Efficacy Analysis of Separation Surgery Combined with SBRT for Spinal Metastases-A Long-Term Follow-Up Study Based on Patients with Spinal Metastatic Tumor in a Single-Center

Earlier Radiation Is Associated with Improved 1-Year Survival After Metastatic Spine Tumor Surgery

OBJECTIVE

In patients undergoing metastatic spine surgery, we sought to 1) report time to postoperative radiation therapy (RT), 2) describe the predictive factors of time to postoperative RT, and 3) determine if earlier postoperative RT is associated with improved local recurrence (LR) and overall survival (OS).

METHODS

A single-center retrospective cohort study was undertaken of all patients undergoing spine surgery for extradural metastatic disease and receiving RT within 3 months postoperatively between January 2010 and January 2021. Time to postoperative RT was dichotomized at <1 month versus 1-3 months. The primary outcomes were LR, OS, and 1-year survival. Secondary outcomes were wound complication, Karnofsky Performance Status, and modified McCormick Scale (MMS) score. Regression analyses controlled for age, body mass index, tumor size, preoperative RT, preoperative/postoperative chemotherapy, and type of RT.

RESULTS

Of 76 patients undergoing spinal metastasis surgery and receiving postoperative RT within 3 months, 34 (44.7%) received RT within 1 month and 42 (55.2%) within 1-3 months. Patients with larger tumor size (β = -3.58; 95% confidence interval [CI], -6.59 to -0.57; P = 0.021) or new neurologic deficits (β = -16.21; 95% CI, -32.21 to -0.210; P = 0.047) had a shorter time to RT. No significant association was found between time to RT and LR or OS on multivariable logistic/Cox regression. However, patients who received RT between 1 and 3 months had a lower odds of 1-year survival compared with those receiving RT within 1 month (odds ratio, 0.18; 95% CI, 0.04-0.74; P = 0.022). Receiving RT within 1 month versus 1-3 months was not associated with wound complications (7.1% vs. 2.9%; P = 0.556) (odds ratio, 4.40; 95% CI, 0.40-118.0; P = 0.266) or Karnofsky Performance Status/modified McCormick Scale score.

CONCLUSIONS

Spine surgeons, oncologists, and radiation oncologists should make every effort to start RT within 1 month to improve 1-year survival after metastatic spine tumor surgery.

A new era in the management of spinal metastasis

Despite the recent advances in cancer treatment, the incidence of patients with spinal metastases continues to grow along with the total number of cancer patients. Spinal metastases can significantly impair activities of daily living (ADL) and quality of life (QOL), compared with other types of bone metastases, as they are characterized with severe pain and paralysis caused by skeletal-related events. Reduced ADL can also lead to treatment limitations as certain anticancer agents and radiation therapy are not compatible treatments; thus, leading to a shorter life expectancy. Consequently, maintaining ADLs in patients with spinal metastases is paramount, and spine surgeons have an integral role to play in this regard. However, neurosurgeon, orthopedic and spinal surgeons in Japan do not have a proactive treatment approach to spinal metastases, which may prevent them from providing appropriate treatment when needed (clinical inertia). To overcome such endemic inertia, it is essential for 1) spine surgeons to understand and be more actively involved with patients with musculoskeletal disorders (cancer locomo) and cancer patients; 2) the adoption of a multidisciplinary approach (coordination and meetings not only with the attending oncologist but also with spine surgeons, radiologists, rehabilitation specialists, and other professionals) to preemptive treatment such as medication, radiotherapy, and surgical treatment; and 3) the integration of the latest findings associated with minimally invasive spinal treatments that have expanded the indications for treatment of spinal metastases and improved treatment outcomes. This heralds a new era in the management of spinal metastases.

Treatment progress of spinal metastatic cancer: a powerful tool for improving the quality of life of the patients

Spinal metastasis is a common secondary malignant tumor of the bone, often resulting in spinal cord and nerve root compression, leading to obvious pain and related compression symptoms. This condition has a high incidence and mortality rate. The treatment approach for most patients with spinal metastasis is primarily palliative. Consultation with a multidisciplinary team is widely accepted as a comprehensive treatment approach for patients with spinal metastases. With advancements in research and technology, the evaluation and treatment of spinal metastatic cancer are continuously evolving. This study provides an overview of surgical treatment, minimally invasive treatment, and radiotherapy for spinal metastatic cancer and also analyzes the clinical effects, advantages, and current limitations associated with various treatment approaches.

Stereotactic Body Radiation Therapy for Spinal Metastases: Benefits and Limitations

Progress in biological cancer characterization, targeted systemic therapies and multimodality treatment strategies have shifted the goals of radiotherapy for spinal metastases from short-term palliation to long-term symptom control and prevention of compilations. This article gives an overview of the spine stereotactic body radiotherapy (SBRT) methodology and clinical results of SBRT in cancer patients with painful vertebral metastases, metastatic spinal cord compression, oligometastatic disease and in a reirradiation situation. Outcomes after dose-intensified SBRT are compared with results of conventional radiotherapy and patient selection criteria will be discussed. Though rates of severe toxicity after spinal SBRT are low, strategies to minimize the risk of vertebral compression fracture, radiation induced myelopathy, plexopathy and myositis are summarized, to optimize the use of SBRT in multidisciplinary management of vertebral metastases.

Hybrid Therapy Versus Total En Bloc Spondyectomy in the Treatment of Solitary Radioresistant Spinal Metastases: A Single-center, Retrospective Study

STUDY DESIGN

This was a retrospective study.

OBJECTIVE

To compare the treatment efficacy of hybrid therapy (HT) with that of total en bloc spondylectomy (TES) in patients with solitary radioresistant high-grade epidural spinal cord compression (ESCC) spinal metastases.

SUMMARY OF BACKGROUND DATA

Both HT and TES can yield good results for solitary radioresistant metastatic spinal tumors with high-grade ESCC. However, there is still a lack of comparative studies on the treatment efficacy of these 2 methods.

MATERIALS AND METHODS

We retrospectively reviewed patients with the above-mentioned tumors between January 2012 and May 2019. A total of 157 patients underwent surgery, 64 of whom received HT and 93 were treated with TES. Propensity score matching (1:1 ratio) allowed the generation of best-matched pairs for the 2 categories. Local control rates and survival rates were estimated using the Kaplan-Meier method.

RESULTS

All patients had a minimum 2-year follow-up. The longest follow-up period was 88 months. The survival rates and local progression-free survival rates after HT were comparable with those after TES at 1 year (84.6% vs. 83.1% and 90.2% vs. 90%, respectively), 2 years (60.8% vs. 64.3% and 64.1% vs. 62.1%, respectively), and 5 years (18.8% vs. 24.1% and 24.4% vs. 28.4%, respectively). There were no significant differences in pain control, improvement in neurological status, spine stabilization restoration, incidence of perioperative complications, and improvement in quality of life between the groups. However, HT showed more advantages than TES in that it had a shorter operative time and lower intraoperative blood loss.

CONCLUSIONS

HT can obtain satisfactory results comparable to TES for solitary radioresistant metastatic spinal tumors with high-grade ESCC. In addition, HT has a shorter operative time and fewer perioperative complications than TES. HT may be a promising treatment for solitary radioresistant metastatic spinal tumors with high-grade ESCC.

Predictive factors, preventive implications, and personalized surgical strategies for bone metastasis from lung cancer: population-based approach with a comprehensive cancer center-based study

Background

Bone metastasis (BM) and skeletal-related events (SREs) happen to advanced lung cancer (LC) patients without warning. LC-BM patients are often passive to BM diagnosis and surgical treatment. It is necessary to guide the diagnosis and treatment paradigm for LC-BM patients from reactive medicine toward predictive, preventive, and personalized medicine (PPPM) step by step.

Methods

Two independent study cohorts including LC-BM patients were analyzed, including the Surveillance, Epidemiology, and End Results (SEER) cohort (n = 203942) and the prospective Fudan University Shanghai Cancer Center (FUSCC) cohort (n = 59). The epidemiological trends of BM in LC patients were depicted. Risk factors for BM were identified using a multivariable logistic regression model. An individualized nomogram was developed for BM risk stratification. Personalized surgical strategies and perioperative care were described for FUSCC cohort.

Results

The BM incidence rate in LC patients grew (from 17.53% in 2010 to 19.05% in 2016). Liver metastasis was a significant risk factor for BM (OR = 4.53, 95% CI = 4.38-4.69) and poor prognosis (HR = 1.29, 95% CI = 1.25-1.32). The individualized nomogram exhibited good predictive performance for BM risk stratification (AUC = 0.784, 95%CI = 0.781-0.786). Younger patients, males, patients with high invasive LC, and patients with other distant site metastases should be prioritized for BM prevention. Spine is the most common site of BM, causing back pain (91.5%), pathological vertebral fracture (27.1%), and difficult walking (25.4%). Spinal surgery with personalized spinal reconstruction significantly relieved pain and improved daily activities. Perioperative inflammation, immune, and nutrition abnormities warrant personalized managements. Radiotherapy needs to be recommended for specific postoperative individuals.

Conclusions

The presence of liver metastasis is a strong predictor of LC-BM. It is recommended to take proactive measures to prevent BM and its SREs, particularly in young patients, males, high invasive LC, and LC with liver metastasis. BM surgery and perioperative management are personalized and required. In addition, adjuvant radiation following separation surgery must also be included in PPPM-guided management.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-022-00270-9.

10-Year Trends in the Surgical Management of Patients with Spinal Metastases: A Scoping Review

BACKGROUND

Spinal metastases are present in approximately 20% of patients with cancer, giving a risk for neurologic dysfunction and instability. In already frail patients, surgeons strive to improve quality of life. Our goal was to review a 10-year trend in the surgical management of spinal metastases.

METHODS

A scoping review was performed systematically using PubMed to assess trends in surgical treatment for spinal metastases. The search terms used were: metastas∗, "neoplasm metastasis"[Mesh], "Spine"[Mesh], spine, spinal, "vertebral column," "vertebral body," laser, robot, radiofrequency, screws, fixation, "separation surgery," corpectomy, vertebrectomy, spondylectomy, vertebroplasty, kyphoplasty, surgery, "open surgery," "mini open surgery," "minimally invasive surgery," endoscopy, thoracoscopy, corpectom∗, vertebrectom∗, spondylectom∗, "en bloc," and MIS. The variables of interest were neurologic improvement, tumor recurrence, reoperation, and overall survival.

RESULTS

A total of 2132 articles were found within the primary query. Fifty-six studies were selected for final review. The results were organized into main surgical practices: decompression, mechanical stabilization, and pain management. For separation surgery, clinical outcomes were overall 1-year survival, 40.7%-78.4%; recurrence rate, 4.3%-22%; reoperation, 5%; and complications, 5.4%-14%. For corpectomy, clinical outcomes were overall 1-year survival, 30%-92%; reoperation, 1.1%-50%; and recurrence rate, of 1.1%-28%. Complications and reoperations with spinal instrumentation were 0%-13.6% and 0%-15%, respectively. Cement augmentation achieved pain reduction rates of 56%-100%, neurologic improvement/stability 84%-100%, and complication rates 6%-56%. Laser achieved local tumor control rate of 71%-82% at 1 year follow-up, reoperation rate of 15%-31%, and complication rate of 5%-26%.

CONCLUSIONS

Minimally invasive techniques for decompression and stabilization seem to be the preferred method to surgically treat metastatic spine disease, with good outcomes. More research with high level of evidence is required to support the long-term outcomes of these approaches.

Separation Surgery in the Treatment of Spinal Metastasis

The life expectancy of patients with advanced cancer has been prolonged with the development of systemic treatment technology. Spinal metastasis is one of the common ways of metastasis of advanced tumors, leading to spinal cord compression and compression fractures, which often lead to a significant reduction in patients’ quality of life and physical function. Therefore, surgical treatment is still needed for functional recovery and local control. Separation surgery has been known since 2014 when it was purposed. Combined with radiotherapy, it can achieve an ideal goal of local control. This paper gives a brief introduction to separation surgery, hoping to increase the reader's understanding and consider this method in the course of treatment.

A systematic review of MIS and open decompression surgery for spinal metastases in the last two decades

OBJECTIVE

The primary intention of this review being to produce an updated systematic review of the literature on published outcomes of decompressive surgery for metastatic spinal disease including metastatic spinal cord compression, using techniques of MIS and open decompressive surgery.

METHODS

The authors conducted database searches of OVID MEDLINE and EMBASE identifying those studies that reported clinical outcomes, surgical techniques used along with associated complications when decompressive surgery was employed for metastatic spinal tumors. Both retrospective and prospective studies were analysed. Articles were assessed to ensure the required inclusion criteria was met. Articles were then categorised and tabulated based on the following reported outcomes: predictors of survival, predictors of ambulation or motor function, surgical technique, neurological function, and miscellaneous outcomes.

RESULTS

2654 citations were retrieved from databases, of these 31 met the inclusion criteria. 5 studies were prospective, the remaining 26 were retrospective. Publication years ranged from 2000 to 2020. Study size ranged from 30 to 914 patients. The most common primary tumors identified were lungs, breast, prostate and renal cancers. One study ( Lo and Yang, 2017)¹³ reported that in those patients with motor deficit, survival was significantly improved when surgery was performed within 7 days of the development of motor deficit compared to situations when surgery was carried out 7 days after onset. This was the only study that showed that the timing of surgery plays a significant role w.r.t. survival following the onset of spinal cord compression symptoms. Four articles identified that a pre-operative intact motor function and or ambulatory status conferred a higher likelihood of a better post-operative outcome, not just in relation to survival but also in relation to post-operative ambulation as well as a greater tendency towards suitability for adjuvant treatment. Even for the same scoring system e.g. tokuhashi and its effectiveness in predicting survival, results from different studies varied in their outcome. The Karnofsky Performance Status (KPS) being the most commonly used tool to assess functional impairment, the Eastern Cooperative Oncology Group (ECOG) performance status being used in two studies. 23 studies identified an improvement in neurological function following surgery. The most common functional scale used to assess neurological outcome was the Frankel scale, 3 studies used the American Spinal Injury Association (ASIA) impairment scale for this purpose. Wound problems including infection and dehiscence appeared to be the most commonly reported surgical complication. (25 studies). The most commonly used surgical technique involved a posterior approach with decompression, with or without stabilisation. Less commonly employed techniques included percutaneous pedicle screw fixation associated with or without mini-decompression as well as anterior approaches involving corpectomy and instrumentation. 9 studies included in their data, the effect of radiation therapy in combination with surgery or as a comparison used as an alternative to surgery in spinal metastases.

CONCLUSIONS

We provide a systematic literature review on the outcomes of decompressive surgery for spinal metastases. We analyse survival data, motor function, neurological function, as well as the techniques of surgery used. Where appropriate complications of surgery are also highlighted. It is the authors' intention to provide the reader with a reference text where this information is ready to hand, allowing for the consideration of means and methods to improve and optimise the standard of care in patients undergoing surgical intervention for metastatic spinal disease.

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.

Neoplastic Myelopathies

PURPOSE OF REVIEW

This article reviews the current classification system of primary spinal cord tumors and explores evolving diagnostic and therapeutic strategies for both primary tumors and metastatic tumors to various compartments of the spinal cord.

RECENT FINDINGS

The 2016 World Health Organization classification system allows for more precise prognostication of and therapy for spinal cord tumors and has identified new entities, such as the diffuse midline glioma, H3 K27M mutant. Whole-exome sequencing reveals that the genetic background of primary glial spinal cord neoplasms differs from that of their intracranial histologic counterparts in ways that can potentially influence therapy. Targeted and immune checkpoint therapies have improved survival for patients with melanoma and lung cancer and have simultaneously produced novel complications by enhancing radiation toxicity in some cases and by facilitating the emergence of novel autoimmune and paraneoplastic syndromes involving the spinal cord, such as neuromyelitis optica spectrum disorder and syndromes associated with anti-Hu and collapsin response mediator protein-5 (CRMP-5) antibodies. These conditions must be distinguished from tumor or infection. Epidural spinal cord compression treatment paradigms have changed with the advent of robotic surgery and advances in radiation therapy.

SUMMARY

Neoplastic myelopathies subsume a wide spectrum of pathologies. Neoplastic cord involvement may be primary or secondary and may be approached diagnostically by the particular spinal cord compartment localization. Primary spinal cord tumors account for only 2% to 4% of primary central nervous system tumors, ranging from low-grade glial neoplasms to malignant tumors. Metastatic malignancy to the epidural or leptomeningeal spaces is more common than primary cord tumors. Differential diagnoses arising in the course of evaluation for cord tumors include myelopathies related to radiation or chemotherapy and paraneoplastic syndromes, all of which are sources of significant morbidity. Knowledge of genetic syndromes and the biologic behavior of diverse histologies together with selective application of surgery, radiation, and targeted therapies can facilitate diagnosis, minimize surgical morbidity, and prolong quality of life.

What Predicts the Prognosis of Spinal Metastases in Separation Surgery Procedures?

BACKGROUND

Separation surgery is performed to provide a safe gap between the epidural tumor and spinal cord for postoperative stereotactic body radiotherapy (SBRT) in cases of spinal metastases. However, there is a gap in evidence regarding sufficient tumor resection in separation surgery. We describe the prognoses according to the extent of resection in separation surgery.

METHODS

This retrospective study included 36 consecutive patients who underwent separation surgery and postoperative SBRT between December 2016 and December 2019 at a single center. Local control (LC), overall survival (OS), distance of separation (DS), and quality-of-life parameters were analyzed. P values <0.05 were considered statistically significant.

RESULTS

Patients were assigned to the aggressive resection group (ARG, n = 18) or moderate resection group (MRG, n = 18), with estimated LC and OS at 1 year of 79.0% and 75.9%, respectively. There were no significant differences between ARG and MRG in estimated LC (85.9% vs. 72.2%; P = 0.317) or OS (69.3% vs. 80.9%, P = 0.953) at 1 year. All 5 patients in MRG who developed local progression had less satisfactory tumor resection with DS <3 mm. A borderline significant difference in estimated LC at 1 year was noted between individuals with DS <3 mm and those with DS ≥3 mm (51.9% vs. 100.0%; P = 0.053) in MRG. There was no statistical difference between ARG and MRG in quality-of-life parameters.

CONCLUSIONS

Moderate resection of ventral dural mass did not significantly reduce patients' prognosis in separation surgery. However, the minimal distance between the postoperative residual epidural tumor and spinal cord should be ≥3 mm.

Separation surgery for metastatic epidural spinal cord compression: A qualitative review

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Separation surgery is a new concept for metastatic spinal cord compression treatment.

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Stereotactic radiosurgery increased local control, overcoming radio-resistance’s idea.

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The surgery goal shifted towards creating targets for radiations avoiding cord damages.

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Minimal invasive strategies could allow quick return to systemic therapies.

Introduction

The new concept of separation surgery has changed the surgical paradigms for the treatment of metastatic epidural spinal cord compression (MESCC), shifting from aggressive cytoreductive surgery towards less invasive surgery with the aim to achieve circumferential separation of the spinal cord and create a safe target for high dose Stereotactic Body Radiation Therapy (SBRT), which turned out to be the real game-changer for disease’s local control.

Discussion

In this review a qualitative analysis of the English literature has been performed according to the rating of evidence, with the aim to underline the increasingly role of the concept of separation surgery in MESCC treatment. A review of the main steps in the evolution of both radiotherapy and surgery fields have been described, highlighting the important results deriving from their integration.

Conclusion

Compared with more aggressive surgical approaches, the concept of separation surgery together with the advancements of radiotherapy and the use of SBRT for the treatment of MESCC showed promising results in order to achieve a valuable local control while reducing surgical related morbidities and complications.