Surgical strategy for spinal metastases

Are spine metastasis survival scoring systems outdated and do they underestimate life expectancy? Caution in surgical recommendation guidance

OBJECTIVE

Survival scoring systems for spine metastasis (SPM) were designed to help surgical practice. The authors sought to validate the prognostic accuracy of the main preoperative scoring systems for SPM.

METHODS

It was hypothesized that true patient survival in SPM was better than that predicted using prognosis scores. To investigate this hypothesis, the authors designed a French national retrospective study of a prospectively collected multicenter database involving 739 patients treated for SPM between 2014 and 2017.

RESULTS

In this series, the median survival time for all patients from an SPM diagnosis was 17.03 ± 1.5 months. Sensitivity and specificity were estimated using the area under the curve (AUC). The AUC of Tomita's prognosis score was the lowest and poorest (0.4 ± 0.023, range 0.35-0.44), whereas the AUC of the Tokuhashi score was the highest (0.825). The Lei score presented an AUC of 0.686 ± 0.022 (range 0.64-0.7), and the Rades score showed a weaker AUC (0.583 ± 0.020, range 0.54-0.63). Differences among AUCs were all statistically significant (p < 0.001). The modified Bauer score and the Rades score had the highest rate of agreement in predicting survival, with a weighted Cohen's kappa of 0.54 and 0.41, respectively, indicating a moderate agreement. The revised Tokuhashi and Lei scores had a fair rate of agreement (weighted Cohen's kappa = 0.24 and 0.22, respectively). The van der Linden and Tomita scores demonstrated the worst performance, with only a "slight" rate of agreement (weighted Cohen's kappa = 0.19 and 0.16, respectively) between what was predicted and the actual survival.

CONCLUSIONS

The use of prognostic scoring systems in the estimation of survival in patients with SPM has become obsolete and therefore underestimates survival. Surgical treatment decisions should no longer be based on survival estimations alone but must also take into account patient symptoms, spinal instability, and quality of life.

Does the Region of the Spine Involved with Metastatic Tumor Affect Outcomes of Surgical Treatments?

OBJECTIVE

Spinal metastases occur primarily in the thoracic spine (50%-60%), less commonly in the lumbar (30%-35%), and, infrequently, in the cervical spine (10%-15%). There has been only 1 study with a limited population comparing the postoperative outcome among cervical, thoracic, and lumbar spine metastasis. The aim of this study is to identify whether the region of surgically treated spinal metastasis affects postoperative outcomes.

METHODS

A retrospective study of patients with spinal metastasis was performed. The collected data were as follows: age, gender, smoking history, tumor histology, revised Tokuhashi score, preoperative and postoperative American Spinal Injury Association score, region of spinal metastasis, ambulatory status, surgical approach, surgery time, blood loss, complications, length of hospital stay, postoperative pain relief, postoperative adjuvant therapy, and survival. Data were analyzed to identify the factors affecting the survival and postoperative functional outcome.

RESULTS

We studied 191 patients with spinal metastasis including 47 cervical spine metastases, 96 thoracic spine metastases, and 48 lumbar spine metastases, with a mean age of 60.91 ± 9.72 years. The overall median survival was 7 months (95% confidence interval, 2.9-20.63 months). Univariate analysis showed that region of the spine involved with metastasis did not significantly affect the survival and postoperative motor function improvement. Multivariate analysis showed that revised Tokuhashi score, postoperative radiotherapy, and postoperative chemotherapy were independent factors affecting survival. The rate of 30-day complications among patients with different regions of spine metastasis did not reach significance.

CONCLUSIONS

The postoperative outcomes of patients undergoing surgery for metastases are not affected by the region of the spine.

Prone transpsoas lumbar corpectomy: simultaneous posterior and lateral lumbar access for difficult clinical scenarios

OBJECTIVE

Lateral lumbar corpectomy with interbody fusion has been well described via a transpsoas approach in the lateral position, as has lumbar interbody fusion with posterior fixation in the prone position. However, no previous report has described the use of both an open posterior approach and a lateral transpsoas approach simultaneously in the prone position. Here, the authors describe their technique of performing transpsoas lumbar corpectomy in the prone position in order to have simultaneous posterior and lateral access for difficult clinical scenarios, and they report their early clinical experience.

METHODS

The surgical technique for simultaneous posterior and lateral transpsoas access to the lumbar spine was reviewed and described in detail. The cases of 2 patients who underwent simultaneous posterior and lateral access in the prone position for complex lumbar pathology were retrospectively reviewed. Clinical presentation, preoperative radiographs, postoperative course, and postoperative radiographs were reviewed.

RESULTS

The first patient presented after previous transforaminal lumbar interbody fusion that was complicated by significant subsidence of the intervertebral cage, vertebral body split fracture, rotational instability, and resulting spinal stenosis. A simultaneous posterior and lateral transpsoas approach in the prone position allowed for removal of the previous cage, lumbar corpectomy, and rigid posterior fixation with direct decompression. The second patient had a significant pathologic burst fracture secondary to a plasmacytoma with retropulsion, resulting in vertebra plana and significant canal stenosis. Simultaneous approaches allowed for complete resection of the plasmacytoma, restoration of lumbar alignment, rigid fixation, and direct posterior decompression. There were no short-term complications, and both patients had resolution of their preoperative symptoms.

CONCLUSIONS

Simultaneous posterior and lateral transpsoas access to the lumbar spine in the prone position is a previously unreported technique that allows a safe surgical approach to difficult clinical scenarios.

Does knowledge of the primary tumour affect survival after surgery for spinal metastatic disease? A retrospective longitudinal cohort study

OBJECTIVES

To compare survival after surgery for patients with spinal metastatic disease with known primary tumour (KPT) versus patients with unknown primary tumour (UPT).

PARTICIPANTS

393 patients 18 years or older (270 men and 123 women, mean age 67.3 years) undergoing surgery at Uppsala University Hospital in Swedenbetween 2006 and 2016due to spinal metastatic disease . 271 patients (69%) had a KPT at the time of surgery and 122 (31%) had an UPT.

INTERVENTIONS

Decompressive and/or stabilising spine surgery due to spinal metastatic disease.

PRIMARY OUTCOME

Survival (median and mean) after surgery.

RESULTS

The estimated median survival time after surgery for patients with KPT was 7.4 months (95% CI 6.0 to 8.7) and mean survival time was 21.6 months (95% CI 17.2 to 26.0). For patients with UPT, the median estimated survival time after surgery was 15.6 months (95% CI 7.5 to 23.7) and the mean survival time was 48.1 months (95% CI 37.3 to 59.0) (Breslow, p=0.001). Unknown primary cancer was a positive predictor of survival after surgery (Cox regression, HR=0.58, 95% CI 0.46 to 0.73).

CONCLUSION

In this study, patients with spinal metastasis and UPT had a longer expected survival after surgery compared with patients with KPT. This suggests that patients with UPT and spinal metastasis should not be withheld from surgery only based on the fact that the primary tumour is unknown.

The emergence of new prognostic scores in lung cancer patients with spinal metastasis: A 12-year single-center retrospective study

Objective: Lung cancer patients exhibit spinal metastases from a specific population, and with this study, we aimed to develop a model that can predict this particular group's survival.

Methods: Data were retrospectively collected from 83 lung cancer patients who underwent spinal metastasis surgery at our center from 2009 to 2021. After the initial assessment of treatment and scoring effects, a nomogram for survival prediction was created by identifying and integrating critical prognostic factors, followed by a consistency index (C-index) to measure consistency, and finally, a subject working characteristic curve (ROC) to compare the predictive accuracy of the three existing models.

Results: The mean postoperative survival was 14.7 months. Surgical treatment significantly improved the VAS and Frankel scores in lung cancer patients with spinal metastases. The revised Tokuhashi score underestimated the life expectancy of these patients. Six independent prognostic factors, including age, extraspinal bone metastasis foci, visceral metastasis, Frankel score, targeted therapy, and radiotherapy, were identified and incorporated into the model. Calibration curves for 3-, 6-, and 12-month overall survival showed a good concordance between predicted and actual risk. The nomogram C-index for the cohort study was 0.800 (95% confidence interval [CI]: 0.757-0.843). Model comparisons showed that the nomogram's prediction accuracy was better than revised Tokuhashi and Bauer's scoring systems.

Conclusions: Spine surgery offered patients the possibility of regaining neurological function. Having identified shortcomings in existing scoring systems, we have recreated and validated a new nomogram that can be used to predict survival outcomes in patients with spinal metastases from lung cancer, thereby assisting spinal surgeons in making surgical decisions and personalizing treatment for these patients.

Prognostic scores for survival as decisional support for surgery in spinal metastases: a performance assessment systematic review

PURPOSE

To review the evidence on the relative prognostic performance of the available prognostic scores for survival in spinal metastatic surgery in order to provide a recommendation for use in clinical practice.

METHODS

A systematic review of comparative external validation studies assessing the performance of prognostic scores for survival in independent cohorts was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. Eligible studies were identified through Medline and Embase until May 2021. Studies were included when they compared at least four survival scoring systems in surgical or mixed cohorts across all primary tumor types. Predictive performance was assessed based on discrimination and calibration for 3-month, 1-year and overall survival, and generalizability was assessed based on the characteristics of the development cohort and external validation cohorts. Risk of bias and concern regarding applicability were assessed based on the 'Prediction model study Risk Of Bias Assessment Tool' (PROBAST).

RESULTS

Twelve studies fulfilled the inclusion criteria and covered 17 scoring systems across 5.130 patients. Several scores suffer from suboptimal development and validation. The SORG Nomogram, developed in a large surgical cohort, showed good discrimination on 3-month and 1-year survival, good calibration and was superior in direct comparison with low risk of bias and low concern regarding applicability. Machine learning algorithms are promising as they perform equally well in direct comparison. Tokuhashi, Tomita and other traditional risk scores showed suboptimal performance.

CONCLUSION

The SORG Nomogram and machine learning algorithms outline superior performance in survival prediction for surgery in spinal metastases. Further improvement by comparative validation in large multicenter, prospective cohorts can still be obtained. Given the heterogeneity of spinal metastases, superior methodology of development and validation is key in improving future machine learning systems.

A Prognostic Index for Predicting Survival of Patients Undergoing Radiation Therapy for Spine Metastasis Using Recursive Partitioning Analysis

Background: Physicians' estimate of life expectancy in patients with spine metastasis frequently impacts treatment decisions regarding surgery, radiation techniques, dose, and fractionation. Objective: We aimed to identify predictors of survival and generate a stratification schema that could guide clinical decision making. Materials and Methods: We identified 269 patients who have undergone surgery and/or radiation for spine metastasis from 2002 to 2013 at an academic medical institution in the United States. A univariate survival analysis was carried out using the Kaplan-Meier method. Differences in survival by histology were assessed using the log-rank test. Multivariate analysis was performed using the Cox proportional hazards model, then using the same variables, recursive partitioning analysis (RPA) was conducted to determine risk groups associated with survival. Results: The median overall survival was 4.76 months. Twenty percent, 40%, and 57% of patients died within one, three, and six months of radiation treatment, respectively. RPA analysis resulted in three classes; class I included patients with Karnofsky Performance Status (KPS) ≥80. Class II included patients with KPS <80 and radioresistant or favorable histologies. Class III included all other histologies. Median survival in months was 11.4, 6.3, and 2.0, respectively. Conclusion: We developed a stratification schema predictive of survival in patients with spine metastasis. This RPA classification should be validated in independent patient populations from several institutions and may ultimately identify patients who are good candidates for more complex treatment regimens, such as stereotactic body radiotherapy.

[Treatment strategies for pathological fractures of the spine]

BACKGROUND

Pathological fractures and instabilities of the spine are most often caused by primary tumors that hematogenously metastasize into the spine. In this context breast, prostate, kidney cell and bronchial carcinomas are the most relevant causative diseases. Furthermore, multiple myeloma is another frequent entity. Primary tumors of the spine are correspondingly rare and only make up a small proportion of all malignant processes in the spine.

DECISION MAKING

The main symptom of pain is prognostically unfavorable in this context and is often associated with progressive instability or pathological fractures. To objectify the treatment approach the neurological status, an oncological assessment, the biomechanical stability and (systemic) general condition (NOMS criteria) of the patient have to be considered. Another major factor is the radiation sensitivity of the tumor. The spinal instability neoplastic (SIN) score is recommended to assess stability. Regardless of whether conservative or surgical treatment is carried out, interdisciplinary cooperation between the specialist departments must be guaranteed in order to achieve adequate treatment for the patient.

TREATMENT

If a curative approach is followed an individualized and interdisciplinary surgical strategy must be performed to achieve an R0 resection, usually as a spondylectomy. In the case of palliative treatment, the goal of surgical treatment must be pain reduction, stability and avoidance or restoration of neurological deficits. This requires stabilization in a percutaneous or open technique, possibly in combination with decompression and local tumor debulking.

Predictive factors of the 30-day mortality after surgery for spinal metastasis: Analysis of a nationwide database

BACKGROUND

Surgical procedure for symptomatic spinal metastasis is expected to improve the quality of life. Factors related to short-term perioperative mortality after surgery for spinal metastasis may be different from those related to long-term mortality, which have classically been used to determine the indication for surgery. The purposes of this study were to evaluate factors related to the 30-day mortality after surgery for spinal metastasis and create an integer risk scoring system.

METHODS

Using the Diagnosis Procedure Combination database from 2010 to 2016, we extracted data of patients who underwent surgical procedure for spinal metastasis. Multivariable logistic regression analysis was performed to clarify the association between patient backgrounds and the 30-day postoperative mortality. We created a risk scoring system using regression coefficients to estimate the 30-day mortality for each patient.

RESULTS

Among 3524 patients, the 30-day mortality was 2.6%. Factors associated with a higher 30-day mortality were male sex (odds ratio, 2.50 [95% confidence interval, 1.45-4.31]), emergency admission (1.80 [1.11-2.92]), rapid growth tumors (3.83 [2.49-5.90]), and non-skeletal metastasis (2.27 [1.42-3.64]). In patients with the maximum risk score of five, the 30-day mortality was 16.2%.

CONCLUSIONS

Factors related to the 30-day mortality were male sex, emergency admission, rapid growth tumors, and non-skeletal metastasis. These findings provide spine surgeons and patients knowledge of the potential risk of short-term perioperative mortality and allow them to consider the risk of surgery.

The Early Results of Vertebral Pathological Compression Fracture of Extra- nodal Lymphoma with HIV-positive Patients Treated by Percutaneous Kyphoplasty

BACKGROUND

Vertebral pathological compression fracture involving extra-nodal lymphoma impacts negatively on the quality of life of HIV-positive patients. The choice of a safe and effective approach to palliative care in this condition remains a challenge.

OBJECTIVE

The purpose of this study was to investigate the safety and efficacy of percutaneous kyphoplasty (PKP) in the treatment of vertebral pathological compression fracture of extra-nodal lymphoma in HIV-positive patients.

METHODS

A retrospective analysis, from January 2016 to August 2019, was performed on 7 HIVpositive patients, 3 males and 4 females, with extra-nodal lymphoma with a vertebral pathological compression fracture. The patients were treated using percutaneous kyphoplasty in our hospital. Preoperative assessment of the patients was conducted regarding their hematological profile, biochemical indicators, liver and kidney function, blood coagulation function, CD4+T lymphocyte count and viral load. Subsequently, the patients were placed on highly active antiretroviral therapy (HAART) and rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (RCHOP) regimen. Besides, antibiotics, nutritional support and immune-modulating drugs were also administered, rationally. Postoperatively, the height of the anterior edge of the injured vertebrae, Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) values were evaluated. Patients were also monitored for any complications related to the operation.

RESULTS

The average CD4+T cell count for the patients was 164 (range 114 ~247 / ul), while the viral load was 26,269 (range 5,765 ~82,321 copies/ul). All patients received nutritional and immune support and registered significant improvements in the levels of ALB and Hb (P<0.05). In all cases, the operation was uneventful with neither cement leakage nor toxic reactions observed. Similarly, no opportunistic infections, other complications or deaths were reported. The height of the anterior vertebral body and the ODI score of the injured vertebrae were significantly improved immediately after surgery (P<0.05). Compared to the preoperative VAS (7.71±1.11), postoperative values were significantly reduced immediately after surgery (3.85±0.90) and at 2 weeks, 1 month and 6 months post-surgery: 2.71±0.76, 3.29±1.11, and 4.00±0.82, respectively (P<0.01).

CONCLUSION

Supported with appropriate perioperative treatment measures, PKP is safe and effective in the treatment of pathological vertebral compression fracture due to extra-nodal lymphoma in HIV-positive patients.

Cement-Augmented and Dual-Headed Posterior Screw Reconstruction After Corpectomy for Metastatic Tumor Resection

BACKGROUND

Metastatic spinal tumors have a well-documented deleterious effect on the overall strength of the bony spine. Surgical interventions must address not only removal of the tumor itself, but the integrity of reconstructive hardware constructs as well.

METHODS

We present a series of 8 patients with metastatic spine tumors who were successfully treated with tumor resection and reconstruction of residual 3-column defect with cement-augmented fenestrated pedicle screws and dual-rod posterior stabilization.

RESULTS

All patients demonstrated resolution of their presenting neurologic symptoms.

CONCLUSIONS

This series supports the use of the aforementioned constructs in conjunction to provide added stability and reduce hardware failure when treating a diversity of spinal tumors.

Nomogram for Predicting the Postoperative Venous Thromboembolism in Spinal Metastasis Tumor: A Multicenter Retrospective Study

Introduction

Venous thromboembolism can be divided into deep vein thrombosis and pulmonary embolism. These diseases are a major factor affecting the clinical prognosis of patients and can lead to the death of these patients. Unfortunately, the literature on the risk factors of venous thromboembolism after surgery for spine metastatic bone lesions are rare, and no predictive model has been established.

Methods

We retrospectively analyzed 411 cancer patients who underwent metastatic spinal tumor surgery at our institution between 2009 and 2019. The outcome variable of the current study is venous thromboembolism that occurred within 90 days of surgery. In order to identify the risk factors for venous thromboembolism, a univariate logistic regression analysis was performed first, and then variables significant at the P value less than 0.2 were included in a multivariate logistic regression analysis. Finally, a nomogram model was established using the independent risk factors.

Results

In the multivariate logistic regression model, four independent risk factors for venous thromboembolism were further screened out, including preoperative Frankel score (OR=2.68, 95% CI 1.78-4.04, P=0.001), blood transfusion (OR=3.11, 95% CI 1.61-6.02, P=0.041), Charlson comorbidity index (OR=2.01, 95% CI 1.27-3.17, P=0.013; OR=2.29, 95% CI 1.25-4.20, P=0.017), and operative time (OR=1.36, 95% CI 1.14-1.63, P=0.001). On the basis of the four independent influencing factors screened out by multivariate logistic regression model, a nomogram prediction model was established. Both training sample and validation sample showed that the predicted probability of the nomogram had a strong correlation with the actual situation.

Conclusion

The prediction model for postoperative VTE developed by our team provides clinicians with a simple method that can be used to calculate the VTE risk of patients at the bedside, and can help clinicians make evidence-based judgments on when to use intervention measures. In clinical practice, the simplicity of this predictive model has great practical value.

Video-Assisted Thoracoscopic En Bloc Vertebrectomy for Spine Tumors: Technique and Outcomes in a Series of 33 Patients

BACKGROUND

In en bloc vertebrectomy, the posterior approach is associated with limited access to anterior structures (vertebral body, esophagus, aorta, azygos vein). Video-assisted thoracoscopic surgery (VATS) might prove to be advantageous during thoracic en bloc vertebrectomy by allowing a combined anterior-posterior access in the prone position. We describe the technique and review the outcomes of 33 cases of video-assisted thoracoscopic en bloc vertebrectomy.

METHODS

A retrospective, single-center cohort study included all cases of VATS with a minimum follow-up of 1 year. A team of thoracic and orthopaedic surgeons performed the surgical procedure with the patient in a single, prone position. Anterior release was carried out thoracoscopically, followed by posterior en bloc tumor removal.

RESULTS

From 2003 to 2019, 33 patients were included. Nine patients underwent total vertebrectomy (8 had single-level and 1 had 3-level), and 24 patients underwent partial vertebrectomy (1 had single-level, 8 had 2-level, 13 had 3-level, and 2 had 4-level). Ten patients had pulmonary resection. Histology revealed 18 cases (55%) of primary bone tumors, 6 cases (18%) of lung cancer invading the spine, 6 cases (18%) of solitary metastasis, and 3 other cases (9%). The margins were tumor-free in 28 cases (85%). The median operative time was 240 minutes (range, 150 to 510 minutes), with a median blood loss of 1,200 mL (range, 400 to 6,700 mL), and there were 2 cases of conversion to thoracotomy. A total of 33 complications occurred in 18 patients (55%), and these were predominantly pulmonary. One death was surgery-related (infection). One patient had a persistent monoplegia. At a median follow-up of 63 months (range, 12 to 156 months), there were 21 surviving patients (64%) with 2 local recurrences and 1 distant recurrence, and 2 patients (6%) were lost to follow-up. The survival rates were 94% at 1 year, 71% at 2 years, and 68% at 5 years.

CONCLUSIONS

VATS en bloc vertebrectomy may be indicated for T2-to-T11 spine tumors with the exception of massive tumors, substantial chest wall and/or mediastinal invasion, and lung cancer exceeding 7 cm. The technique yielded satisfactory surgical and oncologic outcomes.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Surgical Stabilization for Patients with Mechanical Back Pain Secondary to Metastatic Spinal Disease is Associated with Improved Objective Mobility Metrics: Preliminary Analysis in a Cohort of 26 Patients

OBJECTIVES

To investigate the effect of surgical stabilization for patients with metastatic spinal disease on objective mobility metrics.

METHODS

A retrospective chart review identified patients who had mechanical back pain from metastatic spinal disease and underwent spinal stabilization during 2017. Mobility metrics, the Activity Measure for Post-Acute Care (AM-PAC) inpatient mobility short form (IMSF) and the Johns Hopkins Highest Level of Mobility (JH-HLM), were reviewed.

RESULTS

A total of 26 patients were included in the analysis with median hospital stay of 8 days. Preoperative JH-HLM scores were available for 17 patients with a mean score of 5.4, increasing to mean score of 6.6 at last follow-up (P = 0.036). Preoperative AM-PAC IMSF scores were available for 14 patients with a mean score of 19.4, decreasing slightly to a mean score of 18.7 at last follow-up (P = 0.367). Last follow-up with mobility metrics occurred a median of 6.5 days postoperatively (range: 3-66 days). Multivariable analysis showed that American Spinal Injury Association and Karnofsky Performance Status scores were significantly associated with both JH-HLM and AM-PAC mobility scores at last follow-up. A higher JH-HLM or AM-PAC score was significantly associated with direct home discharge and a higher AM-PAC score was associated with shorter hospital stay.

CONCLUSIONS

Surgical stabilization for patients with mechanical back pain secondary to metastatic spinal disease might lead to an objective improvement in JH-HLM score. JH-HLM and AM-PAC scores may be correlated with length of hospital stay and discharge disposition. Future studies are encouraged to further characterize the role of these mobility metrics in the management plan of these patients.

Surgical Metastasectomy in the Spine: A Review Article

BACKGROUND

The use of surgical metastasectomy (SM) has increased across cancer types in recent decades despite the increasing efficacy of modern systemic treatment modalities. Symptomatic spinal metastases severely compromise patients' performance status. However, as spinal SM is a complex surgery with potentially significant complications, it is not considered the treatment of choice.

METHODS

We reviewed the articles on SM in several primary cancers with different types of metastatic lesions and extracted the data from relevant articles to provide a comprehensive review including the surgical techniques, indications, reported outcomes, and future prospects of SM in spinal metastases.

RESULTS

Total en bloc spondylectomy (TES) is a method of spinal SM associated with a lower risk of tumor recurrence and complications. Intralesional transpedicular osteotomy using a fine threadwire saw allows prevention of spinal cord and nerve root injuries. Spinal SM is considered suitable for patients with controlled primary disease having no evidence of disseminated extraspinal metastases, a completely resectable solitary lesion in the spine, and adequate cardiopulmonary reserve to tolerate the surgery. Metastatic lesions from kidney and thyroid cancers have been reported as the best candidates for spinal SM. Although data about spinal SM are limited, the reported outcomes are favorable with acceptable local recurrence rates in long-term follow-up.

CONCLUSION

In patients with isolated resectable spinal metastases, complete SM including TES is a useful option as it can improve function and survival. However, appropriate patient selection and surgical feasibility remain the most important aspects of management.

IMPLICATIONS FOR PRACTICE

Surgical metastasectomy for spinal metastases may be a potentially curative treatment option with a low risk of local recurrence and lead to prolonged long-term survival if appropriate patients are selected and if the surgery is carried out by experienced surgeons in high-volume centers.

A novel approach to evaluate the effects of artificial bone focal lesion on the three-dimensional strain distributions within the vertebral body

The spine is the first site for incidence of bone metastasis. Thus, the vertebrae have a high potential risk of being weakened by metastatic tissues. The evaluation of strength of the bone affected by the presence of metastases is fundamental to assess the fracture risk. This work proposes a robust method to evaluate the variations of strain distributions due to artificial lesions within the vertebral body, based on in situ mechanical testing and digital volume correlation. Five porcine vertebrae were tested in compression up to 6500N inside a micro computed tomography scanner. For each specimen, images were acquired before and after the application of the load, before and after the introduction of the artificial lesions. Principal strains were computed within the bone by means of digital volume correlation (DVC). All intact specimens showed a consistent strain distribution, with peak minimum principal strain in the range -1.8% to -0.7% in the middle of the vertebra, demonstrating the robustness of the method. Similar distributions of strains were found for the intact vertebrae in the different regions. The artificial lesion generally doubled the strain in the middle portion of the specimen, probably due to stress concentrations close to the defect. In conclusion, a robust method to evaluate the redistribution of the strain due to artificial lesions within the vertebral body was developed and will be used in the future to improve current clinical assessment of fracture risk in metastatic spines.

Spine Metastasis in Elderly: Encouraging Results for Better Survival

MINI

The incidence of spinal metastasis (SpM) is increasing, and life expectancy for patients with malignancy is also rising. The "elderly" represent a population with steady growth in SpM proportion. Bracing is associated with lower survival. We believe that surgery should be considered, regardless of the patient's age.

Evaluation of open and minimally invasive spinal surgery for the treatment of thoracolumbar metastatic epidural spinal cord compression: a systematic review

BACKGROUND

Metastatic epidural spinal cord compression (MESCC) is a debilitating sequela of cancer that results in pain, disability, and neurologic deficits. Surgical techniques have included open surgical (OS) techniques with anterior and/or posterior decompression and fusion procedures. Further technical evolution has led to minimally invasive spinal (MIS) decompression and fusion. The objective of this study is to compare MIS to OS techniques in the treatment of thoracolumbar MESCC.

METHODS

A review of the literature was performed using PubMed database. Inclusion criteria included patients 18 years or older, thoracolumbar MESCC, and surgeries with instrumented fusion. A total of 451 articles met the inclusion criteria and further analysis narrowed them down to 81 articles. Variables collected included blood loss, length of stay, operative time, pre- and postoperative Frankel grade, and complications.

RESULTS

A total of 5726 papers were collected, with a total of 81 papers meeting final inclusion criteria: 26 papers with MIS technique and 55 with OS. A total of 2267 patients were evaluated. They were split into three surgical subtypes of MIS and OS: posterior decompression and fusion, partial corpectomy, and complete corpectomy. Overall, MIS had lower operative time, blood loss, and complications compared to OS. A timeline analysis showed reduction of complication rates in MIS surgery between papers published over a 28-year period.

CONCLUSION

MESCC carries significant morbidity and mortality. Surgical approaches for palliative treatment should account for this fact. We conclude that MIS techniques offer a viable alternative to traditional OS approaches with lower overall morbidity and complications.

Synchronous bone metastasis in lung cancer: retrospective study of a single center of 15,716 patients from Tianjin, China

Background

This study aimed to describe the incidence, clinical characteristics, and prognosis of lung cancer patients with synchronous bone metastasis (SBM) and to analyze the prognostic factors of the lung cancer patients with SBM.

Methods

A total of 15,716 lung cancer patients who were diagnosed between 2009 to 2018 in the Tianjin Medical University Cancer Institute and Hospital were retrospectively reviewed. Among them, patients with SBM were checked. Both the demographic and clinical characteristics were included as follows: age, gender, marital status, history of smoking, alcohol consumption, family history of tumor, Karnofsky score, lymph node metastasis, histological type. Besides, laboratory data such as alkaline phosphatase, lactate dehydrogenase, carcinoembryonic antigen, squamous cell carcinoma antigen, cytokeratin-19 fragment, and neuron specific enolase were also included. The log-rank test and multivariate Cox regression analysis were employed to reveal the potential prognostic predictors. A further analysis using the Kaplan–Meier was employed to demonstrate the difference on the prognosis of LC patients between adenocarcinoma and non-adenocarcinoma.

Results

Among the included patients, 2738 patients (17.42%) were diagnosed with SBM. A total of 938 patients (34.3%) with SBM were successfully followed and the median survival was 11.53 months (95%CI: 10.57–12.49 months), and the 1-, 2-, and 5-year overall survival rate was 51, 17, and 8%, respectively. Multivariable Cox regression results showed history of smoking and high level of NSE were associated with the poor prognosis, while adenocarcinoma histological type was associated with better survival.

Conclusion

The prevalence of SBM in lung cancer is relatively high with poor survival. The lung cancer patients with SBM showed diverse prognosis. Among all the pathological types, the division of adenocarcinoma suggested different prognosis of the lung cancer patients with SBM. The present study emphasized the importance of pathological diagnosis on prognostic determinants in lung cancer patients with SBM.

Radiotherapy and Surgical Advances in the Treatment of Metastatic Spine Tumors: A Narrative Review

Spine tumors encompass a wide range of diseases with a commensurately broad spectrum of available treatments, ranging from radiation for spinal metastases to highly invasive en bloc resection for primary vertebral column malignancies. This high variability in treatment approaches stems both from variability in the goals of surgery (e.g., oncologic cure vs. symptom palliation) and from the significant advancements in surgical technologies that have been made over the past 2 decades. Among these advancements are improvements in surgical technique, namely minimally invasive approaches, increased availability of focused radiation modalities (e.g., proton therapy and linear accelerator devices), and new surgical technologies, such as carbon fiber-reinforced polyether ether ketone rods. In addition, several groups have described nonsurgical interventions, such as vertebroplasty and kyphoplasty for spinal instability secondary to pathologic fracture, and lesion ablation with spinal laser interstitial thermoablation, radiofrequency ablation, or cryoablation. We provide an overview of the latest technological advancements in spinal oncology and their potential usefulness for modern spinal oncologists.

Effects of Surgical Intervention for Bone Metastases on Survival in Patients with Advanced Cancer: A Nationwide Population-Based Cohort Study

Purpose

With recent advances in surgical techniques and instruments, orthopedic surgeons are better equipped to treat metastatic bone disease. There has also been considerable progress in the non-surgical treatment of cancers, specifically in improving the survival rate of patients with advanced cancer. However, it remains unclear whether surgical resection of a metastatic bone lesion poses additional risk to the survival of patients with advanced cancer.

Patients and Methods

This study utilized data from the National Health Insurance Research Database (NHIRD) in Taiwan between 2000 and 2015. Patients aged ≥18 years, who had been recently diagnosed with bone metastases (BM), were enrolled and assigned to either the surgery or non-surgery groups. The demographic characteristics were analyzed, and the adjusted hazard ratios (aHR) of mortality were calculated using Cox regression analysis.

Results

Of the 4,549,226 individuals in the inpatient database of the NHIRD, 83,536 patients with BM were enrolled in this study. Among them, 8802 underwent surgical resection for skeletal metastatic lesion and 66,098 did not. Altogether, 28,691 patients died, including 2798 (31.8%) in the surgery group and 25,893 (39.2%) in the non-surgery group. The aHR for mortality was 0.7-fold lower in the surgery group (p < 0.001).

Conclusion

This study demonstrates that surgical resection of metastatic bone lesions did not pose any additional risk to survival outcomes. Thus, we believe that surgery, if indicated, could have a competitive role in the management of metastatic bone disease.

Posterior vertebral column resection as a safe procedure leading to solid bone fusion in metastatic epidural spinal cord compression

OBJECTIVE

Cancer is one of the leading causes of death and greatly decreases a patient's quality of life. Vertebral metastases often lead to epidural spinal cord compression (ESCC) requiring surgical therapy. It has previously been shown that in patients with metastatic ESCC (MESCC), a surgical intervention leads to an improved outcome. Although the treatment paradigms in spinal metastases have changed and separation surgery followed by stereotactic radiosurgery is considered the best strategy, there are still cases in which 360° decompression with stabilization is indicated. In these patients, a proper bone fusion should be the treatment goal to guarantee good clinical results in extended survival times through progressions in oncological therapies. The aim of this study was to examine the safety and feasibility of posterior vertebral column resection (pVCR) in everyday clinical practice, achievement of bone fusion, and midterm outcome in patients with MESCC.

METHODS

All patients treated with pVCR due to MESCC between 2013 and 2020 were enrolled in this observational single-center study. Demographics, outcome parameters, numeric rating scale (NRS) score, Frankel grade, and Karnofsky Performance Scale (KPS) score were evaluated. Radiological images routinely acquired during follow-up were reviewed and screened for the presence of bone fusion.

RESULTS

Sixty-six patients were treated by eight surgeons. The mean follow-up period was 549 ± 739 days. At baseline, the average age was 64.4 ± 10.9 years. Reported NRS scores (preoperative 6.2 ± 1.7 vs postoperative 3.4 ± 1.6) and segmental kyphosis as measured on sagittal CT images (preoperative 13.5° ± 8.6° vs postoperative 3.8° ± 5.4°) decreased significantly (p < 0.001). In only 2 patients (3%), the Frankel grade worsened postoperatively, whereas in 12 patients (18.2%) an improvement was documented. The KPS score remained constant during the observation period (preoperative 73.2% ± 18.2% vs 78.3% ± 18% at last follow-up). Bone fusion was observed in 26 patients (86.7%) receiving CT more than 100 days after the index surgery.

CONCLUSIONS

pVCR is a reliable surgical technique in daily clinical practice, which proves to be beneficial in terms of short- as well as midterm outcome, as judged by the KPS and NRS. The overall improvement in the Frankel grade shows patient safety. A bone fusion was observed regularly in oncological patients undergoing pVCR. The authors therefore conclude that pVCR is a safe, fast, and efficient strategy to achieve stability and pain relief by achievement of bone fusion in cancer patients.

Intraoperative blood loss in oncological spine surgery

OBJECTIVE

Intraoperative blood loss in patients undergoing oncological spine surgery poses a major challenge for vulnerable patients. The goal of this study was to assess how the surgical procedure, tumor type, and tumor anatomy, as well as anesthesiological parameters, affect intraoperative blood loss in oncological spine surgery and to use this information to generate a short preoperative checklist for spine surgeons and anesthesiologists to identify patients at risk for increased intraoperative blood loss.

METHODS

The authors performed a retrospective analysis of 430 oncological patients who underwent spine surgery between 2013 and 2018 at the university medical spine center. Enrolled patients had metastatic tumor of the spine requiring surgical decompression of neural structures and/or stabilization including tumor biopsy using an open, percutaneous, and/or combined dorsoventral approach. Patients requiring vertebro- and kyphoplasty or biopsy only were excluded. Statistical analyses performed included a multiple linear regression analysis.

RESULTS

The mean intraoperative blood loss in the study patient cohort was 1176 ± 1209 ml. In total, 33.8% of patients received intraoperative red blood cell transfusions. The statistical analyses showed that tumor histology indicating myeloma, operative procedure length, epidural spinal cord compression (ESCC) score, tumor localization, BMI, and surgical strategy were significantly associated with increased intraoperative blood loss or risk of needing allogeneic blood transfusions. Anesthesiological parameters such as the American Society of Anesthesiologists (ASA) Physical Status classification score were not associated with blood loss. Multiple linear regression analysis demonstrated good predictive value (r = 0.437) for a five-item preoperative checklist to identify patients at risk for high intraoperative blood loss.

CONCLUSIONS

The analyses performed in this study demonstrated key factors affecting intraoperative blood loss and showed that a simple preoperative checklist including these factors can be used to identify patients undergoing surgery for metastatic spine tumors who are at risk for increased intraoperative blood loss.

ABBREVIATIONS

ABT = allogeneic blood transfusion; ASA = American Society of Anesthesiologists; ESCC = epidural spinal cord compression; KW = Kruskal-Wallis; MET = metabolic equivalent of task; RBC = red blood cell.

Epidemiology and detection of cement leakage in patients with spine metastases treated with percutaneous vertebroplasty: A 10-year observational study

•

Cement leak is common for percutaneous vertebroplasty in metastatic spinal disease.

•

A proposed and validated algorithm can screen patients with high cement leak risk.

•

The algorithm included four significant characteristics.

•

The validation group AUROC was 0.69, and the goodness-of-fit test P-value was 0.50.

Objectives

To investigate the epidemiology of cement leaks and further develop an algorithm to detect the high risk of cement leaks among advanced cancer patients with metastatic spinal disease treated with percutaneous vertebroplasty.

Methods

This study retrospectively analyzed 309 patients with metastatic spinal disease treated with percutaneous vertebroplasty. Patients were randomly divided into a training group and a validation group. In the training group, 13 potential characteristics were analyzed for their abilities to predict cement leaks. Discal cement leakage and paravertebral cement leakage were excluded from the analysis. Those characteristics identified as having significant predictive value were used to develop a predictive algorithm. Internal validation of the algorithm was performed based on discrimination and calibration qualities.

Results

Overall, cement leaks occurred in 61.17% (189/309) patients. Among the 13 characteristics analyzed, younger age (P = 0.03), extravertebral bone metastases (P = 0.02), increased number of treated vertebrae levels (P < 0.01), and cortical osteolytic destruction in the posterior wall (P = 0.01) were included in the algorithm. This algorithm generates a score between 0 and 16 points, with higher scores indicating a higher risk of cement leakage. The area under the receiver operating characteristic curve (AUROC) value for the algorithm was 0.75 in the training group and 0.69 in the validation group. The mean correct classification rates for the training and validation groups were 73.5% and 64.9%, respectively, and the corresponding P-values of the goodness-of-fit test were 0.70 and 0.50.

Conclusions

Cement leaks are common in patients with metastatic spinal disease treated with percutaneous vertebroplasty. The present study proposed and internally validated an algorithm that can be used to screen patients at high risk of cement leakage.

Utility of prediction model score: a proposed tool to standardize the performance and generalizability of clinical predictive models based on systematic review

OBJECTIVE

The objective of this study was to evaluate the characteristics and performance of current prediction models in the fields of spine metastasis and degenerative spine disease to create a scoring system that allows direct comparison of the prediction models.

METHODS

A systematic search of PubMed and Embase was performed to identify relevant studies that included either the proposal of a prediction model or an external validation of a previously proposed prediction model with 1-year outcomes. Characteristics of the original study and discriminative performance of external validations were then assigned points based on thresholds from the overall cohort.

RESULTS

Nine prediction models were included in the spine metastasis category, while 6 prediction models were included in the degenerative spine category. After assigning the proposed utility of prediction model score to the spine metastasis prediction models, only 1 reached the grade of excellent, while 2 were graded as good, 3 as fair, and 3 as poor. Of the 6 included degenerative spine models, 1 reached the excellent grade, while 3 studies were graded as good, 1 as fair, and 1 as poor.

CONCLUSIONS

As interest in utilizing predictive analytics in spine surgery increases, there is a concomitant increase in the number of published prediction models that differ in methodology and performance. Prior to applying these models to patient care, these models must be evaluated. To begin addressing this issue, the authors proposed a grading system that compares these models based on various metrics related to their original design as well as internal and external validation. Ultimately, this may hopefully aid clinicians in determining the relative validity and usability of a given model.

Surgical management of spinal metastases involving the cervicothoracic junction: results of a multicenter, European observational study

OBJECTIVE

Surgical management of spinal metastases at the cervicothoracic junction (CTJ) is highly complex and relies on case-based decision-making. The aim of this multicentric study was to describe surgical procedures for metastases at the CTJ and provide guidance for clinical and surgical management.

METHODS

Patients eligible for this study were those with metastases at the CTJ (C7-T2) who had been consecutively treated in 2005-2019 at 7 academic institutions across Europe. The Spine Instability Neoplastic Score, neurological function, clinical status, medical history, and surgical data for each patient were retrospectively assessed. Patients were divided into four surgical groups: 1) posterior decompression only, 2) posterior decompression and fusion, 3) anterior corpectomy and fusion, and 4) anterior corpectomy and 360° fusion. Endpoints were complications, surgical revision rate, and survival.

RESULTS

Among the 238 patients eligible for inclusion this study, 37 were included in group 1 (15%), 127 in group 2 (53%), 18 in group 3 (8%), and 56 in group 4 (24%). Mechanical pain was the predominant symptom (79%, 189 patients). Surgical complications occurred in 16% (group 1), 20% (group 2), 11% (group 3), and 18% (group 4). Of these, hardware failure (HwF) occurred in 18% and led to surgical revision in 7 of 8 cases. The overall complication rate was 34%. In-hospital mortality was 5%.

CONCLUSIONS

Posterior fusion and decompression was the most frequently used technique. Care should be taken to choose instrumentation techniques that offer the highest possible biomechanical load-bearing capacity to avoid HwF. Since the overall complication rate is high, the prevention of in-hospital complications seems crucial to reduce in-hospital mortality.

Clinical outcomes and prognostic factors following the surgical resection of renal cell carcinoma spinal metastases

The efficacy of surgical resection in metastatic renal cell carcinoma is an active and important research field in the postcytokine era. Bone metastases, especially in the spine, compromise patient performance status. Metastasectomy is indicated, if feasible, because it helps to achieve the best clinical outcomes possible compared with other treatments. This study examined the postoperative survival and prognostic factors in patients who underwent metastasectomy of spinal lesions. The retrospective study included 65 consecutive patients with metastatic renal cell carcinomas who were operated on by spinal metastasectomy between 1995 and 2017 at our institution. The cancer‐specific survival times from the first spinal metastasectomy to death or the last follow‐up (≥3 years) were determined using Kaplan‐Meier analysis. Potential factors influencing survival were analyzed using Cox proportional hazard models. Planned surgical resection of all the spine tumors was achieved in all patients. Of these, 38 had complete metastasectomy of all visible metastases, including extraspinal lesions. In all patients, the estimated median cancer‐specific survival time was 100 months. The 3‐, 5‐, and 10‐year cancer‐specific survival rates were 77%, 62%, and 48%, respectively. The survival times after spinal metastasectomy were similar in both cytokine and postcytokine groups. In multivariate analyses, postoperative disability, the coexistence of liver metastases, multiple spinal metastases, and incomplete metastasectomy were significant risk factors associated with short‐term survival. Complete metastasectomy, including extraspinal metastases, was associated with improved cancer‐specific survival. Proper patient selection and complete metastasectomy provide a better prognosis in metastatic renal cell carcinoma patients.

Comparison of Minimally Invasive Total versus Subtotal Resection of Spinal Tumors: A Systematic Review and Meta-Analysis

OBJECTIVE

With the advent of minimally invasive techniques, minimally invasive spine surgery (MISS) has become a realistic option for many spine cases. This study aims to evaluate the operative and clinical outcomes of MISS for total versus subtotal tumor resection from current evidence.

METHODS

A literature search was performed using the search term (Minimally invasive surgery OR MIS) AND (spine tumor OR spinal tumor). Studies including both minimally invasive total and subtotal resection cases with operative or clinical data were included.

RESULTS

Seven studies describing 159 spinal tumor cases were included. Compared with total resection, subtotal resection showed no significant differences in surgical time (mean difference (MD), 9.44 minutes; 95% confidence interval [CI], -47.66 to 66.55 minutes; P = 0.37), surgical blood loss (MD, -84.72 mL; 95% CI, -342.82 to 173.39 mL; P = 0.34), length of stay (MD, 1.38 days; 95% CI, -0.95 to 3.71 days; P = 0.17), and complication rate (odds ratio, 9.47; 95% CI, 0.34-263.56; P = 0.12). Pooled analyses with the random-effects model showed that neurologic function improved in 89% of patients undergoing total resection, whereas neurologic function improved in 61% of patients undergoing subtotal resection.

CONCLUSIONS

Our analyses show that there is no significant difference in operative outcomes between total and subtotal resection. Patients undergoing total resection showed slightly better improvement in neurologic outcomes compared with patients undergoing subtotal resection. Overall, this study suggests that both total and subtotal resection may result in comparable outcomes for patients with spinal tumors. However, maximal safe resection remains the ideal treatment because it provides the greatest chance of long-term benefit.

Survival of Spinal Metastasis Disease based on Immunohistochemistry Subtype of Breast Cancer: A Systematic Review and Meta-analysis

BACKGROUND: Breast cancer is categorized as a slow-growth tumor in the spinal metastases disease (SMD) scoring system. Based on immunohistochemistry, breast cancer has four subtypes: Luminal A (LumA), luminal B (LumB), human epidermal growth factor 2 (Her-2) type, and triple-negative breast cancer (TNBC). TNBC has the poorest prognosis. AIM: This study aimed to describe the survival time of breast cancer with SMD based on immunohistochemistry subtypes through systematic review and meta-analysis. METHODS: This is a systematic review and meta-analysis study. This study used electronic articles published in PubMed and CENTRAL online database. We used keywords ([breast] AND [cancer] AND [spine] AND [metastasis]) to find eligible studies. Articles included were full-text studies in English. Survival time as the outcome was pooled according to the immunohistochemistry subtype of breast cancer. Statistical analysis was performed using software Stata. RESULTS: Five articles met our inclusion and exclusion criteria. LumA, LumB, Her-2 type, and TNBC have a survival time of 32.84 months, 35.20 months, 60.8 months, and 14.27 months, respectively. CONCLUSION: TNBC has the lowest survival time in the pooled analysis. We proposed TNBC be categorized as a moderate growth primary tumor.

Comprehensive surgical treatment strategy for spinal metastases

The management of patients with spinal metastases (SM) requires a multidisciplinary team of specialists involved in oncological care. Surgical management has evolved significantly over the recent years, which warrants reevaluation of its role in the oncological treatment concept. Any patient with a SM was screened for study inclusion. We report baseline characteristics, surgical procedures, complication rates, functional status and outcome of a large consecutive cohort undergoing surgical treatment according to an algorithm. 667 patients underwent 989 surgeries with a mean age of 65 years (min/max 20–94) between 2007 and 2018. The primary cancers mostly originated from the prostate (21.7%), breast (15.9%) and lung (10.0%). Surgical treatment consisted of dorsoventral stabilization in 69.5%, decompression without instrumentation in 12.5% and kyphoplasty in 18.0%. Overall survival reached 18.4 months (95% CI 9.8–26.9) and the median KPS increased by 10 within hospital stay. Surgical management of SMs should generally represent the first step of a conclusive treatment algorithm. The need to preserve long-term symptom control and biomechanical stability requires a surgical strategy currently not supported by level I evidence.

The "Spinal Metastasis Invasiveness Index": A Novel Scoring System to Assess Surgical Invasiveness

STUDY DESIGN

Retrospective review.

OBJECTIVE

The aim of this study was to develop a surgical invasiveness index for metastatic spine tumor surgery (MSTS) that can serve as a standardized tool in predicting intraoperative blood loss and surgical duration; for the purpose of ascertaining resource requirements and aiding in patient education.

SUMMARY OF BACKGROUND DATA

Magnitude of surgery is important in the metastatic spine disease (MSD) population since these patients have a continuing postoperative oncological process; a consideration that must be taken into account to maintain or improve quality of life. Surgical invasiveness indices have been established for general spine surgery, adult deformity, and cervical deformity, but not yet for spinal metastasis.

METHODS

Demographic, oncological, and procedural data were collected from consecutive patients that underwent MSTS. Binary logistic regression, using median values for surgical duration and intraoperative estimated blood loss (EBL), was used to determine statistical significance of variables to be included in the "spinal metastasis invasiveness index" (SMII). The corresponding weightage of each of these variables was agreed upon by experienced spine surgeons. Multivariable regression analysis was used to predict operative time and EBL while controlling for demographical, procedural, and oncological characteristics.

RESULTS

Two hundred and sixty-one MSD patients were included with a mean age of 59.7-years and near equal sex distribution. The SMII strongly predicted extended surgical duration (R2 = 0.28, P < 0.001) and high intraoperative blood loss (R2 = 0.18, P < 0.001). When compared to a previously established surgical invasiveness index, the SMII accounted for more variability in the outcomes. For every unit increase in score, there was a 42-mL increase in mean blood loss (P < 0.001) and 5-minute increase in mean operative time (P < 0.001).

CONCLUSION

Long surgical duration and high blood loss were strongly predicted by the newly developed SMII. The use of the SMII may aid in preoperative risk assessment with the goal of improving patient outcomes and quality of life.Level of Evidence: 4.

Surgical Intervention for Patients With Spinal Metastasis From Lung Cancer: A Retrospective Study of 87 Cases

STUDY DESIGN

This was a retrospective study.

OBJECTIVE

Evaluate the prognosis and surgical outcomes of patients with spinal metastasis from lung cancer undergoing surgical treatment.

SUMMARY OF BACKGROUND DATA

The spine is the most common site of metastatic lesions in patients with lung cancer. There have been a few studies, all small cohorts studying prognosis and surgical outcomes and the results were discordant.

MATERIALS AND METHODS

A retrospective study on a prospectively collected database was conducted. Data collected were the following: age, tobacco use, tumor histology, American Spinal Injury Association score, revised Tokuhashi score, ambulatory status, perioperative complications, postoperative adjuvant treatment, and survival time. Univariate and multivariate analyses were performed to identify the prognostic factors of survival.

RESULTS

The authors studied 87 patients with a mean age of 61.3±1.9 years. Median survival was 4.1±0.8 months. Twenty-eight patients (32.2%) lived >6 months and 14 patients (16.1%) lived >12 months. The medical complication rate was 13.8% and the surgical complication rate was 5.7%. The 30-day mortality rate was 4.6%. Univariate analysis showed tobacco use, revised Tokuhashi score, preoperative and postoperative American Spinal Injury Association score, postoperative walking ability, postoperative radiotherapy, and postoperative chemotherapy were prognostic factors. There was no significant difference in survival between adenoma lung cancers, nonadenoma lung cancers, and small cell lung cancers (P=0.51). Multivariate analysis revealed tobacco use, revised Tokuhashi score, postoperative walking ability, postoperative radiotherapy, and postoperative chemotherapy affected the survival.

CONCLUSIONS

This is the largest reported study of patients with spinal metastasis from lung cancer undergoing spinal surgery. It is the first study showing that tobacco use has a negative impact on survival. Spinal surgery improves the quality of life and offers nonambulatory patients a high chance of regaining walking ability with an acceptable risk of complications.

Percutaneous bipolar radiofrequency ablation for spine metastatic lesions

PURPOSE

The purpose of this review is to become familiar with the most common indications for imaging guided percutaneous bipolar radiofrequency ablation, to learn about different technical considerations during performance providing the current evidence. Controversies concerning products will be addressed.

METHODS

We performed a literature review excluding non-English studies and case reports. All references of the obtained articles were also evaluated for any additional information.

RESULTS

RFA achieves cytotoxicity by raising target area temperatures above 60 °C, and may be used to achieve total necrosis of lesions smaller than 3 cm in diameter, to debulk and reduce the pain associated with larger lesions, to prevent pathological fractures due to progressive osteolysis or for cavity creation aiming for targeted cement delivery in case of posterior vertebral wall breaching. Protective ancillary techniques should be used in order to increase safety and augment efficacy of RFA in the spine.

CONCLUSION

Percutaneous radiofrequency ablation of vertebral lesions is a reproducible, successful and safe procedure. Ablation should be combined with vertebral augmentation in all cases. In order to optimize maximum efficacy a patient- and a lesion-tailored approach should both be offered focusing upon clinical and performance status along with life expectancy of the patient as well as upon lesion characteristics.

Overall survival nomogram for patients with spinal bone metastases (SBM)

•Demographic features are essential for a more personalize survival prediction of spinal bone metastasis (SBM).•Women have a relatively better survival chance than men before 75 years, while men have better survival after this age.•SBM survival is not dependent on the number of spinal metastases.

[Case report of an osseous (and lymphogenic) thymic carcinoma in an adult]

A Thymic carcinoma in adults is rare. We present the case of a 47-year-old man, who was treated conservatively for spondylolisthesis L5/S1 in our institution for several years. In the further course, the patient complained about pain exacerbation with acute lower back pain. Cross-sectional scanning showed a tumor of the lumbar vertebral body three. A biopsy of this mass revealed a metastatic thymic carcinoma of the squamous cells. After palliative therapy, the patient died 9 months after initial diagnosis.

A Novel Nomogram for Survival Prediction of Patients with Spinal Metastasis From Prostate Cancer

STUDY DESIGN

A retrospective study of 84 patients with spinal metastasis from prostate cancer (SMPCa) was performed.

OBJECTIVE

The aim of this study was to predict the survival of patients with SMPCa by establishing an effective prognostic nomogram model, associating with the affecting factors and compare its efficacy with the existing scoring models.

SUMMARY OF BACKGROUND DATA

Prostate cancer (PCa) is the second most frequently malignant cancer causing death in men, and the spine is the most common site of bone metastatic burden. The aim of this study was to establish a prognostic nomogram for survival prediction of patients with SMPCa, explore associated factors, and compare the effectiveness of the new nomogram prediction model with the existing scoring systems.

METHODS

Included in this study were 84 SMPCa patients who were admitted in our spinal tumor center between 2006 and 2018. Their clinical data were retrospectively analyzed by univariate and multivariate analyses to identify independent variables that enabled to predict prognosis. A nomogram, named Changzheng Nomogram for Survival Prediction (CNSP), was established on the basis of preoperative independent variables, and then subjected to bootstrap re-samples for internal validation. The predictive accuracy and discriminative ability were measured by concordance index (C-index). Receiver-operating characteristic (ROC) analysis with the corresponding area under the ROC was used to estimate the prediction efficacy of CNSP and compare it with the four existing prognostic models Tomita, Tokuhashi, Bauer, and Crnalic.

RESULTS

A total of seven independent variables including Gleason score (P = 0.001), hormone refractory (P < 0.001), visceral metastasis (P < 0.001), lymphocyte to monocyte ratio (P = 0.009), prostate-specific antigen (P = 0.018), fPSA/tPSA (P = 0.029), Karnofsky Performance Status (P = 0.039) were identified after accurate analysis, and then entered the nomogram with the C-index of 0.87 (95% confidence interval, 0.84-0.90). The calibration curves for probability of 12-, 24-, and 36-month overall survival (OS) showed good consistency between the predictive risk and the actual risk. Compared with the previous prognostic models, the CNSP model was significantly more effective than the four existing prognostic models in predicting OS of the SMPCa patients (p < 0.05).

CONCLUSION

The overall performance of the CNSP model was satisfactory and could be used to estimate the survival outcome of individual patients more precisely and thus help clinicians design more specific and individualized therapeutic regimens.Level of Evidence: 4.

Low-Dose MDCT of Patients With Spinal Instrumentation Using Sparse Sampling: Impact on Metal Artifacts

OBJECTIVE. The purpose of our study was to evaluate simulated sparse-sampled MDCT combined with statistical iterative reconstruction (SIR) for low-dose imaging of patients with spinal instrumentation. MATERIALS AND METHODS. Thirty-eight patients with implanted hardware after spinal instrumentation (24 patients with short- or long-term instrumentation-related complications [i.e., adjacent segment disease, screw loosening or implant failure, or postoperative hematoma or seroma] and 14 control subjects with no complications) underwent MDCT. Scans were simulated as if they were performed with 50% (P50), 25% (P25), 10% (P10), and 5% (P5) of the projections of the original acquisition using an in-house-developed SIR algorithm for advanced image reconstructions. Two readers performed qualitative image evaluations of overall image quality and artifacts, image contrast, inspection of the spinal canal, and diagnostic confidence (1 = high, 2 = medium, and 3 = low confidence). RESULTS. Although overall image quality decreased and artifacts increased with reductions in the number of projections, all complications were detected by both readers when 100% of the projections of the original acquisition (P100), P50, and P25 imaging data were used. For P25 data, diagnostic confidence was still high (mean score ± SD: reader 1, 1.2 ± 0.4; reader 2, 1.3 ± 0.5), and interreader agreement was substantial to almost perfect (weighted Cohen κ = 0.787-0.855). The mean volumetric CT dose index was 3.2 mGy for P25 data in comparison with 12.6 mGy for the original acquisition (P100 data). CONCLUSION. The use of sparse sampling and SIR for low-dose MDCT in patients with spinal instrumentation facilitated considerable reductions in radiation exposure. The use of P25 data with SIR resulted in no missed complications related to spinal instrumentation and allowed high diagnostic confidence, so using only 25% of the projections is probably enough for accurate and confident diagnostic detection of major instrumentation-related complications.

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.

Surgical Treatment and Proposed Modified Classification for Harrington Class III Periacetabular Metastases

Objectives

This study aims to: (i) evaluate the outcome of patients with Harrington class III lesions who were treated according to Harrington classification; (ii) propose a modified surgical classification for Harrington class III lesions; and (iii) assess the efficiency of the proposed modified classification.

Methods

This study composes two phases. During phase 1 (2006 to 2011), the clinical data of 16 patients with Harrington class III lesions who were treated by intralesional excision followed by reconstruction of antegrade/retrograde Steinmann pins/screws with cemented total hip arthroplasty (Harrington/modified Harrington procedure) were retrospectively reviewed and further analyzed synthetically to design a modified surgical classification system. In phase 2 (2013 to 2019), 62 patients with Harrington class III lesions were classified and surgically treated according to our modified classification. Functional outcome was assessed using the Musculoskeletal Tumor Society (MSTS) 93 scoring system. The outcome of local control was described using 2‐year recurrence‐free survival (RFS). Owing to the limited sample size, we considered P < 0.1 as significant.

Results

In phase 1, the mean surgical time was 273.1 (180 to 390) min and the mean intraoperative hemorrhage was 2425.0 (400.0 to 8000.0) mL, respectively. The mean follow‐up time was 18.5 (2 to 54) months. Recurrence was found in 4 patients and the 2‐year RFS rate was 62.4% (95% confidence interval [CI] 31.6% to 93.2%). The mean postoperative MSTS93 score was 56.5% (20% to 90%). Based on the periacetabular bone destruction, we categorized the lesions into two subgroups: with the bone destruction distal to or around the inferior border of the sacroiliac joint (IIIa) and the bone destruction extended proximal to inferior border of the sacroiliac joint (IIIb). Six patients with IIIb lesions had significant prolonged surgical time (313.3 vs 249.0 min, P = 0.022), massive intraoperative hemorrhage (3533.3 vs 1760.0 mL, P = 0.093), poor functional outcome (46.7% vs 62.3%, P = 0.093), and unfavorable local control (31.3% vs 80.0%, P = 0.037) compared to the 10 patients with IIIa lesions. We then modified the surgical strategy for two subgroup of class III lesions: Harrington/modified Harrington procedure for IIIa lesions and en bloc resection followed by modular hemipelvic endoprosthesis replacement for IIIb lesions. Using the proposed modified surgical classification, 62 patients in the phase 2 study demonstrated improved surgical time (245.3 min, P = 0.086), intraoperative hemorrhage (1466.0 mL, P = 0.092), postoperative MSTS 93 scores (65.3%, P = 0.067), and 2‐year RFS rate (91.3%, P = 0.002) during a mean follow‐up time of 19.9 (1 to 60) months compared to those in the phase 1 study.

Conclusion

The Harrington surgical classification is insufficient for class III lesions. We proposed modification of the classification for Harrington class III lesions by adding two subgroups and corresponding surgical strategies according to the involvement of bone destruction. Our proposed modified classification showed significant improvement in functional outcome and local control, along with acceptable surgical complexity in surgical management for Harrington class III lesions.

Predicting postoperative quality-of-life outcomes in patients with metastatic spine disease: who benefits?

Symptomatic spinal metastasis occurs in around 10% of all cancer patients, 5%-10% of whom will require operative management. While postoperative survival has been extensively evaluated, postoperative health-related quality-of-life (HRQOL) outcomes have remained relatively understudied. Available tools that measure HRQOL are heterogeneous and may emphasize different aspects of HRQOL. The authors of this paper recommend the use of the EQ-5D and Spine Oncology Study Group Outcomes Questionnaire (SOSGOQ), given their extensive validation, to capture the QOL effects of systemic disease and spine metastases. Recent studies have identified preoperative QOL, baseline functional status, and neurological function as potential predictors of postoperative QOL outcomes, but heterogeneity across studies limits the ability to derive meaningful conclusions from the data. Future development of a valid and reliable prognostic model will likely require the application of a standardized protocol in the context of a multicenter study design.

The Clinical Characteristics and Prediction Nomograms for Primary Spine Malignancies

Background

Primary spine malignancies (PSMs) are relatively rare in bone tumors. Due to their rarity, the clinical characteristics and prognostic factors are still ambiguous. In this study, we aim to identify the clinical features and proposed prediction nomograms for patients with PSMs.

Methods

Patients diagnosed with PSMs including chordoma, osteosarcoma, chondrosarcoma, Ewing sarcoma, and malignant giant cell tumor of bone (GCTB) between 1975 and 2016 were selected from the Surveillance, Epidemiology, and End Results (SEER) database. The patient and tumor characteristics were described based on clinical information. The significant prognostic factors of overall survival (OS) and cancer-specific survival (CSS) were identified by the univariate and multivariate Cox analysis. Then, the nomograms for OS and CSS were established based on the selected predictors and their accuracy was explored by the Cox–Snell residual plot, area under the curve (AUC) of receiver operator characteristic (ROC) and calibration curve.

Results

The clinical information of 1,096 patients with PSMs was selected from the SEER database between 1975 and 2016. A total of 395 patients were identified with full survival and treatment data between 2004 and 2016. Chordoma is the commonest tumor with 400 cases, along 172 cases with osteosarcoma, 240 cases with chondrosarcoma, 262 cases with Ewing sarcoma and 22 cases with malignant GCTB. The univariate and multivariate analyses revealed that older age (Age > 60), distant metastasis, chemotherapy, and Surgery were independent predictors for OS and/or CSS. Based on these results, the nomograms were established with a better applicability (AUC for CSS: 0.784; AUC for OS: 0.780).

Conclusions

This study provides the statistics evidence for the clinical characteristics and predictors for patients with PSMs based on a large size population. Additionally, precise prediction nomograms were also established with a well-applicability.

Surgical Impacts of Metastatic Non-small Cell Lung Cancer to the Thoracic and Lumbar Spine

BACKGROUND

Surgery for spinal metastasis is rapidly increasing in frequency with procedures ranging from laminectomy to spondylectomy combined with stabilization. This study investigated the effect of various surgical procedures for spinal metastasis of non-small cell lung cancer (NSCLC).

METHODS

A single-center consecutive series of patients who underwent surgery for spinal metastasis of NSCLC were retrospectively reviewed. Patients' characteristics, radiographic parameters, operative data, clinical outcomes, and complications were analyzed. Surgical outcomes were assessed according to pain and performance status before and after surgery. Overall survival (OS) rate was estimated using the Kaplan-Meier method. Multivariate analysis was performed to detect factors independently associated with OS using a Cox proportional hazards model.

RESULTS

Twenty-one patients were treated with laminectomy, 24 with corpectomy, 13 with spondylectomy (piecemeal or total en bloc fashion), and all procedures were combined with stabilization. Back pain and performance status improved significantly after surgical treatment among the three groups. Revision surgery due to tumor progression at the index level or spinal metastasis at another level were four patients (19.0%) in the laminectomy group, six patients (25.0%) in the corpectomy group, and one patient (7.7%) in the spondylectomy group. A Charlson comorbidity index and the number of spinal metastasis negatively affected OS (hazard ratio [HR], 19.613 and 2.244). Postoperative chemotherapy, time to metastasis, spondylectomy, and corpectomy had favorable associations with OS (HR, 0.455, 0.487, 0.619, and 0.715, respectively).

CONCLUSION

Postoperative chemotherapy was the most critical factor in OS of patients with metastatic NSCLC to the spine. An extensive surgical procedure (corpectomy/spondylectomy) with stabilization also could be beneficial for limited patients with spinal metastasis of NSCLC.

Spine metastasis in patients with prostate cancer: Survival prognosis assessment

BACKGROUND

Patients presenting spine metastasis (SpM) from prostate cancer (PC) form a heterogeneous population, through this study, we aimed to clarify and update their prognostic assessment.

METHODS

The patient data used in this study was obtained from a French national multicenter database of patients treated for PC with SpM between 2014 and 2017. A total of 72 patients and 365 SpM cases were diagnosed.

RESULTS

The median overall survival time for all patients following the event of SpM was 28.8 months. First, we identified three significant survival prognostic factors of PC patients with SpM: good Eastern Cooperative Oncology Group/World Health Organization personnel status (Status 0 hazard ratio [HR]: 0.031, 95% confidence interval [CI]: 0.008-0.127; p < .0001) or (Status 1 HR: 0.163, 95% CI: 0.068-0.393; p < .0001) and SpM radiotherapy (HR: 2.923, 95% CI: 1.059-8.069; p < .0001). Secondly, the presence of osteolytic lesions of the spine (vs. osteoblastic) was found to represent an independent prognosis factor for longer survival [HR: 0.424, 95% CI: 0.216-0.830; p = .01]. Other factors including the number of SpM, surgery, extraspinal metastasis, synchrone metastasis, metastasis-free survival, and SpM recurrence were not identified as being prognostically relevant to the survival of patients with PC.

CONCLUSION

Survival and our ability to estimate it in patients presenting PC with SpM have improved significantly. Therefore, we advocate the relevance of updating SpM prognostic scoring algorithms by incorporating data regarding the timeline of PC as well as the presence of osteolytic SpM to conceive treatments that are adapted to each patient.

A Novel Clinical Scoring System for Perioperative Morbidity in Metastatic Spinal Tumor Surgery: The Spine Oncology Morbidity Assessment Score

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To evaluate a scoring system to predict morbidity for patients undergoing metastatic spinal tumor surgery (MSTS).

SUMMARY OF BACKGROUND DATA

Multiple scoring systems exist to predict survival for patients with spinal metastasis. The potential benefits and risks of surgery need to be evaluated for patients with disseminated cancer and limited life expectancy. Few scoring systems exist to predict perioperative morbidity after MSTS.

METHODS

We reviewed records of patients who underwent MSTS at our institution between 2013 and 2019. All perioperative complications occurring within 30 days were recorded. A clinical scoring system consisting of five variables (age ≥ 70 yr, hypoalbuminemia, poor preoperative functional status [Karnofsky ≤ 40], Frankel Grade A-C, and multilevel disease ≥2 continuous vertebral bodies) was evaluated as a predictive tool for morbidity; every parameter was assigned a value of 0 if absent or 1 if present (total possible score = 5). The effect of the scoring system on morbidity was evaluated using stepwise multiple logistic regression. Model accuracy was calculated by receiver operating characteristic analysis.

RESULTS

One hundred and five patients were identified, with a male prevalence of 58.1% and average age at surgery of 61 years. The overall 30-day complication rate was 36.2%. The perioperative morbidity was 4.6%, 30.0%, 53.9%, and 64.7% for patients with scores of 0, 1, 2, and ≥3 points, respectively (P < 0.001). On multiple logistic regression analysis controlling for covariates not present in the model, the scoring system was significantly associated with 30-day morbidity (OR 3.11; 95% CI, 1.72-5.59; P < 0.001). The model's accuracy was estimated at 0.75.

CONCLUSION

Our proposed model was found to accurately predict perioperative morbidity after MSTS. The Spine Oncology Morbidity Assessment (SOMA) score may prove useful for risk stratification and possibly decision-making, though further validation is needed.Level of Evidence: 4.