Is the Spinal Instability Neoplastic Score Accurate and Reliable in Predicting Vertebral Compression Fractures for Spinal Metastasis? A Systematic Review and Qualitative Analysis

Lee, Chang-Hyun,Hong, Jae Taek,Lee, Sun-Ho,Yi, Seong,Sohn, Moon-Jun,Kim, Sung Hwan,Chung, Chun Kee,Korean Spine Oncology Research Society The Korean Neurosurgical Society 2021 Journal of Korean neurosurgical society Vol.64 No.1

Spinal metastases can present with varying degrees of mechanical instability. The Spinal Instability Neoplastic Score (SINS) was developed as a tool to assess spinal neoplastic-related instability while helping to guide referrals among oncology specialists. Some previous papers suggested that the SINS was accurate and reliable, while others disagreed with this opinion. We performed a systematic review regarding the SINS to evaluate its accuracy and precision in predicting vertebral compression fractures (VCFs). The 21 included studies investigated a total of 2118 patients. Thirteen studies dealt with the accuracy of SINS to predict post-radiotherapy VCFs, and eight dealt with the precision. Among 13 studies, 11 agreed that the SINS categories showed statistically significant accuracy in predicting VCF. Among eight studies, body collapse was effective for predicting VCFs in six studies, and alignment and bone lesion in two studies. Location has no statistical significance in predicting VCFs in any of the eight studies. The precision of SINS categories was substantial to excellent in six of eight studies. Among the six components of the SINS, the majority of the included studies reported that location showed near perfect agreement; body collapse, alignment, and posterolateral involvement showed moderate agreement; and bone lesion showed fair agreement. Bone lesion showed significant accuracy in predicting VCFs in half of eight studies, but displayed fair reliability in five of seven studies. Although location was indicated as having near perfect reliability, the component showed no accuracy for predicting VCFs in any of the studies and deleting or modifying the item needs to be considered. The SINS system may be accurate and reliable in predicting the occurrence of post-radiotherapy VCFs for spinal metastasis. Some components seem to be substantially weak and need to be revised.

Outcomes and Prognosis of Neurological Decompression and Stabilization for Spinal Metastasis: Is Assessment with the Spinal Instability Neoplastic Score Useful for Predicting Surgical Results?

Kenji Masuda,Ko Ebata,Yoshimasa Yasuhara,Akira Enomoto,Tomoyuki Saito 대한척추외과학회 2018 Asian Spine Journal Vol.12 No.5

Study Design: Retrospective study. Purpose: To evaluate the efficacy of the Spinal Instability Neoplastic Score (SINS) in predicting surgical outcomes and survival. Patients were categorized into two groups according to the SINS, and their surgical outcomes and survival following decompression and stabilization were assessed. Overview of Literature: Palliative surgery in patients with a life expectancy ≥3 months may effectively improve their overall condition in the long term. Currently, the effectiveness of the SINS for predicting surgical results and survival remains controversial. Methods: This study included 44 patients who underwent decompression and stabilization for spinal metastases at Yokosuka Kyosai Hospital between 2008 and 2017. The patients were divided into two groups: stable (SINS ≤12) and unstable (SINS ≥13). Changes in the Frankel score and Eastern Cooperative Oncology Group Performance Status (ECOG-PS) were compared between the two groups, and patient survival was evaluated according to the SINS, Tokuhashi score, and Katagiri score. Results: The stable group (SINS range, 7–12) included 24 patients while the unstable group (SINS range, 13–16) included 20 patients. The Frankel score significantly improved from 2.8 to 3.6 in the stable group (p <0.001) and from 2.7 to 3.9 in the unstable group (p <0.001). The ECOG-PS significantly improved from 3.2 to 2.1 in the stable group (p <0.001) and from 3.0 to 1.8 in the unstable group (p <0.001). There was a statistically significant difference in median survival between the two groups. Conclusions: All patients treated with palliative surgery showed favorable outcomes, as indicated by improved the Frankel score and ECOG-PS following surgery. However, median survival was significantly better in the stable group. The results of this study indicate that the SINS is appropriate for surgical decision making and may be used to predict survival.

척추 전이 종양 환자의 수술 방법 결정에 있어 Spinal Instability Neoplastic Score (SINS)의 의의

박상민,김형민,하재홍,이석중,김호중,염진섭,이춘기,장봉순 대한척추외과학회 2018 대한척추외과학회지 Vol.25 No.2

Study Design: Retrospective cohort study. Objectives: To investigate the potential clinical use of the spinal instability neoplastic score (SINS) for determining the surgical strategy, especially regarding the need for anterior support. Summary of Literature Review: The SINS seems to enable an improved qualitative and quantitative assessment of spinal instability in patients with spinal metastasis. Materials and Methods: We retrospectively reviewed 69 consecutive patients who underwent surgical treatment for spinal metastasis. We assessed the patients’ preoperative status with respect to each component of the SINS. Multiple logistic regression was performed to calculate odds ratios (ORs) representing the associations among SINS, age, Eastern Cooperative Oncology Group performance status, modified Tokuhashi score, as well as the preoperative Nurick grade variables and reconstruction of the anterior spinal column. Results: Among the 6 items in the SINS, those indicating the degree of collapse and alignment had significantly higher scores in those who underwent corpectomy and anterior support (p<0.001). Multiple logistic regression revealed that the total SINS was the only factor significantly associated with predicting whether anterior support should be performed (adjusted OR=1.595). Receiver operating characteristic (ROC) curve analysis suggested that a cut-off value of 10 points on the SINS scale could be used to decide whether anterior support following corpectomy should be performed (AUC=0.706). Conclusions: The SINS, insofar as it assesses the degree of collapse and alignment, is a potentially useful tool for determining the surgical strategy in patients with spinal metastasis, especially for deciding upon the necessity of additional anterior support procedures. 연구 계획: 후향적 코호트 연구목적: Spinal Instability Neoplastic Score (SINS)이 기존에 알려져 있는 척추 전이 종양 환자들의 수술 방법의 결정에 어떤 역할을 하는지 평가하고자 한다. 선행 연구문헌의 요약: SINS는 척추 전이 종양에서 척추 불안정성을 평가하는 방법이다. 대상 및 방법: 척추 전이 종양으로 수술 받은 총 69명 환자들에 대해 수술 전 SINS 구성 요소를 후향적으로 평가하였다. 로지스틱 회귀분석을 이용하여SINS 구성요소, 각종 환자 정보 및 전방 지지술 유무와의 연관성을 살펴보았다. 결과: SINS의 항목 중 추체의 함몰 정도(p<0.001)와 척추 정렬 상태(p=0.001)가 추체 제거 정도 및 전방지지술 유무와 유의한 관계가 있었다. 로지스틱회귀분석에서 SINS의 총 점수가 전방 지지술 유무와 유의한 관계가 있었다(adjusted OR=1.595). ROC 곡선을 이용한 분석에서 SINS 10점을 추체 제거술 및 전방지지술을 시행하는 절단 값으로 정하였고, 값은 0.704였다. 결론: SINS 점수 중 추체 함몰 정도와 척추 정렬상태는 척추 종양 환자의 수술 결정에 대해 유용한 수술 결정 방법이며, 특히 전방지지술의 시행여부를결정하는 중요한 요소이다. 약칭 제목: SINS를 이용한 수술방법결정

Prognosis of Single Spinal Metastatic Tumors: Predictive Value of the Spinal Instability Neoplastic Score System for Spinal Adverse Events

Hyoungmin Kim,장삼열,Jae Hong Ha,서상교,Bong-Soon Chang,Choon-Ki Lee 대한척추외과학회 2018 Asian Spine Journal Vol.12 No.5

Study Design: This was a retrospective cohort study. Purpose: We evaluated the predictive value of the Spinal Instability Neoplastic Score (SINS) system for spinal adverse events (SAEs) in patients with single spinal metastatic tumor. Overview of Literature: The SINS system was developed to assess spinal instability in patients with single metastatic spinal tumor. However, the system’s potential predictive value for SAEs has been partially studied. Methods: This system was applied to a retrospective cohort of 78 patients with single spinal metastatic tumors. The patients underwent surgical treatment and were postoperatively followed up for at least 2 years or until death. The attribution of each score and total SINS to SAE (vertebral compression fracture [VCF] and spinal cord compression [SCC]) occurrence was assessed using the Cox proportional hazards model. Results: SAEs occurred on average 7 months after diagnosis of spinal metastasis. The mean survival rate post diagnosis was 43 months. Multivariate analysis using the Cox proportional hazards model revealed that the pain (p =0.029) and spinal alignment (p =0.001) scores were significantly related to VCF occurrence, whereas the pain (p =0.008) and posterolateral involvement (p =0.009) scores were related to SCC occurrence. Conclusions: Among the components of the SINS system, while pain and spinal alignment showed a significant association with VCF occurrence, pain and posterolateral involvement showed association with SCC occurrence.

Treatment Strategy for Impending Instability in Spinal Metastases

Yeon Ho Kim,Junho Kim,Sam Yeol Chang,Hyoungmin Kim,Bong-Soon Chang 대한정형외과학회 2020 Clinics in Orthopedic Surgery Vol.12 No.3

Background: Determining surgical management of a spinal metastasis is difficult owing to the involvement of multiple factors. The spinal instability neoplastic score (SINS) system is a reliable tool to evaluate instability in spinal metastases. The intermediate SINS (scores 7–12) indicates impending instability, which makes it difficult to determine the proper treatment strategy. In this study, we aimed to compare the initial status and treatment outcomes of a conservative group versus an operative group among patients with spinal metastases with an intermediate SINS of 7–12. Further, we evaluated the time for conversion to surgery in patients who had initially undergone conservative treatment and identified the factors associated with the conversion. Methods: Among the patients with a spinal metastasis with an intermediate SINS of 7–12 from May 2013 to December 2017, those who were followed up for more than 12 months were enrolled in this study. Patients with signs of a neurologic deficit or cord compression at the initial diagnosis were excluded. Finally, 79 patients (47 in the initially conservative group and 32 in the initially operative group) were enrolled in this study. The performance status, Tomita score, and Tokuhashi score were assessed for group comparison. Components of SINS, the Bilsky grade, and radiosensitivity of tumor were evaluated to determine factors associated with conversion to surgery. Results: Average follow-up was 20.9 months (range, 12–46 months). The demographic variables, primary cancer type, and performance status were not significantly different between the 2 groups. However, the Tomita score was lower in the initially operative group (p = 0.006). The 1-year treatment outcome assessed based on the change in performance status and vertebral height collapse showed a tendency to deteriorate less in the initially operative group. The rate of conversion to surgery in the initially conservative group was 33% in the first year, after which there was little change in the incidence of conversion. When vertebral body collapse was less than 50% or the tumor was located in the semi-rigid region (T3–T10), the need for conversion to surgery increased statistically significantly (p = 0.039 and p = 0.042, respectively). Conclusions: The rate of conversion to surgery in initially conservatively treated patients was about 33% in the first year. When a tumor is located in T3–T10 and less than 50% vertebral body collapse is present, surgery may be the better choice than conservative treatment.