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

Proton Therapy for Spinal Tumors: A Consensus Statement From the Particle Therapy Cooperative Group

PURPOSE

Proton beam therapy (PBT) plays an important role in the management of primary spine tumors. The purpose of this consensus statement was to summarize safe and optimal delivery of PBT for spinal tumors.

METHODS AND MATERIALS

The Particle Therapy Cooperative Group Skull Base/Central nervous system/Sarcoma Subcommittee consisting of radiation oncologists and medical physicists with specific expertise in spinal irradiation developed expert recommendations discussing treatment planning considerations and current approaches in the treatment of primary spinal tumors.

RESULTS

Computed tomography simulation: factors that require significant consideration include (1) patient comfort, (2) setup reproducibility and stability, and (3) accessibility of appropriate beam angles.

SPINE STABILIZATION HARDWARE

If present, hardware should be placed with cross-links well above/below the level of the primary tumor to reduce the metal burden at the level of the tumor bed. New materials that can reduce uncertainties include polyether-ether-ketone and composite polyether-ether-ketone-carbon fiber implants.

FIELD ARRANGEMENT

Appropriate beam selection is required to ensure robust target coverage and organ at risk sparing. Commonly, 2 to 4 treatment fields, typically from posterior and/or posterior-oblique directions, are used.

TREATMENT PLANNING METHODOLOGY

Robust optimization is recommended for all pencil beam scanning plans (the preferred treatment modality) and should consider setup uncertainty (between 3 and 7 mm) and range uncertainty (3%-3.5%). In the presence of metal hardware, use of an increased range uncertainty up to 5% is recommended.

CONCLUSIONS

The Particle Therapy Cooperative Group Skull Base/Central nervous system/Sarcoma Subcommittee has developed recommendations to enable centers to deliver PBT safely and effectively for the management of primary spinal tumors.

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.

The Role of En Bloc Resection in the Modern Era for Primary Spine Tumors

STUDY DESIGN

A literature review.

OBJECTIVE

The aim of this review is to provide an overview of benign and malignant primary spine tumors and a balanced analysis of the benefits and limitations of (and alternatives to) surgical treatment with en bloc resection.

SUMMARY OF BACKGROUND DATA

Primary spine tumors are rare but have the potential to cause severe morbidity, either from the disease itself or as a result of treatment. The prognosis, goals, and treatment options vary significantly with the specific disease entity. Appropriate initial management is critical; inappropriate surgery before definitive treatment can lead to recurrence and may render the patient incurable, as salvage options are often inferior.

METHODS

We performed a comprehensive search of the PubMed database for articles relevant to primary spine neoplasms and en bloc spine surgery. Institutional review board approval was not needed.

RESULTS

Although Enneking-appropriate en bloc surgery can be highly morbid, it often provides the greatest chance for local control and/or patient survival. However, there is growing data to support modern radiotherapy as a feasible and less morbid approach to certain primary neoplasms that historically were considered radioresistant.

CONCLUSIONS

Choosing the optimal approach to primary spine tumors is complex. A comprehensive and up-to-date assessment of the evidence is required to guide patient care and to balance the often-competing goals of prolonging life and preserving quality of life.

The novel dynamic nomogram and risk classification system constructed for predicting post-surgical overall survival and mortality risk in primary chondrosarcoma: a population study based on SEER database

BACKGROUND

Surgery is the predominant method to improve the prognosis of primary chondrosarcoma patients. We aimed to construct the first reliable nomogram to predict the post-surgical overall survival (OS) of primary chondrosarcoma patients.

METHODS

We downloaded all primary chondrosarcoma patients treated with surgery between 2004 and 2015 from the Surveillance, Epidemiology, and End Results (SEER) database, and randomized them into training set (60%) and validation set (40%). Cox proportional regression analysis was applied to the training set to identify independent prognostic variables, and then constructed a nomogram for predicting 3-, 5-, and 8-year OS. The Harrell's concordance index (C-index), receiver operating characteristic curve (ROC), the area under curve (AUC), calibration curve and decision curve analysis (DCA) was used to assess the predictive efficacy and clinical applicability of the nomogram. The nomogram was also compared with The American Joint Committee on Cancer (AJCC) staging system.

RESULTS

A total of 1005 post-surgical primary chondrosarcoma patients were included in this study. We finally identified five independent prognostic variables to construct the nomogram, being age, grade, tumor size, disease stage and histological type. The C-index results showed that the prediction performance of the nomogram was significantly better than the AJCC staging system. In the training set, (C-index: 0.805, 95% CI 0.879-0.730 vs 0.686, 95% CI 0.606-0.766); in the validation set, (C-index: 0.811, 95% CI 0.895-0.727 vs 0.697, 95% CI 0.647-0.799). Additionally, the AUC values generated by the ROC were all greater than 0.8, which also indicated the excellent predictive performance of the nomogram. The calibration curves showed that the predicted survival rate was highly similar to the actual. Time-dependent ROC and DCA showed that the nomogram has better predictive performance and net clinical benefits than the AJCC staging system. Finally, a risk stratification system based on nomogram was constructed.

CONCLUSION

We successfully constructed and validated the first nomogram that could reliably predict 3-, 5-, and 8-year post-surgical OS in primary chondrosarcoma patients. Furthermore, the web-based dynamic nomogram could be more conveniently applied to clinic, providing assistance to surgeons and patients.

Clinical diagnostic and radiographic features of a primary intradural spinal chondrosarcoma in a young adult: illustrative case

BACKGROUND

Mesenchymal chondrosarcoma (MCS) is an aggressive subtype of chondrosarcoma that occurs extremely rarely in the central nervous system. Patients often present with pain or sensorimotor deficits, and resection is considered the gold standard. The role of adjuvant radiation and/or chemotherapy is largely unknown.

OBSERVATIONS

A 22-year-old male presented with a 4-month history of progressive back and bilateral leg pain. He underwent imaging workup with magnetic resonance imaging of the lumbar spine and was found to have an intradural, extramedullary, heterogeneously enhancing mass spanning the L4-5 vertebral levels. Intraoperatively, a lobular, partially calcified mass with a ventral dural attachment displacing the nerve roots laterally was observed. The mass was removed en bloc, and the patient later underwent adjuvant radiotherapy, with no evidence of recurrence 2 years following surgery.

LESSONS

Spinal MCS is extremely rare and often presents with a more aggressive course than conventional chondrosarcoma. Radiological diagnosis is challenging, as the tumor mimics different pathologies. The presence of calcifications, heterogeneous enhancement, and a more rapid clinical course as well as the presence of HEY1::NCOA2 gene fusion, which can be detected by surrogate immunohistochemistry, aids in diagnosis. Resection is the standard of care, and adjuvant radiation may be considered to reduce local recurrence, although further studies are warranted.

Primary Osseous Malignancies of the Spine

Malignant primary vertebral tumours comprise an uncommon group of primary bone malignancies that can pose a diagnostic and therapeutic challenge. The most frequently encountered malignant primary vertebral tumours include chordoma, chondrosarcoma, Ewing sarcoma and osteosarcoma. These tumours often present with nonspecific symptoms, such as back pain, neurologic deficits and spinal instability, which can be confused for the more commonly encountered mechanical back pain and may delay their diagnosis and treatment. Imaging, including radiography, computed tomography (CT) and magnetic resonance imaging (MRI) is crucial for diagnosis, staging, treatment planning and follow-up. Surgical resection remains the mainstay of treatment for malignant primary vertebral tumours, but adjuvant radiotherapy and chemotherapy may be necessary for achieving complete tumour control depending on the type of tumour. In recent years, advances in imaging techniques and surgical approaches, such as en-bloc resection and spinal reconstruction, have improved the outcomes for patients with malignant primary vertebral tumours. However, the management can be complex due to the anatomy involved and the high morbidity and mortality associated with surgery. The different types of malignant primary vertebral lesions will be discussed in this article with an emphasis on the imaging features.

Development and validation of a nomogram for predicting prognosis of high-grade chondrosarcoma: A surveillance, epidemiology, and end results-based population analysis

BACKGROUND

The incidence of chondrosarcoma is increasing every year, and the treatment and prognosis of patients with high-grade chondrosarcoma are becoming more and more important. Nomogram is a tool that can quickly and easily predict the overall survival of tumor patients. Therefore, the development and validation of a nomogram to predict overall survival in patients with high-grade chondrosarcoma was desired.

METHODS

We retrospectively collected 396 patients with high-grade chondrosarcoma from the Surveillance, Epidemiology, and End Results (SEER) database from 2004 to 2015. Randomly divided into model and validation groups, the best cut-off values for age and tumor size grouping were derived by using X-tile software. Then, independent prognostic factors for high-grade chondrosarcoma were derived by SPSS.26 univariate and multivariate Cox analyses analysis in the model group, and the model was evaluated by using R software, using C-indix and ROC curves, and finally these independent prognostic factors were included in Nomogram.

RESULTS

396 patients were randomly assigned to the modelling group (n = 280) or the validation group (n = 116). Age, tissue-type, tumor size, AJCC stage, regional expansion and surgery were identified as independent prognostic factors (p < 0.05) which further combined to construct a nomogram. The C-index of internal validation for overall survival(OS) was 0.757, while the C-index of external validation for overall survival(OS) was 0.832. Both internal and external calibration curves show a good agreement between nomogram prediction and actual survival.

CONCLUSION

In this study, we established age, tumour size, AJCC stage, tissue type, surgery and tumor extension as independent prognostic factors for high-grade chondrosarcoma and constructed a nomogram to predict 3- and 5-year survival rates for high-grade chondrosarcoma.

Is the Number of National Database Research Studies in Musculoskeletal Sarcoma Increasing, and Are These Studies Reliable?

BACKGROUND

Large national databases have become a common source of information on patterns of cancer care in the United States, particularly for low-incidence diseases such as sarcoma. Although aggregating information from many hospitals can achieve statistical power, this may come at a cost when complex variables must be abstracted from the medical record. There is a current lack of understanding of the frequency of use of the Surveillance, Epidemiology, and End Results (SEER) database and the National Cancer Database (NCDB) over the last two decades in musculoskeletal sarcoma research and whether their use tends to produce papers with conflicting findings.

QUESTIONS/PURPOSES

(1) Is the number of published studies using the SEER and NCDB databases in musculoskeletal sarcoma research increasing over time? (2) What are the author, journal, and content characteristics of these studies? (3) Do studies using the SEER and the NCDB databases for similar diagnoses and study questions report concordant or discordant key findings? (4) Are the administrative data reported by our institution to the SEER and the NCDB databases concordant with the data in our longitudinally maintained, physician-run orthopaedic oncology dataset?

METHODS

To answer our first three questions, PubMed was searched from 2001 through 2020 for all studies using the SEER or the NCDB databases to evaluate sarcoma. Studies were excluded from the review if they did not use these databases or studied anatomic locations other than the extremities, nonretroperitoneal pelvis, trunk, chest wall, or spine. To answer our first question, the number of SEER and NCDB studies were counted by year. The publication rate over the 20-year span was assessed with simple linear regression modeling. The difference in the mean number of studies between 5-year intervals (2001-2005, 2006-2010, 2011-2015, 2016-2020) was also assessed with Student t-tests. To answer our second question, we recorded and summarized descriptive data regarding author, journal, and content for these studies. To answer our third question, we grouped all studies by diagnosis, and then identified studies that shared the same diagnosis and a similar major study question with at least one other study. We then categorized study questions (and their associated studies) as having concordant findings, discordant findings, or mixed findings. Proportions of studies with concordant, discordant, or mixed findings were compared. To answer our fourth question, a coding audit was performed assessing the concordance of nationally reported administrative data from our institution with data from our longitudinally maintained, physician-run orthopaedic oncology dataset in a series of patients during the past 3 years. Our orthopaedic oncology dataset is maintained on a weekly basis by the senior author who manually records data directly from the medical record and sarcoma tumor board consensus notes; this dataset served as the gold standard for data comparison. We compared date of birth, surgery date, margin status, tumor size, clinical stage, and adjuvant treatment.

RESULTS

The number of musculoskeletal sarcoma studies using the SEER and the NCDB databases has steadily increased over time in a linear regression model (β = 2.51; p < 0.001). The mean number of studies per year more than tripled during 2016-2020 compared with 2011-2015 (39 versus 13 studies; mean difference 26 ± 11; p = 0.03). Of the 299 studies in total, 56% (168 of 299) have been published since 2018. Nineteen institutions published more than five studies, and the most studies from one institution was 13. Orthopaedic surgeons authored 35% (104 of 299) of studies, and medical oncology journals published 44% (130 of 299). Of the 94 studies (31% of total [94 of 299]) that shared a major study question with at least one other study, 35% (33 of 94) reported discordant key findings, 29% (27 of 94) reported mixed key findings, and 44% (41 of 94) reported concordant key findings. Both concordant and discordant groups included papers on prognostic factors, demographic factors, and treatment strategies. When we compared nationally reported administrative data from our institution with our orthopaedic oncology dataset, we found clinically important discrepancies in adjuvant treatment (19% [15 of 77]), tumor size (21% [16 of 77]), surgery date (23% [18 of 77]), surgical margins (38% [29 of 77]), and clinical stage (77% [59 of 77]).

CONCLUSION

Appropriate use of databases in musculoskeletal cancer research is essential to promote clear interpretation of findings, as almost two-thirds of studies we evaluated that asked similar study questions produced discordant or mixed key findings. Readers should be mindful of the differences in what each database seeks to convey because asking the same questions of different databases may result in different answers depending on what information each database captures. Likewise, differences in how studies determine which patients to include or exclude, how they handle missing data, and what they choose to emphasize may result in different messages getting drawn from large-database studies. Still, given the rarity and heterogeneity of sarcomas, these databases remain particularly useful in musculoskeletal cancer research for nationwide incidence estimations, risk factor/prognostic factor assessment, patient demographic and hospital-level variable assessment, patterns of care over time, and hypothesis generation for future prospective studies.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Malignant Brain and Spinal Tumors Originating from Bone or Cartilage

Malignant bone tumors affecting the brain and spine are a rare and exceedingly difficult-to-treat group of diseases. Most commonly consisting of chordoma and chondrosarcoma, these tumors also include giant-cell tumors and osteosarcomas. This chapter will cover the background, epidemiology, genetics, molecular biology, histopathology, radiographic features, clinical manifestations, therapeutic approaches, and clinical management of each entity.

A Simple-to-Use Nomogram for Predicting Postoperative Early Death Risk in Elderly Patients with Spinal Tumors: A Population-Based Study

Background

For elderly patients with primary spinal tumors, surgery is the best option for many elderly patients, in addition to palliative care. However, due to the unique physical function of elderly patients, the short-term prognosis is often unpredictable. It is therefore essential to develop a novel nomogram as a clinical aid to predict the risk of early death for elderly patients with primary spinal tumors who undergo surgery.

Materials and Methods

In this study, clinical data were obtained from 651 patients through the SEER database, and they were retrospectively analyzed. Logistic regression analyses were used for risk-factor screening. Predictive modeling was performed through the R language. The prediction models were calibrated as well as evaluated for accuracy in the validation cohort. The receiver operating characteristic (ROC) curve and the decision curve analysis (DCA) were used to evaluate the functionality of the nomogram.

Results

We identified four separate risk factors for constructing nomograms. The area under the receiver operating characteristic curve (training set 0.815, validation set 0.815) shows that the nomogram has good discrimination ability. The decision curve analysis demonstrates the clinical use of this nomogram. The calibration curve indicates that this nomogram has high accuracy. At the same time, we have also developed a web version of the online nomogram for clinical practitioners to apply.

Conclusions

We have successfully developed a nomogram that can accurately predict the risk of early death of elderly patients with primary spinal tumors undergoing surgery, which can provide a reference for clinicians.

Influence of marital status on the treatment and survival of middle-aged and elderly patients with primary bone cancer

Objective

The role of spousal support has been recognized to benefit patients with many chronic diseases and cancers. However, the impact of marital status on the survival of middle-aged and elderly patients with primary bone tumors remains elusive.

Materials and methods

The data of patients aged ≥ 45 years with primary bone tumors diagnosed between 2000 and 2018 were extracted from the Surveillance, Epidemiology, and End Results Database. Kaplan–Meier analysis was used to assess the overall survival and tumor-specific survival of patients. The Cox proportional hazards and Fine-and-Gray models were used to calculate the hazard ratios (HRs) and sub-distribution HRs (sHR) and the corresponding 95% confidence interval (CI) of all-cause mortality and tumor-specific mortality, respectively.

Results

A total of 5,640 primary bone tumors were included in the study. In 45–59 years cohort, married, unmarried, divorced and widowed accounted for 66.0, 21.0, 11.2, and 1.8%, respectively; while 64.3, 10.1, 8.8, and 16.8% in 60+ years cohort, respectively. The widowed patients had a lower proportion of early-stage tumors at diagnosis than that married, unmarried, and divorced patients (31.0% vs. 36% vs. 37.1% vs. 39.4%; P = 0.008), and had a higher proportion of patients who did not undergo surgery than that of married, unmarried, and divorced patients (38.6% vs. 21.3% vs. 24.6% vs. 24.4%; P &lt; 0.001). The widowed population had an increased risk of all-cause mortality (HR, 1.68; 95% CI, 1.50–1.88; P &lt; 0.001) and disease-related mortality (HR, 1.33; 95% CI, 1.09–1.61; P = 0.005) compared with the married population.

Conclusion

The marital status of middle-aged and elderly people can affect the tumor stage at diagnosis, treatment, and survival prognosis of patients with primary bone cancer. Widowed patients are more inclined to choose non-surgical treatment and have the worst prognosis.

The clinicopathological characteristics and prognosis of young patients with chondrosarcoma of bone

Purpose

Clinicopathologic characteristics and treatment outcomes for young patients (less than 40 years) with chondrosarcoma of bone are rarely documented. The purpose of this study is to determine the clinicopathological characteristics and identify the survival predictors for this rare population.

Patients and Methods

We used the Surveillance, Epidemiology, and End Results (SEER) database to identify young patients with chondrosarcoma of bone between 1973 and 2016. Univariate and multivariate Cox regression analyses were conducted to determine the independent risk factors. Kaplan-Meier method was used to intuitively show the survival difference stratified by different treatments.

Results

A total of 1312 eligible young patients with chondrosarcoma of bone were analyzed this study. The mean age at diagnosis was 28.5 ± 0.2 years old (ranging from 1 to 40 years). 51.1% of cases were located in the extremity. More than two-thirds of patients (71.4%) were high grade. The majority of the patients (92.0%) received surgery, only 11.8% of patients received radiotherapy, and only 10.4% of patients received chemotherapy. The 5-year overall survival (OS) and cancer-specific survival (CSS) rates of this cohort were 88.5% and 89.1%, respectively. According to the results of multivariate analysis, nine variables were significantly correlated with OS and CSS, including gender, year of diagnosis, tumor site, tumor grade, tumor subtype, distant metastasis, tumor size, surgery, and chemotherapy.

Conclusion

Young patients with chondrosarcoma of bone experienced better prognosis. Surgery was significantly correlated with increased survival, while chemotherapy was significantly correlated with decreased survival. Radiotherapy was not a meaningful survival predictor of young patients with chondrosarcoma of bone. Prospective clinical trials are needed in the future to determine the effect of radiotherapy and chemotherapy on prognosis of those patients.

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.

Chondrosarcoma patient characteristics, management, and outcomes based on over 5,000 cases from the National Cancer Database (NCDB)

INTRODUCTION

Chondrosarcoma, although relatively uncommon, represents a significant percentage of primary osseous tumors. Nonetheless, there are few large-cohort, longitudinal studies of long-term survival and treatment outcomes of chondrosarcoma patients and none using the National Cancer Database (NCDB).

METHODS

Chondrosarcoma patients were identified from the 2004-2015 NCDB datasets and divided on three primary tumor sites: appendicular, axial, and other. Demographic, treatment, and long-term survival data were determined for each group. Multivariate Cox analysis and Kaplan-Meier survival curves were generated to assess long-term survival over time for each.

RESULTS

In total, 5,329 chondrosarcoma patients were identified, of which 2,686 were appendicular and 1,616 were axial. Survival was higher among the appendicular cohort than axial at 1-year, 5-year, and 10-year (89.52%, 75.76%, and 65.24%, respectively). Multivariate Cox analysis identified patients in the appendicular cohort to have significantly greater likelihood of death with increasing age category, distant metastases at presentation, and male sex (p<0.001 for each). Best outcomes for seen for those undergoing surgical treatment (p<0.001). Patients in the axial cohort were with increased likelihood of death with increasing age category and distant metastases (p<0.001), while surgical treatment with or without radiation were associated with a significant decrease (p<0.001). Kaplan-Meier survival analysis showed worst survival for the axial cohort (p<0.001) and patients with distant metastases at presentation (p<0.001). Survival was not significantly different between older (2004-2007) and more recent years (2012-2016) (p = 0.742).

CONCLUSIONS

For both appendicular and axial chondrosarcomas, surgical treatment remains the mainstay of treatment due to its continued superiority for the long-term survival of patients, although advancements in survival over the last decade have been insignificant. Presence of distant metastases and axial involvement are significant, poor prognostic factors perhaps because of difficulty in surgical excision or extent of disease.

Dynamic Predictive Models With Visualized Machine Learning for Assessing Chondrosarcoma Overall Survival

Chondrosarcoma is a malignant bone tumor with a low incidence rate. Accurate risk evaluation is crucial for chondrosarcoma treatment. Due to the limited reliability of existing predictive models, we intended to develop a credible predictor for clinical chondrosarcoma based on the Surveillance, Epidemiology, and End Results data and four Chinese medical institutes. Three algorithms (Best Subset Regression, Univariate and Cox regression, and Least Absolute Shrinkage and Selector Operator) were used for the joint training. A nomogram predictor including eight variables—age, sex, grade, T, N, M, surgery, and chemotherapy—is constructed. The predictor provides good performance in discrimination and calibration, with area under the curve ≥0.8 in the receiver operating characteristic curves of both internal and external validations. The predictor especially had very good clinical utility in terms of net benefit to patients at the 3- and 5-year points in both North America and China. A convenient web calculator based on the prediction model is available at https://drwenle029.shinyapps.io/CHSSapp, which is free and open to all clinicians.

A Radiologists' Guide to En Bloc Resection of Primary Tumors in the Spine: What Does the Surgeon Want to Know?

En bloc resection in the spine is performed for both primary and metastatic bone lesions and has been proven to lengthen disease-free survival and decrease the likelihood of local recurrence. It is a complex procedure, which requires a thorough multi-disciplinary approach. This article will discuss the role of the radiologist in characterizing the underlying tumor pathology, staging the tumor and helping to predict possible intraoperative challenges for en bloc resection of primary bone lesions. The postoperative appearances and complications following en bloc resection in the spine will be considered in subsequent articles.

Effect of surgery and radiotherapy on overall survival in patients with chondrosarcoma: A SEER-based study

PURPOSE

Chondrosarcoma is an orthopedic malignancy, and the purpose of this study was to evaluate the effect of surgery and radiotherapy (RT) on the survival of patients with chondrosarcoma.

METHODS

Data were obtained from the SEER database for patients diagnosed with chondrosarcoma between 1988 and 2015. All patients were divided into surgery, RT, surgery + RT, and no surgery/no RT groups. Kaplan-Meier curves were used to analyze the overall survival and cancer-specific survival of patients in different treatment groups. The propensity score matching was used to balance baseline covariates between patients in the surgery and surgery + RT groups and in the RT and surgery + RT groups.

RESULTS

Data from 3756 patients with chondrosarcoma were included in this study. The number of patients who underwent surgery, RT, surgery + RT, and no surgery or RT was 2885 (76.8%), 112 (3.0%), 403 (10.7%), and 356 (9.5%), respectively. Multivariate Cox regression models showed that treatment modality was independent risk factor for OS and CSS. Before PSM, Kaplan-Meier curves showed that OS and CSS were highest in the surgery group and lowest in the RT group. After PSM, although there was no significant difference in OS (p = .13) and CSS (p = .22) between the surgery and surgery + RT group, OS was longer in the surgery group than in the surgery + RT group. Additionally, OS (p < .001) and CSS (p = .009) were longer in the surgery + RT group than in the RT group after PSM.

CONCLUSION

Surgical resection was the key approach for the treatment of chondrosarcoma, while RT confers no significant advantage in improving patient survival time.

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.

Primary osseous chondrosarcoma in the lumbar spine: case report and literature review with analysis

Primary spinal chondrosarcoma (CS) is rare. Only a few previous case reports have included a detailed description of the surgical process used to treat the CS. In addition, a paucity of documentation exists comparing differences in the outcomes between the approaches in en bloc resection. Here, we present a case of CS in the lumbar (L) spine treated with two-stage (anterior and posterior approach) en bloc surgery and analyze the differences between one-stage and two-stage approaches in the treatment of primary lumbar CS. A 30-year-old male patient with an L3 vertebral body CS presented with back pain and lower limb weakness. Lumbar spine magnetic resonance imaging (MRI) showed an L3 vertebral body tumor with cord and root compression. Two-stage surgery comprising posterior total laminectomy and transpedicular screw fixation over L2–L4 in the first stage, with subsequent anterior corpectomy, cage implantation, and anterior lumbar interbody fusion was performed to achieve total tumor removal and stabilization. The patient’s symptoms improved postoperatively, with no recurrence as of the 2-year follow-up. The analysis of previous similar cases showed that two-stage surgery, compared with one-stage surgery, appears to be beneficial in lumbar spine multisegment disease, providing a lower recurrence rate.

Nerve Root Sparing En Bloc Resection of Sacral Chondrosarcoma: Technical Note and Review of the Literature

BACKGROUND

Total en bloc sacrectomy provides the best long-term local control for large primary bony sacral tumors, but often requires lumbosacral nerve root sacrifice leading to loss of ambulation and/or bowel, bladder, and/or sexual dysfunction. Nerve-sparing techniques may be an option for some patients that avoid these outcomes and accordingly improve postoperative quality of life.

OBJECTIVE

To describe the technique for a posterior-only en bloc hemisacrectomy with maximal nerve root preservation and to summarize the available literature.

METHODS

A 38-yr-old woman with a 7.7 × 5.4 × 4.5 cm biopsy-proven grade 2 chondrosarcoma involving the left L5-S2 posterior elements underwent a posterior-only left hemisacrectomy tri-rod L3-pelvis fusion. A systematic review of the English literature was also conducted to identify other descriptions of high sacrectomy with distal sacral nerve root preservation.

RESULTS

Computer-aided navigation facilitated an extracapsular resection that allowed preservation of the left-sided L5 and S3-Co roots. Negative margins were achieved and postoperatively the patient retained ambulation and good bowel/bladder function. Imaging at 9-mo follow-up showed no evidence of recurrence. The systematic review identified 4 prior publications describing 6 total patients who underwent nerve-sparing sacral resection. Enneking-appropriate resection was only obtained in 1 case though.

CONCLUSION

Here we describe a technique for distal sacral nerve root preservation during en bloc hemisacrectomy for a primary sacral tumor. Few prior descriptions exist, and the present technique may help to reduce the neurological morbidity of sacral tumor surgery.

Refractory recurrent spinal chondrosarcoma: What is the role of salvage surgery?

BACKGROUND

The spinal chondrosarcoma has high risk of recurrence if the initial surgery is not performed in an en bloc fashion. It remains technically demanding to surgically manage the refractory recurrent spinal chondrosarcoma (RRSC). This study is to assess the clinical features and investigate the prognostic factors for patients with RRSCs.

METHODS

forty-nine patients with RRSCs underwent salvage surgeries in our institution, and the clinical characteristics were collected and recorded by two independent reviewers. Univariate and multivariate analyses were performed to investigate the independent prognostic factors of recurrence-free survival (RFS) and overall survival (OS) for patients with RRSCs.

RESULTS

During the mean follow-up of 31.7 ± 21.04 months (Range 9-93), the 3-year RFS and OS rate was 24.5% and 34.5%, respectively. According to the Cox proportional hazards regression model, wide excision with tumor-free margin (>4 mm) was associated with both better RFS and OS for patients with RRSCs. Meanwhile, the number of recurrences ≤2 was beneficial to RFS, while high pathological grade was correlated with worse OS.

CONCLUSIONS

Wide excision with tumor-free margin (>4 mm) is recommendable if appropriate in the salvage surgery for patients with RRSCs. Patients with number of recurrences ≤ 2 and lower pathological grade may have better RFS and OS, respectively.

Primary mobile vertebral column sarcomas: Prognostic factors vary by histologic subtypes

BACKGROUND

Primary sarcomas originating from the mobile spine portends a particularly sinister outcome. Rarity of the disease process has resulted in inconsistent data due to small sample size and heterogeneity in patient selection and analytics.

METHODS

Surveillance, Epidemiology and End Result (SEER) database from 1975 to 2017 was queried to report incidence and survival data in 712 patients in the United States. Kaplan-Meier and Cox Regression were used to determine the prognostic factors affecting survival.

RESULTS

Incidence of spinal sarcoma was 0.019 per 100,000 persons in 2017 and has not significantly changed since 2000 (p > 0.05). Disease-specific 5-year survival for the entire cohort was 57%. Osteosarcoma has the worst 5-year survival (39%) and chondrosarcoma has the best 5-year survival (69%). Independent predictors of survival for the entire cohort included age, grade, and stage. Stage was an independent predictor of survival for every histologic subtype. Additional predictors of survival for spinal osteosarcoma, Ewing sarcoma, and chondrosarcoma included age, size, and grade, respectively.

CONCLUSIONS

The current study is an analysis of a population-based registry reporting incidence survival data for patients with sarcoma of mobile vertebral column. Survival and prognostic factors vary by histologic subtypes. There is lack of improvement in survival over the last three decades.

Systematic review of charged-particle therapy for chordomas and sarcomas of the mobile spine and sacrum

OBJECTIVE

Long-term local control in patients with primary chordoma and sarcoma of the spine and sacrum is increasingly reliant upon en bloc resection with negative margins. At many institutions, adjuvant radiation is recommended; definitive radiation is also recommended for the treatment of unresectable tumors. Because of the high off-target radiation toxicities associated with conventional radiotherapy, there has been growing interest in the use of proton and heavy-ion therapies. The aim of this study was to systematically review the literature regarding these therapies.

METHODS

The PubMed, OVID, Embase, and Web of Science databases were queried for articles describing the use of proton, combined proton/photon, or heavy-ion therapies for adjuvant or definitive radiotherapy in patients with primary sarcoma or chordoma of the mobile spine and sacrum. A qualitative synthesis of the results was performed, focusing on overall survival (OS), progression-free survival (PFS), disease-free survival (DFS), and disease-specific survival (DSS); local control; and postradiation toxicities.

RESULTS

Of 595 unique articles, 64 underwent full-text screening and 38 were included in the final synthesis. All studies were level III or IV evidence with a high risk of bias; there was also significant overlap in the reported populations, with six centers accounting for roughly three-fourths of all reports. Five-year therapy outcomes were as follows: proton-only therapies, OS 67%-82%, PFS 31%-57%, and DFS 52%-62%; metastases occurred in 17%-18% and acute toxicities in 3%-100% of cases; combined proton/photon therapy, local control 62%-85%, OS 78%-87%, PFS 90%, and DFS 61%-72%; metastases occurred in 12%-14% and acute toxicities in 84%-100% of cases; and carbon ion therapy, local control 53%-100%, OS 52%-86%, PFS (only reported for 3 years) 48%-76%, and DFS 50%-53%; metastases occurred in 2%-39% and acute toxicities in 26%-48%. There were no studies directly comparing outcomes between photon and charged-particle therapies or comparing outcomes between radiation and surgical groups.

CONCLUSIONS

The current evidence for charged-particle therapies in the management of sarcomas of the spine and sacrum is limited. Preliminary evidence suggests that with these therapies local control and OS at 5 years are comparable among various charged-particle options and may be similar between those treated with definitive charged-particle therapy and historical surgical cohorts. Further research directly comparing charged-particle and photon-based therapies is necessary.

Incidence, Management, and Outcomes of Adult Patients with Spinal Chondrosarcoma in the United States

OBJECTIVE

Spinal chondrosarcomas are rare primary malignant neoplasms composed of cartilage-producing cells. They are slow-growing but locally aggressive lesions that have high rates of recurrence and progression after treatment. We provide the largest comprehensive analysis of prognostic factors, treatment modalities, and survival outcomes in patients with spinal chondrosarcoma using a large, prospectively collected national database.

METHODS

Patients with diagnosis codes specific for chondrosarcoma of the spine, sacrum, and coccyx were queried from the National Cancer Database (NCDB) during 2004-2016. Outcomes were investigated using Cox univariate and multivariate regression analyses, and survival curves were generated for comparative visualization.

RESULTS

A total of 1843 individuals were identified with a diagnosis of chondrosarcoma, 82.1% of which were at the sacrum or coccyx and 17.9% at the spine. The mean overall survival of patients in our cohort was 7.91 years. Increased age, larger tumor, dedifferentiated histology, and presence of metastases were associated with worsened overall survival. Regarding management, 77.7% of patients received surgical intervention and both partial and radical resection were associated with significantly improved overall survival (P < 0.001). Neither radiotherapy nor chemotherapy administration improved overall survival; however, among patients who received radiation, those who received higher-dose radiation had significantly improved overall survival compared with those who received lower-dose radiation.

CONCLUSIONS

Surgical resection significantly improves overall survival in patients with spinal chondrosarcoma. In those patients receiving radiation, those who receive high doses have improved overall survival compared with those who receive lower doses. Further studies into optimal radiation modality and doses are required.

Primary Tumor Resection Prolongs Survival in Spinal Chondrosarcoma Patients With Distant Metastasis

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

To investigate (1) whether resection of primary tumor improves survival of metastatic spinal chondrosarcoma patients and (2) which subgroups of metastatic spinal chondrosarcoma patients benefit more from primary tumor resection.

SUMMARY OF BACKGROUND DATA

Surgical resection is the mainstay of treatment for spinal chondrosarcoma, as chondrosarcoma is inherently resistant to radiotherapy and chemotherapy. However, evidence which justifies resection of the primary tumor for patients with metastatic spinal chondrosarcoma is still lacking.

METHODS

We retrospectively included 110 patients with metastatic spinal chondrosarcoma in the Surveillance, Epidemiology, and End Results database from 1983 to 2016. The association between primary tumor resection and survival was evaluated using Kaplan-Meier analyses, log-rank tests, and multivariable Cox analyses. The effect of primary tumor resection on survival was further assessed in subgroups stratified by histologic subtype, tumor grade, and age.

RESULTS

Overall, 110 patients were divided into surgery group (n = 55, 50%) and nonsurgery group (n = 55, 50%). Primary tumor resection was associated with both prolonged overall survival (hazard ratio 0.262, 95% confidence interval 0.149-0.462, P < 0.001) and cancer-specific survival (hazard ratio 0.228, 95% confidence interval 0.127-0.409, P < 0.001). When we focused on surgical effects in subgroups, primary tumor resection conferred survival advantage on patients with conventional subtype, grade I to III malignancy, and an age younger than 70 years old (P < 0.001 for overall and cancer-specific survival). However, primary tumor resection brought limited survival benefit for patients with dedifferentiated subtype and patients over 70 years old.

CONCLUSION

The present population-based study for the first time reports a clear association between primary tumor resection and prolonged survival in metastatic spinal chondrosarcoma patients. Specifically, primary tumor resection was associated with improved survival in patients with conventional subtype, grade I to III malignancy, and an age younger than 70 years old.

LEVEL OF EVIDENCE

4.

Customized "Whole-Cervical-Vertebral-Body" Reconstruction After Modified Subtotal Spondylectomy of C2-C7 Spinal Tumor Via Piezoelectric Surgery

BACKGROUND

Radical resection is the first-line option in managing cervical primary chondrosarcoma. Favorable anterior reconstruction is challenging after multilevel total spondylectomy in the cervical spine.

OBJECTIVE

To illustrate the application of piezoelectric surgery and three-dimensional (3D) printing techniques in spine surgery.

METHODS

A 27-yr-old patient was referred to our center with complaints of nocturnal neck pain and right upper extremity weakness. A 2-stage radical tumor resection was conducted using piezoelectric surgery with pathologically tumor-free margins. A 3D-printed titanium microporous prosthesis (3D-PTMP) was designed to reconstruct the anterior column of the cervical spine between C1 and T1 for stability.

RESULTS

The whole intraoperative blood loss was 2300 mL over the 2 procedures. The patient had an uneventful recovery, regaining ambulatory status 3 wk after the 2 operations without ventilator support or other severe complications. By the final 14-mo follow-up, the patient had achieved marked pain relief and favorable neurological improvement; a postoperative computed tomography scan indicated a good position of the 3D-printed construct between the endplates with no sign of tumor recurrence or implant subsidence.

CONCLUSION

The applications of piezosurgery in total spondylectomy and in 3D-PTMP in reconstruction can be a favorable alternative for managing multilevel cervical spinal tumors. Further studies are warranted to validate this surgical strategy.

A Clinical Model of Bone Angiosarcoma Patients: A Population-based Analysis of Epidemiology, Prognosis, and Treatment

Objective

To investigate the epidemiological data, prognostic factors, and treatment outcomes of bone angiosarcoma (BA).

Methods

This retrospective study was based on the Surveillance, Epidemiology, and End Results (SEER) database. The medical records of BA patients were selected from the SEER database from 1975 to 2016. Variables including patients' baseline demographics (age, sex, marital status, and year of diagnosis), tumor characteristics (tumor size, grade, and SEER Historic Stage A), and treatment (surgery and radiotherapy) were selected for further analysis. The research endpoints were overall survival (OS) and cancer‐specific survival (CSS). The optimal cutoff values of continuous variables including age, year of diagnosis, and tumor size were identified using the X‐tail program. Univariate Cox regression was used to identify potential prognostic factors and multivariate Cox regression was used to identify independent prognostic factors. All prognostic factors were included to predict the survival time compared to the median OS and CSS times via the novel nomograms. To validate the internal validation of nomograms, we analyzed the concordance indices (C‐index).

Results

This study enrolled a total of 271 patients with malignant vascular bone tumors among residents of the United States between 1975 and 2016. After applying the exclusion criteria (one case without active follow‐up), this study included 152 patients with BA. The median survival time of BA was significantly shorter than that of malignant vascular bone tumors for OS (9 months vs 27 months, P < 0.001). Age, year of diagnosis, tumor size, grade, stage, and surgery were identified as potential prognostic factors for OS or CSS in univariate Cox regression. However, only age (P < 0.001, P < 0.001), stage (P = 0.002, P < 0.001), and surgery (P = 0.001, P = 0.002) were independent prognostic factors for CSS and OS, respectively, in the multivariate analysis. Younger patients less than 54 years have significantly better prognosis for CSS/OS than patients between 54 and 67 years (Hazard ratios [HRs]: 1.651 [1.763–3.575], 2.557 [1.395–4.687]) and more than 67 years (HRs: 4.404 [2.237–8.670], 5.113 [2.923–8.942]). For CSS/OS, the survival time of patients with localized stage was significantly longer than that of patients with regional stage (HRs: 1.530 [0.725–3.228], 1.548 [0.834–2.873]) and that of patients with distant stage (HRs: 1.706 [0.899–3.237], 2.101 [1.254–3.520]). Patients with surgery had more survival time than patients without surgery for CSS/OS (HRs: 2.861 [1.542–5.310], 2.103 [1.308–3.379]). All factors were further included to generate nomograms for CSS and OS. The C‐indexes for the internal validation of OS and CSS prediction were 0.787 (95% confidence interval [CI]: 0.738–0.836) and 0.768 (95% CI: 0.717–0.819), respectively.

Conclusions

Age, stage, and surgery were closely associated with prognosis in patients with BA, and this clinical model was a favorable tool to evaluate survival possibilities.

Conditional Survival Analysis for Spinal Chondrosarcoma Patients After Surgical Resection

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

To evaluate conditional survival after surgical resection for spinal chondrosarcoma patients.

SUMMARY OF BACKGROUND DATA

Survival estimates are usually reported as survival from the time of surgery, but survival probabilities can change over time. Conditional survival, which is a measure of prognosis for patients who have survived a defined period of time, may be more clinically precise and relevant. However, data on conditional survival for spinal chondrosarcoma patients after surgical resection are still lacking.

METHODS

We used the Surveillance, Epidemiology, and End Results (SEER) database to identify 436 spinal chondrosarcoma patients who underwent surgical resection from 1994 and 2013. Kaplan-Meier analyses and Cox regression modeling were performed to evaluate prognostic factors associated with overall survival. Five-year conditional survival (i.e., probability of surviving an additional 5 years, given that a patient has already survived x years) was calculated as 5-CS(x) = OS(x+5)/OS(x). The effect of prognostic factors on conditional survival was also explored.

RESULTS

Four hundred thirty six patients were included in the study cohort. Overall, 1-, 3-, and 5-year overall survival were 92.8%, 79.1%, and 70.3%, respectively. Five-year conditional survival at 1, 3, and 5 years after surgery were 72.9%, 79.0%, and 87.5%. The overall survival rates were lower in cases of age more than or equal to 60 years, male patient, dedifferentiated subtype, Grade III tumor, tumor size more than or equal to 10 cm, distant metastasis, and radiotherapy. Conditional survival improved over time in each subgroup divided by age, sex, race, year of diagnosis, grade, tumor size, extent of disease (EOD), and radiotherapy. In addition, patients with the least favorable prognosis at baseline experienced the greatest increase in 5-year conditional survival over time (e.g., Grade I/II: 78.0%-89.7%, Δ11.7% vs. Grade III: 36.5%-66.6%, Δ30.1%; Localized/Regional: 72.9%-88.1%, Δ15.2% vs. Distant: 43.5%-74.1%, Δ30.6%).

CONCLUSION

Conditional survival for spinal chondrosarcoma patients after surgical resection improves over time, especially for patients with initial high-risk characteristics. Information derived from conditional survival analysis may provide individualized approaches to surveillance and treatment of spinal chondrosarcoma.

LEVEL OF EVIDENCE

4.

Survival and Prognosis of Chondrosarcoma Subtypes: SEER Database Analysis

Chondrosarcomas are rare tumors and, historically, investigation of these tumors has been limited to small series and single-institution studies. There have been no studies that evaluated the identification or comparison of differences in prognostic factors between the five known non-conventional chondrosarcoma subtypes (myxoid, juxtacortical, clear-cell, mesenchymal, and dedifferentiated). The purpose of this paper was to determine the demographic, clinical, incidence, and tumor characteristics of all five known non-conventional chondrosarcoma subtypes, determine the 1-, 5-year, and median survival differences between these subtypes, and to determine the demographic and clinical variables that are significant prognostic indicators for each chondrosarcoma subtypes. We retrospectively reviewed the SEER database for all patients with non-conventional chondrosarcoma. χ² testing was used for correlations between clinical variables. Kaplan-Meier and Cox proportional hazard analysis were used to compare survival of the subtypes, and to assess the prognostic value of age group, race, sex, grade, anatomic location, and metastatic involvement. Several demographic characteristics including gender, race, age, and grade varied between chondrosarcoma subtypes. The tumor characteristics showed marked differences in presence of metastasis on presentation between the subtypes with increasing order of rate of metastasis with juxtacortical (2.1%), clear cell (5.7%), myxoid (7.6%), mesenchymal (10.6%), and the highest in dedifferentiated (19.8%). One-, 5-year, and median survival differed significantly between chondrosarcomas subtypes. The highest median survival was found in the juxtacortical subtype (97 months), followed by clear cell (79 months), myxoid (60 months), mesenchymal (33.5 months), and lowest in dedifferentiated (11 months). The only prognostic variable that was shown to significantly impact the survival of each non-conventional chondrosarcoma subtype was a metastatic disease at diagnosis (p = 0.03 to p < 0.001). Subtyping classification of chondrosarcoma should be made whenever possible, given differences in survival and prognostic factors between chondrosarcoma subtypes. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:311-319, 2020.

Malignant fibrous neoplasms of long bones: analysis of the surveillance, epidemiology, and end results database from 1973 to 2015

BACKGROUND

Malignant fibrous neoplasms (MFN) of long bones are rare lesions. Moreover, the prognostic determinants of MFN of long bones have not been reported. This study aimed to present epidemiological data and analyse the prognostic factors for survival in patients with MFN.

MATERIALS AND METHODS

The Surveillance, Epidemiology, and End Results (SEER) programme database was used to screen patients with malignant fibrous neoplasms (MFN) of long bones from 1973 to 2015, with attention to fibrosarcoma, fibromyxosarcoma, periosteal fibrosarcoma and malignant fibrous histiocytoma. The prognostic values of overall survival (OS) and cancer-specific survival (CSS) were assessed using the Cox proportional hazards regression model with univariate and multivariate analyses. The Kaplan-Meier method was used to obtain OS and CSS curves.

RESULTS

A total of 237 cases were selected from the SEER database. Malignant fibrous histiocytoma was the most common form of lesion in long bones. Multivariate analysis revealed that independent predictors of OS included age, stage, tumour size and surgery. Age, stage, tumour size and surgery were also independent predictors of CSS. Additionally, the most significant prognostic factor was whether metastasis had occurred at the time of initial diagnosis.

CONCLUSION

Among patients with MFN of long bones, age (> 60 years), tumour size (> 10 cm), distant stage, and non-surgical treatment are factors for poor survival.

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.

Surgical treatment of metastatic mesenchymal chondrosarcoma to the spine: A case report

INTRODUCTION

Metastatic mesenchymal chondrosarcoma of the spine is a highly unusual disease without standard curative managements yet. The objective of this case report is to present a very rare case of metastatic chondrosarcoma to the spine successfully operated by surgical treatment. The management of these unique cases has yet to be well-documented.

PATIENT CONCERNS

A 34-year-old woman presented with a 4-month history of continuous and progressive back pain and a 1-month history of radiating pain of bilateral lower extremities. The patient, who had been diagnosed of mesenchymal chondrosarcoma of maxillary sinus for 3 years, received surgical treatment of palliative endoscopic-assisted total left maxillary resection via mini Caldwell-Luc approach, and palliative enlarged resection due to the progress of residual lesions, followed by no adjuvant therapy. Multiple lytic, expanding lesions of the spine and paraspinal region with severe epidural spinal cord compression was identified.

DIAGNOSIS

CT, MRI and bone scan of spine showed spinal cord compression secondary to the epidural component of the metastatic lesions. Post-operative pathology confirmed the diagnosis of metastatic spinal mesenchymal chondrosarcomas.

INTERVENTIONS

The patient underwent posterior spinal canal decompression, resection of T12 and L3 lesions, internal fixation of T11-L5 pedicles, and cement augmentation of T12 and L3.

OUTCOMES

The patient's neurological deficits improved significantly after the surgery, and the postoperative period was uneventful at the 1-year follow-up visit. There were no complications associated with the spinal surgery during the follow-up period.

CONCLUSION

Metastatic spinal mesenchymal chondrosarcoma, although rare, should be part of the differential diagnosis when the patient presents with back pain and radiculopathy. We recommend the posterior approach for spinal decompression and total resection of the metastatic chondrosarcoma when the tumor has caused neurological deficits or other severe symptoms. Osteoplasty by cement augmentation is also a good choice for surgical treatment in some patients.

Risk Factors for Incidence and Prognosis in Chondrosarcoma Patients with Pulmonary Metastasis at Initial Diagnosis

Background

The incidence and prognostic factors of chondrosarcoma patients have been reported in early studies. However, the association between risk factors and the incidence or prognosis of chondrosarcoma patients with pulmonary metastasis remains unclear. Therefore, we assessed these risk factors among chondrosarcoma patients with pulmonary metastasis.

Material/Methods

From 1365 chondrosarcoma patients in the Surveillance, Epidemiology, and End Results (SEER) database, we collected the information of 69 patients with pulmonary metastasis at the initial diagnosis of chondrosarcoma from 2010 to 2016. We investigated the incidence, risk factors, and prognostic factors for pulmonary metastasis patients by using multivariate logistic regression and multivariate Cox regression analyses.

Results

Data from a total of 69 (6.8%) chondrosarcoma patients with pulmonary metastasis at initial diagnosis were extracted. Patients with the following characteristics were positively associated with higher risk of pulmonary metastasis: dedifferentiated subtype, high grade of malignancy, extracompartmental tumor (Enneking B), presence of regional lymph nodes, local recurrence, large tumor size (larger than 15 cm), and being married. Older patients (older than 67 years), and patients with clear cell chondrosarcoma or large tumor size (larger than 15 cm) exhibited the worse prognosis and survival (overall and cancer-specific). Resection of the primary tumor tended to be correlated with a better prognosis.

Conclusions

The incidence of pulmonary metastasis in chondrosarcoma was approximately 6.8%, with poor prognosis. Identifying risk factors and their associations with the incidence and prognosis in chondrosarcoma patients with pulmonary metastasis could provide a reference for clinical surveillance and guide the design of personalized treatment plans.

Epidemiologic and survival trends in adult primary bone tumors of the spine

BACKGROUND CONTEXT

Malignant primary spinal tumors are rare making it difficult to perform large studies comparing epidemiologic, survival, and treatment trends. We investigated the largest registry of primary bone tumors, the National Cancer Database (NCDB), to compare epidemiologic and survival trends among these tumors.

PURPOSE

To use the NCDB to describe current epidemiologic trends, treatment modalities, and overall survival rates in patients with chordomas, osteosarcomas, chondrosarcomas, and Ewing sarcomas of the mobile spine. The secondary objective was to determine prognostic factors that impact overall survival rates.

STUDY DESIGN

Retrospective study.

PATIENT SAMPLE

A total of 1,011 patients with primary bone tumors of the spine (377 chordomas, 223 chondrosarcomas, 278 Ewing sarcomas, and 133 osteosarcomas).

OUTCOME MEASURES

Five-year survival.

METHODS

We reviewed the records of 1,011 patients in the NCDB from 2004 through 2015 with histologically confirmed primary osteosarcoma, chondrosarcoma, Ewing sarcoma, or chordoma of the spine. Demographic, clinical, and outcomes data were compiled and compared using chi-squared tests and ANOVA. Long-term survival was compared using the Kaplan-Meier method with statistical comparisons based on the log-rank test. Multivariate analysis was performed to determine survival determinants.

RESULTS

Surgical resection was the primary mode of treatment for chondrosarcoma (90%), chordoma (84%), and osteosarcoma (80%). The treatment for Ewing sarcoma was multimodal involving chemotherapy, radiation therapy, and surgical resection. Five-year survival rates varied significantly with chordomas and chondrosarcomas having the greatest survival (70% and 69%), osteosarcomas having the worse survival (38%), and Ewing having intermediate 5-year survival at 62% (overall log-rank p<.0001). Multivariate analysis demonstrated significantly improved 5-year survival rates with younger age at diagnosis, private insurance status, lower comorbidity score, lower tumor grade, smaller tumor size, surgical resection, and negative surgical margin. Radiation therapy only improved survival for Ewing sarcoma.

CONCLUSIONS

This study provides the most comprehensive description of the epidemiologic, treatment, and survival trends of primary bone tumors of the mobile spine. Second, patient and tumor characteristics associated with improved 5-year survival were identified using a multivariate model.

Surgical treatment of chondrosarcoma of the sacrum with cement augmentation: A case report

RATIONALE

Chondrosarcoma of the sacrum is a highly unusual disease without standard curative managements yet. The objective of this study is to report a very rare case of chondrosarcoma of the sacrum successfully operated by percutaneous vertebroplasty. The management of these unique cases has yet to be well-documented.

PATIENT CONCERNS

A 45-year-old woman presented with a five-month history of continuous and progressive pain and numbness of left extremity. A lytic, expanding lesion of the sacrum and paraspinal region with severe epidural spinal cord compression was identified.

DIAGNOSIS

MRI of spine showed spinal cord compression secondary to the epidural componant of the giant mass, with increased marrow infiltration of the left S2 vertebral and paravertebral region, which presented as a solid tumor. Post-operative pathology confirmed the diagnosis of sacral well-differentiated chondrosarcoma (stage I B).

INTERVENTIONS

The patient underwent percutaneous vertebroplasty and cement augmentation of sacrum via a posterior approach.

OUTCOMES

The patient's neurological deficits improved significantly after the surgery, but the patient died of multiple systemic metastases at the 2-year follow-up visit. There were no complications associated with the operation during the follow-up period.

LESSONS

Taken together, the lesion's clinical features, imaging results, and pathological characteristics are unique. Combined efforts of specialists from orthopedics, radiology, neurosurgery, pathology, and medical oncology led to the successful diagnosis and management of this patient. Giant sacral chondrosarcoma, although rare, should be part of the differential diagnosis when the patient presents with back pain and radiculopathy. We recommend the posterior approach for spinal decompression of the sacral chondrosarcoma when the tumor has caused neurological deficits or other severe symptoms. Osteoplasty by cement augmentation is also a good choice for surgical treatment.

Prognostic Factors and Treatment Options for Patients with High-Grade Chondrosarcoma

Background

The goal of this study was to determine the prognostic factors exclusive for high-grade chondrosarcoma and whether adjuvant radiotherapy could achieve better overall survival (OS) or cancer-specific survival (CSS) for patients with high-grade chondrosarcoma.

Material/Methods

Surveillance, Epidemiology, and End Results (SEER) cancer registry database was utilized to extract the chondrosarcoma cases diagnosed between 1973 and 2014. Among these cases, the histological grades of poorly differentiated (grade 3) and undifferentiated (grade 4) were categorized as high-grade and included in this study. Chondrosarcoma OS and CSS were the primary outcomes in the present study. The log-rank test was performed for univariate analysis, and the Cox regression model was conducted for multivariate analysis.

Results

A total of 743 patients with high-grade chondrosarcoma were identified in this study (430 cases were poorly differentiated tumors, and 313 cases were undifferentiated tumors). Age at diagnosis, pathological grade, histo-type, SEER stage, tumor size and surgical resection were identified as independent predictors in both OS and CSS analysis of high-grade chondrosarcoma. When stratified by histological grade, surgical resection remained the effective treatment. Strikingly, radiotherapy was determined as an independent protective factor in both OS and CSS analysis of undifferentiated (grade 4) dedifferentiated chondrosarcoma, and adjuvant radiotherapy combined surgical resection could improve both the OS and CSS of patients with undifferentiated myxoid and dedifferentiated chondrosarcoma compared with other treatment regimens.

Conclusions

Our study first demonstrated that adjuvant radiotherapy combined surgery could improve the survival of patients with undifferentiated myxoid and dedifferentiated chondrosarcoma. These results encourage the application of adjuvant radiotherapy for patients with high-grade chondrosarcoma and maximize the patients’ outcome.

Epithelioid Hemangioma of the Thoracic Spine: A Case Report and Review of the Literature

Context: Osseous epithelioid hemangioma is uncommon, and reports of epithelioid hemangiomas of the spine are especially rare.Study Design: Case report.Findings: A 43-year-old male was referred to our department with progressive gait disturbance. CT scans showed a lucent mass in the vertebral body at the T3 level. MRI of the thoracic spine showed a strongly enhanced mass compressing the spinal cord. The patient underwent laminectomy from T2 to T4, debulking of the tumor, and posterior fusion from T1 to T5. After the operation, the patient's neurological status improved significantly, and he was able walk without assistance. Histological examination determined that the tumor was an epithelioid hemangioma. The patient was treated with 40 Gy radiation for local control of the tumor. The patient could walk without difficulty 12 months after the surgery.Conclusion: This is a rare example of an epithelioid hemangioma that developed in the thoracic spine and compressed the spinal cord, and was treated successfully.

Revisiting the Role of Radiation Therapy in Chondrosarcoma: A National Cancer Database Study

Background

Although chondrosarcomas (CS) are mostly considered radioresistant, advancements in radiotherapy have brought attention to its use in these patients. Using the largest registry of primary bone tumors, the National Cancer Database (NCDB), we sought to better characterize the current use of radiotherapy in CS patients and identify any potential survival benefit with higher radiation doses and advanced radiation therapies.

Methods

We retrospectively analyzed CS patients in the NCDB from 2004 to 2015 who underwent radiotherapy. The Kaplan–Meier method with statistical comparisons was used to identify which individual variables related to dosage and delivery modality were associated with improved 5-year survival rates. Multivariate proportional hazards analyses were performed to determine independent predictors of survival.

Results

Of 5,427 patients with a histologic diagnosis of chondrosarcoma, 680 received a form of radiation therapy (13%). The multivariate proportional hazards analysis controlling for various patient, tumor, and treatment variables, including RT dose and modality, demonstrated that while overall radiation therapy (RT) was not associated with improved survival (HR 0.96, 95% CI 0.76–1.20), when examining just the patient cohort with positive surgical margins, RT trended towards improved survival (HR 0.81, 95% CI 0.58–1.13). When comparing advanced and conventional RT modalities, advanced RT was associated with significantly decreased mortality (HR 0.55, 95% CI 0.38–0.80). However, advanced modality and high-dose RT both trended only toward improved survival compared to patients who did not receive any RT (HR 0.74, 95% CI 0.52–1.06 and HR 0.93, 95% CI 0.71–1.21, respectively).

Conclusions

Despite the suggested radioresistance of CS, modern radiotherapies may present a treatment option for certain patients. Our results support a role for high-dose, advanced radiation therapies in selected high-risk CS patients with tumors in surgically challenging locations or unplanned positive margins. While there is an associated survival rate benefit, further, prospective studies are needed for validation.

Overexpression of ClC-3 Chloride Channel in Chondrosarcoma: An In Vivo Immunohistochemical Study with Tissue Microarray

Background

Recently, ClC-3 chloride channel expression has been noted to be high in some tumors. In chondrosarcoma, which is a malignant tumor with a high incidence in the bone, there has been no previous literature regarding ClC-3 chloride channel expression. Here we evaluated the expression of ClC-3 chloride channel in chondrosarcoma and explored its clinical significance.

Material/Methods

In this study, 75 chondrosarcoma and 5 normal cartilage tissues were collected. Thereafter, tissue microarray was performed. Immunohistochemistry was also used to observe the level of ClC-3 chloride channel expression between normal and chondrosarcoma tissues.

Results

Results showed that the expression of ClC-3 chloride channel in the normal chondrocyte was thinner, since it showed distinct differentiation among chondrosarcoma specimens. Interestingly, we noticed that the moderately-differentiated chondrosarcoma (MDC) and the poorly-differentiated chondrosarcoma (PDC) exhibited 94.44% of ClC-3 chloride channel. Besides, the subcellular localization of ClC-3 chloride channel was changed in association with malignant degree changes. The subcellular localization of ClC-3 chloride channel in the MDC and PDC tissue was localized in the cytoplasm and both nucleus and cytoplasm: 83.33% (5 out of 6 cases) and 91.66% (11 out of 12 cases) respectively. On the other hand, we noticed that patient age and gender could have a relation with ClC-3 chloride channel expression; 30- to 60-year-old males showed more expression.

Conclusions

These results demonstrated a high frequency of ClC-3 chloride channel overexpression and subcellular localization differences in MDC and PDC tissue, suggesting a specific role of ClC-3 chloride channel in the pathogenesis of chondrosarcoma.

Spinal sarcomas and immunity: An undervalued relationship

Sarcomas, especially spine sarcomas, are rare yet debilitating and are underestimated types of cancer. Treatment options for spine sarcomas are limited to chemotherapy, radiotherapy and surgical intervention. Accumulating evidence suggests a complex course associated with the treatment of spine sarcomas as compared to other soft tissue sarcomas in the extremities since adjuvant therapy adds limited success to the oncological outcome. Likewise, the limitations of surgical interventions imposed by the proximity and high sensitivity of the spinal cord, leads to an increased recurrence and mortality rates associated with spine sarcomas. Finding novel treatment options to spine sarcomas as such is inevitable, necessitating a more thorough understanding of the different mechanisms of the underlying etiologies of these tumors. In this review, we discuss the most recent studies tackling the involvement of the immune system; a key player in the emergence of the different types of spine sarcomas and the promising immune-mediated targeted therapy that can be applied in these kind of rare cancers.

Development and validation of a nomogram containing the prognostic determinants of chondrosarcoma based on the Surveillance, Epidemiology, and End Results database

BACKGROUND

We aimed to develop and validate a reliable nomogram for predicting the disease-specific survival (DSS) of chondrosarcoma patients.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was queried from 2004 to 2015 to identify cases of histologically confirmed chondrosarcoma. Multivariate Cox regression analysis was performed to identify independent prognostic factors and construct a nomogram for predicting the 3- and 5-year DSS rates. Predictive values were compared between the new model and the American Joint Committee on Cancer (AJCC) staging system using concordance indexes (C-indexes), calibration plots, integrated discrimination improvement (IDI), net reclassification improvement (NRI), and decision curve analysis (DCA).

RESULTS

Multivariate Cox regression identified 1180 patients, who were used to establish a nomogram based on a new model containing the predictive variables of age, socioeconomic status, tumor size, surgery status, chemotherapy status, and AJCC staging. In the nomogram, age at diagnosis is the factor with the highest risk, followed by AJCC stage IV and tumor size > 100 mm. Both the C-index and the calibration plots demonstrated the good performance of the nomogram. Moreover, both NRI and IDI were improved compared to the AJCC staging system, and also DCA demonstrated that the nomogram is clinically useful.

CONCLUSION

We have developed a reliable nomogram for determining the prognosis and treatment outcomes of chondrosarcoma patients that is superior to the traditional AJCC staging system.

Predictors of the survival of patients with chondrosarcoma of bone and metastatic disease at diagnosis

Purpose: Chondrosarcoma with metastatic disease has a very poor prognosis. However, the prognosis and potential prognostic factors of patients with primary chondrosarcoma of bone and metastasis at presentation have not been documented because of its rarity. Therefore, we examined the prognosis of this special cohort and identify possible prognostic factors.

Methods: The Surveillance, Epidemiology, and End Results (SEER) program database was used to identify patients with primary chondrosarcoma of bone and metastatic disease at diagnosis from 2000 to 2013. The prognostic analysis was performed using the Kaplan-Meier method and a Cox proportional hazards regression model.

Results: The SEER database contained 264 cases. The overall survival (OS) and cancer-survival specific (CSS) rates of the entire group at 5 years were 28.4% and 31.2%, respectively. The median OS and CSS were 14.0 ± 2.5 and 17.0 ± 2.6 months, respectively. Multivariate analysis revealed that low tumor grade, surgical treatment, tumor size < 10 cm, and first primary tumor were associated with improved OS. Tumor grade, tumor size, and surgery were independent predictors of CSS. Radiation therapy had no effect on either OS or CSS.

Conclusion: Among patients with primary chondrosarcoma of bone and metastasis at presentation, low tumor grade, surgical treatment, tumor size < 10 cm, and first primary tumor predict prolonged survival.

Vertebral body chondrosarcoma with metastasis to the scalp

We present a case of a 30-year-old man who had a 3-year history of low back pain. MRI demonstrated an infiltrative mass, affecting the vertebral body and pedicles of L4, with some extension to the vertebral canal. There was also tumor invasion in the inferior vena cava and in the left iliopsoas muscle. The anatomopathological examination of the resected L4 vertebral body was of a malignant neoplasia compatible with mesenchymal chondrosarcoma (high histological grade). About 2 months after surgery, he developed a progressive bladder incontinence, bilateral leg weakness and severe back pain. A new MRI was obtained, confirming progression of the disease. An occipital scalp lesion was detected and biopsy confirmed cutaneous metastasis. Primary malignant bone tumors are rare but should be ruled out in young patients with persistent low back pain. We present a case of a confirmed mesenchymal chondrosarcoma affecting lumbar spine, with MRI and pathological illustrations. Early diagnosis may improve the chances of local disease control and even cure.

Clinical significance of traditional clinical parameters and inflammatory biomarkers for the prognosis of patients with spinal chondrosarcoma: a retrospective study of 150 patients in a single center

BACKGROUND

To investigate the clinical significance of five inflammatory biomarkers and conventional clinical parameters in prognostic prediction of spinal chondrosarcoma.

METHODS

Univariate and multivariate analyses were performed to investigate independent prognostic factors for recurrence and death of patients with spinal chondrosarcoma. Disease-free survival (DFS) and overall survival (OS) were estimated by Kaplan-Meier curve, and differences were analyzed by log-rank test. The optimal cutoff values for NLR, PLR, LMR, and CAR were determined by X-tile program.

RESULTS

The optimal cutoff value for NLR, PLR, LMR, AGR, and CAR was 2.7, 200, 3.0, 1.5, and 0.2, respectively. Of the 150 patients included, recurrence was detected in 105 patients, and death occurred in 78 patients. Multivariate analysis indicated that Tomita I-III, total resection, and CAR < 0.2 were significantly associated with longer DFS. Meanwhile, preoperative Frankel score D-E, total resection, and CAR < 0.2 were favorable prognostic factors for OS. Subtype analysis showed that only total resection was an independent prognostic factor for DFS of recurrent spinal chondrosarcoma.

CONCLUSION

Total resection could significantly reduce the recurrence rate of spinal chondrosarcoma and improve OS of chondrosarcoma patients. Tomita classification I-III was a favorable factor for DFS, and preoperative Frankel score A-C was an adverse prognostic factor for OS. CAR was the most robust prognostic indicator with a discriminatory ability as compared with other inflammatory indicators. These slides can be retrieved under Electronic Supplementary Material.

Total en bloc resection of primary and metastatic spine tumors

Primary and metastatic tumors of the spine represent a significant cause of patient morbidity, and present a management challenge to treating providers. From a neurosurgical standpoint, resection surgery may be warranted in cases of spinal instability, progressive disease, neurological compromise, or intractable symptoms. Removal of a tumor "en bloc" offers a more aggressive modality over more conservative resection techniques. En bloc resection entails the removal of the entirety of a tumor without violation of its capsule, and may offer improved rates of local control and overall survival in appropriately selected patients. Conversely, this technique carries a higher complication rate, and requires a unique set of technical skills as compared to more traditional resection. Here, we describe the technical aspects of en bloc resection, as well as specific indications and considerations when employing this operative technique.

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.

Chondrosarcoma in a paediatric population: a study of 247 cases

PURPOSE

The aims of present study are to clarify the follow questions: 1) what constitutes paediatric chondrosarcoma?; 2) what are the effects of the demographic and tumour characteristics on survival in patients with paediatric chondrosarcoma?; 3) which prognostic factors of paediatric chondrosarcoma differ from those of the adult population, which have been reported previously?

METHODS

Paediatric patients who were diagnosed with chondrosarcoma were searched for using the case listing session protocol of the National Cancer Institute's Surveillance, Epidemiology, and End Results 18 databases (1973 to 2014). The extracted demographic information includes: age, race, gender, year of diagnosis, tumour sites, tumour histological subtype, grade, stage and treatment.

RESULTS

A total of 247 paediatric chondrosarcoma patients were extracted and included in our present study. We find that the paediatric patients have significantly better survival rates than the adult patients. The year of diagnosis, tumour sites, tumour histological subtype, grade, stage and surgery received are independent prognostic factors for the survival rate of paediatric chondrosarcoma patients, but race, gender and age are not.

CONCLUSION

The paediatric chondrosarcoma patients have better survival rates than the adults. Paediatric patients with a diagnosis at an early age, tumour site at the vertebral column and pelvis/sacrococcyx, myxoid variants, high grade, distant stage and who did not have surgery have a poorer prognosis than patients with a diagnosis at a later age, tumour site at limbs, head and base, chondrosarcoma not otherwise specified, lower grade, localized stage and who received surgery.

LEVEL OF EVIDENCE

II -Prognostic Study.

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.