Association of surgical resection and survival in patients with malignant primary osseous spinal neoplasms from the Surveillance, Epidemiology, and End Results (SEER) database

Population-based survival analysis of primary spinal chordoma in the US from 2000 to 2020

PURPOSE

Chordomas are rare malignant tumors that occur primarily in the axial skeleton. We seek to analyze trends affecting five-year overall survival (5y OS) among patients with primary spinal chordomas (PSC) of the vertebrae and sacrum/pelvis.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) Program was used to identify patients with PSC (ICD-O-3 histology codes 9370/3, 9371/3, and 9372/3) of the spine or sacrum/pelvis. Multivariate and univariate survival analyses were conducted to assess demographic, disease, or treatment characteristic trends.

RESULTS

Eight-hundred-ninety-six patients diagnosed with PSC were identified. Patients 0-54 years at diagnosis had improved 5y OS compared to those either 55-69 years (HR = 1.78; p = 0.046) or those between 70 and 85 + years (HR = 3.92; p < 0.001). Histology impacted 5y OS: Cox regression demonstrated variance among the three histologies assessed (p < 0.001), while univariate analysis demonstrated patients with dedifferentiated chordoma (1.0% of cohort; 33.3% [1.9,64.7]) and chondroid chordoma (2.0% of cohort; 52.5% [26.1,78.9]) had decreased 5y OS compared to those with general chordoma (72.2% [68.8,75.6]; p < 0.001). Nonmarried patients had decreased 5y OS on univariate analysis (65.2% [59.4,71.0] versus 76.2% [72.0,80.4]), with widowed patients being the primary driver of this on subanalysis. Treatment with gross total resection was associated with increased 5y OS (HR = 0.22, p < 0.001), as was treatment with radiotherapy (HR = 0.69, p = 0.030).

CONCLUSION

Patient age and marital status were significant demographic factors associated with changes in 5y OS among those with PSC. PSC histology is a potentially important prognostic factor in the management of disease.

Chondrosarcoma of the Mobile Spine in the Elderly: A National Cancer Database Study

BACKGROUND

The current research on geriatric patients with spinal chondrosarcoma is limited. This study aimed to investigate the demographics, patterns of care, and survival of geriatric patients with chondrosarcoma of the mobile spine.

METHODS

The National Cancer Database was queried from 2008 to 2018 for geriatric patients (60-89 years) with chondrosarcoma of the mobile spine. The primary outcome of this study was overall survival. The secondary outcome was treatment utilization patterns. Survival analyses were conducted using log-rank tests and Cox proportional hazards regressions. Logistic regression models were utilized to assess correlations between baseline variables and treatment utilization.

RESULTS

The database retrieved 122 patients. While 43.7% of the patients presented with tumors exceeding 5 cm in size, the incidence of regional lymph node involvement or distant metastases was relatively low, affecting only 5% of the patients. Furthermore, 22.3% of the patients had tumors graded as 3-4. The 5-year overall survival rate was 52.9% (95% confidence interval: 42-66.6). The mortality risk was significantly associated with age, tumor grade and stage, and treatment plan. Most patients (79.5%) underwent surgery, while 35.9% and 4.2% were treated with radiotherapy and chemotherapy, respectively. Age, race, comorbidities, geographical region, tumor stage, and healthcare facility type significantly correlated with treatment utilization.

CONCLUSIONS

Surgical resection significantly lowered the mortality risk in geriatric patients with spinal chondrosarcomas. Demographic and geographical factors significantly dictated treatment plans. Further studies are required to assess the role of radiotherapy and chemotherapy in treating these patients in the modern era.

En Bloc Total Vertebrectomy of the Thoracic and Lumbar Spine

Background/Objectives: We evaluated the outcomes of patients undergoing en bloc total vertebrectomy at our institution within the last three decades. The aim of our study was to analyse the oncological and neurological outcomes and the changes over time. Methods: We included 22 consecutive patients treated with a total vertebrectomy at our institution between January 1990 and December 2022. The standard follow-up protocol for sarcoma patients was performed. Early complications were defined as complications within the first three months postoperatively. Local recurrence was defined as the reoccurrence of a tumour at least four months after surgery. Adequate statistical methods were applied to evaluate the survival rates and the influence of potential risk factors. A p-value of <0.05 was considered statistically significant. Results: From 1990 to 2010, five total vertebrectomies were performed each decade, whereas twelve patients underwent the procedure in the period from 2010 to 2022. The mean follow-up period was 101.25 months (±112; 2-339). The one-, five- and ten-year overall survival rates were 91% (CI = (0.79; 1.00)), 59% (CI = (0.37; 0.81)) and 51% (CI = (0.27; 0.75)), respectively. For soft tissue tumours, the average overall survival was 6.2 years, whereas, for bone sarcomas, it was 13.6 years. None of the patients with wide surgical margins developed local recurrence. Complications necessitating revision procedures occurred in 54% of all cases. Conclusions: A total vertebrectomy is a highly demanding procedure, requiring accurate patient selection, meticulous preoperative planning and a highly collaborative interdisciplinary team. Adequate surgical treatment seems to be indispensable when aiming for curative treatment. Owing to the rarity of the indications, this procedure should be restricted to large tumour centres.

Nomograms to predict lung metastasis in malignant primary osseous spinal neoplasms and cancer-specific survival in lung metastasis subgroup

Purpose

To construct and validate nomograms for predicting lung metastasis probability in patients with malignant primary osseous spinal neoplasms (MPOSN) at initial diagnosis and predicting cancer-specific survival (CSS) in the lung metastasis subgroup.

Methods

A total of 1,298 patients with spinal primary osteosarcoma, chondrosarcoma, Ewing sarcoma, and chordoma were retrospectively collected. Least absolute shrinkage and selection operator (LASSO) and multivariate logistic analysis were used to identify the predictors for lung metastasis. LASSO and multivariate Cox analysis were used to identify the prognostic factors for 3- and 5-year CSS in the lung metastasis subgroup. Receiver operating characteristic (ROC) curves, calibration curves, and decision curve analyses (DCA) were used to estimate the accuracy and net benefits of nomograms.

Results

Histologic type, grade, lymph node involvement, tumor size, tumor extension, and other site metastasis were identified as predictors for lung metastasis. The area under the curve (AUC) for the training and validating cohorts were 0.825 and 0.827, respectively. Age, histologic type, surgery at primary site, and grade were identified as the prognostic factors for the CSS. The AUC for the 3- and 5-year CSS were 0.790 and 0.740, respectively. Calibration curves revealed good agreements, and the Hosmer and Lemeshow test identified the models to be well fitted. DCA curves demonstrated that nomograms were clinically useful.

Conclusion

The nomograms constructed and validated by us could provide clinicians with a rapid and user-friendly tool to predict lung metastasis probability in patients with MPOSN at initial diagnosis and make a personalized CSS evaluation for the lung metastasis subgroup.

Machine Learning Predict Survivals of Spinal and Pelvic Ewing's Sarcoma with the SEER Database

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVES

This study aimed to develop survival prediction models for spinal Ewing's sarcoma (EWS) based on machine learning (ML).

METHODS

We extracted the SEER registry's clinical data of EWS diagnosed between 1975 and 2016. Three feature selection methods extracted clinical features. Four ML algorithms (Cox, random survival forest (RSF), CoxBoost, DeepCox) were trained to predict the overall survival (OS) and cancer-specific survival (CSS) of spinal EWS. The concordance index (C-index), integrated Brier score (IBS) and mean area under the curves (AUC) were used to assess the prediction performance of different ML models. The top initial ML models with best performance from each evaluation index (C-index, IBS and mean AUC) were finally stacked to ensemble models which were compared with the traditional TNM stage model by 3-/5-/10-year Receiver Operating Characteristic (ROC) curves and Decision Curve Analysis (DCA).

RESULTS

A total of 741 patients with spinal EWS were identified. C-index, IBS and mean AUC for the final ensemble ML model in predicting OS were .693/0.158/0.829 during independent testing, while .719/0.171/0.819 in predicting CSS. The ensemble ML model also achieved an AUC of .705/0.747/0.851 for predicting 3-/5-/10-year OS during independent testing, while .734/0.779/0.830 for predicting 3-/5-/10-year CSS, both of which outperformed the traditional TNM stage. DCA curves also showed the advantages of the ensemble models over the traditional TNM stage.

CONCLUSION

ML was an effective and promising technique in predicting survival of spinal EWS, and the ensemble models were superior to the traditional TNM stage model.

Racial disparities in the management and outcomes of primary osseous neoplasms of the spine: a SEER analysis

PURPOSE

Primary osseous neoplasms of the spine, including Ewing's sarcoma, osteosarcoma, chondrosarcoma, and chordoma, are rare tumors with significant morbidity and mortality. The present study aims to identify the prevalence and impact of racial disparities on management and outcomes of patients with these malignancies.

METHODS

The 2000 to 2020 Surveillance, Epidemiology, and End Results (SEER) Registry, a cancer registry, was retrospectively reviewed to identify patients with Ewing's sarcoma, osteosarcoma, chondrosarcoma, or chordoma of the vertebral column or sacrum/pelvis. Study patients were divided into race-based cohorts: White, Black, Hispanic, and Other. Demographics, tumor characteristics, treatment variables, and mortality were assessed.

RESULTS

2,415 patients were identified, of which 69.8% were White, 5.8% Black, 16.1% Hispanic, and 8.4% classified as "Other". Tumor type varied significantly between cohorts, with osteosarcoma affecting a greater proportion of Black patients compared to the others (p < 0.001). A lower proportion of Black and Other race patients received surgery compared to White and Hispanic patients (p < 0.001). Utilization of chemotherapy was highest in the Hispanic cohort (p < 0.001), though use of radiotherapy was similar across cohorts (p = 0.123). Five-year survival (p < 0.001) and median survival were greatest in White patients (p < 0.001). Compared to non-Hispanic Whites, Hispanic (p < 0.001) and "Other" patients (p < 0.001) were associated with reduced survival.

CONCLUSION

Race may be associated with tumor characteristics at diagnosis (including subtype, size, and site), treatment utilization, and mortality, with non-White patients having lower survival compared to White patients. Further studies are necessary to identify underlying causes of these disparities and solutions for eliminating them.

Disparities in Primary Spinal Osseous Malignant Bone Tumor Survival by Medicaid Status: A National Population-Based Risk Analysis

BACKGROUND

The impact of Medicaid status on survival outcomes of patients with spinal primary malignant bone tumors (sPMBT) has not been investigated.

METHODS

Using the SEER-Medicaid database, adults diagnosed between 2006 and 2013 with sPMBT including chordoma, osteosarcoma, chondrosarcoma, Ewing sarcoma, or malignant giant cell tumor (GCT) were studied. Five-year survival analysis was performed using the Kaplan-Meier method. Adjusted survival analysis was performed using Cox proportional-hazards regression controlling for age, sex, marital status, cancer stage, poverty level, vertebral versus sacral location, geography, rurality, tumor diameter, tumor grade, tumor histology, and therapy.

RESULTS

A total of 572 patients with sPMBT (Medicaid: 59, non-Medicaid: 513) were identified. Medicaid patients were more likely to be younger (P < 0.001), Black (P < 0.001), live in high poverty neighborhoods (P = 0.006), have distant metastases at diagnosis (P < 0.001), and less likely to receive surgery (P = 0.006). The 5-year survival rate was 65.7% (chondrosarcoma: 70.0%, chordoma: 91.5%, Ewing sarcoma: 44.6%, GCT: 90.0%, osteosarcoma: 34.2%). Medicaid patients had significantly worse 5-year survival than non-Medicaid patients (52.0% vs. 67.2%, P = 0.02). Minority individuals on Medicaid were associated with an increased risk of cancer-specific mortality compared with White non-Medicaid patients (adjusted hazard ratio [aHR] = 2.51, [95% CI 1.18-5.35], P = 0.017). Among Medicaid patients, those who received surgery had significantly better survival than those who did not (64.5% vs. 30.6%, P = 0.001). For all patients, not receiving surgery (aHR = 1.90 [1.23-2.95], P = 0.004) and tumor diameter >50 mm (aHR=1.89 [1.10-3.25], P = 0.023) were associated with an increased risk of mortality.

CONCLUSIONS

Medicaid patients may be less likely to receive surgery and suffer from poorer survival. These disparities may be especially prominent among minorities.

Construction of a Tool to Predict Overall Survival of Patients With Primary Spinal Tumors After Surgical Resection: A Real-World Analysis Based on the Surveillance, Epidemiology, and End Results Database

BACKGROUND

We aim to construct a practical clinical prediction model to accurately evaluate the overall survival (OS) of patients with primary spinal tumors after primary tumor resection, thereby aiding clinical decision-making.

METHODS

A total of 695 patients diagnosed with a primary spinal tumor, selected from the Surveillance, Epidemiology, and End Results (SEER) database, were included in this study. The Cox regression algorithm was applied to the training cohort to build the prognostic nomogram model. The nomogram's performance in terms of discrimination, calibration, and clinical usefulness was also assessed in the internal SEER validation cohort. The fitted prognostic nomogram was then used to create a web-based calculator.

RESULTS

Four independent prognostic factors were identified to establish a nomogram model for patients with primary spinal tumors who had undergone surgical resection. The C-index (.757 for the training cohort and .681 for the validation cohort) and the area under the curve values over time (both >.68) showed that the model exhibited satisfactory discrimination in both the SEER cohort. The calibration curve revealed that the projected and actual survival rates are very similar. The decision curve analysis also revealed that the model is clinically valuable and capable of identifying high-risk patients.

CONCLUSIONS

After developing a nomogram and a web-based calculator, we were able to reliably forecast the postoperative OS of patients with primary spinal tumors. These tools are expected to play an important role in clinical practice, informing clinicians in making decisions about patient care after surgery.

Establishment and validation of systematic prognostic nomograms in patients over 60 years of age with osteosarcoma: A multicenter external verification study

BACKGROUND

The aim of this study was to develop and validate systematic nomograms to predict cancer specific survival (CSS) and overall survival (OS) in osteosarcoma patients aged over 60 years.

METHODS

We used data from the Surveillance, Epidemiology, and End Results (SEER) database and identified 982 patients with osteosarcoma over 60 years of age diagnosed between 2004 and 2015. Overall, 306 patients met the requirements for the training group. Next, we enrolled 56 patients who met the study requirements from multiple medical centers as the external validation group to validate and analyze our model. We collected all available variables and finally selected eight that were statistically associated with CSS and OS through Cox regression analysis. Integrating the identified variables, we constructed 3- and 5-year OS and CSS nomograms, respectively, which were further evaluated by calculating the C-index. A calibration curve was used to evaluate the accuracy of the model. Receiver operating characteristic (ROC) curves measured the predictive capacity of the nomograms. The Kaplan-Meier analysis was used for all patient-based variables to explore the influence of various factors on patient survival. Finally, a decision curve analysis (DCA) curve was used to analyze whether our model would be suitable for application in clinical practice.

RESULTS

Cox regression analysis of clinical variables identified age, sex, marital status, tumor grade, tumor laterality, tumor size, M-stage, and surgical treatment as prognostic factors. Nomograms showed good predictive capacity for OS and CSS. We calculated that the C-index of the OS nomogram of the training population was 0.827 (95% CI 0.778-0.876), while that of the CSS nomogram was 0.722 (95% CI 0.665-0.779). The C-index of the OS nomogram evaluated on the external validation population was 0.716 (95% CI 0.575-0.857), while that of the CSS nomogram was 0.642 (95% CI 0.50-0.788). Furthermore, the calibration curve of our prediction models indicated the nomograms could accurately predict patient outcome.

CONCLUSIONS

The constructed nomogram is a useful tool for accurately predicting OS and CSS at 3 and 5 years for patients over 60 years of age with osteosarcoma and can assist clinicians in making appropriate decisions in practice.

Development and validation of nomograms predicting overall and cancer-specific survival for non-metastatic primary malignant bone tumor of spine patients

At present, no study has established a survival prediction model for non-metastatic primary malignant bone tumors of the spine (PMBS) patients. The clinical features and prognostic limitations of PMBS patients still require further exploration. Data on patients with non-metastatic PBMS from 2004 to 2015 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Multivariate regression analysis using Cox, Best-subset and Lasso regression methods was performed to identify the best combination of independent predictors. Then two nomograms were structured based on these factors for overall survival (OS) and cancer-specific survival (CSS). The accuracy and applicability of the nomograms were assessed by area under the curve (AUC) values, calibration curves and decision curve analysis (DCA). Results: The C-index indicated that the nomograms of OS (C-index 0.753) and CSS (C-index 0.812) had good discriminative power. The calibration curve displays a great match between the model's predictions and actual observations. DCA curves show our models for OS (range: 0.09-0.741) and CSS (range: 0.075-0.580) have clinical value within a specific threshold probability range compared with the two extreme cases. Two nomograms and web-based survival calculators based on established clinical characteristics was developed for OS and CSS. These can provide a reference for clinicians to formulate treatment plans for patients.

Primary Sarcomas of the Spine: A Systematic Review and Pooled Data Analysis

STUDY DESIGN

A systematic review of the literature and pooled data analysis of treatment outcomes of primary sarcomas of the spine.

OBJECTIVE

To examine the current literature and treatment options for primary sarcomas of the spine.

SUMMARY OF BACKGROUND DATA

A paucity of literature exists on treatment outcomes of primary sarcomas of the spine.

MATERIALS AND METHODS

Two authors searched PubMed to identify articles for review, and a pooled data analysis was performed to determine overall survival for each type of surgical resection on spine sarcomas.

RESULTS

In total, 1776 articles were identified, and 11 met our inclusion criteria for review. In chondrosarcoma, overall survival was significantly higher with en bloc excision when compared with piecemeal resection (HR for piecemeal resection: 4.11; 95% CI: 2.08-8.15). Subgroup analysis showed that the addition of radiation therapy after piecemeal excision increased overall survival to 60 months from 48 months with piecemeal excision alone. In osteosarcoma, there was no significant difference in overall survival between en bloc and piecemeal resection (HR for piecemeal resection: 1.76; 95% CI: 0.776-3.99). In Ewing's sarcoma, overall survival was significantly higher when a successful en bloc resection was achieved and coupled with chemotherapy and radiation therapy for local control (HR for piecemeal resection: 7.96; 95% CI: 2.12-20.1). Interestingly, when a successful en bloc resection could not be achieved, chemotherapy and radiation therapy alone had significantly higher survival than piecemeal resection (HR for piecemeal resection: 2.63; 95% CI: 1.01-6.84). A significantly higher number of local recurrences were associated with the piecemeal resection group in all types of spine sarcomas.

CONCLUSION

This review and pooled data seem to favor en bloc excision for local control as the treatment of choice in primary sarcomas of the spine.

Survival of Patients With Primary Osseous Malignancies of the Mobile Spine Is Associated With Access to "Standard Treatment" Protocols

INTRODUCTION

Malignancies of the mobile spine carry high morbidity and mortality. This study sought to examine factors associated with receipt of "standard" treatment and survival for patients with primary mobile spine tumors in the California Cancer Registry (CCR).

METHODS

The CCR (1988 to 2016) data were obtained for patients with primary tumors of the mobile spine and at least 1-year follow-up. Sacrum/pelvis tumors were excluded. Age at diagnosis, sex, race, neighborhood socioeconomic status, insurance, Charlson Comorbidity Index, histologic diagnosis, stage at diagnosis, and treatment at a National Cancer Institute-designated Cancer Center (NCICC) were collected. Multivariate analyses were done to identify factors associated with all-cause mortality and receipt of "standard" treatment.

RESULTS

Four hundred eighty-four patients (64% White, 56% low neighborhood socioeconomic status, and 36% privately insured) were included. Chordoma (37%) was the most common diagnosis. Only 16% had metastatic disease at presentation. Only 29% received treatment at an NCICC. Lower age, Charlson Comorbidity Index, less extensive stage of disease, and private insurance were associated with lower all-cause mortality (all P < 0.05). Medicaid/public insurance (hazard ratio [HR], 1.65; 95% confidence interval [CI], 1.13 to 2.41) and Medicare (HR, 1.80; 95% CI, 1.25 to 2.59) were associated with higher mortality compared with private insurance. Patients who received no known treatment (HR, 2.41; CI, 1.51 to 3.84) or treatment other than the "standard" (HR, 1.45; CI, 1.11 to 1.91) had higher mortality compared with those who received the standard protocols. A critical predictor of receiving the standard treatment protocol was being treated at an NCICC. If patients did not receive care at such institutions, they received optimal treatment only 40% of the time (HR, 0.5; P = 0.004).

CONCLUSIONS

Receipt of defined "standard treatment" protocols was associated with care received at an NCICC and lower all-cause mortality in patients with primary osseous malignancies of the mobile spine. Patients with public insurance are vulnerable to worse outcomes, regardless of age, disease burden, or receipt of standard treatment.

LEVEL OF EVIDENCE

III.

Individualized assessment of risk and overall survival in patients newly diagnosed with primary osseous spinal neoplasms with synchronous distant metastasis

Background

The prognosis of patients with primary osseous spinal neoplasms (POSNs) presented with distant metastases (DMs) is still poor. This study aimed to evaluate the independent risk and prognostic factors in this population and then develop two web-based models to predict the probability of DM in patients with POSNs and the overall survival (OS) rate of patients with DM.

Methods

The data of patients with POSNs diagnosed between 2004 and 2017 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate logistics regression analyses were used to study the risk factors of DM. Based on independent DM-related variables, we developed a diagnostic nomogram to estimate the risk of DM in patients with POSNs. Among all patients with POSNs, those who had synchronous DM were included in the prognostic cohort for investigating the prognostic factors by using Cox regression analysis, and then a nomogram incorporating predictors was developed to predict the OS of patients with POSNs with DM. Kaplan-Meier (K-M) survival analysis was conducted to study the survival difference. In addition, validation of these nomograms were performed by using receiver operating characteristic (ROC) curves, the area under curves (AUCs), calibration curves, and decision curve analysis (DCA).

Results

A total of 1345 patients with POSNs were included in the study, of which 238 cases (17.70%) had synchronous DM at the initial diagnosis. K-M survival analysis and multivariate Cox regression analysis showed that patients with DM had poorer prognosis. Grade, T stage, N stage, and histological type were found to be significantly associated with DM in patients with POSNs. Age, surgery, and histological type were identified as independent prognostic factors of patients with POSNs with DM. Subsequently, two nomograms and their online versions (https://yxyx.shinyapps.io/RiskofDMin/ and https://yxyx.shinyapps.io/SurvivalPOSNs/) were developed. The results of ROC curves, calibration curves, DCA, and K-M survival analysis together showed the excellent predictive accuracy and clinical utility of these newly proposed nomograms.

Conclusion

We developed two well-validated nomograms to accurately quantify the probability of DM in patients with POSNs and predict the OS rate in patients with DM, which were expected to be useful tools to facilitate individualized clinical management of these patients.

Risk stratification system and web-based nomogram constructed for predicting the overall survival of primary osteosarcoma patients after surgical resection

Background

Previous prediction models of osteosarcoma have not focused on survival in patients undergoing surgery, nor have they distinguished and compared prognostic differences among amputation, radical and local resection. This study aimed to establish and validate the first reliable prognostic nomogram to accurately predict overall survival (OS) after surgical resection in patients with osteosarcoma. On this basis, we constructed a risk stratification system and a web-based nomogram.

Methods

We enrolled all patients with primary osteosarcoma who underwent surgery between 2004 and 2015 in the Surveillance, Epidemiology, and End Results (SEER) database. In patients with primary osteosarcoma after surgical resection, univariate and multivariate cox proportional hazards regression analyses were utilized to identify independent prognostic factors and construct a novel nomogram for the 1-, 3-, and 5-year OS. Then the nomogram's predictive performance and clinical utility were evaluated by the concordance index (C-index), receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA).

Result

This study recruited 1,396 patients in all, with 837 serving as the training set (60%) and 559 as the validation set (40%). After COX regression analysis, we identified seven independent prognostic factors to develop the nomogram, including age, primary site, histological type, disease stage, AJCC stage, tumor size, and surgical method. The C-index indicated that this nomogram is considerably more accurate than the AJCC stage in predicting OS [Training set (HR: 0.741, 95% CI: 0.726–0.755) vs. (HR: 0.632, 95% CI: 0.619–0.645); Validation set (HR: 0.735, 95% CI: 0.718–0.753) vs. (HR: 0.635, 95% CI: 0.619–0.652)]. Moreover, the area under ROC curves, the calibration curves, and DCA demonstrated that this nomogram was significantly superior to the AJCC stage, with better predictive performance and more net clinical benefits.

Conclusion

This study highlighted that radical surgery was the first choice for patients with primary osteosarcoma since it provided the best survival prognosis. We have established and validated a novel nomogram that could objectively predict the overall survival of patients with primary osteosarcoma after surgical resection. Furthermore, a risk stratification system and a web-based nomogram could be applied in clinical practice to assist in therapeutic decision-making.

Does Primary Tumor Resection in Patients with Metastatic Primary Mobile Vertebral Column Sarcoma Improve Survival?

BACKGROUND

Primary mobile vertebral column sarcoma is an exceedingly rare malignancy. Although primary tumor resection has been reported to prolong survival in patients with metastatic bone sarcoma, whether primary tumor resection in patients with advanced primary mobile vertebral column sarcoma is associated with survival remains unclear owing to the rarity of this pathological entity.

METHODS

Using the Surveillance, Epidemiology, and End Results database, 182 patients with metastatic primary mobile vertebral column sarcoma were identified between 1983 and 2015. Of the 182 patients enrolled, 101 patients (55%) underwent primary tumor resection (Surgery group) and 81 patients (45%) did not undergo resection (No Surgery group). To account for imbalances in the basic characteristics of patients between groups, propensity score matching was performed. Survival analysis was performed by weighted Cox proportional hazards modeling to calculate hazard ratios.

RESULTS

After adjusting for patient background characteristics, 138 patients were included for the analysis (Surgery group: 69 patients; No Surgery group: 69 patients). The Surgery group did not show improved cancer-specific survival (hazard ratio = 0.73, 95% CI 0.49-1.10). Similarly, the Surgery group did not show improved overall survival compared with the No Surgery group (hazard ratio = 0.80, 95% CI 0.55-1.16).

CONCLUSIONS

To our knowledge, this is the first study to indicate that surgical resection for advanced primary mobile vertebral column sarcoma does not have a positive impact on survival.

Surgery Has Positive Effects on Spinal Osteosarcoma Prognosis: A Population-Based Database Study

OBJECTIVE

The treatment of osteosarcoma of the spine remains controversial. Our aim was to explore the treatment of patients with spinal osteosarcoma.

METHODS

We analyzed the data from 727 spinal osteosarcoma patients from the Surveillance, Epidemiology, and End Results database from 1973 to 2015. X-tile software was used to find the optimal cutoff values for age and economic income. The Kaplan-Meier estimator method was used to analyze overall survival and cancer-specific survival. Univariate and multivariate Cox analyses were used to identify the independent prognostic factors. Propensity score matching was used to reduce the possibility of selection bias. A logistic regression model was used to clarify the relevant factors affecting a patient's decision to undergo surgery.

RESULTS

Among 727 eligible spinal osteosarcoma patients, 370 (50.9%) had undergone surgery and 357 (49.1%) had not undergone surgery. Significant differences were found in the effects of patient age at diagnosis, Surveillance, Epidemiology, and End Results historical stage, and tumor grade on the patients' decision to undergo surgery (P < 0.05). Surgery was an independent prognostic factor for overall survival and cancer-specific survival of patients with spinal osteosarcoma. The same results were found after 1:1 propensity score matching. The surgery group had more favorable survival compared with the nonsurgery group.

CONCLUSIONS

Surgery can provide survival benefits for patients with osteosarcoma of the spine. The patients with spinal osteosarcoma who had undergone surgery experienced favorable survival benefits. Thus, surgery can be a suitable treatment for patients with spinal osteosarcoma.

A Web-Based Prediction Model for Overall Survival of Elderly Patients With Malignant Bone Tumors: A Population-Based Study

Background: Malignant bone tumors (MBT) are one of the causes of death in elderly patients. The purpose of our study is to establish a nomogram to predict the overall survival (OS) of elderly patients with MBT.

Methods: The clinicopathological data of all elderly patients with MBT from 2004 to 2018 were downloaded from the SEER database. They were randomly assigned to the training set (70%) and validation set (30%). Univariate and multivariate Cox regression analysis was used to identify independent risk factors for elderly patients with MBT. A nomogram was built based on these risk factors to predict the 1-, 3-, and 5-year OS of elderly patients with MBT. Then, used the consistency index (C-index), calibration curve, and the area under the receiver operating curve (AUC) to evaluate the accuracy and discrimination of the prediction model was. Decision curve analysis (DCA) was used to assess the clinical potential application value of the nomogram. Based on the scores on the nomogram, patients were divided into high- and low-risk groups. The Kaplan-Meier (K-M) curve was used to test the difference in survival between the two patients.

Results: A total of 1,641 patients were included, and they were randomly assigned to the training set (N = 1,156) and the validation set (N = 485). The univariate and multivariate analysis of the training set suggested that age, sex, race, primary site, histologic type, grade, stage, M stage, surgery, and tumor size were independent risk factors for elderly patients with MBT. The C-index of the training set and the validation set were 0.779 [0.759–0.799] and 0.801 [0.772–0.830], respectively. The AUC of the training and validation sets also showed similar results. The calibration curves of the training and validation sets indicated that the observed and predicted values were highly consistent. DCA suggested that the nomogram had potential clinical value compared with traditional TNM staging.

Conclusion: We had established a new nomogram to predict the 1-, 3-, 5-year OS of elderly patients with MBT. This predictive model can help doctors and patients develop treatment plans and follow-up strategies.

Prevalence, Risk Factors, and Prognostic Factors of Primary Malignant Bone Neoplasms with Bone Metastasis at Initial Diagnosis: A Population-Based Study

Background. Bone metastasis (BM) has been proven to be responsible for the poor prognosis of primary malignant bone neoplasms (PMBNs). We aimed to identify the prevalence, risk factors, and prognostic factors for PMBNs patients with BM based on the Surveillance, Epidemiology, and End Results (SEER) database. Methods. 4,758 patients diagnosed with PMBNs from 2010 to 2018 were selected from the SEER database. All patients were divided into two groups: the BM group or the non-BM group. Pearson’s chi-square test and Fisher’s exact method were used to assess baseline characteristics, and logistic regression analysis was applied to assess risk factors. In addition, a nomogram was constructed based on the results of Cox regression analysis among 227 patients with BM. The good performance and clinical applicability of the nomogram were tested by the concordance index, operating characteristic curve, area under the curve, calibration curves, and decision curve analysis. Results. 227 (4.8%) patients had metastasis to bone at diagnosis. Primary site outside the extremities (axial: odds ratio, $\text{OR}=1.770$ ; others: $\text{OR}=1.951$ ), Ewing sarcoma ( $\text{OR}=2.845$ ), larger tumor size (5–8 cm: $\text{OR}=3.403$ ; >8 cm: $\text{OR}=5.562$ ), tumor extension beyond the periosteum ( $\text{OR}=2.477$ ), and regional lymph node metastasis ( $\text{OR}=2.900$ ) were associated with a higher risk of BM at the initial diagnosis of PMBNs. Five independent prognostic factors were found in the survival analysis: pathological type (chondrosarcoma vs. osteosarcoma: hazard ratio, $\text{HR}=0.342$ ; Ewing sarcoma vs. osteosarcoma: $\text{HR}=0.592$ ; and chordoma vs. osteosarcoma: $\text{HR}=0.015$ ), marital status ( $\text{HR}=2.457$ ), pulmonary metastasis ( $\text{HR}=1.934$ ), surgery at the primary site ( $\text{HR}=0.164$ ), and chemotherapy ( $\text{HR}=0.084$ ). A nomogram based on these prognostic factors could be a good predictor of cancer-specific survival. Conclusions. We identified the prevalence, risk factors, and prognostic factors correlated with BM in PMBNs patients. The related nomogram could be a practical tool for therapeutic decision-making and individual counseling.

Proton Therapy for Primary Bone Malignancy of the Pelvic and Lumbar Region - Data From the Prospective Registries ProReg and KiProReg

PURPOSE/OBJECTIVES

Multimodality treatments together with local proton therapy (PT) are commonly used in unresectable primary bone malignancies in order to provide better tumor control rate while maintaining good feasibility. The aim of this study is to provide data on outcome of PT for the challenging cohort of pelvic and lumbar bone tumors.

METHODS AND MATERIALS

This retrospective study includes all patients with primary bone malignancy of the pelvis and lumbar spine receiving PT in our institution between May 2013 and December 2019 enrolled in the prospective registries KiProReg and ProReg collecting information on demographics, treatment, tumor characteristics, toxicities, and outcome.

RESULTS

Eighty-one patients were enrolled with a median age of 19.7 years (1.3-85.8). The median follow-up time was 27.5 months (1.2-83.2). The majority of patients was male (64.2%), ECOG status of 0-1 (75.2%), underwent only biopsy (50.6%), received chemotherapy (69.1%) and was assigned for definite PT (70.4%). The predominant tumor characteristics were as follows: Ewing's sarcoma histology (58%), negative nodal involvement (97.5%) and no metastasis at diagnosis (81.5%). Median maximal diameter of tumor was 8 cm (1.4-20). LC, EFS and OS rate were 76.5, 60, and 88.1% at two years and 72.9, 45.7, and 68.9% at three years, respectively. Age over 20 years was a significant negative factor for LC, EFS, and OS. Metastatic disease at initial diagnosis affected OS and ECOG status of 2-4 affected EFS only. Regarding 17 relapsed cases (21%), isolated distant relapse was the most common failure (46.9%) followed by local failure (40.6%). Eleven out of 14 evaluable patients relapsed within high-dose region of radiotherapy. Acute grade 3-4 toxicity was found in 41 patients (50.6%) and all toxicities were manageable. Late grade 3 toxicity was reported in 7 patients (10.4%) without any of grade 4. Most common higher grade acute and late side effects concerned hematologic and musculoskeletal toxicity.

CONCLUSION

Proton therapy resulted in good oncological outcomes when being part of the multimodality treatment for pelvic and lumbar primary bone malignancies. However, distant metastases and local failures within the high-dose region of radiotherapy are still a common issue. Acute and late toxicities of combined therapy were acceptable.

Chondrosarcoma of the spine: a narrative review

Chondrosarcoma is an uncommon primary bone tumor with an estimated incidence of 0.5 per 100,000 patient-years. Primary chondrosarcoma of the mobile spine and sacrum cumulatively account for less than 20% of all cases, most .commonly causing patients to present with focal pain with or without radiculopathy, or myelopathy secondary to neural element compression. Because of the rarity, patients benefit from multidisciplinary care at academic tertiary-care centers. Current standard-of-care consists of en bloc surgical resection with negative margins; for high grade lesions adjuvant focused radiation with ≥60 gray equivalents is taking an increased role in improving local control. Prognosis is dictated by lesion grade at the time of resection. Several groups have put forth survival calculators and epidemiological evidence suggests prognosis is quite good for lesions receiving R0 resection. Future efforts will be focused on identifying potential chemotherapeutic adjuvants and refining radiation treatments as a means of improving local control.

Identifying the Risk Factors and Estimating the Prognosis in Patients with Pelvis and Spine Ewing Sarcoma: A Population-Based Study

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

The study was designed to: (1) figure out risk factors of metastasis; (2) explore prognostic factors and develop a nomogram for pelvis and spine Ewing sarcoma (PSES).

SUMMARY OF BACKGROUND DATA

Tools to predict survival of PSES are still insufficient. Nomogram has been widely developed in clinical oncology. Moreover, risk factors of PSES metastasis are still unclear.

METHODS

The data were collected and analyzed from the Surveillance, Epidemiology, and End Results (SEER) database. The optimal cutoff values of continuous variables were identified by X-tile software. The prognostic factors of survival were performed by Kaplan-Meier method and multivariate Cox proportional hazards modeling. Nomograms were further constructed for estimating 3- and 5-year cancer-specific survival (CSS) and overall survival (OS) by using R with rms package. Meanwhile, Pearson χ2 test or Fisher exact test, and logistic regression analysis were used to analyze the risk factors for the metastasis of PSES.

RESULTS

A total of 371 patients were included in this study. The 3- and 5-year CSS and OS rate were 65.8 ± 2.6%, 55.2 ± 2.9% and 64.3 ± 2.6%, 54.1 ± 2.8%, respectively. The year of diagnosis, tumor size, and lymph node invasion were associated with metastasis of patients with PSES. A nomogram was developed based on identified factors including: age, tumor extent, tumor size, and primary site surgery. The concordance index (C-index) of CSS and OS were 0.680 and 0.679, respectively. The calibration plot showed the similar trend of 3-year, 5-year CSS, and OS of PSES patients between nomogram-based prediction and actual observation, respectively.

CONCLUSION

PSES patients with earlier diagnostic year (before 2010), larger tumor size (>59 mm), and lymph node invasion, are more likely to have metastasis. We developed a nomogram based on age, tumor extent, tumor size, and surgical treatments for determining the prognosis for patients with PSES, while more external patient cohorts are warranted for validation.Level of Evidence: 3.

Prognostic Nomograms to Predict Overall Survival and Cancer-specific Survival in Sacrum/Pelvic Chondrosarcoma (SC) Patients: A Population-based Propensity Score-matched Study

STUDY DESIGN

A longitudinal cohort study.

OBJECTIVE

The objective of this study was to evaluate the prognostic factors and determine the difference between different surgery scopes. Nomograms were constructed and validated to predict overall survival (OS) and cancer-specific survival (CSS) of sacrum/pelvic chondrosarcoma (SC) patients.

SUMMARY OF BACKGROUND DATA

Chondrosarcoma is a bone malignancy which is reported to be resistant to both chemotherapy and radiotherapy. Therefore, surgery is the most preferred treatment method. However, this remains a great challenge due to the complex anatomy of the area.

MATERIALS AND METHODS

Data from the Surveillance, Epidemiology, and End Results (SEER) database of patients with conventional SC between 1998 and 2016 was retrieved for analysis. Cox analysis was used to estimate the mortality hazards ratios among patients. Propensity score matching was used to compare different surgery scope. Nomograms were constructed to predict the OS and CSS of patients with SC.

RESULTS

A total of 377 patients were included in this study. The cutoff value for tumor size was considered to be 118 mm. The concordance indices (C-index) value for nomogram predictions of CSS were 0.871. Following propensity score matching, 158 patients were selected for the second time and its result showed no significant difference between the scope of surgery.

CONCLUSIONS

Tumor size was considered to be closely related to the outcome of SC. There is no significant difference in the scope of surgery and limb salvage can be considered. The nomograms can precisely predict OS and CSS in patients with SC. These could help clinicians to perform survival assessments and identify patients at high risk.

LEVEL OF EVIDENCE

Level IV.

Chordoma of the sacrum and mobile spine: a narrative review

Chordoma is a notochord-derived primary tumor of the skull base and vertebral column known to affect 0.08 to 0.5 per 100,000 persons worldwide. Patients commonly present with mechanical, midline pain with or without radicular features secondary to nerve root compression. Management of these lesions has classically revolved around oncologic resection, defined by en bloc resection of the lesion with negative margins as this was found to significantly improve both local control and overall survival. With advancement in radiation modalities, namely the increased availability of focused photon therapy and proton beam radiation, high-dose (>50 Gy) neoadjuvant or adjuvant radiotherapy is also becoming a standard of care. At present chemotherapy does not appear to have a role, but ongoing investigations into the ontogeny and molecular pathophysiology of chordoma promise to identify therapeutic targets that may further alter this paradigm. In this narrative review we describe the epidemiology, histopathology, diagnosis, and treatment of chordoma.

Managing axial bone sarcomas in childhood

Introduction: Axial osteosarcoma and Ewing sarcoma are rare, aggressive neoplasms with a worse prognosis than with tumors involving the extremities because they are more likely to be associated with larger tumor volumes, older age, primary metastases, and a poor histological response to chemotherapy. The 5-year OS rates are reportedly in the range of 18-41% for axial osteosarcoma, and 46-64% for Ewing sarcoma.Area covered: The treatment of axial bone tumors is the same as for extremity bone tumors, and includes chemotherapy, surgery and/or radiotherapy.Expert opinion: Local treatment of axial tumors is particularly difficult due to their proximity to neurological and vascular structures, which often makes extensive and en bloc resections impossible without causing significant morbidity. The incidence of local relapse is consequently high, and this is the main issue in the treatment of these tumors. Radiotherapy is an option in the case of surgical resections with close or positive margins, as well as for inoperable tumors. Delivering high doses of RT to the spinal cord can be dangerous. Given the complexity and rarity of these tumors, it is essential for this subset of patients to be treated at selected reference institutions with specific expertise and multidisciplinary skills.

Homogenous and Heterogenous Prognostic Factors for Patients with Bone Sarcoma

Objective

The aim of this study was to examine the survival rate of patients with different bone sarcomas and to investigate homogenous and heterogenous prognostic factors for different types of bone sarcomas.

Methods

This is a retrospective analysis of records from the Surveillance, Epidemiology, and End Result (SEER) database. Clear information on the distant metastasis of cancer is provided in the SEER database for patients diagnosed between January 2010 and December 2016. Data for the four types of malignant bone sarcomas were extracted, including osteosarcoma, chondrosarcoma, Ewing sarcoma, and chordoma. Patients with bone sarcomas originated from other sites, diagnosed at autopsy, or indicated in death certification were excluded. The overall survival was calculated for the entire cohort and across different bone sarcomas using the Kaplan–Meier method. A subgroup analysis of the different survival rates of four types of bone sarcomas in various levels of each variable was conducted and the differences were tested with the log‐rank test. Cox proportional hazard regression analysis was performed to determine the prognostic factors. Variables with P < 0.05 in the univariate Cox regression analysis were further analyzed using a multivariate Cox regression analysis. The prognostic factors in four groups of bone sarcomas were compared to determine the homogenous and heterogenous factors.

Results

A total of 4732 patients were included with a follow up of 25 (0–83) months. The mean age of patients was 39.7 ± 24.1 years. The 1‐year, 3‐year, and 5‐year overall survival rate for the entire cohort was 86.2% (95% confidence interval [CI]: 85.2%–87.2%), 70.5% (95% CI: 68.9%–72.1%), and 63.0% (95% CI: 61.2%–64.8%), respectively. Factors including age older than 40 years, higher grade, regional and distant stage, tumor in the extremities, T2 stage, bone and lung metastases, and non‐surgery were significantly associated with the poor survival of the entire cohort. The mean overall survival duration of patients with chordoma, chondrosarcoma, Ewing sarcoma, and osteosarcoma was 66.86 (95% CI: 64.06–69.66), 63.53 (95% CI: 61.81–65.25), 58.06 (95% CI: 55.49–60.62) and 54.91 (95% CI: 53.14–56.69) months, respectively. Compared with chordoma, the hazard ratio (HR) and 95% CI for patients with chondrosarcoma, Ewing sarcoma, and osteosarcoma were 1.30 (95% CI: 1.04–1.62; P = 0.023), 1.69 (95% CI: 1.33–2.14; P < 0.001), and 2.00 (95% CI: 1.61–2.48; P <0.001), respectively. Different bone sarcomas showed homogenous and heterogenous prognostic factors.

Conclusion

Different clinicopathological characteristics and prognoses were revealed in patients with osteosarcoma, chondrosarcoma, Ewing sarcoma, and chordoma. The risk factors can potentially guide prognostic prediction and sarcoma‐specific treatment.

Does facility volume influence survival in patients with primary malignant bone tumors of the vertebral column? A comparative cohort study

BACKGROUND CONTEXT

Facility volume has been correlated with survival in many cancers. This relationship has not been established in primary malignant bone tumors of the vertebral column (BTVC).

PURPOSE

To investigate whether facility patient volume is associated with overall survival in patients with primary malignant BTVCs.

STUDY DESIGN

Retrospective comparative cohort.

PATIENT SAMPLE

Adult patients with chordomas, chondrosarcomas, or osteosarcomas of the mobile spine.

OUTCOME MEASURES

Five-year survival.

METHODS

We retrospectively analyzed 733 patients with primary malignant BTVCs in the national cancer database from 2004 through 2015. Univariate and multivariate analyses were used to correlate specific outcome measures with facility volume. Volume was stratified based on cumulative martingale residuals to determine the inflection point of negative to positive impact on survival based on the patient cohort. Long-term survival was compared between patients treated at high and low volume using the Kaplan-Meier method. Only patients with malignant primary tumors were considered eligible for inclusion; patients with incomplete treatment data or benign tumors were excluded.

RESULTS

Patients treated at high-volume centers (HVCs) were younger (p=.0003) and more likely to be insured (p<.0001). There were no significant differences in tumor characteristics. Patients treated at high-volume facilities had improved 5-year survival of 71% versus 58% at low-volume centers (p<.0001). Patients treated at HVCs were more likely to receive surgical treatment (91% vs. 80%, p<.0001); if surgery was performed, they were more likely to undergo an en bloc resection (48% vs. 30%, p<.0001). However, there were no differences in margin status or utilization of radiotherapy or chemotherapy between HVCs and low-volume centers. In a multivariate analysis, facility volume was independently associated with improved survival overall (HR 0.75 [0.58-0.97], p=.03).

CONCLUSIONS

Primary malignant BTVCs are rare, even for HVCs. Despite this, patient survival was significantly improved when treatment was performed at HVCs.

A Nomogram and a Risk Classification System Predicting the Cancer-Specific Survival of Patients With Initially-Diagnosed Osseous Spinal and Pelvic Tumors

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

Our goal was to provide a predictive model and a risk classification system that predicts cancer-specific survival (CSS) from spinal and pelvic tumors.

SUMMARY OF BACKGROUND DATA

Primary bone tumors of the spinal and pelvic are rare, thus limiting the understanding of the manifestations and survival from these tumors. Nomograms are the graphical representation of mathematical relationships or laws that accurately predict individual survival.

METHODS

A total of 1033 patients with spinal and pelvic bone tumors between 2004 and 2016 were selected from the Surveillance, Epidemiology, and End Results (SEER) database. Multivariate Cox analysis was used on the training set to select significant predictors to build a nomogram that predicted 3- and 5-year CSS. We validate the precision of the nomogram by discrimination and calibration, and the clinical value of nomogram was assessed by making use of a decision curve analyses (DCA).

RESULTS

Data from 1033 patients with initially-diagnosed spinal and pelvic tumors were extracted from the SEER database. Multivariate analysis of the training cohort, predictors included in the nomogram were age, pathological type, tumor stage, and surgery. The value of C-index was 0.711 and 0.743 for the internal and external validation sets, respectively, indicating good agreement with actual CSS. The internal and external calibration curves revealed good correlation of CSS between the actual observation and the nomogram. Then, the DCA showed greater net benefits than that of treat-all or treat-none at all time points. A novel risk grouping system was established for CSS that can readily divide all patients into three distinct risk groups.

CONCLUSION

The proposed nomogram obtained more precision prognostic prediction for patients with initially-diagnosed primary spinal and pelvic tumors.

LEVEL OF EVIDENCE

3.

Vertebral Artery Sacrifice versus Skeletonization in the Setting of Cervical Spine Tumor Resection: Case Series

OBJECTIVE

Tumors of the cervical spine often encase 1 or both vertebral arteries (VA), presenting the treating surgeon with the dilemma of whether to sacrifice or skeletonize the artery. We propose an algorithm for VA management in surgeries for cervical neoplasms METHODS: A retrospective review was carried out of 67 patients undergoing resection of cervical spine tumors with VA involvement. Patients were categorized by tumor origin (primary vs. metastatic) and degree of circumferential VA involvement: 1) abutment only; 2) <180° circumferential involvement; 3) >180° circumferential involvement without complete encasement; or 4) complete encasement.

RESULTS

Twelve patients (18%) underwent VA sacrifice, whereas 55 (82%) underwent VA skeletonization. Compared with 11/30 patients with primary tumors (37%), only 1/37 patients (3%) with metastatic disease underwent VA sacrifice (P < 0.01). This patient had invasion of the V2 arterial wall, requiring VA sacrifice. Odds of VA sacrifice also increased with increasing circumferential involvement (P < 0.01). No patients with simple abutment or 0°-180° circumferential involvement underwent sacrifice, whereas 6 of 10 (60%) with 180°-359° involvement and 6 of 29 (21%) with complete encasement underwent VA sacrifice. Of the 27 patients with ≥180° involvement, the reasons for preserving the VA were metastatic disease at the time of treatment (n = 18), a compromised contralateral VA (n = 7), vertebrobasilar junction aplasia (n = 1), and presence of a radiculomedullary artery at the affected level (n = 1).

CONCLUSIONS

Primary tumor disease and >180° of circumferential VA involvement should be considered as indications for intraoperative sacrifice of the VA pending preoperative angiographic evaluation for contraindications.

Surgical strategies for primary malignant tumors of the thoracic and lumbar spine

BACKGROUND

Primary malignant tumors of the thoracic and lumbar spine are rare. They are mainly hematologic malignancies and more rarely sarcomas or chordomas. Giant-cell tumors and osteoblastomas, while benign, are locally very aggressive and their excision should be discussed as an option. Other possibilities are tumors from nearby organs invading the spine, which are actually carcinomas, but may benefit from radical excision in select cases.

METHODS

Excision of these tumors is complex and must be integrated in the diagnostic and therapeutic strategy established by a specific multidisciplinary tumor board at a designated cancer center. Surgical resection must combine tumor excision with long-lasting reconstruction of the spine and neighboring soft tissues. The initial excision must be as complete as possible as the possibilities of repeat excision are nearly impossible if the first resection is not complete.

RESULTS

An exhaustive preoperative imaging workup is essential for determining the tumor's spread and for determining the best surgical strategy. This will often require participation of other surgical specialties, which are well versed in teamwork. Thanks to this multidisciplinary care, especially the participation of thoracic and plastic surgeons, significant progress has been made recently. The first is the possibility of doing very extensive tumor excisions at the spine and in the neighboring organs, thus expanding the surgical indications to patients who were previously considered as being inoperable. We will discuss the surgical strategy and surgical approaches by spine level. Bone and soft tissue reconstruction is more effective thanks to the introduction of new spinal instrumentation and coverage flaps, which have drastically reduced the intra- and postoperative complications. Lastly, the risk factors for neurological complications are better understood, making them easier to prevent and to treat, if they were to occur.

CONCLUSION

These advances have translated to better cancer outcomes, especially better control of the tumor with neoadjuvant therapies (targeted chemotherapy) and preoperative conformal radiotherapy.

Novel prognostication of patients with spinal and pelvic chondrosarcoma using deep survival neural networks

BACKGROUND

We used the Surveillance, Epidemiology, and End Results (SEER) database to develop and validate deep survival neural network machine learning (ML) algorithms to predict survival following a spino-pelvic chondrosarcoma diagnosis.

METHODS

The SEER 18 registries were used to apply the Risk Estimate Distance Survival Neural Network (RED_SNN) in the model. Our model was evaluated at each time window with receiver operating characteristic curves and areas under the curves (AUCs), as was the concordance index (c-index).

RESULTS

The subjects (n = 1088) were separated into training (80%, n = 870) and test sets (20%, n = 218). The training data were randomly sorted into training and validation sets using 5-fold cross validation. The median c-index of the five validation sets was 0.84 (95% confidence interval 0.79-0.87). The median AUC of the five validation subsets was 0.84. This model was evaluated with the previously separated test set. The c-index was 0.82 and the mean AUC of the 30 different time windows was 0.85 (standard deviation 0.02). According to the estimated survival probability (by 62 months), we divided the test group into five subgroups. The survival curves of the subgroups showed statistically significant separation (p < 0.001).

CONCLUSIONS

This study is the first to analyze population-level data using artificial neural network ML algorithms for the role and outcomes of surgical resection and radiation therapy in spino-pelvic chondrosarcoma.

Identifying the Prognosis Factors and Predicting the Survival Probability in Patients with Non-Metastatic Chondrosarcoma from the SEER Database

OBJECTIVE

To identify prognostic factors and establish nomograms for predicting overall survival (OS) and cause specific survival (CSS) of patients with non-metastatic chondrosarcoma.

METHODS

We collected information on patients with non-metastatic chondrosarcoma from the Surveillance, Epidemiology, and End Results (SEER) database between 2005 and 2014, together with data from the First Affiliated Hospital of Zhengzhou University from 2011 to 2016. Variables including patients' baseline demographics (age, race, and gender), tumor characteristics (tumor size and extension, histology subtype, primary site, and American Joint Committee on Cancer [AJCC] stage), therapy (surgery, chemotherapy, and radiotherapy), and socioeconomic status (SES) were extracted for further analysis. OS and CSS were retrieved as our researching endpoints. Patients from the database were regarded as the training set, and univariate analysis, Lasso regression and multivariate analysis as well as the random forest were used to explore the predictors and establish nomograms. To validate nomograms internally and externally, we applied bootstrapped validation internally with the training dataset, while the dataset for external validation was obtained from the First Affiliated Hospital of Zhengzhou University. We estimated the discriminative ability of nomograms based on Cox proportional hazard regression models by means of calibration curves and the concordance index (C-index) of internal and external validation.

RESULTS

After the implementation of exclusion criteria, there were 1267 patients in the training set and 72 patients in the testing set with non-metastatic chondrosarcomas. Age, gender, grade, histological subtype, primary site, surgery, radiation, chemotherapy, being employed/unemployed, tumor size, and tumor extension were significantly associated with prognosis in the univariate analysis. Age, gender, tumor size and extension, primary site, surgery, radiotherapy, chemotherapy, histological grade, and subtype were independent prognostic factors in the Cox models. The C-index of nomograms (internal: OS, 0.787; CSS, 0.821; external: OS, 0.777; CSS, 0.821) were higher than following conventional systems: AJCC sixth (OS, 0.640; CSS, 0.673) and seventh edition (OS, 0.675; CSS, 0.711).

CONCLUSIONS

Age, gender, tumor size and extension, surgery, histological grade, and subtype were independent prognostic factors for both OS and CSS. In addition, we revealed that chondrosarcomas in the trunk, radiotherapy, and chemotherapy were correlated with poor prognosis. Our nomograms based on significant clinicopathologic features can well predict the 3-year and 5-year survival probability of patients with non-metastatic chondrosarcoma and assist oncologists in making accurate survival evaluation.

Prognostic Factors for Survival in Patients with Clear Cell Sarcoma: An Analysis of the Surveillance, Epidemiology, and End Results (SEER) Database

Background

Clear cell sarcoma (CCS) of soft tissue, or malignant melanoma of soft parts, is a rare disease. We aimed to identify prognostic factors linked to patient survival in CCS by analyzing demographic and clinical features using the Surveillance, Epidemiology, and End Results (SEER) database. This study aimed to identify prognostic factors associated with CCS that would be of clinical value.

Material/Methods

We collected data from patients diagnosed with CCS between 1973 and 2009 from the SEER database. The Kaplan-Meier method and Cox regression analysis were performed to identify prognostic factors for patient survival.

Results

A total of 175 patients with CCS were identified from the SEER database. The 5-year survival rate was 62.9%, and the 10-year survival rate was 51.3%. Patients with CCS with local stage, and with tumor size ≤3 cm were more likely to have good survival rates.

Conclusions

The findings from this study showed that the identifiable prognostic factors in patients with CCS were stage and tumor size. Local stage and tumor size ≤3 cm were favorable prognostic factors for patient survival in CCS.

The clincoradiologic spectrum of notochordal derived masses

The notochord is an essential part of human development that regresses with age. Masses derived from notochordal tissue may be encountered during imaging of the neuroaxis. Fortunately, the majority of these are benign and can usually be differentiated by radiological and clinical findings. In this manuscript, we discuss the clinical and radiologic presentation of the four notochordal derived masses and present a brief overview of their management.

Maximizing Sacral Chordoma Resection by Precise 3-Dimensional Tumor Modeling in the Operating Room Using Intraoperative Computed Tomography Registration with Preoperative Magnetic Resonance Imaging Fusion and Intraoperative Neuronavigation: A Case Series

INTRODUCTION

The primary treatment for patients with sacral chordoma is en bloc surgical resection with negative margins, which has been shown to reduce local recurrence and tumor-related morbidity. Here we describe the use of intraoperative neuronavigation using preoperative spine magnetic resonance imaging fused to intraoperative computed tomography (CT) to create 3-dimensional tumor reconstructions in the operating room for intraoperative identification of bone and soft-tissue margins for maximal safe tumor resection.

METHODS

A single-institution retrospective chart review was completed to encompass our experience of 6 consecutive patients who had sacral chordoma resections using our described navigation protocol. We collected data on patient demographics, previous surgeries, radiation therapy, preoperative examination, spinal levels involved, dural involvement, estimated blood loss, surgery time, tissue diagnosis, follow-up, postoperative examination, complications, and recurrence. Primary outcome was en bloc resection with negative margins as planned preoperatively.

RESULTS

Negative surgical margins were achieved in 5 of 5 patients, who were preoperatively planned for en bloc resection with negative margins. The most common levels involved were S4-S5. All patients had a stable or improved neurologic examination after en bloc surgical resection. The average follow-up was 5.4 months ± 84.6 days. No patient had residual or recurrent tumor at last follow-up.

CONCLUSIONS

Magnetic resonance imaging-CT fusion and 3-dimensional reconstruction techniques using an intraoperative CT scanner with image-guided navigation to aid preoperative planning and surgical resection of sacral chordomas are not well represented in the literature. This technique can be used for planning en bloc surgical resections and for more precisely identifying tumor margins intraoperatively.

Prognostic Factors Associated With Bone Lymphoma Primarily Presenting in the Spine

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

To determine the prognostic indicators in patients with bone lymphoma of the spine.

SUMMARY OF BACKGROUND DATA

To date, prognosis for patients with spinal bone lymphoma is based on results from small series. Large population-based observational studies are lacking.

METHODS

The Surveillance, Epidemiology, and End Results Registry was used to identify all patients with bone lymphoma of the spine from 1995 through 2014. Overall survival (OS) and disease-specific survival (DSS) estimates were obtained using the Kaplan-Meier method and compared across groups using log-rank test. Association of survival with variables was assessed using Cox proportional-hazards regression analysis. Nomograms were established and validated by R software.

RESULTS

A total of 1338 patients were identified with bone lymphoma of the spine. The trend of incidence was relative steady from 1995 to 2014. The mean and median age of diagnosis was 62.9 and 66.0 years, respectively. Men constituted a slightly greater proportion (55.5%) of the cohort. The most common subtype of lymphoma was diffuse large B-cell lymphoma (59.8%). The 5- and 10-year OS rates for those patients were 60.6% and 44.7%, respectively. Multivariate analysis revealed that age, sex, marital status, and race were sociodemographic predictors of OS and DSS. Extracompartmental invasion of tumor and stage IV of lymphoma were significantly correlated with poor OS and DSS. Patients without surgery or radiotherapy was linked to a poor OS. Both OS and DSS of patients with spinal bone lymphoma improved in 2005 to 2014 when compared to 1995 to 2004. In addition, pretreatment nomograms to predict 5- and 10-year survival were established.

CONCLUSION

The findings of this study provide population-based estimates of the prognosis for patients with spinal bone lymphoma. Both sociodemographic and clinical factors may have an impact on the outcomes.

LEVEL OF EVIDENCE

4.

Solitary Plasmacytoma of Bone of the Spine: Results From Surveillance, Epidemiology, and End Results (SEER) Registry

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

To determine the prognostic indicators in patients with solitary plasmacytoma of bone (SPB) of the spine.

SUMMARY OF BACKGROUND DATA

Population-level estimates for prognosis among patients with SPB of the spine are still lacking. Sociodemographic and clinical predictors of outcome have not been well characterized.

METHODS

The Surveillance, Epidemiology, and End Results Registry was used to identify all patients with SPB of the spine from 1995 through 2014. Associated population data were used to determine annual incidence and limited-duration prevalence. Overall survival (OS) estimates were obtained using the Kaplan-Meier method and compared across groups using log-rank test. A Cox regression model was used for multivariate analysis of survival. Logistic regression was performed to identify predictors of the progression to multiple myeloma (MM).

RESULTS

The incidence and prevalence of the disease increased during the study period. Spinal SPB most commonly affected older people (>50) with a male preponderance. The median OS were 74.0 months. The 5 and 10-year survival rates for these patients were 56.1% and 36.7%, respectively. On multivariable analyses, older age, and surgery without radiotherapy were correlated with poor survival of patients with spinal SPB. The 3-year probability of progression to MM was 10.1%. Patients aged >70 years were associated with progression to MM. There was no significant association between the methods of surgical resection (radical or local/partial) and OS or progression to MM.

CONCLUSION

The findings of this study provide population-based estimates of the incidence, prevalence and prognosis for patients with SPB of the spine. This analysis indicated that the only identifiable prognostic indicators were older age and surgery without radiotherapy. Moreover, the methods of surgical resection did not influence the OS or progression to MM.

LEVEL OF EVIDENCE

4.

Development and Validation of Nomograms Predicting Overall and Cancer-Specific Survival of Spinal Chondrosarcoma Patients

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

To develop and validate nomograms to predict overall survival (OS) and cancer-specific survival (CSS) of spinal chondrosarcoma patients.

SUMMARY OF BACKGROUND DATA

In this era of personalized medicine, data those are available to predict the survival of spinal chondrosarcoma patients are still limited due to the rarity of the disease. Nomogram, which has been widely used in clinical oncology, could conveniently and precisely predict survival outcome for individual patient.

METHODS

We retrospectively collected 450 spinal chondrosarcoma patients from the Surveillance, Epidemiology, and End Results (SEER) database between 1984 and 2013. Univariate log-rank and multivariate Cox analyses were used to identify independent prognostic factors. These prognostic factors were included in the nomograms, which predict 3- and 5-year OS and CSS rate. The nomograms were bootstrap validated internally and externally.

RESULTS

A total of 450 patients were collected and randomly assigned into the training (n = 225) and validation (n = 225) cohorts. Age, histologic subtype, grade, tumor size, stage, and surgery were identified as independent prognostic factors for OS and CSS (all P < 0.05) and were further incorporated to construct the nomograms. The concordance indices (C-indices) for internal validation of OS and CSS prediction were 0.807 and 0.821, while for external validation of OS and CSS prediction were 0.756 and 0.767. Internal and external calibration plots both revealed an excellent agreement between nomogram prediction and actual survival.

CONCLUSION

Nomograms were developed to predict OS and CSS for spinal chondrosarcoma patients. The nomograms could assist clinicians in making more accurate survival evaluation and identifying patients with high risk of mortality.

LEVEL OF EVIDENCE

4.

Chondrosarcoma of the Osseous Spine Treated by Surgery With or Without Radiotherapy: A Propensity Score Matched and Grade/Stage-stratified Study

STUDY DESIGN

This was a longitudinal cohort study.

OBJECTIVE

The main objective of this study was to investigate the outcomes of surgery with or without radiotherapy during treatment of patients with chondrosarcoma of the osseous spine.

SUMMARY OF BACKGROUND DATA

Chondrosarcoma is a primary spinal malignant tumor; chemotherapy and radiotherapy (RT) are generally unsuccessful, and thus, the main treatment of choice is complete en bloc resection. However, even with complete resection, these patients still have a significant rate of recurrence, morbidity, and mortality. Although there have been reports that the addition of RT to surgery may lead to increased survival and better cancer control, the evidence of the efficacy of RT remains controversial.

MATERIALS AND METHODS

Patients diagnosed with chondrosarcoma who are then treated by surgery alone or surgery+RT were identified and extracted from the SEER (Surveillance, Epidemiology, and End Results) database (1973-2013). Propensity score matched (PSM) analysis was performed to balance patient characteristics between surgery alone and surgery+RT groups. Patients with a different grade and stage were stratified and analyzed.

RESULTS

A total of 778 patients with chondrosarcoma of the osseous spine treated by surgery alone or surgery+RT were extracted from the SEER database. Before PSM, the unadjusted Kaplan-Meier curve and bivariable Cox proportional hazard regression models showed that the surgery alone group had higher chondrosarcoma cancer-specific survival and overall survival than the surgery+RT group (both P<0.001), while the difference was attenuated after PSM. Stratified analysis found that RT was worse for low-grade chondrosarcoma patients and had a better trend for high-grade chondrosarcoma patients.

CONCLUSIONS

The results of our present study suggest that low-grade chondrosarcoma of the osseous spine is resistant to RT, while high-grade chondrosarcoma patients had a better trend with RT.

LEVEL OF EVIDENCE

Level III.

Risk factors for metastasis at presentation with conventional chondrosarcoma: a population-based study

PURPOSE

The aim of the study was to investigate risk factors for metastasis at diagnosis.

METHODS

We collected patients diagnosed with conventional chondrosarcoma between 1983 and 2014 from the Surveillance, Epidemiology, and End Results (SEER) database. Each patient was classified as having metastatic or localized disease. Univariate and multivariate logistic regression analyses were applied to determine which characteristics were risk factors for metastasis at diagnosis.

RESULTS

Two thousand three hundred forty-nine patients were collected and 180 patients had metastasis at presentation. Data on age, gender, primary site, grade, and tumour size were enrolled into the multivariate logistic analysis. Greater age (60 years or older: OR = 1.872, 95% CI, 1.206 to 2.904), axial or craniofacial location (spine: OR = 1.775, 95% CI, 1.188 to 2.651; thoracic cage: OR = 2.034, 95% CI, 1.321 to 3.134; craniofacial bones: OR = 5.507, 95% CI, 3.001 to 10.107), higher grade (grade II: OR = 1.849, 95%CI, 1.181 to 2.895; grade III: OR = 4.016, 95%CI, 2.513 to 6.418), and larger tumour size (size over 10 cm: OR = 7.135, 95%CI, 2.130 to 23.893) were associated with an increased risk of metastasis at presentation.

CONCLUSIONS

Conventional chondrosarcoma patients with greater age, axial or craniofacial tumour location, higher grade, and larger tumor size were more likely to have metastasis at diagnosis.

Surgical approach selection for total spondylectomy for the treatment of giant cell tumors in the lumbar spine: A retrospective analysis of 12 patients from a single center

AIM

To describe the selection of the surgical approach used for total spondylectomy in the treatment of giant cell tumors of the lumbar spine.

METHODS

This retrospective study included 12 patients with giant cell tumors of the lumbar spine who underwent total spondylectomy. The effect of the Weinstein-Boriani-Biagini surgical staging and tumor location on the approach selected was evaluated.

RESULTS

Two tumors were treated using the posterior approach: one located in L1, extending into layers A∼D and involving sectors 2∼6, and the other located in L4, extending into layers B∼D and involving sectors 4∼11. Four tumors (one each located in L1, L2, L3, and L4) were treated by a combined posterior and anterolateral approach as the tumors involved sectors 5∼6 or 7∼8. Six tumors were treated using a combined posterior and anterior approach, two tumors located in L4, extending into layers A∼D and involving sectors 1∼12, and associated with a soft tissue mass extending into layer A and involving sectors 5∼8; and four tumors located in L5. Complications were observed in 9 of the 12 patients.

CONCLUSIONS

A posterior approach is the obvious strategy for tumors located in L1∼L4 and extending into layers B∼D or A and involving sectors 1∼3 or 10∼12. For tumors invading beyond layer A and involving sectors 1∼12, including those with a soft tissue mass extending from layer A, with involvement of sectors 4∼9, a posterior approach combined with an anterolateral or anterior approach is required. For L5 tumors, a combined posterior and anterior approach is needed.

Chondrosarcoma of the Osseous Spine: An Analysis of Epidemiology, Patient Outcomes, and Prognostic Factors Using the SEER Registry From 1973 to 2012

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

To determine the epidemiology and prognostic indicators in patients with chondrosarcoma of the osseous spine.

SUMMARY OF BACKGROUND DATA

Chondrosarcoma of the spine is rare, with limited data on its epidemiology, clinicopathologic features, and treatment outcomes. Therapy centers on complete en bloc resection with radiotherapy reserved for subtotal resection or advanced disease.

METHODS

The Surveillance, Epidemiology, and End Results Registry was queried for patients with chondrosarcoma of the osseous spine from 1973 to 2012. Study variables included age, sex, race, year of diagnosis, size, grade, extent of disease, and treatment modality.

RESULTS

The search identified 973 cases of spinal chondrosarcoma. Mean age at diagnosis was 51.6 years, and 627% of patients were males. Surgical resection and radiotherapy were performed in 75.2% and 21.3% of cases, respectively. Kaplan-Meier analysis demonstrated overall survival (OS) and disease-specific survival (DSS) of 53% and 64%, respectively, at 5 years. Multivariate Cox regression analysis showed that age (OS, P < 0.001; DSS, P = 0.007), grade (OS, P < 0.001; DSS, P < 0.001), surgical resection (OS, P < 0.001; DSS, P < 0.001), and extent of disease (OS, P < 0.001; DSS, P < 0.001) were independent survival determinants; tumor size was an independent predictor of OS (P = 0.006). For confined disease, age (P = 0.013), decade of diagnosis (P = 0.023), and surgery (P = 0.017) were independent determinants of OS. For locally invasive disease, grade (OS, P < 0.001; DSS, P = 0.003), surgery (OS, P = 0.013; DSS, P = 0.046), and size (OS, P = 0.001, DSS, P = 0.002) were independent determinants of OS and DSS. Radiotherapy was an independent indicator of worse OS for both confined (P = 0.004) and locally invasive disease (P = 0.002). For metastatic disease, grade (OS, P = 0.021; DSS, P = 0.012) and surgery (OS, P = 0.007; DSS, P = 0.004) were survival determinants for both OS and DSS, whereas radiotherapy predicted improved OS (P = 0.039).

CONCLUSION

Surgical resection confers survival benefit in patients with chondrosarcoma of the spine independent of extent of disease. Radiotherapy improves survival in patients with metastatic disease and worsens outcomes in patients with confined and locally invasive disease.

LEVEL OF EVIDENCE

4.

Prognostic determinants and treatment outcomes analysis of osteosarcoma and Ewing sarcoma of the spine

BACKGROUND CONTEXT

Osteosarcoma (OGS) and Ewing sarcoma (EWS) are the two classic primary malignant bone tumors. Due to the rarity of these tumors, evidence on demographics, survival determinants, and treatment outcomes for primary disease of the spine are limited and derived from small case series.

PURPOSE

To use population-level data to determine the epidemiology and prognostic indicators in patients with OGS and EWS of the osseous spine.

STUDY DESIGN/SETTING

Large-scale retrospective study.

PATIENT SAMPLE

Patients diagnosed with OGS and EWS of the spine in the Surveillance, Epidemiology, and End Results (SEER) registry from 1973 to 2012.

OUTCOME MEASURES

Overall survival (OS) and disease-specific survival (DSS).

METHODS

Two separate queries of the SEER registry were performed to identify patients with OGS and EWS of the osseous spine from 1973-2012. Study variables included age, sex, race, year of diagnosis, tumor size, extent of disease (EOD), and treatment with surgery and/or radiation therapy. Primary outcome was defined as OS and DSS in months. Univariate survival analysis was performed using the Kaplan-Meier method and the log-rank test. Multivariate analysis was performed using Cox proportional hazards regression models.

RESULTS

The search identified 648 patients with primary OGS and 736 patients with primary EWS of the spine from 1973 to 2012. Mean age at diagnosis was 48.1 and 19.9 years for OGS and EWS, respectively, with OGS showing a bimodal distribution. The median OS and DSS were 1.3 and 1.7 years, respectively, for OGS, with OGS in Paget's disease having worse OS (0.7 years) relative to the mean (log-rank p=.006). The median OS and DSS for EWS were 3.9 and 4.3 years, respectively. Multivariate cox regression analysis showed that age (OS p<.001, DSS p<.001), decade of diagnosis (OS p=.049), surgical resection (OS p<.001, DSS p<.001), and EOD (OS p<.001, DSS p<.001) were independent positive prognostic indicators for spinal OGS; radiation therapy predicted worse OS (hazard ratio [HR] 1.48, confidence interval [CI] 1.05-2.10, p=.027) and DSS (HR 1.74, CI 1.13-2.66, p=.012) for OGS. For EWS, age (OS p<.001, DSS p<.001), surgical resection (OS p=.030, DSS p=.046), tumor size (OS p<.001, DSS p<.001), and EOD (OS p<.001, DSS p<.001) were independent determinants of improved survival; radiation therapy trended toward improved survival but did not achieve statistical significance for both OS (HR 0.76, CI 0.54-1.07, p=.113) and DSS (0.76, CI 0.54, 1.08, p=.126).

CONCLUSIONS

Age, surgical resection, and EOD are key survival determinants for both OGS and EWS of the spine. Radiation therapy may be associated with worse outcomes in patients with OGS, and is of potential benefit in EWS. Overall prognosis has improved in patients with OGS of the spine over the last four decades.