Pathological fracture does not affect prognosis in dedifferentiated chondrosarcoma of the limbs

Predicting survival outcomes in dedifferentiated chondrosarcoma: a prognostic factor analysis from a National Registry

INTRODUCTION

Dedifferentiated chondrosarcoma (DDCS) is a high-grade subtype of chondrosarcoma with a poor prognosis. Treatment for localized DDCS generally involves wide resection; the effectiveness of adjuvant radiotherapy and chemotherapy is questionable. This research was designed to find prognostic factors for DDCS and evaluate the impact of adjuvant therapies on localized cases.

METHODS

One hundred thirty-two patients with DDCS diagnosed by pathology in the period 2006 to 2022 were identified in the Japanese National Bone and Soft Tissue Tumor Registry database and were retrospectively analyzed.

RESULTS

Patients with distant metastases at diagnosis (n = 34) had significantly poorer survival than those without metastases (n = 98), with a 5-year disease-specific survival (DSS) of 9.7% vs. 37.1% (P < 0.0001). For patients without distant metastasis at diagnosis, uni- and multivariate analysis showed that R1 or R2 surgical margin was an independent risk factor linked with unfavorable local recurrence (hazard ratio [HR] 3.39 [95% CI: 1.35-8.52]; P = 0.010). Adjuvant radiotherapy was not associated with local recurrence (HR 2.41 [95% CI: 0.87-6.64]; P = 0.090). Larger size (HR 1.13 [95% CI: 1.06-1.19]; P < 0.001) and no surgery (HR 3.87 [95% CI: 1.61-9.28]; P = 0.002) were independent risk factors for unfavorable DSS. Previous surgery (HR 0.19 [95% CI: 0.04-0.84]; P = 0.028) and adjuvant chemotherapy (HR 0.36 [95% CI: 0.16-0.77]; P = 0.009) were independent risk factors for favorable DSS.

DISCUSSION

Survival may have been improved by chemotherapy, but the effect of adjuvant radiotherapy in controlling the local spread of the tumor appears to have been limited in DDCS cases that were localized.

UK guidelines for the management of bone sarcomas

This document is an update of the British Sarcoma Group guidelines (2016) and provides a reference standard for the clinical care of UK patients with primary malignant bone tumours (PMBT) and giant cell tumours (GCTB) of bone. The guidelines recommend treatments that are effective and should be available in the UK, and support decisions about management and service delivery. The document represents a consensus amongst British Sarcoma Group members in 2024. Key recommendations are that bone pain, or a palpable mass should always lead to further investigation and that patients with clinical or radiological findings suggestive of a primary bone tumour at any anatomic site should be referred to a specialist centre and managed by an accredited bone sarcoma multidisciplinary team. Treatment recommendations are provided for the major tumour types and for localised, metastatic and recurrent disease. Follow-up schedules are suggested.

The clinical outcomes and prognostic factors of dedifferentiated central chondrosarcoma in extremities

OBJECTIVE

This study was to analyze the clinical outcomes and prognostic factors of dedifferentiated central chondrosarcomas (DCCS) in extremities.

METHODS

A retrospective study was conducted on 49 patients (27 males, 22 females) who underwent surgical treatment between January 2001 and March 2023 in our institution. All patients were diagnosed with dedifferentiated central chondrosarcomas by needle biopsy or postoperative histopathological examination. The general characters, treatment and clinical outcomes were recorded in the follow-up and all surgical-related complications that occurred were recorded in this study. Overall, these data were used to analyse the prognostic factors of DCCS.

RESULTS

49 patients were included in this retrospective study and there were no patients lost in the follow-up period. The median diagnosis age of all patients was 57 years old (ranging from 17 to 87) and the median follow-up time was 34 months (range, 1-289). The average tumor size was 9.6 ± 2.4 cm (3.0-15.5). Median overall survival (OS) and progression-free survival (PFS) were 34 and 23 months, respectively. The 1-year, 2-year, 5-year, and 10-year OS were 87.8% (95% CI 77.6%-98.0%), 71.4% (35/49), 28.6% (14/49) and 18.4% (9/49). And the 1-year, 2-year, 5-year, and 10-year PFS were 75.5% (95% CI 63.6%-87.4%), 49.0% (35/49), 26.5% (14/49) and 16.3% (9/49). Multiple variate analyses indicated metastasis, pathological fracture, Enneking staging and surgical margin were independent prognostic factors in extremity dedifferentiated central chondrosarcomas.

CONCLUSIONS

Dedifferentiated central chondrosarcomas in extremities still had a grave prognosis. Metastasis, pathological fracture, Enneking staging, and surgical margin were independent risk factors for prognosis.

EVIDENCE LEVEL

IV Therapic.

A Systematic Review of Adjuvant Chemotherapy in Localized Dedifferentiated Chondrosarcoma

Dedifferentiated chondrosarcoma (DDCS) is a high-grade subtype of chondrosarcoma with the bimorphic histological appearance of a conventional chondrosarcoma component with abrupt transition to a high-grade, non-cartilaginous sarcoma. DDCS can be radiographically divided into central and peripheral types. Wide resection is currently the main therapeutic option for localized DDCS. Moreover, the effectiveness of adjuvant chemotherapy remains controversial. Therefore, we performed a systematic review of available evidence to evaluate the effect of adjuvant chemotherapy on localized DDCS. The purpose was to compare the 5-year survival rate among patients treated with surgery plus adjuvant chemotherapy or surgery alone for localized DDCS. The search was conducted in PubMed, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) databases. Of the 217 studies shortlisted, 11 retrospective non-randomized studies (comprising 556 patients with localized DDCS) were selected. The 5-year survival rates were similar between the two treatment groups (28.2% (51/181) vs. 24.0% (90/375), respectively). The overall pooled odds ratio was 1.25 (95% confidence interval: 0.80-1.94; p = 0.324), and heterogeneity I2 was 2%. However, when limited to peripheral DDCS, adjuvant chemotherapy was associated with prolonged survival (p = 0.03). Due to the paucity of included studies and the absence of prospective comparative studies, no conclusions can be drawn regarding the effectiveness or ineffectiveness of adjuvant chemotherapy for localized DDCS.

Dedifferentiated Chondrosarcoma from Molecular Pathology to Current Treatment and Clinical Trials

Dedifferentiated chondrosarcoma (DDCS) is a rare subtype of chondrosarcoma, a primary cartilaginous malignant neoplasm. It accounts for up to 1-2% of all chondrosarcomas and is generally associated with one of the poorest prognoses among all chondrosarcomas with the highest risk of metastasis. The 5-year survival rates range from 7% to 24%. DDCS may develop at any age, but the average presentation age is over 50. The most common locations are the femur, pelvis humerus, scapula, rib, and tibia. The standard treatment for localised disease is surgical resection. Most patients are diagnosed in unresectable and advanced stages, and chemotherapy for localised and metastatic dedifferentiated DDCS follows protocols used for osteosarcoma.

Comparative analysis of miRNA expression in dedifferentiated and well-differentiated components of dedifferentiated chondrosarcoma

Dedifferentiated chondrosarcoma (DDCS) is a rare malignant cartilage tumor arising out of a low-grade chondrosarcoma, whereby the well-differentiated and the dedifferentiated components coexist in the same localization. DDCS has a massively increased metastatic potential in comparison to low-grade chondrosarcoma. So far, the underlying mechanisms of DDCS development and the increased malignancy are widely unknown. Targeted DNA sequencing revealed no genetic differences between both tissue components. Besides genetic events, alterations in epigenetic control may play a role in DDCS development. In this preliminary study, we have analyzed the differential miRNA expression in paired samples of both components of four primary DDCS cases and a rare lung metastasis with both components using the nCounter MAX analysis system from NanoString technologies. We identified 21 upregulated and two downregulated miRNAs in the dedifferentiated components of the primary cases. Moreover, three miRNAs were also significantly deregulated in the dedifferentiated component of the lung metastasis, supporting their possible role in DDCS development. Additionally, validated targets of the 23 deregulated miRNAs are involved in signaling pathways, like PI3K/Akt, Wnt/β-catenin, and TGF-β, as well as in cellular processes, like cell cycle regulation, apoptosis, and dedifferentiation. Further investigations are necessary to confirm and understand the role of the identified miRNAs in DDCS development.

Dedifferentiated Chondrosarcoma: A Case Series and Review of the Literature

BACKGROUND

Dedifferentiated chondrosarcoma (DCS) is a rare and aggressive malignancy with a poor prognosis. The purpose of this investigation was to describe our treatment and outcomes of 16 DCS patients at our institution and provide a review of the current literature.

METHODS

This study was a retrospective review over a consecutive twenty-year period. Data including treatment details and outcomes were recorded.

RESULTS

A total of 16 cases from 2000 to 2018 were identified. The median age (IQR) was 62 years (52; 69) and the majority of DCS arose in the femur (50%, n=8) and pelvis (25%, n=4). Fourteen (88%) cases underwent limb salvage/wide margin resection (n=13) or intralesional surgery (n=1). For all DCS, the median survival (IQR) was 46 months (12; 140), with both a five and ten-year probability of 32.1% (95% CI, 7.3% to 57.0%). At study conclusion, 81.3% (n=13) were deceased and 18.7% (n=3) were alive.

CONCLUSIONS

Our findings confirm the poor prognosis of DCS patients, with a five-year estimate of 32%. Together with existing literature, our data might help enable future strategic recommendation of these patients.

Clinical features and treatment outcomes of dedifferentiated and grade 3 chondrosarcoma: A multi-institutional study

Chondrosarcoma is the second most common primary malignant bone tumor. In this multicenter study, we sought to evaluate the (i) disease-specific survival (DSS) and disease-free survival (DFS), and (ii) prognostic factors in patients with dedifferentiated chondrosarcoma (DDCS) and grade 3 chondrosarcoma (G3CS) in Japan. We retrospectively investigated the treatment outcomes and prognostic factors in 62 patients with DDCS and 19 patients with G3CS at 15 institutions participating in the Japanese Musculoskeletal Oncology Group. We also clarified significant clinico-pathological factors for oncological outcomes. In surgery for primary lesions aimed at cure, a histologically negative margin (R0) was obtained in 93% (14/15) of patients with G3CS and 100% (49/49) of patients with DDCS. The 5-year DSS was 18.5% in patients with DDCS and 41.7% in patients with G3CS (P = 0.13). Local control was obtained in 80% (12/15) and 79.6% (39/49) of patients with G3CS and DDCS in the primary lesion after surgery with a wide surgical margin, respectively. In multivariate analysis, stage and no treatment/palliative treatment for the primary lesion were independent prognostic factors for DSS of DDCS, age and no treatment/palliative treatment for DSS of G3CS. The 5-year DFS rate was 22.8% in 26 patients with DDCS who did not receive adjuvant chemotherapy, and 21.4% in 14 patients who received adjuvant chemotherapy. The prognosis of DDCS remains poor, although R0 resection was performed in most cases. Effective and/or intensive chemotherapeutic regimens or agents should be considered or developed for patients with high-grade chondrosarcoma, particularly for those with DDCS.

Periostin is a novel histological biomarker for the diagnosis of chondroid tumor

Background

The chondroid tumor is generally classified into three types, enchondroma, low-grade chondrosarcoma, and high-grade chondrosarcoma. A histological evaluation of a biopsy sample is the best predictor of the clinical course in most patients with carcinomas or sarcomas. Sometimes serological or molecular markers are used as prediction markers, but there has been no reliable marker for chondroid tumor diagnosis. Clinical and radiological, but not histological features, are still used in the diagnosis and staging of chondroid tumors. During a histopathological diagnosis, it has been difficult to distinguish between benign enchondroma and low-grade chondrosarcoma. To allow for more accurate treatments, new histological biomarkers for the differential diagnosis are needed.

Methods

Twenty-eight cases of enchondromas and thirty-three cases of low-grade chondrosarcoma were selected. Thirteen cases of non-tumorous cartilage were used for the control group, who underwent artificial joint surgery for degenerative arthritis. Surgically removed tissue specimens were formalin-fixed paraffin-embedded and hematoxylin and eosin (H&E) and immunohistochemistry (IHC) stains were performed.

Results

Periostin was expressed in chondroid tumors but not in the normal cartilage. Periostin was observed via immunostaining in the cytoplasm but not in the extracellular matrix of enchondroma tissue, and was observed in the cytoplasm and extracellular matrix of low-grade chondrosarcoma. The sensitivity and specificity of these stains were 93.9% and 96.4%, respectively.

Conclusions

Based on these results, we suggest that periostin could be used as a novel prognostic marker to distinguish between enchondroma and low-grade chondrosarcoma.