Evidence-based Tumor Staging of Skeletal Chondrosarcoma

Prognostic Factors and Surgical Impact of Non-metastatic Conventional Chondrosarcoma of the Extremities

OBJECTIVE

Chondrosarcoma is a common bone malignancy, and the main treatment method is surgery. Different surgeries lead to different survival outcomes. The aim of this study was to construct a new clinical predictive tool to accurately predict the overall survival (OS) and cause specific survival (CSS) of patients with chondrosarcoma receiving different treatments.

METHODS

A total of 620 patients with chondrosarcoma registered between January 1, 2000 and December 31, 2016 were recruited as study targets. The missing values are filled by multiple imputation. Two continuous variables, age and tumor size, were divided into binary variables based on Kaplan-Meier curve. Univariate and multivariate analyses were used to explore predictors and establish nomograms. Propensity score matching (PSM) analysis was used to reduce the impact of potential confounders to determine whether different surgical modalities had any survival benefits in subgroups.

RESULTS

In a multivariate cox regression, age, grade, tumor size, radiotherapy, chemotherapy, and surgical methods were identified as independent prognostic factors for chondrosarcoma. To construct 1-, 3-, and 5-year nomogram maps of OS and CSS with prognostic factors and verify the c index internally (OS, 0.807; CSS, 0.847) above American Joint Committee on Cancer (AJCC) (OS, 0.685; CSS, 0.732).

CONCLUSION

This study found that the 5 year overall survival rate of patients with non-metastatic chondrosarcoma of the extremities was about 80%. Age, high malignancy, large tumor, prior chemoradiotherapy, and poor surgical selection were independent risk factors. Therefore, the nomogram established in this study will help to optimize clinicians' personalized decision making for patients.

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.

Tumor necrosis is an underappreciated histopathologic factor in the grading of chondrosarcoma

BACKGROUND

Cartilaginous neoplasms can be challenging to grade; there is a need to create an evidence-based rubric for grading. The goal of this study was to identify histopathologic features of chondrosarcoma that were associated with 5-year survival and to compare these to traditional patient, tumor and treatment variables.

METHODS

This was a retrospective review of all patients undergoing surgical resection of a primary chondrosarcoma with at least 2 years of follow up. All specimens were independently reviewed by two pathologists and histopathologic features scored. Univariate and multivariate analyses were performed utilizing Kaplan Meier and proportional hazards methods to identify variables associated with 5-year disease specific survival (DSS) and disease free survival (DFS).

RESULTS

We identified 51 patients with an average follow up of 49 months eligible for inclusion. 30% of tumors were low grade, 45% were intermediate grade, and 25% were high grade. In a univariate analysis considering histopathologic factors, higher tumor mitotic rate (HR 8.9, p < 0.001), tumor dedifferentiation (HR 7.3, p < 0.001), increased tumor cellularity (HR 5.8, p = 0.001), increased tumor atypia (HR 5.8, p = 0.001), LVI (HR 4.7, p = 0.04) and higher tumor necrosis (HR 3.7, p = 0.02) were all associated with worse 5-year DSS. In a multivariate analysis controlling for potentially confounding variables, higher tumor necrosis was significantly associated with disease specific survival survival (HR 3.58, p = 0.035); none of the factors were associated with DFS.

CONCLUSIONS

This study provides an evidence-based means for considering histopathologic markers and their association with prognosis in chondrosarcoma. Our findings suggest that necrosis and LVI warrant further study.

The national incidence of chondrosarcoma of bone; a review

BACKGROUND

Chondrosarcoma (CS) epidemiology has been studied by a number of authors using national cancer registry cohorts. Many reports share the common findings of a slight increase in incidence, but not all. The patterns and causes for these changes are divergent while reflection concerning methodological challenges are often missing.

METHOD

We have performed a structured literature review to find national analyses of CS incidence published from 2010 to 2020. We included eight studies of national incidence of CS, summarise their findings and patterns of change. We further discuss explanations given for these changes to better understand the real patterns and raise awareness in their interpretation.

RESULTS

Reported crude incidence ranges from 0.27 per million per year overall in Saudi Arabia to 5.4 in the Netherlands. Four studies from the USA, England, Switzerland and France report age standardised rates of 2.0-4.1 per million per year overall. While some countries report stable patterns, most report a slight increase. The Netherlands is the only country reporting a large increase, driven by a 10-fold increase in the incidence of ACT/grade 1 CS during the study period. We challenge the explanations given for this and suggest that this most likely is a result of variable interpretation and definition of CS at the lower levels of disease aggressiveness. This should raise awareness to possible over-treatment of CS in the Netherlands.

CONCLUSION

The most likely national incidence of CS of bone is between 2-4 per million per year. Three modern reports present an incidence of 3.4-4.1 per million per year.

A proposed risk assessment score for gastrointestinal stromal tumors based on evaluation of 19,030 cases from the National Cancer Database

BACKGROUND

Standard risk assessment algorithms for gastrointestinal stromal tumor (GIST) are based on anatomic and histopathological variables with arbitrarily defined subcategories. Our goal was to improve risk assessment for GIST through retrospective analysis of patient data.

METHODS

The National Cancer Database (NCDB) was queried for patients with GIST; the final cohort consisted of 19,030 cases. Main outcomes were metastasis at presentation and overall survival. A test dataset was used to reevaluate risk stratification parameters in multivariate regression models. A novel risk assessment system was applied to the validation dataset and compared to other currently used risk assessment schemes.

RESULTS

Analysis of observed prevalence of metastases at presentation suggested 7 cm and mitotic rates > 10 per 5 mm² as optimal threshold values. A proposed risk stratification score showed statistical superiority compared to the National Comprehensive Cancer Network, American Joint Committee on Cancer, and modified National Institute of Health classifications in predicting probability of presentation with metastasis at diagnosis and 4-year overall survival after accounting for important covariables including patient age and comorbidities, year of diagnosis, and surgical/systemic therapeutic regimen.

CONCLUSIONS

Reexamination of prognostic factors for GIST demonstrated that current threshold values for tumor size and mitotic rate are suboptimal. A risk stratification score based on revised categorization of these factors outperformed currently used risk assessment algorithms.

Safety Analysis of Apatinib Combined with Chemotherapy in the Treatment of Advanced Gastric Carcinoma: A Randomised Controlled Trial

Objective

To study the safety of apatinib combined with chemotherapy in the treatment of advanced gastric carcinoma (GCA).

Methods

74 patients with advanced GCA treated in the oncology department of Weifang People's Hospital (January 2019–January 2020) were enrolled in this study and equally split into study group (SG) and reference group (RG) according to the odd and even admission numbers. RG underwent chemotherapy alone, while SG received apatinib combined with chemotherapy. The clinical indicators of serum matrix metalloproteinase 9 (MMP-9), serum interleukin-2 receptor (SIL-2R), and immune cell level were detected in the two groups before and after treatment to analyze the therapeutic effect of different treatment methods on patients with advanced gastric carcinoma.

Results

No obvious differences in gender ratio, average age, average BMI, pathological staging, pathological types, organ metastasis types, and residence were observed between the two groups (P > 0.05). The short-term follow-up results showed that the disease control rate (DCR) in SG was markedly higher compared with RG (P < 0.05). The MMP-9 and SIL-2R levels in both groups after treatment decreased (P < 0.05), and the levels in SG after treatment were notably lower compared with RG (P < 0.001). Compared with RG, CD3⁺, CD4⁺, and CD4⁺/CD8⁺ levels in SG after treatment were notably higher (P < 0.001), while the CD8⁺ level was notably lower (P < 0.001). The median progression-free survival (MPFS) and overall survival (OS) in SG were markedly higher compared with RG (P < 0.001). The GQOLI-74 scores in both groups after treatment increased (P < 0.001), and the GQOLI-74 score in SG after treatment was markedly higher compared with RG (P < 0.001). The total incidence of adverse reactions was lower in SG than in RG (P < 0.05).

Conclusion

Apatinib combined with chemotherapy is superior to chemotherapy alone in effectively improving treatment outcomes in patients with advanced GCA.

Risk Assessment of Visceral Sarcomas: A Comparative Study of 2698 Cases from the SEER Database

Soft tissue sarcomas arising in visceral organs are rare and lack validated tumor-staging protocols. Clinicopathologic features and clinical outcomes of 2698 visceral sarcomas identified in the Surveillance, Epidemiology, and End Results Program (SEER) database were compared with sarcomas arising in the extremities/trunk (n = 10,237) or retroperitoneum (n = 1067) using standard statistical techniques. Important prognostic criteria for visceral sarcomas, as in other anatomic sites, included tumor size, histologic grade, and presence of metastatic disease. After adjustment for pertinent confounding factors, visceral sarcomas showed cancer-specific survival rates similar to those arising in the retroperitoneum but had worse outcomes than sarcomas in the extremities/trunk. Therefore, the prognostic performance of two different staging algorithms for retroperitoneal sarcomas was evaluated for their use in staging sarcomas of visceral organs. The current AJCC 8th edition and the recently derived Vanderbilt system for staging retroperitoneal sarcoma both showed adequate discrimination, as assessed by multiple clinical concordance indices, and no evidence of miscalibration. Therefore, the authors concluded that previously validated staging systems for retroperitoneal sarcomas based on conventional prognostic factors (histologic grade, tumor size, and presence of metastatic disease) are applicable to visceral sarcomas and should be incorporated into the next edition of the AJCC Cancer Staging Manual.

A Proposed Staging System for Improved Prognostication of MDM2-amplified Liposarcoma

Despite the release of anatomic site-specific staging systems for soft tissue sarcomas in the eighth edition of the American Joint Committee on Cancer (AJCC) Cancer Staging Manual, the algorithms for sarcomas arising in the extremities/trunk and retroperitoneum differ only in the staging of lymph node metastasis. The retroperitoneum not only provides a larger potential space for tumor growth before the clinical presentation, but its anatomic complexities complicate surgical resection and adversely affect disease-free survival. Here, we propose a new staging system for MDM2-amplified liposarcomas (well-differentiated and dedifferentiated subtypes) that properly emphasizes retroperitoneal localization, degree of differentiation (histologic subtype), and presence of distant metastasis. A retrospective cohort of 4146 adult patients with surgically resected liposarcoma was extracted from the SEER database to compare the natural history of MDM2-amplified liposarcomas arising in the extremities/trunk or retroperitoneum. Separate training and validation datasets were created, and Cox proportional hazard regression, multivariable nonlinear regression, and nomographic analyses determined the most significant parameters in predicting sarcoma-specific death. A new staging system was derived and its predictive accuracy was compared with the AJCC, eighth edition system using areas under receiver operating characteristic curves and multiple concordance indices. Multivariable analysis showed that dedifferentiation (hazard ratio [HR]=3.7±0.5; P<0.0005), retroperitoneal location (HR=3.2±0.5; P<0.0005), and distant metastasis (HR=2.4±0.6; P=0.002), but not categorized tumor size (pT category), had the largest effects on sarcoma-specific survival. A new staging system based on these predictive factors demonstrated better discrimination between tumor stages, higher concordance with clinical outcomes, and greater predictive accuracy than the AJCC eighth edition staging system (86±1% vs. 83±2%; P=0.005). Statistical analysis of a large national cohort failed to confirm that categorized tumor size is a useful criterion by which to stage MDM2-amplified liposarcoma. A simplified staging system based on anatomic location and dedifferentiation outperforms the current AJCC staging system. Anatomic localization and histologic grade, and not tumor size, should be included in any future liposarcoma-specific staging system.

Chondrosarcoma local recurrence in the Cancer Registry of Norway cohort (1990-2013): Patterns and impact

BACKGROUND

There appears to be an association between local recurrence (LR) and risk of metastasis and death in central conventional chondrosarcoma (CCCS) of bone, but this has not been quantified in modern cohorts at a subtype level.

METHODS

We identified nonmetastatic cases of CCCS (N = 180) from the Cancer Registry of Norway. We present prognostic analysis of LR accounting for immortal time bias by descriptive statistics and multivariable Cox models.

RESULTS

Of 40 LR, one case demonstrated upgrading while two dedifferentiation. LR was associated with increased risk of metastasis (hazard ratio [HR] = 4.1 [confidence interval, 1.5-10.7]) and death (HR = 9.3 [5.0-17.5]) overall. LR was associated with significant increased risk of metastasis for those with a soft tissue component, axial location, malignancy grade 2, but not atypical cartilaginous tumor's, appropriately treated curettage patients, intramedullary tumors, grade 1 histology, extremity location or "Oslo low risk" group status. We found an increased risk of death for all groups except for those treated by appropriate curettage or belonging to the "Oslo low risk" group. About 50% of LR CCCS were asymptomatic and revealed by routine follow-up.

CONCLUSIONS

Upgrading of LR for CCCS was a seldom event. LR was associated with significant increased risk of metastasis and death overall, but not for appropriately treated curettage patients or "Oslo low risk" status.