Faculty Bibliography

BACKGROUND:Metastatic spine tumor surgery consists of palliative operations performed on frail patients with multiple medical comorbidities. Enhanced recovery after surgery (ERAS) programs involve an evidence-based, multidisciplinary approach to improve perioperative outcomes. This study presents clinical outcomes of a metastatic spine tumor ERAS pathway implemented at a tertiary cancer center. METHODS:The metastatic spine tumor ERAS program launched in April 2019, and data from January 2018 to May 2020 were reviewed. Measured outcomes included the following: hospital length of stay (LOS), time to ambulation, urinary catheter duration, time to resumption of diet, intraoperative fluid intake, estimated blood loss (EBL), and intraoperative and postoperative day 0-5 cumulative opioid use (morphine milligram equivalent [MME]). RESULTS:A total of 390 patients were included in the final analysis: 177 consecutive patients undergoing metastatic spine tumor surgery enrolled in the ERAS program and 213 consecutive pre-ERAS patients. Although the mean case durations were similar in the ERAS and pre-ERAS cohorts (265 vs. 274 min; p = .22), the ERAS cohort had decreased EBL (157 vs. 215 ml; p = .003), decreased postoperative day 0-5 cumulative mean opioid use (178 vs. 396 MME; p < .0001), earlier ambulation (mean, 34 vs. 57 h; p = .0001), earlier discontinuation of urinary catheters (mean, 36 vs. 56 h; p < .001), and shorter LOS (5.4 vs. 7.5 days; p < .0001). CONCLUSIONS:The implementation of a multidisciplinary ERAS program designed for metastatic spine tumor surgery led to improved clinical quality metrics, including shorter hospitalizations and significant reductions in opioid consumption.

Introduction: The objective of this analysis was to compare sociodemographic characteristics and outcomes between cohorts of patients receiving separation surgery for spinal metastases at two neighboring institutions, one private and one public, affiliated with a major academic medical center in a large metropolitan area.
Method(s): Patients who received separation surgery for spinal metastases between 2013 and 2021 were included in this analysis. Sociodemographic factors, treatment characteristics, and outcomes were compared between those treated at a private hospital and those treated at a neighboring public hospital using Rao-Scott chi square tests.
Result(s): Compared to those treated at our private hospital, patients treated at our public hospital were more often younger (p=0.005), of Black or Hispanic race (70% vs. 14.9%, p<0.001), and insured via Medicaid or Emergency Medicaid (48.6% vs. 3.2%, p<0.001). They more frequently presented with ESCC grade 3 compression (81.6% vs. 49.2%), potentially unstable or unstable lesions as denoted by SINS >7 (64.1% vs. 37.7%), and increased neurologic impairment as denoted by ASIA Impairment Scale scores of A, B, or C (35% vs. 7.9%). Local progression was less frequently observed in patients treated at our public hospital (28.2% vs. 54.7%, p=0.001), although this is likely due to poorer clinical and radiographic follow-up amongst this cohort. Median survival was significantly lower in patients treated at our public hospital (Median [Range]: 81 [11-1,873] days vs. 264 [0-3,092] days, p<0.001), although this is also likely confounded by lower rates of follow-up.
Conclusion(s): This study highlights substantial disparities amongst patients treated for spinal metastases at neighboring institutions affiliated with a major academic medical center. Further work is needed to identify reasons for these disparities and create avenues by which to mitigate them

Systemic assessment is a pillar in the neurological, oncological, mechanical, and systemic (NOMS) decision-making framework for the treatment of patients with spinal metastatic disease. Despite this importance, emerging evidence relating systemic considerations to clinical outcomes following surgery for spinal metastatic disease has not been comprehensively summarised. We aimed to conduct a scoping literature review of this broad topic. We searched MEDLINE, Embase, Scopus, Cochrane Central Register of Controlled Trials, Web of Science, and CINAHL databases from Jan 1, 2000, to July 31, 2021. 61 articles were included, accounting for a total of 22 335 patients. Preoperative systemic variables negatively associated with postoperative clinical outcomes included demographics (eg, older age [>60 years], Black race, male sex, low or elevated body-mass index, and smoking status), medical comorbidities (eg, cardiac, pulmonary, hepatic, renal, endocrine, vascular, and rheumatological), biochemical abnormalities (eg, hypoalbuminaemia, atypical blood cell counts, and elevated C-reactive protein concentration), low muscle mass, generalised motor weakness (American Spinal Cord Injury Association Impairment Scale grade and Frankel grade) and poor ambulation, reduced performance status, and systemic disease burden. This is the first comprehensive scoping review to broadly summarise emerging evidence relevant to the systemic assessment component of the widely used NOMS framework for spinal metastatic disease decision making. Medical, surgical, and radiation oncologists can consider these findings when prognosticating spinal metastatic disease-related surgical outcomes on the basis of patients' systemic condition. These factors might inform a shared decision-making approach with patients and their families.

BACKGROUND CONTEXT/BACKGROUND:Historically, spine surgeons used expected postoperative survival of 3-months to help select candidates for operative intervention in spinal metastasis. However, this cutoff has been challenged by the development of minimally invasive techniques, novel biologics, and advanced radiotherapy. Recent studies have suggested that life expectancy of 6 weeks may be enough to achieve significant improvements in postoperative health-related quality of life. PURPOSE/OBJECTIVE:The purpose of this study was to develop a model capable of predicting 6-week mortality in patients with spinal metastases treated with radiation or surgery. STUDY DESIGN/SETTING/METHODS:Retrospective review was conducted at five large tertiary centers in the United States and Taiwan. PATIENT SAMPLE/METHODS:The development cohort consisted of 3,001 patients undergoing radiotherapy and/or surgery for spinal metastases from one institution. The validation institutional cohort consisted of 1,303 patients from four independent, external institutions. OUTCOME MEASURES/METHODS:The primary outcome was six-week mortality METHODS: Five models were considered to predict six-week mortality, and the model with the best performance across discrimination, calibration, decision-curve analysis, and overall performance was integrated into an open access web-based application. RESULTS:The most important variables for prediction of 6-week mortality were albumin, primary tumor histology, absolute lymphocyte, three or more spine metastasis, and ECOG score. The elastic-net penalized logistic model was chosen as the best performing model with AUC 0.84 on evaluation in the independent testing set. On external validation in the 1,303 patients from the four independent institutions, the model retained good discriminative ability with an area under the curve of 0.81. The model is available here: https://sorg-apps.shinyapps.io/spinemetssurvival/. CONCLUSIONS:While this study does not advocate for the use of 6-week life expectancy as a criteria for considering operative management, the algorithm developed and externally validated in this study may be helpful for preoperative planning, multidisciplinary management, and shared decision making in spinal metastasis patients with shorter life expectancy.

BACKGROUND:Central tendency analysis studies demonstrate that surgery provides pain relief in spinal metastatic tumors. However, they preclude patient-specific probability of treatment outcome. OBJECTIVE:To use responder analysis to study the variability of pain improvement. METHODS:In this single-center, retrospective analysis, 174 patients were studied. Logistic regression modeling was used to associate preoperative characteristics with rating the Brief Pain Inventory (BPI) worst pain item 0 to 4. Linear regression modeling was used to associate preoperative characteristics with minimal clinically important improvement (MCI) in physical functioning defined by a 1-point decrease in the BPI Interference Construct score from preoperative baseline to 6 months postoperatively. RESULTS:Patient-level analysis revealed that 60% of patients experienced an improvement in pain. At least half experienced a decrease in pain resulting in MCI in physical functioning. Cutpoint analysis revealed that 48% were responders. Increasing scores on the preoperative pain intensity BPI items, the MD Anderson Symptom Inventory (MDASI) Core Symptom Severity Construct, the MDASI Spine Tumor-Specific Construct, the presence of preoperative neurologic deficits, and postoperative complications were associated with lower probability of treatment success while increasing severity in all BPI pain items, and MDASI constructs were associated with increased probability of MCI in physical function. Significant mortality and loss to follow-up intrinsic to this patient population limit the strength of these data. CONCLUSION/CONCLUSIONS:Although patients with milder preoperative symptoms are likely to achieve better pain relief after surgery, patients with worse preoperative symptom also benefit from surgery with adequate pain relief with an improvement in physical function.

PURPOSE/OBJECTIVE:The role of tumor genomic profiling is rapidly growing as it results in targeted, personalized, cancer therapy. Though routinely used in clinical practice, there are no data exploring the reliability of genomic data obtained from spine metastases samples often leading to multiple biopsies in clinical practice. This study compares the genomic tumor landscape between spinal metastases and the corresponding primary tumors as well as between spinal metastases and visceral metastases. PATIENTS AND METHODS/METHODS:Spine tumor samples, obtained for routine clinical care from 2013 to 2019, were analyzed using MSK-IMPACT, a next generation sequencing assay. These samples were matched to primary or metastatic tumors from the corresponding patients. A concordance rate for genomic alterations was calculated for matching sample pairs within patients for the primary and spinal metastatic tumor samples as well as for the matching sample pairs within patients for the spinal and visceral metastases. For a more robust and clinically relevant estimate of concordance, a subgroup analyses of previously established driver mutations specific to the main primary tumor histologies was performed. RESULTS:Eighty-four patients contributed next generation sequencing from a spinal metastasis and at least one other site of disease: 54 from the primary tumor, 39 had genomic tumor data from another, non-spinal metastasis, 12 patients participated in both subsets. For the cohort of matched primary tumors and spinal metastases (n = 54) comprised of mixed histologies, we found an average concordance rate of 96.97% for all genetic events, 97.17% for mutations, 100% for fusions, 89.81% for deletions, and 97.01% for amplifications across all matched samples. Notably, >25% of patients harbored at least one genetic variant between samples tested, though not specifically for known driver mutations. The average concordance rate of driver mutations was 96.99% for prostate cancer, 95.69% (p = 0.0004513) for lung cancer and 96.43% for breast cancer. An average concordance of 99.02% was calculated for all genetic events between spine metastases and non-spinal metastases (n=41) and, more specifically, a concordance rate of 98.91% was calculated between spine metastases and liver metastases (n=12) which was the largest represented group of non-spine metastases. CONCLUSION/CONCLUSIONS:Sequencing data performed on spine tumor samples demonstrate a high concordance rate for genetic alterations between the primary tumor and spinal metastasis as well as between spinal metastases and other, visceral metastases, particularly for driver mutations. Spine tumor samples may be reliably used for genomic based decision making in cancer care, particularly for prostate, NSCLC and breast cancer.

BACKGROUND:Historically, symptomatic, benign intradural extramedullary (IDEM) spine tumors have been managed with surgical resection. However, minimal robust data regarding patient-reported outcomes (PROs) following treatment of symptomatic lesions exists. Moreover, there are increasing reports of radiosurgical management of these lesions without robust health-related quality of life data. OBJECTIVE:To prospectively analyze PROs among patients with benign IDEM spine tumors undergoing surgical resection to define the symptomatic efficacy of surgery. METHODS:Prospective, single-center observational cohort study of patients with benign IDEM spine tumors undergoing open surgical resection. Pre- and postoperative Brief Pain Index (BPI) and MD Anderson Symptom Inventory (MDASI) questionnaires were used to quantitatively assess their symptom control after surgical intervention. Matched pairs were analyzed with the Wilcoxon signed-rank test. RESULTS:A total of 57 patients met inclusion criteria with both pre- and postoperative PROs. There were 35 schwannomas, 18 meningiomas, 2 neurofibromas, 1 paraganglioma, and 1 mixed schwannoma/neurofibroma. Most patients were American Spinal Injury Association Impairment (ASIA) E (93%) with high-grade spinal cord compression (77%), and underwent either a 2 or 3 level laminectomy (84%). Surgical resection resulted in statistically significant improvement in all 3 composite BPI constructs of pain-severity, pain-interference, and overall patient pain experience (P < .0001). Surgical resection resulted in statistically significant improvements in all composite scores for the MDASI core symptom severity, spine tumor, and disease interference constructs (P < .01). Three patients (5%) had postoperative complications requiring surgical interventions (2 wound revisions and 1 ventriculo-peritoneal shunt). CONCLUSION:Surgical resection of IDEM spine tumors provides rapid, significant, and durable improvement in PROs.

OBJECTIVE:High-grade metastatic epidural spinal cord compression from radioresistant tumor histologies is often treated with separation surgery and adjuvant stereotactic body radiation therapy. Historically, long-segment fixation is performed during separation surgery with posterior transpedicular fixation of a minimum of 2 spinal levels superior and inferior to the decompression. Previous experience with minimal access surgery techniques and percutaneous stabilization have highlighted reduced morbidity as an advantage to the use of shorter fixation constructs. Cement augmentation of pedicle screws is an attractive option for enhanced stabilization while performing shorter fixation. Herein, the authors describe their initial experience of open separation surgery using short-segment cement-augmented pedicle screw fixation for spinal reconstruction. METHODS:The authors performed a retrospective chart review of patients undergoing open (i.e., nonpercutaneous, minimal access surgery) separation surgery for high-grade epidural spinal cord compression using cement-augmented pedicle screws at single levels adjacent to the decompression level(s). Patient demographics, treatment data, operative complications, and short-term radiographic outcomes were evaluated. RESULTS:Overall, 44 patients met inclusion criteria with radiographic follow-up at a mean of 8.5 months. Involved levels included 19 thoracic, 5 thoracolumbar, and 20 lumbar. Cement augmentation through fenestrated pedicle screws was performed in 30 patients, and a vertebroplasty-type approach was used in the remaining 14 patients to augment screw purchase. One (2%) patient required an operative revision for a hardware complication. Three (7%) nonoperative radiographic hardware complications occurred, including 1 pathologic fracture at the index level causing progressive kyphosis and 2 incidences of haloing around a single screw. There were 2 wound complications that were managed conservatively without operative intervention. No cement-related complications occurred. CONCLUSIONS:Open posterolateral decompression utilizing short-segment cement-augmented pedicle screws is a viable alternative to long-segment instrumentation for reconstruction following separation surgery for metastatic spine tumors. Studies with longer follow-up are needed to determine the rates of delayed complications and the durability of these outcomes.

STUDY DESIGN/METHODS:General population utility valuation study. OBJECTIVE:The aim of this study was to develop a technique for calculating utilities from the Spine Oncology Study Group Outcomes Questionnaire v2.0 (SOSGOQ2.0). SUMMARY OF BACKGROUND DATA/BACKGROUND:The ability to calculate quality-adjusted life-years (QALYs) for metastatic spine disease would enhance treatment decision-making and facilitate economic analysis. QALYs are calculated using utilities. METHODS:Using a hybrid concept-retention and factorial analysis shortening approach, we first shortened the SOSGOQ2.0 to eight items (SOSGOQ-8D). This was done to lessen the cognitive burden of the utility valuation exercise. A general population sample of 2730 adults was then asked to evaluate 12 choice sets based on SOSGOQ-8D health states in a Discrete Choice Experiment. A utility scoring rubric was then developed using a mixed multinomial-logit regression model. RESULTS:We were able to reduce the SOSGOQ2.0 to an SOSGOQ-8D with a mean error of 0.003 and mean absolute error of 3.078 compared to the full questionnaire. The regression model demonstrated good predictive performance and was used to develop a utility scoring rubric. Regression results revealed that participants did not regard all SOSGOQ-8D items as equally important. CONCLUSION/CONCLUSIONS:We provide a simple technique for converting the SOSGOQ2.0 to utilities. The ability to evaluate QALYs in metastatic spine disease will facilitate economic analysis and patient counseling. We also quantify the importance of individual SOSGOQ-8D items. Clinicians should heed these findings and offer treatments that maximize function in the most important items.Level of Evidence: 3.

STUDY DESIGN/UNASSIGNED:International multicenter prospective observational cohort study on patients undergoing radiation +/- surgical intervention for the treatment of symptomatic spinal metastases. OBJECTIVES/UNASSIGNED:To investigate the association between the total Spinal Instability Neoplastic Score (SINS), individual SINS components and PROs. METHODS/UNASSIGNED: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/UNASSIGNED:< 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/UNASSIGNED: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.