Anne L. Versteeg

Reliability of the spinal instability neoplastic scale among radiologists: an assessment of instability secondary to spinal metastases.

OBJECTIVE The spinal instability neoplastic scale (SINS) is a new classification system for tumor-related spinal instability. The SINS may prove to be a valuable tool for radiologists to communicate with oncologists and surgeons in a standardized evidence-based manner. The objective of this study was to determine the inter- and intraobserver reliability and validity of the SINS among radiologists. MATERIALS AND METHODS Thirty-seven radiologists from 10 international sites used the SINS to categorize the degree of spinal instability in 30 patients with spinal tumors. To assess validity, we compared the SINS scores assigned by the radiologists with the SINS scores of 11 spine oncology surgeons (reference standard). Each total SINS score (range, 0-18 points) was converted into one of the following three clinical categories: 0-6 points, stable; 7-12 points, potentially unstable; and 13-18 points, unstable. In addition, each total SINS score was converted into a binary scale: 0-6 points was defined as stable, and 7-18 points was considered a current or possible instability for which surgical consultation is recommended. RESULTS Radiologists using the SINS binary scale showed excellent (κ = 0.88) validity, substantial (κ = 0.76) interobserver agreement, and excellent (κ = 0.82) intraobserver reproducibility. Radiologists rated all unstable cases and 621 of 629 (98.7%) potentially unstable cases with a SINS score of 7 or more points, thus appropriately initiating a referral for surgical assessment. CONCLUSION SINS is a reliable tool for radiologists rating tumor-related spinal instability. It accurately discriminates between stable and potentially unstable or unstable lesions and, therefore, can guide the need for surgical consultation.

Surgical Management of Spinal Chondrosarcomas

Study Design. An ambispective cohort study. Objective. The aim of this study was to determine whether the application of the Enneking classification in the management of spinal chondrosarcomas influences local recurrence and survival. Summary of Background Data. Primary spinal chondrosarcomas are rare. Best available evidence is based on small case series, thus making it difficult to determine optimal management and risk factors for local recurrence and survival. Methods. The AOSpine Knowledge Forum Tumor developed a multicenter ambispective database of surgically treated patients with spinal chondrosarcoma. Patient data pertaining to demographics, diagnosis, treatment, cross-sectional survival, and local recurrence were collected. Tumors were classified according to the Enneking classification. Patients were divided into two cohorts: Enneking appropriate (EA) and Enneking inappropriate (EI). They were categorized as EA when the final pathological assessment of the margin matched the Enneking recommendation, and otherwise, they were categorized as EI. Results. Between 1987 and 2011, 111 patients (37 female; 74 male) received surgical treatment for a primary spinal chondrosarcoma at a mean age of 47.4 ± 15.8 years. Patients were followed for a median period of 3.1 years (range = 203 d–18.7 yrs). Median survival for the entire cohort was 8.4 years postoperative. After 10 years postoperative, 36 (32%) patients died and 37 (35%) patients suffered a local recurrence. Twenty-three of these 37 patients who suffered a local recurrence died. Sixty (58%) patients received an EA procedure while 44 (42%) received an EI procedure. EI patients had a higher hazard ratio for local recurrence than those who received an EA procedure (P = 0.052). Local recurrence was strongly associated with chondrosarcoma-related death (risk ratio = 3.6, P < 0.010). Conclusion. This is the largest multicenter cohort of spinal chondrosarcomas. EA surgical management appeared to correlate with a decreased risk of local recurrence, yet no relationship with survival was found. Where possible, surgeons should strive to achieve EA margins to minimize the risk of local recurrence. Level of Evidence: 4

The Spinal Instability Neoplastic Score: Impact on Oncologic Decision-Making.

Study Design. Systematic literature review. Objective. To address the following questions in a systematic literature review:  1. How is spinal neoplastic instability defined or classified in the literature before and after the introduction of the Spinal Instability Neoplastic Score (SINS)?  2. How has SINS affected daily clinical practice?  3. Can SINS be used as a prognostic tool? Summary of Background Data. Spinal neoplastic-related instability was defined in 2010 and simultaneously SINS was introduced as a novel tool with criteria agreed upon by expert consensus to assess the degree of spinal stability. Methods. PubMed, Embase, and clinical trial databases were searched with the key words “spinal neoplasm,” “spinal instability,” “spinal instability neoplastic score,” and synonyms. Studies describing spinal neoplastic-related instability were eligible for inclusion. Primary outcomes included studies describing and/or defining neoplastic-related instability, SINS, and studies using SINS as a prognostic factor. Results. The search identified 1414 articles, of which 51 met the inclusion criteria. No precise definition or validated assessment tool was used specific to spinal neoplastic-related instability prior to the introduction of SINS. Since the publication of SINS in 2010, the vast majority of the literature regarding spinal instability has used SINS to assess or describe instability. Twelve studies specifically investigated the prognostic value of SINS in patients who underwent radiotherapy or surgery. Conclusion. No consensus could be determined regarding the definition, assessment, or reporting of neoplastic-related instability before introduction of SINS. Defining spinal neoplastic-related instability and the introduction of SINS have led to improved uniform reporting within the spinal neoplastic literature. Currently, the prognostic value of SINS is controversial. Level of Evidence: N/A

The Effect of Introducing the Spinal Instability Neoplastic Score in Routine Clinical Practice for Patients With Spinal Metastases

BACKGROUND Stable spinal metastases are effectively treated with radiotherapy, whereas unstable spinal metastases often need surgical fixation followed by radiotherapy for local control. The Spinal Instability Neoplastic Score (SINS) was developed as a tool to assess spinal neoplastic related instability with the goal of helping to guide referrals among oncology specialists. We compare the average degree of spinal instability between patients with spinal metastases referred for surgery or for radiotherapy and evaluate whether this difference changed after introduction of the SINS in clinical practice. METHODS All patients with spinal metastases treated with palliative surgery or radiotherapy in the period 2009-2013 were identified in two spine centers. For all patients, the SINS was scored on pretreatment imaging. The SINS before and after introduction of the SINS in 2011 were compared within the surgical and radiotherapy group. Furthermore, the overall SINS was compared between the two groups. RESULTS The overall SINS was significantly higher in the surgical group, with a mean SINS of 10.7 (median 11) versus 7.2 (median 8) for the radiotherapy group. The mean SINS decreased significantly for both groups after introduction of the SINS in clinical practice from 11.2 to 10.3 in the surgical group and from 8.4 to 7.2 in the radiotherapy group. CONCLUSION The SINS differed significantly between patients treated with surgery or radiotherapy. The introduction of SINS led to a decrease in SINS score for both groups, suggesting that using SINS in metastatic spinal disease increases awareness for instability and may subsequently result in earlier referrals for surgical intervention. IMPLICATIONS FOR PRACTICE Spinal metastases can present with varying degrees of mechanical instability. Because unstable spinal metastases may respond insufficiently to palliative radiotherapy and can lead to loss of ambulation, timely detection and appropriate referral are important. The Spinal Instability Neoplastic Score (SINS) may help physicians caring for patients with metastasized disease to identify spinal instability before the onset of neurological deficits. In this study, it was shown that the introduction of SINS in routine practice led to a decrease in spinal instability in radiotherapy and surgical cohorts. The use of SINS may increase awareness of instability and subsequently result in earlier referrals.

Characteristics of Patients Who Survived 2 Years After Surgery for Spinal Metastases: Can We Avoid Inappropriate Patient Selection?

PURPOSE Survival after metastatic cancer has improved at the cost of increased presentation with metastatic spinal disease. For patients with pathologic spinal fractures and/or spinal cord compression, surgical intervention may relieve pain and improve quality of life. Surgery is generally considered to be inappropriate if anticipated survival is < 3 months. The aim of this international multicenter study was to analyze data from patients who died within 3 months or 2 years after surgery, to identify preoperative factors associated with poor or good survival, and to avoid inappropriate selection of patients for surgery in the future. PATIENTS AND METHODS A total of 1,266 patients underwent surgery for impending pathologic fractures and/or neurologic deficits and were prospectively observed. Data collected included tumor characteristics, preoperative fitness (American Society of Anesthesiologists advisory [ASA]), neurologic status (Frankel scale), performance (Karnofsky performance score [KPS]), and quality of life (EuroQol five-dimensions questionnaire [EQ-5D]). Outcomes were survival at 3 months and 2 years postsurgery. Univariable and multivariable logistic regression analyses were used to find preoperative factors associated with short-term and long-term survival. RESULTS In univariable analysis, age, emergency surgery, KPS, EQ-5D, ASA, Frankel, and Tokuhashi/Tomita scores were significantly associated with short survival. In multivariable analysis, KPS and age were significantly associated with short survival (odds ratio [OR], 1.36; 95% CI, 1.15 to 1.62; and OR, 1.14; 95% CI, 1.02 to 1.27, respectively). Associated with longer survival in univariable analysis were age, number of levels included in surgery, KPS, EQ-5D, Frankel, and Tokuhashi/Tomita scores. In multivariable analysis, the number of levels included in surgery (OR, 1.21; 95% CI, 1.06 to 1.38) and primary tumor type were significantly associated with longer survival. CONCLUSION Poor performance status at presentation is the strongest indicator of poor short-term survival, whereas low disease load and favorable tumor histology are associated with longer-term survival.

Prospective Evaluation of the Relationship Between Mechanical Stability and Response to Palliative Radiotherapy for Symptomatic Spinal Metastases

BACKGROUND A substantial number of patients with spinal metastases experience no treatment effect from palliative radiotherapy. Mechanical spinal instability, due to metastatic disease, could be associated with failed pain control following radiotherapy. This study investigates the relationship between the degree of spinal instability, as defined by the Spinal Instability Neoplastic Score (SINS), and response to radiotherapy in patients with symptomatic spinal metastases in a multi-institutional cohort. METHODS AND MATERIALS The SINS of 155 patients with painful thoracic, lumbar, or lumbosacral metastases from two tertiary hospitals was calculated using images from radiotherapy planning CT scans. Patient-reported pain response, available for 124 patients, was prospectively assessed. Pain response was categorized, according to international guidelines, as complete, partial, indeterminate, or progression of pain. The association between SINS and pain response was estimated by multivariable logistic regression analysis, correcting for predetermined clinical variables. RESULTS Of the 124 patients, 16 patients experienced a complete response and 65 patients experienced a partial response. Spinal Instability Neoplastic Score was associated with a complete pain response (adjusted odds-radio [ORadj] 0.78; 95% confidence interval [CI] 0.62-0.98), but not with an overall pain response (ORadj 0.94; 95% CI 0.81-1.10). CONCLUSIONS A lower SINS, indicating spinal stability, is associated with a complete pain response to radiotherapy. This supports the hypothesis that pain resulting from mechanical spinal instability responds less well to radiotherapy compared with pain from local tumor activity. No association could be determined between SINS and an overall pain response, which might indicate that this referral tool is not yet optimal for prediction of treatment outcome. IMPLICATIONS FOR PRACTICE Patients with stable painful spinal metastases, as indicated by a Spinal Instability Neoplastic Score (SINS) of 6 or lower, can effectively be treated with palliative external beam radiotherapy. The majority of patients with (impending) spinal instability, as indicated by a SINS score of 7 or higher, will achieve a (partial) response after palliative radiotherapy; however, some patients might require surgical intervention. Therefore, it is recommended to refer patients with a SINS score of 7 or higher to a spine surgeon to evaluate the need for surgical intervention.

Surgical management of spinal osteoblastomas

OBJECTIVE Osteoblastoma is a rare primary benign bone tumor with a predilection for the spinal column. Although of benign origin, osteoblastomas tend to behave more aggressively clinically than other benign tumors. Because of the low incidence of osteoblastomas, evidence-based treatment guidelines and high-quality research are lacking, which has resulted in inconsistent treatment. The goal of this study was to determine whether application of the Enneking classification in the management of spinal osteoblastomas influences local recurrence and survival time. METHODS A multicenter database of patients who underwent surgical intervention for spinal osteoblastoma was developed by the AOSpine Knowledge Forum Tumor. Patient data pertaining to demographics, diagnosis, treatment, cross-sectional survival, and local recurrence were collected. Patients in 2 cohorts, based on the Enneking classification of the tumor (Enneking appropriate [EA] and Enneking inappropriate [EI]), were analyzed. If the final pathology margin matched the Enneking-recommended surgical margin, the tumor was classified as EA; if not, it was classified as EI. RESULTS A total of 102 patients diagnosed with a spinal osteoblastoma were identified between November 1991 and June 2012. Twenty-nine patients were omitted from the analysis because of short follow-up time, incomplete survival data, or invalid staging, which left 73 patients for the final analysis. Thirteen (18%) patients suffered a local recurrence, and 6 (8%) patients died during the study period. Local recurrence was strongly associated with mortality (relative risk 9.2; p = 0.008). When adjusted for Enneking appropriateness, this result was not altered significantly. No significant differences were found between the EA and EI groups in regard to local recurrence and mortality. CONCLUSIONS In this evaluation of the largest multicenter cohort of spinal osteoblastomas, local recurrence was found to be strongly associated with mortality. Application of the Enneking classification as a treatment guide for preventing local recurrence was not validated.

Psychometric evaluation and adaptation of the Spine Oncology Study Group Outcomes Questionnaire to evaluate health-related quality of life in patients with spinal metastases

The Spine Oncology Study Group Outcomes Questionnaire (SOSGOQ) was developed as the first spine oncology‐specific health‐related quality of life (HRQOL) measure. This study evaluated the psychometric properties and clinical validity of the SOSGOQ in a diverse cohort of patients with spinal metastases.

Surgical Management of Spinal Osteoblastomas

Introduction Primary spinal osteoblastomas are rare benign neoplasms which often behave more aggressively than other benign tumors and can present as malignant transformations. Optimal surgical treatment strategies and risk factors for local recurrence and mortality of spinal osteoblastomas remain unclear. The aim of this multicenter cohort study was to assess rates of local recurrence and mortality following surgical intervention for spinal osteoblastomas and to evaluate whether the application of the Enneking classification in the management of these tumors influences local recurrence and mortality. Methods The AOSpine Knowledge Forum Tumor developed a multicenter ambispective database of patients who underwent surgical intervention for spinal osteoblastoma. Patient demographic, diagnosis, treatment, cross-sectional survival, and local recurrence data were collected. Patients were analyzed in two cohorts based on the Enneking classification of the tumor: Enneking appropriate (EA) and Enneking inappropriate (EI). EA was defined by the final pathology margin matching the Enneking recommended surgical margin, if otherwise, it was defined as EI. Results Between November 1991 and June 2012, a total of 102 patients diagnosed with a spinal osteoblastoma were identified. Twenty-eight patients were omitted from the analysis due to insufficient follow-up (<12 months) or incomplete survival data, leaving 74 patients for final analysis. The mean follow-up was 4.3 ± 2.8 years in the EI and 4.5 ± 3.3 years in the EA group. Thirteen (18%) patients suffered a local recurrence and six (8%) patients died during the study period. Local recurrence was strongly associated with mortality with a relative risk of 9.4 (p = 0.007). When adjusting for Enneking appropriateness, the result was not significantly altered. Significant differences were not found between the EA and EI groups for local recurrence and mortality. Conclusion Upon evaluating the largest multicenter cohort of spinal osteoblastomas to date, the application of the Enneking classification as treatment guide for spinal osteoblastomas could not be confirmed. Considering the consequences of a local recurrence and the strong association of local recurrence with mortality even after adjusting for Enneking appropriateness, en bloc or marginal resection is nevertheless the recommended surgical treatment strategy for spinal osteoblastoma.