal transfusion needs for the remaining 29%.

Transarterial Embolization of Bone Metastases

Embolization of bone metastases is most commonly performed for hypervascular tumors prior to surgical resection. When employed in this fashion embolization can significantly decrease perioperative hemorrhage and improve surgical outcomes. In addition, embolization of bone metastases may lead to local tumor control and decreased tumoral associate bone pain. Careful techniques and choice of embolic material are required when performing embolization of bone lesions to ensure low procedural complications and high rates of clinical success.⁴ The indications, technical considerations, and complications associated with embolization of metastatic hypervascular bone lesions will be discussed in this review with subsequent case examples.

Preoperative embolization in the treatment of patients with metastatic epidural spinal cord compression: A retrospective analysis

Purpose

The purpose of the study was to assess the effectiveness and safety of preoperative embolization in the treatment of patients with metastatic epidural spinal cord compression (MESCC).

Methods

A retrospective analysis of 138 MESCC patients who underwent decompressive surgery and spine stabilization was performed in a large teaching hospital. Among all enrolled patients, 46 patients were treated with preoperative embolization (the embolization group), whereas 92 patients did not (the control group). Patient's baseline clinical characteristics, surgery-related characteristics, and postoperative neurological status, complications, and survival prognoses were collected and analyzed. Subgroup analysis was performed according to the degree of tumor vascularity between patients with and without preoperative embolization.

Results

Patients with severe hypervascularity experienced more mean blood loss in the control group than in the embolization group, and this difference was statistically significant (P=0.02). The number of transfused packed red cells (PRC) showed a similar trend (P=0.01). However, for patients with mild and moderate hypervascularity, both blood loss and the number of PRC transfusion were comparable across the two groups. Regarding decompressive techniques, the embolization group (64.29%, 9/14) had a higher proportion of circumferential decompression in comparison to the control group (30.00%, 9/30) among patients with severe hypervascularity (P=0.03), whereas the rates were similar among patients with mild (P=0.45) and moderate (P=0.54) hypervascularity. In addition, no subgroup analysis revealed any statistically significant differences in operation time, postoperative functional recovery, postoperative complications, or survival outcome. Multivariate analysis showed that higher tumor vascularity (OR[odds ratio]=3.69, 95% CI [confident interval]: 1.30-10.43, P=0.01) and smaller extent of embolization (OR=4.16, 95% CI: 1.10-15.74, P=0.04) were significantly associated with more blood loss.

Conclusions

Preoperative embolization is an effective and safe method in treating MESCC patients with severe hypervascular tumors in terms of intra-operative blood loss and surgical removal of metastatic tumors. Preoperative tumor vascularity and extent of embolization are independent risk factors for blood loss during surgery. This study implies that MESCC patients with severe hypervascular tumors should be advised to undergo preoperative embolization.

Percutaneous transforaminal endoscopic decompression combined with percutaneous vertebroplasty in treatment of lumbar vertebral body metastases: A case report

BACKGROUND

Percutaneous endoscopic lumbar discectomy (PTED) is a procedure that is commonly used to treat lumbar disc herniation and spinal stenosis. Despite its less invasiveness, this surgery is rarely used to treat spinal metastases. Percutaneous vertebroplasty (PVP) has been utilized to treat lumbar vertebral body metastases but it has not proven useful in treating sciatic patients.

CASE SUMMARY

A 68-year-old woman presented with low back pain and radicular symptoms. She couldn't straighten her legs because of severe pain. Computed tomography (CT) showed a mass lesion in the lung and bone destruction in the L4 vertebrae. The biopsy of the lung lesion revealed adenocarcinoma and the biopsy for L4 vertebrae revealed metastatic adenocarcinoma. PTED paired with PVP was performed on the patient due to the patient's poor overall physical state and short survival time. Transcatheter arterial embolization of vertebral tumors was performed before surgical resection to reduce excessive blood loss during the operation. The incision was scaled up with the TESSY technology. The pain was obviously relieved following the operation and no serious complications occurred. Postoperative CT showed that the decompression around the nerve root was successful, polymethyl methacrylate filling was satisfactory and the tumor tissue around the nerve root was obviously removed. During the 1-year follow-up period, the patient was in a stable condition.

CONCLUSION

PTED in combination with PVP is an effective and safe treatment for Lumbar single-level Spinal Column metastases with radicular symptoms. Because of the small sample size and short follow-up time, the long-term clinical efficacy of this method needs to be further confirmed.

Trends in Diagnosis and Surgical Treatment of Bone Metastases among Orthopedic Surgeons

Background: The proper diagnosis and treatment of bone metastases are essential for patient survival. However, several strategies for the treatment are practiced. Therefore, the aim of the study was to analyze what factors influence the choice of a method of treatment. Methods: An online survey was conducted within the Polish Society of Orthopedics and Traumatology. It consisted of 45 questions and was divided into four main parts: Participant Characteristics, Diagnosis and Qualification, Treatment, and Clinical Cases. Results: A total number of 104 responses were collected. The most frequently chosen methods were: Intramedullary nail (IMN) + Resection + Polymethyl methacrylate (PMMA) (30.47%) and IMN without tumor resection (42.13%), and in third place, modular endoprosthesis (17.25%). The less experienced group of orthopedic surgeons more often (47.5% vs. 39.5%) decided to perform IMN without tumor resection than the more experienced group (p = 0.046). Surgeons from district hospitals less frequently (13.7% vs. 23.1%) would decide to use modular endoprosthesis than surgeons from university hospitals (p = 0.000076). Orthopedists who performed ≥ 11 bone metastases surgeries per year would more often use modular endoprosthesis (34.8% vs. 13.2%) than those who performed ≤ 10 operations per year (p = 0.000114). Conclusion: Experience, place of work, and the number of metastasis surgeries performed during a year may influence the choice of treatment method in patients with bone metastases.

Treatment of Metastatic Spinal Disease; what the Radiologist needs to know

Advancements in technology and multidisciplinary management have revolutionized the treatment of spinal metastases. Imaging plays a pivotal role in determining the treatment course for spinal metastases. This article aims to review the relevant imaging findings in spinal metastases from the perspective of the treating clinician, describe the various treatment options, and discuss factors influencing choice for each available treatment option. Cases that once required radical surgical resection or low-dose conventional external beam radiation therapy, or both, are now being managed with separation surgery, spine stereotactic radiosurgery/stereotactic body radiation therapy, or both, with decreased morbidity, improved local control, and more durable pain control. The primary focus in determining treatment choice is now on tumor control outcomes, treatment-related morbidity, and quality of life.

Expanding the role of interventional oncology for advancing precision immunotherapy of solid tumors

Adoptive cell therapy with chimeric antigen receptors (CAR) T cells has proven effective for hematologic malignancies, but success in solid tumors has been impeded by poor intratumoral infiltration, exhaustion of effector cells from antigen burden, and an immunosuppressive tumor microenvironment. Results from recent clinical trials and preclinical studies lend promising evidence of locoregional approaches for CAR T cell delivery, priming the tumor microenvironment, and performing adjuvant therapies that sustain T cell activity. Interventional oncology is a subspeciality of interventional radiology where imaging guidance is used to perform percutaneous and catheter-directed procedures for localized, non-surgical therapy or interrogation of solid tumors. Interventional oncology provides unique synergies with immunotherapy, which has been well-studied to improve treatment efficacy while reducing toxicities associated with systemic treatment. Besides aiding in CAR T cell delivery, priming, or the stimulation of the tumor microenvironment to promote effector survival and function, interventional oncology can also aid in the monitoring of treatment response through selective, multiplex tumor sampling and catheter-based venous sampling. This review presents an overview of interventional oncology, its various procedures, and its potential for advancing CAR T cell immunotherapy of solid tumors.

Scheduling surgery after transarterial embolization: does timing make any difference to intraoperative blood loss for renal cell carcinoma bone metastases?

PURPOSE

Our purpose is to clarify the optimal timing of surgery after transarterial embolization (TAE) for renal cell carcinoma (RCC) bone metastases.

METHODS

This retrospective study included 41 patients with RCC bone metastases embolized between 2013 and 2019. Different-sized particulate and/or liquid embolic agents were used for TAE. Embolizations were categorized into groups 1-3 according to the interval between TAE and surgery (group 1: <1 day, group 2: 1-3 days, group 3: >3 days). Degree of embolization after TAE was graded visually based on angiographic images (<50%, 50%-75%, 75%-90%, >90%). The relationship between the TAE-surgery interval and intraoperative blood loss (IBL) and the correlation between IBL and embolization grade were examined. Lesion sizes and the relationships among lesion localizations and contrast media usage, intervention time, and IBL were also analyzed.

RESULTS

Forty-six pre-operative TAEs (single lesion at each session) were performed in this study (26 in group 1, 13 in group 2, 7 in group 3). Lesion sizes and distributions were similar between groups (p = 0.897); >75% devascularization was achieved in 40 (TAEs 86.96%), but the IBL showed no correlation with the embolization rate (r=0.032, p = 0.831). The TAE-surgery interval was 1-7 days. The median IBL in group 1 (750 mL; range, 150-3000 mL) was significantly lower than those in the other groups (p = 0.002). Contrast media usage (p = 0.482) and intervention times (p = 0.261) were similar for metastases at different localizations. IBL values after TAE were lower for extremity metastases (p = 0.003).

CONCLUSION

Bone metastases of RCC are well-vascularized, and to achieve lowest IBL values, surgery should preferably be performed <1 day after TAE.

[Treatment strategies for tumor-related pathological fractures of the extremities]

Pathological fractures of the extremities frequently lead to uncertainty with respect to the treatment strategy and timing. The origin of metastases is typically breast, bronchial, renal and prostate cancer and myelomas. Primary bone tumors play a subordinate role. The majority affect the femur, humerus and occasionally the tibia. Surgery is typically the first line treatment as healing under conservative treatment is unlikely. The most important goal is to relieve pain and the preservation or restoration of function. For correct assessment of indications, analysis of the fracture pattern and oncological aspects including dignity, entity, prognosis, metastatic status and the general condition of the patient need to be taken into consideration. Based on all these aspects the surgical approach can be chosen. Treatment options range from osteosynthetic stabilization and augmentation osteosynthesis up to endoprosthesis replacement. The treatment is carried out in an interdisciplinary procedure as additional measures need to be addressed in addition to the surgical treatment.

The role of percutaneous transarterial embolization in the management of spinal bone tumors: a literature review

PURPOSE

Spinal bone tumors include a heterogeneous broad of primary or metastatic lesions that may present as incidental findings or manifest with painful symptoms and pathological fractures. Optimal management of spine bone lesions is often difficult and treatment algorithms are usually solidly based on surgery. We aimed to evaluate the contribution of trans-arterial embolization in this field, with particular attention to the procedure efficacy, technical difficulties and complications.

METHODS

We present a literature review on the role of trans-arterial embolization in the management of spinal bone tumors, both primary and metastatic, evaluating its contribution as preoperative treatment, palliative procedure and standalone curative strategy.

RESULTS

Trans-arterial embolization provides an important contribution to reducing surgery hemorrhagic risks, offering a better visualization of the operating field, and possibly increasing tumor susceptibility to chemotherapy or radiation therapy. Nonetheless, it plays an important part in pain palliation, with the unquestionable advantage of being easily repeatable in case of necessity. Its curative role as a standalone therapy is still subject of debate, and at the present time, satisfactory results have been recorded only in the treatment of aneurysmal bone cysts.

CONCLUSION

Percutaneous trans-arterial embolization has established as a highly useful minimally invasive procedure in the management of spinal bone lesions, particularly as adjuvant preoperative therapy and palliative treatment.

[Strategic approach to pathological fractures]

Pathological tumor-associated fractures are overall rare. They can occur in every age group and every bone. Although tumor-related fractures only form a small proportion of bone fractures, the early recognition of the cause of the fracture and treatment according to oncological guidelines are of enormous importance for affected patients. False treatment is frequently associated with far-reaching negative consequences with respect to the course of the disease. The great challenge is not the expeditious surgical treatment but much more the adequate diagnostics and the incorporation of local fracture treatment into an interdisciplinary overall oncological concept.

Preoperative cryoablation of a hypervascular bone metastasis: A case of effective devascularization before preoperative embolization

Image-guided cryoablation has become a common approach for the palliative treatment of painful metastatic bone lesions, and indications for this procedure have expanded to include local control of bone metastases. We report a case in which cryoablation was performed on a large hypervascular renal cell carcinoma bone metastasis before surgical fixation of an impending fracture. In this case, cryoablation reduced the patient's pain but also appeared to result in devascularization of the tumor, thus obviating the need for preoperative embolization. This case raises the possibility that image-guided cryoablation may represent an alternative to preoperative embolization for vascular tumors while also serving a palliative function.

Image-guided Cryotherapy for Musculoskeletal Tumors

BACKGROUND

This article represents a review of the use of image-guided cryotherapy in the treatment of musculoskeletal tumor lesions. Cryotherapy is able to induce a lethal effect on cancer cells through direct and indirect mechanisms. In this manuscript, we combined our experience with that of other authors who have published on this topic in order to provide indications on when to use cryotherapy in musculoskeletal oncology.

DISCUSSION

Image-Guided percutaneous cryotherapy is a therapeutic method now widely accepted in the treatment of patients with musculoskeletal tumors. It can be used both for palliative treatments of metastatic bone lesions and for the curative treatment of benign bone tumors, such as osteoid osteoma or osteoblastoma. In the treatment of bone metastases, cryotherapy plays a major role in alleviating or resolving disease-related pain, but it has also been demonstrated that it can have a role in local disease control. In recent years, the use of cryotherapy has also expanded for the treatment of both benign and malignant soft tissue tumors.

CONCLUSION

Percutaneous cryotherapy can be considered a safe and effective technique in the treatment of benign and malignant musculoskeletal tumors. Cryotherapy can be considered the first option in benign tumor lesions, such as osteoid osteoma, and a valid alternative to radiofrequency ablation. In the treatment of painful bone metastases, it must be considered secondarily to other standard treatments (radiotherapy, bisphosphonate therapy, and chemotherapy) when they are no longer effective in controlling the disease or when they cannot be repeated (for example, radiotherapy).