Aims. Our aim was to develop and validate nomograms that would predict the cumulative incidence of sarcoma-specific death (CISSD) and disease progression (CIDP) in patients with localized high-grade primary central and dedifferentiated chondrosarcoma. Methods. The study population consisted of 391 patients from two international sarcoma centres (development cohort) who had undergone definitive surgery for a localized high-grade (histological grade II or III) conventional primary central chondrosarcoma or dedifferentiated chondrosarcoma. Disease progression captured the first event of either metastasis or local recurrence. An independent cohort of 221 patients from three additional hospitals was used for external validation. Two nomograms were internally and externally validated for discrimination (c-index) and calibration plot. Results. In the development cohort, the CISSD at ten years was 32.9% (95% confidence interval (CI) 19.8% to 38.4%). Age at diagnosis, grade, and surgical margin were found to have significant effects on CISSD and CIDP in multivariate analyses. Maximum tumour diameter was also significantly associated with CISSD. In the development cohort, the c-indices for CISSD and CIDP at five years were 0.743 (95% CI 0.700 to 0.819) and 0.761 (95% CI 0.713 to 0.800), respectively. When applied to the validation cohort, the c-indices for CISSD and CIDP at five years were 0.839 (95% CI 0.763 to 0.916) and 0.749 (95% CI 0.672 to 0.825), respectively. The calibration plots for these two nomograms demonstrated good fit. Conclusion. Our nomograms performed well on internal and external validation and can be used to predict CISSD and CIDP after resection of localized high-grade conventional primary central and dedifferentiated chondrosarcomas. They provide a new tool with which clinicians can assess and advise individual patients about their prognosis. Cite this article: Bone Joint J 2020;102-B(12):1752–1759

Dedifferentiated chondrosarcoma is a rare, highly malignant variant of chondrosarcoma in which a high-grade spindle-cell sarcoma coexists with a lower-grade chondroid tumour. We have reviewed our experience with this neoplasm in 22 patients, all of whom were treated using modern oncological principles of planned resection and chemotherapy. Despite this the median survival was under nine months and only 18% were alive at five years. Those patients who received chemotherapy, and in whom wide margins of excision were achieved at operation, did best. It is essential to have an accurate preoperative diagnosis in order to plan treatment which may offer a better prospect of cure.

Aims. The Birmingham Orthopaedic Oncology Meeting (BOOM), held in January 2024, convened 309 delegates from 53 countries to discuss and refine 21 consensus statements on the optimal management of chondrosarcoma. Methods. With representation from Europe (43%; n = 133), North America (17%; n = 53), South America (16%; n = 49), Asia (13%; n = 40), Australasia (5%; n = 16), the Middle East (4%; n = 12), and Africa (2%; n = 6), the combined experience of treating bone sarcomas among attendees totalled approximately 30,000 cases annually, equivalent to 66 years of experience in the UK alone. The meeting’s process began with the formation of a local organizing committee, regional leads, and a scientific committee comprising representatives from 150 specialist units across 47 countries. Supported by major orthopaedic oncology organizations, the meeting used a modified Delphi process to develop consensus statements through online questionnaires, thematic groupings, narrative reviews, and anonymous pre-meeting polling. Results. Strong (> 80%) consensus was achieved on 19 out of 21 statements, reflecting agreement among delegates. Key areas of consensus included the role of radiology in diagnosis and surveillance, the management of locally recurrent disease, and the treatment of dedifferentiated chondrosarcoma. Notably, there was agreement that routine chemotherapy has no role in chondrosarcoma treatment, and radiological surveillance is safe for intraosseous chondrosarcomas. Despite the overall consensus, areas of controversy remain, particularly regarding the treatment of atypical cartilage tumours and surgical margins. These unresolved issues underscore the need for further research and collaboration within the orthopaedic oncology community. Conclusion. BOOM represents the largest global consensus meeting in orthopaedic oncology, providing valuable guidance for clinicians managing chondrosarcoma worldwide. The consensus statements offer a reference for clinical practice, highlight key research priorities, and aim to improve patient outcomes on a global scale. Cite this article: Bone Joint J 2025;107-B(2):246–252

Cartilage lesions vary in the spectrum from benign enchondromas to highly malignant dedifferentiated chondrosarcomas. From the treatment perspective, enchondromas are observed, Grade 1 chondrosarcomas are curetted like aggressive benign tumors, and rest are resected like other sarcomas. Although biopsy for tissue diagnosis is the gold standard for diagnosis and grade determination in chondrosarcoma, tumor heterogeneity limits the grading in patients following a biopsy. In the absence of definite pre-treatment grading, a surgeon is therefore often in a dilemma when deciding the best treatment option. Radiology has identified aggressive features and aggressiveness scores have been used to try and grade these tumors based on the imaging characteristics but there have been very few published reports with a uniform group and large number of cases to derive a consistent scoring and correlation. The authors asked these study questions :(1) Does Radiology Aggressiveness and its Score correlate with the grade of chondrosarcoma? (2) Can a cut off Radiology Agressiveness Score value be used to guide the clinician and add value to needle biopsy information in offering histological grade dependent management?. A retrospective analysis of patients with long bone extremity intraosseous primary chondrosarcomas were correlated with the final histology grade for the operated patients and Radiological parameters with 9 parameters identified a priori and from published literature (radiology aggressiveness scores - RAS) were evaluated and tabulated. 137 patients were identified and 2 patients were eliminated for prior surgical intervention. All patients had tissue diagnosis available and pre-treatment local radiology investigations (radiographs and/or CT scans and MRI scans) to define the RAS parameters. Spearman correlation has indicated that there was a significant positive association between RAS and final histology grading of long bone primary intraosseous chondrosarcomas. We expect higher RAS values will provide grading information in patients with inconclusive pre-surgery biopsy to tumor grades and aid in correct grade dependant surgical management of the lesion. Prediction of dedifferentiated chondrosarcoma from higher RAS will be attempted and a correlation to obtain a RAS cut off, although this may be challenging to achieve due to the overlap of features across the intermediate grade, high grade and dedifferentiated grades. Radiology Aggressiveness correlates with the histologic grade in long bone extremity primary chondrosarcomas and the correlation of radiology and biopsy can aid in treatment planning by guiding us towards a low-grade neoplasm which may be dealt with intralesional extended curettage or high-grade lesion which need to be resected. Standalone RAS may not solve the grading dilemma of primary long bone intraosseous chondrosarcomas as the need for tissue diagnosis for confirming atypical cartilaginous neoplasm cannot be eliminated, however in the event of a needle biopsy grade or inconclusive open biopsy it may guide us towards a correlational diagnosis along with radiology and pathology for grade based management of the chondrosarcoma

The influence of advancements in imaging and chemotherapy on patient with dedifferentiated chondrosarcoma was determined. There were forty-two cases in which twenty-seven patients received adjuvant therapy. Median survival was eight months and five-year survival was 4.8%. There was no statistical difference (p=0.62) in survival between patients who did and did not receive chemotherapy, had wide versus radical resection, or had limb sparing versus sacrificing procedures. There were no statistically significant differences between patients treated prior to 1986 and those subsequently. Despite advances, dedifferentiated chondrosarcoma continues to carry a poor prognosis. The routine adjuvant chemotherapy in this population should be questioned. The long-term survival for patients that presented with dedifferentiated chondrosarcoma has historically been poor. A large clinical series has not been analyzed in the era of modern diagnostic and treatment modalities. The current study was performed to look at the influence of advancements in imaging and chemotherapy on patient outcome. A retrospective chart review of all cases of patients presenting with dedifferentiated chondrosarcoma at our institution from 1984–2000 was performed. This was done as an extension to a study published in 1986 prior to the era of modern chemotherapy. There were forty-two cases in twenty-five men and seventeen women of average age fifty-six (range twenty-four-eighty-three years). MSTS grades at presentation were IIA(5), IIB(27), and III(10). Three patients underwent biopsy only, nineteen had limb sacrificing surgery, and twenty had limb sparing procedures. Surgical margins were intralesional in three, marginal in two, wide in twenty, and radical in fourteen. Twenty-seven patients received adjuvant therapy (twenty-two chemotherapy only, two radiotherapy only, three combined therapy). Median survival was eight months and five-year survival was 4.8%. There was no statistical difference (p=0.62) in survival between patients who did and did not receive chemotherapy, had wide versus radical resection, or had limb sparing versus sacrificing procedures. There were no statistically significant differences between patients treated prior to 1986 and those subsequently. Despite advances in diagnostic modalities, surgical treatments, and adjuvant therapies, dedifferentiated chondrosarcoma continues to carry a poor prognosis. The routine use of current adjuvant chemotherapy and its inherent risks and benefits in this population should be questioned

Background: And Aims Pathological fractures of the proximal femur due to primary bone sarcomas are difficult to treat. The aim of the study was to assess the factors determining the outcomes following pathological fractures of the proximal femur due to primary bone sarcomas. Methods: 93 patients with a pathological fracture of the proximal femur due to primary bone sarcomas were studied. The patient, tumour and treatment factors in relation to overall survival were analysed. Results: There were 55 male and 38 female patients. The mean age was 47 years. The diagnoses were Chondrosarcoma -34, Osteosarcoma – 21, spindle cell sarcoma – 25, Ewing’s sarcoma -13. 74 patients had a pathological fracture at diagnosis and 19 patients had a fracture after the diagnosis. 17 patients had metastases at diagnosis. 24 patients had an intracapsular fracture. Limb salvage was possible in 60 patients (65%), 18 patients had an amputation and 15 patients had palliative treatment. 27% of the patients were referred after an unplanned surgery. The mean follow up was 49 months [range 0–302]. Twenty one patients [23%] had a local recurrence -10 patients had a diagnosis of chondrosarcoma, four patients had osteosarcoma and seven had spindle cell sarcoma. The overall five years survival was 37% [Ewing’s sarcoma 60%, Chondrosarcoma 57%, spindle cell sarcoma 28%, osteosarcoma 13% and dedifferentiated Chondrosarcoma 0% (p-0.002)]. Metastasis at diagnosis was a significant factor (p-0.04) affecting survival. Conclusion: We conclude that a pathological fracture of the proximal femur due to osteosarcoma and dedifferentiated chondrosarcoma. carry a poor prognosis

Purpose: In our records on bone tumours, secondary chondrosarcomas account for slightly less than 15% of all chondrosarcomas (20/150). The presentation is quite variable making diagnosis relatively difficult. We reviewed our experience to evaluate diagnosis, frequency, and prognosis. Material and methods: From 1981 to January 2002, we had 20 chondrosarcomas which developed on pre-existing lesions: solitary exostoses (n=11), solitary chondroma (n=1), multiple exostosis (n=6), multiple enchondromatosis (n=2). Localisations were: pelvis (n=9), femur (n=3), humerus (n=2), tibia (n=3), spine (n=2), scapula (n=1). Histological classification was: grade I (n=7), grade II (n=9), grade III (n=1), and dedifferentiated sarcoma (n=3). Surgery was performed in all patients, alone for grade I and II chondrosarcoma, in association with chemotherapy (n=3) and radiotherapy (n=1) in three patients with dedifferentiated sarcoma. Results and prognostic factors: At last follow-up (mean 9 years 10 months), five patients had died after local recurrence (n=3) or metastatic dissemination (n=2). The other fifteen patients were living (mean follow-up 155 months). The main prognostic factor was histological grade of chondrosarcoma. All patients with grade I chondrosarcoma (n=7) survived versus only two-thirds of those with grade II chondrosarcoma and half (2/4) of those with grade III or dedifferentiated chondrosarcoma. The second prognostic factor was initial management. Inadequate care initially led to misdiagnosis or delayed diagnosis (n=4), local recurrence (n=3) and loss of chance of survival (n=3). Grade I chondrosarcoma was occasionally taken for benign exostosis despite a cartilage cuff measuring more than 1 cm, normally a sign of chondrosarcoma. Conclusion: 1. Because of the severity of secondary dedifferentiated chondrosarcoma, resection should be performed in adults presenting exostosis with a large residual cartilage cuff, particularly in high-risk locations (pelvis). 2. Because of the difficulty in recognising the histological features of grade I chondrosarcoma, the diagnosis of degeneration should be retained in adults if the cartilage cuff exceeds 1 cm. Lesions are suspicious if the cartilage cuff exceeds 5 mm

Chondrosarcomas are uncommon primary malignant cartilaginous tumours, even less common in spine. Surgical excision is the only mode of successful treatment as these tumours are resistant to conventional chemotherapy and radiation therapy. We share our experience of 22 cases of chondrosarcomas of the spine with special reference to their recurrence and survival. We identified 20 conventional and 2 dedifferentiated chondrosarcomas from the Scottish Bone Tumour Registry database between 1964 and 2009. Radiology and histopathology were documented. The mean follow-up was 5.2 years. There were 14 men and 8 women with a mean age of 50.1 years. There were 7 under the age of 40 years (31.8%). The majority of lesions occurred in the thoracic spine (16), followed by sacrum (3), lumbar (2) and cervical spine (1). The overall local recurrence rate was 45.4% (10/22 cases-once in 5, twice in 2 and thrice in 3 patients). Four patients presented with pulmonary metastases leading to death. The estimated overall 5- and 10-year survival rates were 31.8% and 18.1% respectively. We found that 1/3. rd. of chondrosarcomas of the spine occured below 40 years of age and 3/4. th. in the thoracic spine. Every other case was associated with local recurrence with a 32% 5-year and 18% 10-year survival rates

Seven patients who had malignant proximal femoral tumours were selected for resection and limb salvage with a modular megaprosthesis. Histopathological diagnosis confirmed one solitary bone metastasis from renal cell carcinoma, one dedifferentiated chondrosarcoma, two primary non-Hodgkin lymphomas non-responsive to adjuvant chemo- and radiotherapy and three low-grade chondrosarcomas. The mean age at the time of surgery was 53.5 years. Post-operative survival averaged 54.5 months. The mean functional status score was satisfactory. There was no local tumour recurrence or dislocation of the prosthesis. There were one superficial wound infection and one post-surgical haematoma. Care must be taken in selecting patients to for resection of the proximal femur and implantation of modular megaprostheses. We reserve such treatment only for tumours that, because of the histopathological diagnosis and spread, chemotherapy or radiotherapy alone is not enough. Modular megaprosthesis is currently the method of choice in the treatment of malignant proximal femoral tumours. With this implant joint function can be restored after wide resection, too, offering a valid alternative to the bony massive allografts that are characterised by a high rate of complications and failure

Dedifferentiated chondrosarcoma is a rare but highly malignant manifestation that can occasionally arise in patients with cartilage tumours. There remains uncertainty as to the best treatment for this condition and in particular whether chemotherapy may have a role in improving prognosis. Members of EMSOS were invited to contribute data on patients, tumours, treatment and outcomes of patients with dedifferentiated chondrosarcoma. Eight centres contributed data on 317 patients from 7 countries. The mean age was 59 (range 15 to 89) and the most common site was the femur (46%) followed by the pelvis (28%). 25% of patients presented with a pathological fracture and the most common high grade component identified was MFH. 23% had metastases at diagnosis and these patients had a median survival of 5 months. 30% of patients received chemotherapy, with 47% under 60 having chemotherapy compared with 10% over 60. One third of this group had neoadjuvant chemotherapy and the rest had adjuvant reatment. 88% had surgery with limb salvage in 80% of this group. The overall survival was 38% at 2 years and 24% at 5 years but in patients without metastases at diagnosis these figures were 44% and 28% respectively. Poor prognostic factors for survival were: metastases at diagnosis, amputation or no operation, local recurrence, age over 60 and pathological fracture at presentation. We were unable to identify any group in whom chemotherapy appeared to have a survival benefit. Dedifferentiated chondrosarcoma carries a dismal prognosis. Although 30% of patients received chemotherapy in this study we were not able to prove that it improved survival. Early diagnosis and complete surgical excision still offer the best prognosis for this condition

Chondrosarcoma is treated with respect by oncology surgeons, given that it is relatively resistant to chemotherapy and radiotherapy. The aim was to study the outcomes of surgery for chondrosarcoma and determine the role of initial surgical margins and local recurrence on outcome. Electronic patient records were retrieved on all patients seen with chondrosarcoma of bone with a minimum of two years follow up. A total of 532 patients were seen with Chondrosarcoma between 1970 and 2006. Patients were excluded if they had initial treatment in another unit (20 patients), a subdiagnosis of dedifferentiated chondrosarcoma (due to very poor prognosis, 43 patients), metastases at presentation (30 patients), if they presented with disseminated metastases prior to local recurrence (12 patients) or were not offered surgery, leaving 402 patients in the study group. The mean age was 48 years old (range 6–89 years) with the most commonly sites of presentation being in the pelvis in 132 patients (29%), proximal femur in 81 patients (18%), distal femur in 40 patients (9%) and proximal humerus in 40 patients (9%). Grade at presentation was grade 1 in 44%, grade 2 in 44% and grade 3 in 12%. Surgical margins were radical in 3%, wide in 44%, marginal in 29%, planned incisional in 13% and unplanned incisional in 11%. Local recurrence occurred in 87 patients (22%). Local recurrence rates were significantly different for surgical margins on Fisher exact testing (p=0.003), which held true even when stratified by presenting grade of tumour. Surgery for local control was successful in 62% of cases. Complex relationships exist between surgical margins, local recurrence and survival. Long term survival is possible in 1/3 patients who have local recurrence in intermediate and high grade chondrosarcomas and therefore ever effort should be made to regain local control following local recurrence

EUROpean Bone Over 40 Sarcoma Study (EURO-B.O.S.S.) is the first prospective multicenter international study for patients 41–65 year old with high-grade bone sarcoma. Patients with HG Osteosarcoma (OS), HG sarcoma NOS (S), Fibrosarcoma, MFH, Leiomyosarcoma, Dedifferentiated Chondrosarcoma (DCh) were included. Chemotherapy: Combinations of cisplatin/doxorubicin (CDP 100mg/m2/ADM 60mg/m2), ifosfamide/CDP(IFO 6g/m2/CDP 100mg/m2) and IFO/ADM (IFO 6g/m2/ADM 60mg/m2) were repeated three times (9 cycles). Surgery was planned after 3 cycles. Methotrexate (8g/m2) was postoperatively added in poor responders. Immediate surgery was allowed and 9 cycles with CDP, ADM, IFO were postoperatively given. At December 2007, 140 patients were registered (median age 51 years). OS (51%), S (16%), and DCh (11%) were the more frequent histotypes. Synchronous metastases in 30 (21%) patients, central location of tumor in 45(32%).Surgical complete remission (SCR) was achieved in 84% of patients, (localized 91%, meta-static 37%) without difference among the histology groups. One surgical-related and one chemotherapy-related death were reported. Grade4 WBC and PLT incidence was 55% and 17%.Renal toxicity and peripheral neurotoxicity were reported in 16% and 20% of patients. With a median follow-up of 25 months (4–68) 3 year OS was 58% (95%CI 48–68%) [7% (95%CI 0–19%) without SCR]. In patients with SCR, 3-year OS and EFS were 46% (95%CI 9–83%) and 0% in case of synchronous metastases and 69% (95%CI58–80%) and 45% (95%CI33–57%) for localized patients; 50% (95%CI 29–71%) and 40% (95%CI 20–59%) for patients with central tumor, 73% (95%CI61–85%) and 44% (95%CI31–57%) for those with extremity tumor; 68% (95%CI 52–83%) and 46% (95%CI 32–54%) for OS, 64% (95%CI 42–85%) and 48% (95%CI 25–71%) for S, 48% (95%CI 13–82%) and 27% (95%CI 1–54%) for DCh. The protocol is feasible, but the chemotherapy-related toxicity is remarkable. Surgical complete remission is the main factor influencing survival. Central location and synchronous metastases are negative prognostic factors, but 50% 3-year OS can be achieved with aggressive local and systemic treatment. Osteosarcoma and high-grade sarcoma NOS benefit from chemotherapy more than patients with dedifferentiated chondrosarcoma

Introduction: Chondrosarcoma has always been treated with respect by oncology surgeons, given that it is relatively resistant to chemotherapy and radiotherapy. The importance of the adequacy of surgical resection margins has been previously reported, however, the aim of the study was to study the outcomes of surgery for Chondrosarcoma and determine the role of initial surgical margins and local recurrence on final outcome. Methods: Electronic patient records were retrieved on all patients seen at a tertiary referral musculoskeletal oncology centre with Chondrosarcoma of bone with a minimum of 2 years follow up. A total of 532 patients were seen with Chondrosarcoma between 1970 and 1/1/2006. Patients were excluded if they had initial treatment in another unit (20 patients), a subdiagnosis of dedifferentiated Chondrosarcoma (due to very poor prognosis, 43 patients), metastases at presentation (6 patients) and if they presented with disseminated metastases prior to local recurrence (12 patients). This left 451 patients in the study group and the clinicopathological records were reviewed on these patients. Results: Of the 451 patients, the mean age was 48 years old at diagnosis (range 6–89 years) with the most commonly sites of presentation being in the pelvis in 132 patients (29%), proximal femur in 81 patients (18%), distal femur in 40 patients (9%) and proximal humerus in 40 patients (9%). Grade at presentation was grade 1 in 44%, grade 2 in 44% and grade 3 in 12%. Surgical margins were wide in 45%, marginal in 28% and incisional (including curettage procedures) in 27%. Local recurrence occurred in 88 patients (19.5%). Local recurrence rates were significantly different for surgical margins on Fisher exact testing (p=0.003), which held true even when stratified by presenting grade of tumour. Local recurrence occurred at a mean of 2.8 years, however, 12.5% occurred more than 5 years from diagnosis. There was a significant difference in survival compared between those patients with local recurrent disease and those without on Kaplan Meier analysis; 10 year survival for those without recurrence was 73.1% compared to 41% for those with local recurrence(p< 0.0001, Logrank). On cox regression analysis significant factors affecting survival were pelvic location (p=0.004), local recurrence (p=0.007), age at presentation (p=0.01), marginal margins (p=0.04) and initial tumour grade (p=0.043). There was no significant difference between survival and initial surgical margin when stratified by grade of tumour, possibly as further surgery to improve adequacy of margins. Further sub-analysis is being performed. Conclusions: There is a complex relationship between surgical margins, local recurrence and margins. It appears that long term survival is possible in approximately 1/3 patients who have local recurrence in intermediate and high grade chondrosarcomas and therefore ever effort should be made to regain local control following local recurrence

Aims

The aim of this study was to investigate the safety and efficacy of 3D-printed modular prostheses in patients who underwent joint-sparing limb salvage surgery (JSLSS) for malignant femoral diaphyseal bone tumours.

The October 2024 Oncology Roundup³⁶⁰ looks at: Composite reconstruction: is it the answer for pelvic resections?; Can the cartilaginous thickness determine the risk of malignancy in pelvic cartilaginous tumours, and how accurate is the preoperative biopsy of these tumours?; Incidence and survival outcomes of patients with high-grade appendicular bone sarcoma and isolated regional lymph node metastasis; Improved metastatic-free survival after systematic re-excision following complete macroscopic unplanned excision of limb or trunk soft-tissue sarcoma; UK guidelines for the management of soft-tissue sarcomas; Current management of desmoid tumours: a review.

Aims

Chondrosarcoma is the second most common primary sarcoma of bone: conventional chondrosarcoma accounts for 85% of all cases. Conventional chondrosarcoma may be central or peripheral. Most studies group central and peripheral chondrosarcomas together, although there is growing evidence that their clinical behaviour and prognosis differ. The aims of this study were to analyze any differences in characteristics between central and peripheral chondrosarcomas and to investigate the incidence and role of different syndromes.