Classifications in Brief: The Spinal Instability Neoplastic Score.

113. Correlation between the spinal instability neoplastic score (SINS) and patient reported outcomes

Study Design:International multicenter prospective observational cohort study on patients undergoing radiation +/− surgical intervention for the treatment of symptomatic spinal metastases.Objectives:To investigate the association between the total Spinal Instability Neoplastic Score (SINS), individual SINS components and PROs.Methods:Data regarding patient demographics, diagnostics, treatment, and PROs (SF-36, SOSGOQ, EQ-5D) was collected at baseline, 6 weeks, and 12 weeks post-treatment. The SINS was assessed using routine diagnostic imaging. The association between SINS, PRO at baseline and change in PROs was examined with the Spearmans rank test.Results:A total of 307 patients, including 174 patients who underwent surgery+/− radiotherapy and 133 patients who underwent radiotherapy were eligible for analyses. In the surgery+/− radiotherapy group, 18 (10.3%) patients with SINS score between 0-6, 118 (67.8%) with a SINS between 7-12 and 38 (21.8%) with a SINS between 13-18, as compared to 55 (41.4%) SINS 0-6, 71(53.4%) SINS 7-12 and 7 (5.2%) SINS 13-18 in the radiotherapy alone group. At baseline, the total SINS and the presence of mechanical pain was significantly associated with the SOSGOQ pain domain (r = −0.519, P < 0.001) and the NRS pain score (r = 0.445, P < 0.001) for all patients. The presence of mechanical pain demonstrated to be moderately associated with a positive change in PROs at 12 weeks post-treatment.Conclusion:Spinal instability, as defined by the SINS, was significantly correlated with PROs at baseline and change in PROs post-treatment. Mechanical pain, as a single SINS component, showed the highest correlations with PROs.

BackgroundThe Spinal Instability Neoplastic Score (SINS) categorizes tumor related spinal instability. It has the potential to streamline the referral of patients with established or potential spinal instability to a spine surgeon. This study aims to define the inter- and intra-observer reliability and validity of SINS among radiation oncologists.MethodsThirty-three radiation oncologists, across ten international sites, rated 30 neoplastic spinal disease cases. For each case, the total SINS (0-18 points), three clinical categories (stable: 0-6 points, potentially unstable: 7-12 points, and unstable: 13-18 points), and a binary scale (‘stable’: 0-6 points and ‘current or possible instability’; surgical consultation recommended: 7-18 points) were recorded. Evaluation was repeated 6-8 weeks later. Inter-observer agreement and intra-observer reproducibility were calculated by means of the kappa statistic and translated into levels of agreement (slight, fair, moderate, substantial, and excellent). Validity was determined by comparing the ratings against a spinal surgeon’s consensus standard.ResultsRadiation oncologists demonstrated substantial (κ = 0.76) inter-observer and excellent (κ = 0.80) intra-observer reliability when using the SINS binary scale (‘stable’ versus ‘current or possible instability’). Validity of the binary scale was also excellent (κ = 0.85) compared with the gold standard. None of the unstable cases was rated as stable by the radiation oncologists ensuring all were appropriately recommended for surgical consultation.ConclusionsAmong radiation oncologists SINS is a highly reliable, reproducible, and valid assessment tool to address a key question in tumor related spinal disease: Is the spine ‘stable’ or is there ‘current or possible instability’ that warrants surgical assessment?

Simple SummarySpinal epidural metastases are a common complication of malignancies that can compromise spinal stability and subsequently lead to neurologic deficits in addition to pain and overall reduced quality of life, often requiring spinal instrumentation. The spinal instability neoplastic score is an instrument used to evaluate spinal stability; a stable situation is assumed in cases of a SINS below 7 and instability in cases of a SINS above 12, but there is uncertainty in SINS 7 to 12. Our aim was to evaluate the benefit of spinal instrumentation in these cases in terms of neurological function in order to improve patient treatment.Background: Adequate assessment of spinal instability using the spinal instability neoplastic score (SINS) frequently guides surgical therapy in spinal epidural osseous metastases and subsequently influences neurological outcome. However, how to surgically manage ‘impending instability’ at SINS 7–12 most appropriately remains uncertain. This study aimed to evaluate the necessity of spinal instrumentation in patients with SINS 7–12 with regards to neurological outcome. Methods: We screened 683 patients with spinal epidural metastases treated at our interdisciplinary spine center. The preoperative SINS was assessed to determine spinal instability and neurological status was defined using the Frankel score. Patients were dichotomized according to being treated by instrumentation surgery and neurological outcomes were compared. Additionally, a subgroup analysis of groups with SINS of 7–9 and 10–12 was performed. Results: Of 331 patients with a SINS of 7–12, 76.1% underwent spinal instrumentation. Neurological outcome did not differ significantly between instrumented and non-instrumented patients (p = 0.612). Spinal instrumentation was performed more frequently in SINS 10–12 than in SINS 7–9 (p < 0.001). The subgroup analysis showed no significant differences in neurological outcome between instrumented and non-instrumented patients in either SINS 7–9 (p = 0.278) or SINS 10–12 (p = 0.577). Complications occurred more frequently in instrumented than in non-instrumented patients (p = 0.016). Conclusions: Our data suggest that a SINS of 7–12 alone might not warrant the increased surgical risks of additional spinal instrumentation.

Role of Spinal Instability Neoplastic Score in Management of Spinal Plasmacytoma

The objective of the different types of treatments for a spinal metastasis is to provide the best oncological and functional result with the least aggressive side effects. Initially created in 2010 to help clinicians in the management of vertebral metastases, the Spine Instability Neoplastic Score (SINS) has quickly found its place in the decision making and the treatment of patients with metastatic spinal disease. Here we conduct a review of the literature describing the different changes that occurred with the SINS score in the last ten years. After a brief presentation of the spinal metastases’ distribution, with or without spinal cord compression, we present the utility of SINS in the radiological diagnosis and extension of the disease, in addition to its limits, especially for scores ranging between 7 and 12. We take this opportunity to expose the latest advances in surgery and radiotherapy concerning spinal metastases, as well as in palliative care and pain control. We also discuss the reliability of SINS amongst radiologists, radiation oncologists, spine surgeons and spine surgery trainees. Finally, we will present the new SINS-derived predictive scores, biomarkers and artificial intelligence algorithms that allow a multidisciplinary approach for the management of spinal metastases.

Background: Although the Spinal Instability Neoplastic Score (SINS) is widely utilized to evaluate spinal instability, its prognostic value for survival in patients with cervical spinal metastases remains unclear. This study investigated the association between the SINS and survival outcomes in patients with metastatic cervical spine cancer. Methods: This retrospective cohort study included 106 patients who underwent surgery for metastatic cervical spine cancer at a single institution between 1995 and 2023. Patients were divided into two groups: high SINS (≥13) and low-to-moderate SINS (0-12). Overall survival (OS) was the primary outcome and was analyzed using Kaplan-Meier estimates and Cox regression. Secondary outcomes included changes in Eastern Cooperative Oncology Group Performance Status (ECOG-PS), operation time, estimated blood loss, and postoperative complications. Results: The median OS was significantly shorter in the high SINS group compared to the low-to-moderate SINS group (5.3 months versus 8.6 months; p = 0.023). A high SINS was independently associated with increased mortality risk (hazard ratio [HR], 1.959; 95% CI, 1.221-3.143; p = 0.005). Lung cancer (HR, 4.004; 95% CI, 1.878-8.535; p < 0.001) and rectal cancer (HR, 3.293; 95% CI, 1.126-9.632; p = 0.029) were predictive of worse survival, whereas postoperative chemotherapy (HR, 0.591; 95% CI, 0.381-0.917; p = 0.019) and radiotherapy (HR, 0.531; 95% CI, 0.340-0.827; p = 0.005) were associated with improved survival. Changes in the ECOG-PS and postoperative complication rates were not significantly different between the groups. Conclusions: A high SINS was associated with significantly shorter survival in patients with metastatic cervical spine cancer, reflecting both mechanical instability and tumor aggressiveness.

Precise assessment of spinal instability is critical before and after radiotherapy (RT) for evaluating the effectiveness of RT. Therefore, we retrospectively evaluated the efficacy of RT in spinal instability over a period of 6 months after RT, utilizing the spinal instability neoplastic score (SINS) in patients with painful spinal metastasis. We retrospectively evaluated 108 patients who received RT for painful vertebral metastasis in our institution. Mechanical pain at metastatic vertebrae, radiological responses of irradiated vertebrae, and spinal instability were assessed. Follow-up assessments were done at the start of and at intervals of 1, 2, 3, 4, and 6 months after RT, with the pain disappearing in 67%, 85%, 93%, 97%, and 100% of the patients, respectively. The median SINS were 8, 6, 6, 5, 5, and 4 at the beginning and after 1, 2, 3, 4, and 6 months of RT, respectively. Multivariate analysis revealed that posterolateral involvement of spinal elements (PLISE) was the only risk factor for continuous potentially unstable/unstable spine at 1 month. In conclusion, there was improvement of pain, and recalcification results in regaining spinal stability over time after RT although vertebral body collapse and malalignment occur in some irradiated vertebrae. Clinicians should pay attention to PLISE in predicting continuous potentially unstable/unstable spine.

Vertebral compression fracture (VCF) is a common, but serious toxicity of spinal stereotactic body radiotherapy (SBRT). Several variables that place patients at high risk of VCF have previously been identified, including advanced Spinal Instability Neoplastic Score (SINS), a widely adopted clinical decision criterion to assess spinal instability. We examine the role of tumoral endplate (EP) disruption in the risk of VCF and attempt to incorporate it into a simple risk stratification system. This study was a retrospective cohort study from a single institution. Demographic and treatment information was collected for patients who received spinal SBRT between 2013 and 2019. EP disruption was noted on pre-SBRT computed tomography scan. The primary end point of 1-year cumulative incidence of VCF was assessed on follow-up MRI and computed tomography scans at 3-month intervals after treatment. A total of 111 patients were included. The median follow-up was 18 months. Approximately 48 patients (43%) had at least one EP disruption. Twenty patients (18%) experienced a VCF at a median of 5.2 months from SBRT. Patients with at least one EP disruption were more likely to experience VCF than those with no EP disruption (29% vs 6%, P < .001). A nomogram was created using the variables of EP disruption, a SINS of ≥7, and adverse histology. Patients were stratified into groups at low and high risk of VCF, which were associated with 2% and 38% risk of VCF ( P < .001). EP disruption is a novel risk factor for VCF in patients who will undergo spinal SBRT. A simple nomogram incorporating EP disruption, adverse histology, and SINS score is effective for quickly assessing risk of VCF. These data require validation in prospective studies and could be helpful in counseling patients regarding VCF risk and referring for prophylactic interventions in high-risk populations.

The goal of this study was to determine independent risk factors for vertebral compression fracture (VCF) following radiation for metastatic spine disease, including low bone mineral density as estimated by Hounsfield units (HU). A retrospective chart review identified patients with a single vertebral column metastasis treated with radiation therapy, a pretreatment CT scan, and a follow-up CT scan at least 6 weeks after treatment. Patients with primary spine tumors, preradiation vertebroplasty, preradiation spine surgery, prior radiation to the treatment field, and proton beam treatment modality were excluded. The HU were measured in the vertebral bodies at the level superior to the metastasis, within the tumor and medullary bone of the metastatic level, and at the level inferior to the metastasis. Variables collected included basic demographics, Spine Instability Neoplastic Score (SINS), presenting symptoms, bone density treatment, primary tumor pathology, Weinstein-Boriani-Biagini (WBB) classification, Enneking stage, radiation treatment details, chemotherapy regimen, and prophylactic vertebroplasty. One hundred patients with an average age of 63 years and average follow-up of 18 months with radiation treatment dates ranging from 2017 to 2020 were included. Fifty-nine patients were treated with external-beam radiation therapy, with a median total dose of 20 Gy (range 8-40 Gy). Forty-one patients were treated with stereotactic body radiation therapy, with a median total dose of 24 Gy (range 18-39 Gy). The most common primary pathologies included lung (n = 22), prostate (n = 21), and breast (n = 14). Multivariable logistic regression analysis (area under the curve 0.89) demonstrated pretreatment HU (p < 0.01), SINS (p = 0.02), involvement of ≥ 3 WBB sectors (p < 0.01), primary pathology other than prostate (p = 0.04), and ongoing chemotherapy treatment (p = 0.04) to be independent predictors of postradiation VCF. Patients with pretreatment HU < 145 (n = 32), 145-220 (n = 31), and > 220 (n = 37) had a fracture rate of 59%, 39%, and 11%, respectively. An HU cutoff of 157 was found to maximize sensitivity (71%) and specificity (75%) in predicting postradiation VCF. Low preradiation HU, higher SINS, involvement of ≥ 3 WBB sectors, ongoing chemotherapy, and nonprostate primary pathology were independent predictors of postradiation VCF in patients with metastatic spine disease. Low bone mineral density, as estimated by HU, is a novel and potentially modifiable risk factor for VCF.

The aim of this study was to determine independent risk factors for vertebral compression fracture (VCF) following stereotactic body radiation therapy (SBRT) in metastatic spine disease. Patients treated with SBRT for spinal metastasis at a single tertiary care center between 2008 and 2019 were retrospectively identified. Patients with CT scans obtained within 1 year of SBRT completion were included. Variables collected included demographics, Spine Instability Neoplastic Score (SINS), primary tumor pathology, Weinstein-Boriani-Biagini (WBB) classification, chemoradiation treatment details, and bone quality as assessed by Hounsfield units (HUs) on CT. HUs were measured for the medullary bone of the metastatic level, the tumor, and the vertebral bodies cephalad and caudal to the metastasis. Multivariable logistic regression was used to identify predictors of post-SBRT pathological fracture. A total of 292 patients (mean age 66 years) with 392 unique lesions were included. The most common pathologies were prostate (n = 193), kidney/renal cell (n = 46), and lung (n = 33). The most common tumor levels were thoracic (n = 206 lesions) and lumbar (n = 128 lesions). SBRT was generally delivered in 1-3 fractions with doses ranging from 16 to 24 Gy in 1 fraction and 24-36 Gy in 3 fractions. Of the 392 lesions, 73 suffered VCF: 21 (29%) with < 25% height loss, 15 (21%) with 25%-40% height loss, and 37 (51%) with > 40% height loss. On univariate analysis, patients with VCF had lower average HUs (156 ± 52 vs 202 ± 89, p < 0.001), more WBB sectors involved (3 ± 2 vs 3 ± 1, p < 0.001), higher SINSs (8 ± 3 vs 6 ± 2, p < 0.001), were more commonly female (33% vs 22%, p = 0.05), and more commonly had nonprostate pathology (67% vs 47%, p = 0.003). VCF rates were similar between moderate (< 20 Gy in 1 fraction, < 30 Gy in 3 or 5 fractions) and high-dose (> 20 Gy in 1 fraction, > 30 Gy in 3 or 5 fractions) radiation schema (15% VCF vs 16% no VCF, respectively; p = 0.99). On multivariable logistic regression, independently significant predictors of VCF were HUs ≤ 229 (OR 6, p < 0.001), affected levels ≥ 3 WBB segments (OR 3, p < 0.001), and an SINS ≥ 8 (OR 2, p = 0.02). Low pre-radiation HUs, involvement of more WBB sectors, and a higher SINS were independent predictors of VCF following SBRT for metastatic spine disease.

Study designRetrospective cohort study.ObjectivesThis study evaluated the outcomes of radiation therapy (RT) as the initial treatment for Bilsky grade 2 metastatic epidural spinal cord compression (MESCC) and identified the risk factors associated with RT failure.MethodsThis retrospective cohort study enrolled 151 patients diagnosed with Bilsky grade 2 MESCC. Patients were divided into 2 groups, viz. those who initially underwent RT (n = 127) and those treated with surgery at presentation (n = 24). The patient demographics, treatment outcomes, and risk factors for RT failure were analyzed. The Spinal Instability Neoplastic Score (SINS) and clinical outcomes such as ambulatory status and neurological function were compared. Logistic regression was performed to identify factors predictive of RT failure.ResultsRT was successful in 85.8% (109/127) of patients, and only 14.2% (18/127) required surgery due to symptom progression. The SINS were significantly higher in the RT-failure group (9.6 ± 3.2) than in the RT-success group (7.4 ± 2.8, P = 0.003). SINS scores >8 were associated with a higher risk of RT failure. Patients the surgery group were younger and presented more frequently with neurological deficits. No significant differences in final ambulatory status or survival were observed between the RT-success and RT-failure subgroups.ConclusionsRT can be a viable initial treatment option for Bilsky grade 2 MESCC in the absence of neurological deficits or severe mechanical pain. However, patients with greater spinal instability (SINS >8) face a higher risk of RT failure and may benefit from surgical intervention at diagnosis.

BackgroundSpine stereotactic body radiation therapy (SBRT) for the treatment of metastatic disease is increasingly utilized owing to improved pain and local control over conventional regimens. Vertebral body collapse (VBC) is an important toxicity following spine SBRT. We investigated our institutional experience with spine SBRT as it relates to VBC and spinal instability neoplastic score (SINS).Patients and methodsRecords of 83 patients with 100 spinal lesions treated with SBRT between 2007 and 2022 were reviewed. Clinical information was abstracted from the medical record. The primary endpoint was post-treatment VBC. Logistic univariate analysis was performed to identify clinical factors associated with VBC.ResultsMedian dose and number of fractions used was 24 Gy and 3 fractions, respectively. There were 10 spine segments that developed VBC (10%) after spine SBRT. Median time to VBC was 2.4 months. Of the 11 spine segments that underwent kyphoplasty prior to SBRT, none developed subsequent VBC. No factors were associated with VBC on univariate analysis.ConclusionsThe rate of vertebral body collapse following spine SBRT is low. Prophylactic kyphoplasty may provide protection against VBC and should be considered for patients at high risk for fracture.

De novo spinal infections are an increasing medical problem. The decision-making for surgical or nonsurgical treatment for de novo spinal infections is often a non-evidence-based process and commonly a case-by-case decision by single physicians. A scoring system based on the latest evidence might help improve the decision-making process compared with other purely radiology-based scoring systems or the judgment of a single senior physician. Patients older than 18 years with an infection of the spine who underwent nonsurgical or surgical treatment between 2019 and 2021 were identified. Clinical data for neurological status, pain, and existing comorbidities were gathered and transferred to an anonymous spreadsheet. Patients without an MR image and a CT scan of the affected spine region were excluded from the investigation. A multidisciplinary expert panel used the Spine Instability Neoplastic Score (SINS), Spinal Instability Spondylodiscitis Score (SISS), and Spinal Infection Treatment Evaluation Score (SITE Score), previously developed by the authors' group, on every clinical case. Each physician of the expert panel gave an individual treatment recommendation for surgical or nonsurgical treatment for each patient. Treatment recommendations formed the expert panel opinion, which was used to calculate predictive validities for each score. A total of 263 patients with spinal infections were identified. After the exclusion of doubled patients, patients without de novo infections, or those without CT and MRI scans, 123 patients remained for the investigation. Overall, 70.70% of patients were treated surgically and 29.30% were treated nonoperatively. Intraclass correlation coefficients (ICCs) for the SITE Score, SINS, and SISS were 0.94 (95% CI 0.91-0.95, p < 0.01), 0.65 (95% CI 0.91-0.83, p < 0.01), and 0.80 (95% CI 0.91-0.89, p < 0.01). In comparison with the expert panel decision, the SITE Score reached a sensitivity of 96.97% and a specificity of 81.90% for all included patients. For potentially unstable and unstable lesions, the SISS and the SINS yielded sensitivities of 84.42% and 64.07%, respectively, and specificities of 31.16% and 56.52%, respectively. The SITE Score showed higher overall sensitivity with 97.53% and a higher specificity for patients with epidural abscesses (75.00%) compared with potentially unstable and unstable lesions for the SINS and the SISS. The SITE Score showed a significantly higher agreement for the definitive treatment decision regarding the expert panel decision, compared with the decision by a single physician for patients with spondylodiscitis, discitis, or spinal osteomyelitis. The SITE Score shows high sensitivity and specificity regarding the treatment recommendation by a multidisciplinary expert panel. The SITE Score shows higher predictive validity compared with radiology-based scoring systems or a single physician and demonstrates a high validity for patients with epidural abscesses.

Background ContextConventional external beam radiation therapy (cEBRT) is used in multiple myeloma (MM) to treat severe pain, spinal cord compression, and disease-related bone disease. However, radiation may be associated with an increased risk of vertebral compression fractures (VCFs), which could substantially impair survival and quality of life. Additionally, the use of the Spinal Instability Neoplastic Score (SINS) in MM is debated in MM. PurposeTo determine the incidence of VCFs after cEBRT in patients with MM and to assess the applicability of the SINS score in the prediction of VCFs in MM. Study DesignRetrospective multicenter cohort study. Patient SampleMM patients with spinal myeloma lesions who underwent cEBRT between January 2010 and December 2021. Outcome MeasuresFrequency of new or progressed VCFs and subdistribution hazard ratios for potentially associated factors. MethodsPatient and treatment characteristics were manually collected from the patients’ electronic medical records. Computed tomography (CT) scans from before and up to 3 years after the start of radiation were used to score radiographic variables at baseline and at follow-up. Multivariable Fine and Gray competing risk analyses were performed to evaluate the diagnostic value of the SINS score to predict the postradiation VCF rate. ResultsA total of 127 patients with 427 eligible radiated vertebrae were included in this study. The mean age at radiation was 64 years, and 66.1% of them were male. At the start of radiation, 57 patients (44.9%) had at least one VCF. There were 89 preexisting VCFs (18.4% of 483 vertebrae). Overall, 39 of 127 patients (30.7%) reported new fractures (number of vertebrae (n)=12) or showed progression of existing fractures (n=36). This number represented 11.2% of all radiated vertebrae. Five of the 39 (12.8%) patients with new or worsened VCFs received an unplanned secondary treatment (augmentation [n=2] or open surgery [n=3]) within 3 years. Both the total SINS score (SHR 1.77; 95% confidence interval (CI) 1.54–2.03; p<.001) and categorical SINS score (SHR 10.83; 95% CI 4.20–27.94; p<.001) showed an independent association with higher rates of new or progressed VCFs in adjusted analyses. The use of bisphosphonates was independently associated with a lower rate of new or progressed VCFs (SHR 0.47 [95% CI 0.24–0.92; p=.027]). ConclusionsThis study demonstrated that new or progressed VCFs occurred in 30.7% of patients within 3 years, in a total of 11.2% of vertebrae. The SINS score was found to be independently associated with the development or progression of VCFs and could thus be applied in MM for fracture prediction and possibly prevention.