Classification and scoring systems for metastatic spine tumors: a literature review

Management of Metastatic Spinal Disease - A Practical Approach

STUDY DESIGN

Narrative review.

OBJECTIVE

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

METHODS

N/A.

RESULTS

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

CONCLUSION

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

Safety and feasibility of ultra-long construct navigated minimally invasive spine surgery with adjuvant radiotherapy in extensive spinal metastasis : a comparative analysis

BACKGROUND

Our study compares the outcomes of extensive spinal metastasis patients treated with Ultra-Long Construct Navigated Minimally Invasive Spine Surgery (UNMISS) with Adjuvant Radiotherapy to those receiving only radiotherapy. Spinal metastasis often necessitates interventions like radiotherapy, chemotherapy, or surgery, with an increasing trend towards surgical management. minimally invasive spine surgery has demonstrated advantages over traditional open surgery, with fewer complications and better postoperative outcomes. Radiotherapy continues as a standard for those unsuitable for surgery.

METHODS

This retrospective study included extensive spinal metastasis patients treated between January 2017 and December 2020. We compared patients undergoing UNMISS in conjunction with radiotherapy to patients receiving radiotherapy alone, evaluating demographic data, disease characteristics, and treatment outcomes (VAS, survival) to establish statistical significance.

RESULTS

Twenty-three patients were included in our study. Fourteen patients underwent UNMISS, and nine patients received radiotherapy alone. There was no difference in baseline characteristics of patients. The longest construct in our case series involved T1 to iliac. Both cohorts showed significant improvement in pain scores post-treatment (p = 0.01). However, the UNMISS group demonstrated significantly lower post-treatment VAS scores (p = 0.003), indicating enhanced pain relief. Survival outcomes did not differ significantly between the two groups.

CONCLUSION

The UNMISS should be considered as an alternative treatment in a patient with symptomatic extensive spinal metastasis. The primary goal of this technique is to stabilize the multiple levels of spinal metastasis and decompression of the neural element if needed. This technique is safe and has a better outcome in pain improvement than the patient who received radiotherapy alone.

[Translated article] The role of minimally invasive spine surgery in the treatment of vertebral metastasis (Part 1): A clinical review

Spinal metastases represent a significant burden on the quality of life in patients affected by active oncological disease due to the high incidence of pain syndromes, spinal deformity, and neurological impairment. Surgery plays a decisive role in improving quality of life by controlling pain, restoring neurological function and maintaining spinal stability, as well as contributing to the response to medical therapy. Minimally invasive surgery (MIS) is a treatment option in certain patients with high surgical risk since it has a low rate of complications, intraoperative bleeding, hospital stay, and offers similar results to open surgery. In this review, we present the role of MIS in this pathology and some cases treated in our hospital.

The role of minimally invasive spine surgery in the treatment of vertebral metastasis (part 1): A clinical review

Spinal metastases represent a significant burden on the quality of life in patients affected by active oncological disease due to the high incidence of pain syndromes, spinal deformity, and neurological impairment. Surgery plays a decisive role in improving quality of life by controlling pain, restoring neurological function and maintaining spinal stability, as well as contributing to the response to medical therapy. Minimally invasive surgery (MIS) is a treatment option in certain patients with high surgical risk since it has a low rate of complications, intraoperative bleeding, hospital stay, and offers similar results to open surgery. In this review, we present the role of MIS in this pathology and some cases treated in our hospital.

Management of vertebral metastases in the cervico-occipital junction

Occipito-cervical metastases correspond to 0.5% of spinal metastases. The management of these lesions is complex and involves multiple radiological studies, such as simple radiology, computed tomography (CT), magnetic resonance imaging (MRI). Is vascular involvement is suspected, tests to assess vascular permeability are also recommended (angioCT). This type of lesion, due to its complex location, may require different types of approaches, commonly it will be the posterior approach, but sometimes anterior or anterolateral approaches will be needed assisted by maxillofacial surgeons or otorhinolaryngologists for correct excision of the tumor. Pain with head turning can guide us to the diagnosis in an unstable spine. Magnetic resonance is the test of choice to diagnose and study these lesions. The presence of instability or progressive neurological symptoms are an indication for surgery.

[Translated article] Management of vertebral metastases in the cervico-occipital junction

Occipito-cervical metastases correspond to 0.5% of spinal metastases. The management of these lesions is complex and involves multiple radiological studies, such as simple radiology, computed tomography (CT), magnetic resonance imaging (MRI). Is vascular involvement is suspected, tests to assess vascular permeability are also recommended (angioCT). This type of lesion, due to its complex location, may require different types of approaches, commonly it will be the posterior approach, but sometimes anterior or antero-lateral approaches will be needed assisted by maxillofacial surgeons or otorhinolaryngologists for correct excision of the tumour. Pain with head turning can guide us to the diagnosis in an unstable spine. Magnetic resonance is the test of choice to diagnose and study these lesions. The presence of instability or progressive neurological symptoms is an indication for surgery.

Multiple Myeloma Spinal Lesion Care: Management of a Primary Bone Malignancy Rather Than a Spinal Metastasis

OBJECTIVE

Multiple myeloma (MM) is too often wrongly categorized as a spinal metastasis (SpM), although it is distinguishable from SpM in many aspects, such as its earlier natural history at the time of diagnosis, its increased overall survival (OS), and its response to therapeutic modalities. The characterization of these 2 different spine lesions remains a main challenge.

METHODS

This study compares 2 consecutive prospective oncologic populations of patients with spine lesions: 361 patients treated for MM spine lesions and 660 patients treated for SpM between January 2014 and 2017.

RESULTS

The mean time between the tumor/MM diagnosis and spine lesions was respectively 0.3 (standard deviation [SD] 4.1) and 35.1 months (SD 21.2) for the MM and SpM groups. The median OS for the MM group was 59.6 months (SD 6.0) versus 13.5 months (SD 1.3) for the SpM group (P < 0.0001). Regardless of Eastern Cooperative Oncology Group (ECOG) performance status, patients with MM always have a significantly better median OS than do patients with SpM: ECOG 0, 75.3 versus 38.7 months; ECOG 1, 74.3 versus 24.7 months; ECOG 2, 34.6 versus 8.1 months; ECOG 3, 13.5 versus 3.2 months and ECOG 4, 7.3 versus 1.3 months (P < 0.0001). The patients with MM had more diffuse spinal involvement (mean, 7.8 lesions; SD 4.7) than did patients with SpM (mean, 3.9; SD 3.5) (P < 0.0001).

CONCLUSIONS

MM must be considered as a primary bone tumor, not as SpM. The strategic position of the spine in the natural course of cancer (i.e., nurturing cradle of birth for MM vs. systemic metastases spreading for SpM) explains the differences in OS and outcome.

Nutritional Status Is Associated With Survival Following Spinal Surgery in Patients With Metastatic Spinal Tumors

Background Preoperative and postoperative nutritional statuses are reported to influence the outcomes and complications of multidisciplinary treatment, including patient survival. However, a causal relationship between nutritional status and survival following spinal surgery has not been demonstrated in patients with metastatic spinal tumors. The present study was, therefore, designed to evaluate the correlation between the nutritional status and survival following spinal surgery in patients with metastatic spinal tumors. Methods Nutritional status was evaluated using the Japanese version of the modified Glasgow prognostic score (JmGPS), C-reactive protein-to-albumin ratio (CAR), prognostic nutrition index (PNI), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR), which were calculated from the results of preoperative laboratory tests. The survival period was defined as the interval between the day preoperative data were obtained and the day of death. Results Data from 57 of 113 consecutive surgeries were retrieved. The CAR, JmGPS, and PNI were significantly correlated with the survival period (CAR, r = -0.576, P < 0.01; JmGPS, r = -0.537, P < 0.01; PNI, r = 0.316, P = 0.02). Furthermore, patients with 0 points on the JmGPS had significantly longer survival. Using receiver operating characteristic curves, CAR cutoffs of ≥0.880 and ≤0.220 were found to be optimal in predicting the 90- and 180-day postoperative survival, respectively. Conclusions The findings of the present study indicate that preoperative assessment of the JmGPS, CAR, and PNI has utility in estimating nutritional status and predicting survival following spinal surgery in patients with metastatic spinal tumors.

Primary Osseous Malignancies of the Spine

Malignant primary vertebral tumours comprise an uncommon group of primary bone malignancies that can pose a diagnostic and therapeutic challenge. The most frequently encountered malignant primary vertebral tumours include chordoma, chondrosarcoma, Ewing sarcoma and osteosarcoma. These tumours often present with nonspecific symptoms, such as back pain, neurologic deficits and spinal instability, which can be confused for the more commonly encountered mechanical back pain and may delay their diagnosis and treatment. Imaging, including radiography, computed tomography (CT) and magnetic resonance imaging (MRI) is crucial for diagnosis, staging, treatment planning and follow-up. Surgical resection remains the mainstay of treatment for malignant primary vertebral tumours, but adjuvant radiotherapy and chemotherapy may be necessary for achieving complete tumour control depending on the type of tumour. In recent years, advances in imaging techniques and surgical approaches, such as en-bloc resection and spinal reconstruction, have improved the outcomes for patients with malignant primary vertebral tumours. However, the management can be complex due to the anatomy involved and the high morbidity and mortality associated with surgery. The different types of malignant primary vertebral lesions will be discussed in this article with an emphasis on the imaging features.

The Management of Metastatic Spinal Cord Compression in Routine Clinical Practice

(1) Background: Whether clinical management of spinal metastatic disease (SMD) matches evidence-based recommendations is largely unknown. (2) Patients and Methods: A questionnaire was distributed through Spanish Medical Societies, exploring routine practice, interpretation of the SINS and ESCC scores and agreement with items in the Tokuhashi and SINS scales, and NICE guideline recommendations. Questionnaires were completed voluntarily and anonymously, without compensation. (3) Results: Eighty specialists participated in the study. A protocol for patients with SMD existed in 33.7% of the hospitals, a specific multidisciplinary board in 33.7%, 40% of radiological reports included the ESCC score, and a prognostic scoring method was used in 73.7%. While 77.5% of the participants were familiar with SINS, only 60% used it. The different SINS and ESCC scores were interpreted correctly by 57.5-70.0% and 30.0-37.5% of the participants, respectively. Over 70% agreed with the items included in the SINS and Tokuhashi scores and with the recommendations from the NICE guideline. Differences were found across private/public sectors, hospital complexity, number of years of experience, number of patients with SMD seen annually and especially across specialties. (4) Conclusions: Most specialists know and agree with features defining the gold standard treatment for patients with SCC, but many do not apply them.

Management of pain in patients with bone metastases

Cancer-induced bone pain (CIBP) has a considerable impact on patients’ quality of life as well as physical and mental health. At present, patients with CIBP are managed according to the three-step analgesic therapy algorithm proposed by the World Health Organization. Opioids are commonly used as the first-line treatment for moderate-to-severe cancer pain but are limited due to addiction, nausea, vomiting and other gastrointestinal side effects. Moreover, opioids have a limited analgesic effect in some patients. In order to optimize the management of CIBP, we must first identify the underlying mechanisms. In some patients, surgery, or surgery combined with radiotherapy or radiofrequency ablation is the first step in the management of CIBP. Various clinical studies have shown that anti-nerve growth factor (NGF) antibodies, bisphosphonates, or RANKL inhibitors can reduce the incidence and improve the management of cancer pain. Herein, we review the mechanisms of cancer pain and potential therapeutic strategies to provide insights for optimizing the management of CIBP.

External validation of the SORG machine learning algorithms for predicting 90-day and 1-year survival of patients with lung cancer-derived spine metastases: a recent bi-center cohort from China

BACKGROUND CONTEXT

The survival prediction of lung cancer-derived spinal metastases is often underestimated by several scores. The SORG machine learning (ML) algorithm is considered a promising tool to predict the risk of 90-day and 1-year mortality in patients with spinal metastases, but not been externally validated for lung cancer.

PURPOSE

This study aimed to externally validate the SORG ML algorithms on lung cancer-derived spinal metastases patients from two large-volume, tertiary medical centers between 2018 and 2021.

STUDY DESIGN/SETTING

Retrospective, cohort study.

PATIENT SAMPLE

Patients aged 18 years or older at two tertiary medical centers in China are treated surgically for spinal metastasis.

OUTCOME MEASURES

Mortality within 90 days of surgery, mortality within 1 year of surgery.

METHODS

The baseline characteristics were compared between the development cohort and our validation cohort. Discrimination (receiver operating curve), calibration (calibration plot, intercept, and slope), the overall performance (Brier score), and decision curve analysis was used to assess the overall performance of the SORG ML algorithms.

RESULTS

This study included 150 patients with lung cancer-derived spinal metastases from two medical centers in China. Ninety-day and 1-year mortality rates were 12.9% (19/147) and 51.3% (60/117), respectively. Lung Cancer with targeted therapies had the lowest Hazard Ratio (HR=0.490), showing an optimal protecting factor. The AUC of the SORG ML algorithm for 90-day mortality prediction in lung cancer-derived spinal metastases is 0.714. While the AUC for 1-year mortality prediction is 0.832 (95CI%, 0.758-0.906). The algorithm for 1-year mortality was well-calibrated with an intercept of 0.13 and a calibration slope of 1.00. However, the 90-day mortality prediction was underestimated with an intercept of 0.60 and a slope of 0.37. The SORG ML algorithms for 1-year mortality showed a greater net benefit than the "treats all or no patients" strategies.

CONCLUSIONS

In the latest cohort of lung cancer-derived spinal metastases in China, the SORG algorithms for predicting 1-year mortality performed well on external validation. However, 90-day mortality was underestimated. The algorithm should be further validated by single primary tumor-derived metastasis treated with the latest comprehensive treatment in diverse populations.

DEVELOPMENT OF A MATHEMATICAL MODEL OF SELECTING THE EXTENT OF A SURGICAL INTERVENTION IN SPINAL TUMOR

OBJECTIVE

The aim: To develop a mathematical model of selecting the extent of surgical intervention in the spinal tumors.

PATIENTS AND METHODS

Materials and methods: The retrospective study included 237 patients with spinal tumors who underwent the following surgeries: vertebroplasty (V); vertebroplasty and spinal fixation (F+V); posterior spinal decompression and spinal fixation (F+F); vertebrectomy and replacement of vertebra by a cage with posterior spinal fixation (F+F+K). The mathematical model is based on the modified Spine Instability Neoplastic Score (SINS). The patients were divided into two clusters. Cluster analysis was used to build a diagnostic decision tree model.

RESULTS

Results: The difference between two clusters is determined by the extent of surgical intervention, the grade of the vertebral lesion, epidural compression, and local kyphosis, and neurological signs as well. The cluster 1 included 115 patients with higher values of SINS compared to the cluster 2. All cases of vertebroplasty belonged to the cluster 2. In the cluster 1 cases of surgery of large extent: F+F; F+V; F+F+K. Analysis of the decision tree model for cluster 1 showed that a type of surgery was determined for 97 patients from 115 that relates to 84.3% of overall accuracy. The decision tree model have a high predictive accuracy for the surgery F+V and better indicators of coverage and predictive accuracy for the surgery F+F+K.

CONCLUSION

Conclusions: Our study developed a decision tree model to optimize spinal neoplasm surgery, achieving 84.3% accuracy based on significant prognosis criteria. The model considers surgical type, neurological signs, vertebra lesion grade, and stage of epidural compression, potentially improving clinical outcomes.

Characterization and Treatment of Spinal Tumors

The prevalence of spinal tumors is rare in comparison to brain tumors which encompass most central nervous system tumors. Tumors of the spine can be divided into primary and metastatic tumors with the latter being the most common presentation. Primary tumors are subdivided based on their location on the spinal column and in the spinal cord into intramedullary, intradural extramedullary, and primary bone tumors. Back pain is a common presentation in spine cancer patients; however, other radicular pain may be present. Magnetic resonance imaging (MRI) is the imaging modality of choice for intradural extramedullary and intramedullary tumors. Plain radiographs are used in the initial diagnosis of primary bone tumors while Computed tomography (CT) and MRI may often be necessary for further characterization. Complete surgical resection is the treatment of choice for spinal tumors and may be curative for well circumscribed lesions. However, intralesional resection along with adjuvant radiation and chemotherapy can be indicated for patients that would experience increased morbidity from damage to nearby neurological structures caused by resection with wide margins. Even with the current treatment options, the prognosis for aggressive spinal cancer remains poor. Advances in novel treatments including molecular targeting, immunotherapy and stem cell therapy provide the potential for greater control of malignant and metastatic tumors of the spine.

Intramedullary spinal cord metastasis to the cauda equina in a patient with HER2-positive metastatic breast cancer: A case report

The rate of metastasis to the central nervous system is high in human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer patients. Metastatic cauda equina tumors are characterized by rapid progression of symptoms, thus signifying the requirement of their early treatment. However, these tumors are rarely reported, and their optimal treatment options have not been established yet. Here, we report a case study of a patient with HER2-positive breast cancer that metastasized to the cauda equina. The patient underwent urgent surgery to relieve the spinal cord compression. The pain in her back and lower limbs was greatly reduced. Unfortunately, her ability to walk did not improve sufficiently. Overall, surgical treatment may be a favorable option to improve a patient's quality of life.

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.

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.

Metastatic Renal Cell Carcinoma to the Spine: Outcomes and Morbidity: Single-Center Experience

BACKGROUND

Renal cell carcinoma with metastases to the spine (RCCMS) requires a multidisciplinary approach. We reviewed our institutional experience with RCCMS patients undergoing spinal surgery in order to identify factors that may affect clinical outcomes, survival, and complications.

METHODS

Patients with RCCMS who underwent operative intervention from 2007 to 2020 were reviewed retrospectively.

RESULTS

Forty-four patients with the diagnosis of RCCMS were identified. Pain was the most common symptom, and neurologic dysfunction was present in one third of cases. Thoracic spine was the most common location (N = 27), followed by the lumbar (N = 12) and cervical (N = 5) regions. The overall survival from diagnosis of renal cell carcinoma was 25 (2 - 194) months and 8 (0.3 - 92) months after spinal surgery. Gender, age, spinal level, postoperative radiation, and nephrectomy had no bearing on survival. Survival for patients with a Tokuhashi score of 0 - 8, 9 - 11, and 12 - 15 was 6.5 (1.5 - 23.5), 8.9 (0.3 - 91.6), and 23.4 (2.5 - 66) months, respectively (P = 0.03). The postoperative American Spinal Cord Injury Association score of E (hazard ratio 0.109 [95% confidence interval 0.022 - 0.534, P = 0.006) also bore a significant influence on survival. There was a total of 10 complications in 7 of 44 (16%) patients.

CONCLUSIONS

Median postoperative survival of patients with RCCMS was 8 (0.3 - 92) months. Higher Tokuhashi score and ASIA E score at follow-up correlated with improved overall survival. Complication rate was 16%. Spinal surgery in RCCMS is indicated for the preservation of function and prevention of neurologic deterioration. Multimodality therapy with improved chemotherapy and stereotactic spinal radiation is expected to impact quality and length of survival positively.

Scoring Algorithms for Predicting Survival Prognosis in Patients With Metastatic Spinal Disease: The Current Status and Future Directions

Various survival scoring systems have been developed to help surgeons select the best candidates for appropriate therapies in patients with metastatic spinal disease. This study aims to discuss the current status and future directions of scoring systems for the prediction of survival prognosis in these patients. The search terms "spine metastases," "metastatic spinal disease," and "metastatic spinal cord compression" were combined with "survival prognosis," "scoring system," and "score" to elicit relevant literatures in PubMed and Embase databases. As a result, 159 articles were selected from PubMed, and 246 articles were extracted from Embase. After reviewing each article, we carefully included and analyzed 74 articles about the development and evaluation of scoring systems for predicting survival prognosis in spine metastases. In this review, those scoring systems were stratified into the historic scoring systems and the modern scoring systems on the basis of the proposed time. The historic scoring systems, including the original/revised Tokuhashi scoring system, the Bauer scoring system, the Tomita scoring system, and the Linden scoring system, and the modern scoring systems, such as the Lei scoring system, the Bartels scoring system, the Mizumoto scoring system, the Bollen scoring system, the Rades scoring system, Oswestry Spinal Risk Index, and the Choi risk calculator, were introduced and discussed in this review. Besides, the clinical effectiveness and pitfalls of the existing systems and the future directions of the next generation of scoring systems were also addressed and discussed. We recommended these scoring systems as preferable reference tools to help doctors to select surgical candidates. In patients with long-term life expectancy, radical surgery, such as wide or marginal excision, can be considered in patients with neurological deficits, spine instability, or severe back pain. Besides, with the advancement and improvement of medical technologies, surgical procedures are changing, which can affect surgical indications such as vertebroplasty, minimal invasive surgery, and percutaneous stabilization, which can also be used in patients with spine instability or severe back pain, and do not require much recovery; hence, they can even be used in patients with relative short-term life expectancy. However, the decision about the treatment of patients with metastatic spinal disease is so complicated and should never rely on prognostic scores alone. The final therapeutic decision should be made by interdisciplinary corporations of oncologists, radiologists, and spinal surgeons. Besides, individual intentions should be respected.

Intradural metastasis to the cauda equina found as the initial presentation of breast cancer: a case report

BACKGROUND

Intradural extramedullary spinal metastasis is a relatively rare condition. Furthermore, there are few reports with the initial presentation being a neurological symptom from an intradural metastasis. We report a case of a patient with metastasis to the cauda equina from breast cancer found due to neurological symptoms as the initial presentation.

CASE PRESENTATION

A 76-year-old Japanese woman who was previously healthy presented to our hospital with bilateral severe buttock and lower extremity pain without any history of injury. A solitary intradural cauda equina mass was found by magnetic resonance imaging at the L2/3 level, and we suspected a schwannoma initially. The patient hoped to undergo surgery due to the severe pain. However, the chest computed tomographic scan obtained to assess the patient's general status showed the suspected breast cancer of the left side and a lung metastasis. Hence, we considered the possibility of cauda equina tumor metastatic from the breast cancer. We performed an L1-3 laminectomy and tumor extirpation. The pathology revealed adenocarcinoma. After surgery, she had relief from pain, and her status remained satisfactory until she died 9 months after surgery.

CONCLUSIONS

It is difficult to clarify whether the cauda equina tumor is benign or malignant based only on Magnetic resonance imaging findings. Clinicians should consider the possibility of metastasis when planning the surgery for intradural cauda equina tumor extirpation.

Kidney and Thyroid Cancer-Specific Treatment Algorithm for Spinal Metastases: A Validation Study

BACKGROUND

Spinal metastases (SMs) from kidney and thyroid cancers have several common features suggesting that excisional surgery for isolated and removable SMs can improve survival. We propose a simple treatment algorithm for SMs from these cancers. Our study aimed to evaluate the efficacy of the algorithm.

METHODS

We performed a retrospective analysis of the data of 69 consecutive patients (48 with kidney and 21 with thyroid cancers) who underwent excisional surgery for SMs between 1995 and 2014. The patients were retrospectively classified into an indicated group for excisional SM surgery and a nonindicated group according to our algorithm, and the Tokuhashi and Tomita scoring systems. Patients in the indicated group were expected to survive ≥2 years postoperatively, whereas those in the nonindicated group were not. The positive predictive value and negative predictive value (NPV) were calculated using the predicted versus actual survival times of the patients. Survival was defined as the time from the first excisional surgery for the spinal lesion to death or the last follow-up of ≥2 years.

RESULTS

For patients with kidney cancer, the 2- and 5-year survival rates were 85.4% and 60.4%, respectively. For patients with thyroid cancer, the 2- and 5-year survival rates were 100% and 83.8%, respectively. Our algorithm had a compatible high positive predictive value (95.5%) and NPV (100%), whereas the Tokuhashi and Tomita scoring systems had low NPVs of 15.8% and 13.3%, respectively.

CONCLUSIONS

Our treatment algorithm of SMs from kidney and thyroid cancers is useful for determining an adequate treatment including excisional surgery.