From the archives of the AFIP: imaging of primary chondrosarcoma: radiologic-pathologic correlation

Targeted treatment of chondrosarcoma with a bacteriophage-based particle delivering a secreted tumor necrosis factor-related apoptosis-inducing ligand

Chondrosarcoma (CS) is a malignant cartilage-forming bone tumor that is inherently resistant to chemotherapy and radiotherapy, leaving surgery as the only treatment option. We have designed a tumor-targeted bacteriophage (phage)-derived particle (PDP), for targeted systemic delivery of cytokine-encoding transgenes to solid tumors. Phage has no intrinsic tropism for mammalian cells; therefore, it was engineered to display a double cyclic RGD4C ligand on the capsid to target tumors. To induce cancer cell death, we constructed a transgene cassette expressing a secreted form of the cytokine tumor necrosis factor-related apoptosis-inducing ligand (sTRAIL). We detected high expression of αvβ3 and αvβ5 integrin receptors of the RGD4C ligand, and of the TRAIL receptor-2 in human CS cells (SW1353), but not in primary normal chondrocytes. The RGD4C.PDP-Luc particle carrying a luciferase reporter gene, Luc, effectively and selectively mediated gene delivery to SW1353 cells, but not primary chondrocytes. Transduction of SW1353 cells with RGD4C.PDP-sTRAIL encoding a human sTRAIL, resulted in the expression of TRAIL and subsequent cell death without harming the normal chondrocytes. Intravenous administration of RGD4C.PDP-sTRAIL to mice with established human CS resulted in a decrease in tumor size and tumor viability. Altogether, RGD4C.PDP-sTRAIL can be used to target systemic treatment of CS with the sTRAIL.

Diagnostic performance and inter-reader reliability of bone reporting and data system (Bone-RADS) on computed tomography

OBJECTIVE

To evaluate the diagnostic performance and inter-reader reliability of the Bone Reporting and Data System (Bone-RADS) for solitary bone lesions on CT.

MATERIALS AND METHODS

This retrospective analysis included 179 patients (mean age, 56 ± 18 years; 94 men) who underwent bone biopsies between March 2005 and September 2021. Patients with solitary bone lesions on CT and sufficient histopathology results were included. Two radiologists categorized the bone lesions using the Bone-RADS (1, benign; 4, malignant). The diagnostic performance of the Bone-RADS was calculated using histopathology results as a standard reference. Inter-reader reliability was calculated.

RESULTS

Bone lesions were categorized into two groups: 103 lucent (pathology: 34 benign, 12 intermediate, 54 malignant, and 3 osteomyelitis) and 76 sclerotic/mixed (pathology: 46 benign, 2 intermediate, 26 malignant, and 2 osteomyelitis) lesions. The Bone-RADS for lucent lesions had sensitivities of 95% and 82%, specificities of 11% and 11%, and accuracies of 57% and 50% for readers 1 and 2, respectively. The Bone-RADS for sclerotic/mixed lesions had sensitivities of 75% and 68%, specificities of 27% and 27%, and accuracies of 45% and 42% for readers 1 and 2, respectively. Inter-reader reliability was moderate to very good (κ = 0.744, overall; 0.565, lucent lesions; and 0.851, sclerotic/mixed lesions).

CONCLUSION

Bone-RADS has a high sensitivity for evaluating malignancy in lucent bone lesions and good inter-reader reliability. However, it has poor specificity and accuracy for both lucent and sclerotic/mixed lesions. A possible explanation is that proposed algorithms heavily depend on clinical features such as pain and history of malignancy.

Neoplastic and Non-neoplastic Bone Lesions of the Knee

Numerous anatomical variants are described around the knee, many of which look like bony lesions, so it is important to know them to avoid unnecessary complementary tests and inadequate management. Likewise, several alterations in relation to normal development can also simulate bone lesions.However, numerous pathologic processes frequently affect the knee, including traumatic, inflammatory, infectious, and tumor pathology. Many of these entities show typical radiologic features that facilitate their diagnosis. In other cases, a correct differential diagnosis is necessary for proper clinical management.Despite the availability of increasingly advanced imaging techniques, plain radiography is still the technique of choice in the initial study of many of these pathologies. This article reviews the radiologic characteristics of tumor and nontumor lesions that may appear around the knee to make a correct diagnosis and avoid unnecessary complementary radiologic examinations and inadequate clinical management.

A CT-based radiomics nomogram for predicting histologic grade and outcome in chondrosarcoma

OBJECTIVE

The preoperative identification of tumor grade in chondrosarcoma (CS) is crucial for devising effective treatment strategies and predicting outcomes. The study aims to build and validate a CT-based radiomics nomogram (RN) for the preoperative identification of tumor grade in CS, and to evaluate the correlation between the RN-predicted tumor grade and postoperative outcome.

METHODS

A total of 196 patients (139 in the training cohort and 57 in the external validation cohort) were derived from three different centers. A clinical model, radiomics signature (RS) and RN (which combines significant clinical factors and RS) were developed and validated to assess their ability to distinguish low-grade from high-grade CS with area under the curve (AUC). Additionally, Kaplan-Meier survival analysis was applied to examine the association between RN-predicted tumor grade and recurrence-free survival (RFS) of CS. The predictive accuracy of the RN was evaluated using Harrell's concordance index (C-index), hazard ratio (HR) and AUC.

RESULTS

Size, endosteal scalloping and active periostitis were selected to build the clinical model. Three radiomics features, based on CT images, were selected to construct the RS. Both the RN (AUC, 0.842) and RS (AUC, 0.835) were superior to the clinical model (AUC, 0.776) in the validation set (P = 0.003, 0.040, respectively). A correlation between Nomogram score (Nomo-score, derived from RN) and RFS was observed through Kaplan-Meier survival analysis in the training and test cohorts (log-rank P < 0.050). Patients with high Nomo-score tumors were 2.669 times more likely to suffer recurrence than those with low Nomo-score tumors (HR, 2.669, P < 0.001).

CONCLUSIONS

The CT-based RN performed well in predicting both the histologic grade and outcome of CS.

CT and MR imaging findings of head and neck chondrosarcoma

OBJECTIVES

This study investigated the imaging features of head and neck chondrosarcoma (HNCS) according to its origin and pathologic subtype.

METHODS

Patients who were pathologically diagnosed with HNCS between January 2000 and April 2022 were retrospectively reviewed. Lesions were classified based on their origin and pathologic subtype. The size and margin were evaluated on the image. Internal calcification and the effects on adjacent bone were assessed using computed tomography (CT) images, while signal intensity and contrast enhancement patterns were analyzed using magnetic resonance (MR) imaging.

RESULTS

Thirteen HNCSs were included in this study: 8 bone tumors (61.5%) and 5 soft tissue tumors (38.5%). The bone tumors were pathologically diagnosed as conventional (n = 5) and mesenchymal type (n = 3). Soft tissue tumors were defined as myxoid type. The main symptoms were swelling (90.9%) and pain (72.7%). The lesions measured 4.5 cm on average. The margins showed benign and well-defined except for the mesenchymal type. On CT, most bone tumors (75%) showed internal calcification with remodeling or destruction of the adjacent bone. No soft tissue tumors, except one case, showed internal calcification or destruction of the adjacent bone. MR imaging features were non-specific (T2 high signal intensity and contrast enhancement).

CONCLUSIONS

HCNS showed various imaging findings according to their origin and pathologic subtype. HNCS should be differentiated if a bone tumor shows internal calcification and affects the adjacent bone. When diagnosing slow-growing soft tissue tumors, even if low possibility, HNCS should be considered.

X-rays radiomics-based machine learning classification of atypical cartilaginous tumour and high-grade chondrosarcoma of long bones

BACKGROUND

Atypical cartilaginous tumour (ACT) and high-grade chondrosarcoma (CS) of long bones are respectively managed with active surveillance or curettage and wide resection. Our aim was to determine diagnostic performance of X-rays radiomics-based machine learning for classification of ACT and high-grade CS of long bones.

METHODS

This retrospective, IRB-approved study included 150 patients with surgically treated and histology-proven lesions at two tertiary bone sarcoma centres. At centre 1, the dataset was split into training (n = 71 ACT, n = 24 high-grade CS) and internal test (n = 19 ACT, n = 6 high-grade CS) cohorts, respectively, based on the date of surgery. At centre 2, the dataset constituted the external test cohort (n = 12 ACT, n = 18 high-grade CS). Manual segmentation was performed on frontal view X-rays, using MRI or CT for preliminary identification of lesion margins. After image pre-processing, radiomic features were extracted. Dimensionality reduction included stability, coefficient of variation, and mutual information analyses. In the training cohort, after class balancing, a machine learning classifier (Support Vector Machine) was automatically tuned using nested 10-fold cross-validation. Then, it was tested on both the test cohorts and compared to two musculoskeletal radiologists' performance using McNemar's test.

FINDINGS

Five radiomic features (3 morphology, 2 texture) passed dimensionality reduction. After tuning on the training cohort (AUC = 0.75), the classifier had 80%, 83%, 79% and 80%, 89%, 67% accuracy, sensitivity, and specificity in the internal (temporally independent) and external (geographically independent) test cohorts, respectively, with no difference compared to the radiologists (p ≥ 0.617).

INTERPRETATION

X-rays radiomics-based machine learning accurately differentiates between ACT and high-grade CS of long bones.

FUNDING

AIRC Investigator Grant.

A rare case report of recurrent primary intra-abdominal synovial sarcoma: An unusual manifestation

Synovial sarcomas are a rare and aggressive subtype of soft tissue sarcomas that typically affects young adults and involves the extremities. Synovial sarcoma of the kidney is a rare and aggressive tumor with a poor prognosis, accounting for only 1% of all renal tumors. The imaging features of this tumor often overlap with those of other renal tumors, and a definitive diagnosis can only be made through immunohistochemical analysis. In this case report, we present the case of a 55-year-old female with left flank pain, who was diagnosed with primary renal synovial sarcoma following a left-sided radical nephrectomy. Despite initial successful surgical intervention, restaging scans showed local recurrence and metastatic disease, which was subsequently managed with 6 cycles of chemotherapy followed by radiation therapy with palliative intent. This case underscores the importance of early detection and aggressive management of rare renal tumors to improve patient outcomes.

Extraskeletal Myxoid Chondrosarcoma of Floor of Mouth-A Rare Case Report and Review of Literature

Introduction

Chondrosarcomas are rare malignancies of the cartilage and myxoid chondrosarcoma is its variant which commonly occurs in soft tissue of extremities. Extraskeletal chondrosarcoma is a rare malignant neoplasm of bone or soft tissue origin and is characterized by the presence of spindle cells admixed with well differentiated cartilage or chondroid stroma. They are mostly radioresistant tumours and surgical resections with adequate margins is considered as the ideal treatment modality with adjuvant radiotherapy in high grade tumours and add on chemotherapy, in case of presence of poor prognostic factors.

Case Report

A 51-year-old diabetic, hypertensive female patient presented to our outpatient department with difficulty in chewing food for a duration of 6 months. On clinical examination, she had an ulceroproliferative growth involving right lower alveolus and floor of mouth. MRI face and neck with contrast showed a 4.1 × 2.9 × 4.5 cm lesion involving right lower alveolus extending to floor of mouth. Biopsy showed features of extraskeletal myxoid chondrosarcoma. She was planned for upfront surgery (Right composite resection with modified radical neck dissection with free fibula flap). Patient was stable post-surgery and was discharged in stable condition. Final histopathology report was high grade myxoid chondrosarcoma. The case was presented in tumour board and the patient was planned for adjuvant radiotherapy. She has been on regular follow up for the past 2 years and shows no signs of recurrence.

Conclusion

Extraskeletal myxoid chondrosarcoma of oral cavity is a rare entity and very few cases are reported. It is a malignant neoplasm which is diagnosed with the help of immunohistochemistry. Surgery is the ideal modality of treatment accompanied by adjuvant radiotherapy in cases of high-grade tumours.

Extraskeletal conventional chondrosarcoma of genitalia in a child- An unusual pathology for a rare tumor

INTRODUCTION AND IMPORTANCE

Chondrosarcoma is a rare malignant tumor considered as the second common sarcoma of bone following osteosarcoma. Less than 5 % of chondrosarcomas occur in children. Conventional chondrosarcoma is the most common type observed as skeletal tumors. Extraskeletal chondrosarcomas account for about 1 % of chondrosarcomas. They are almost always of myxoid or mesenchymal subtypes.

CASE PRESENTATION

A 4-year-old girl was referred with pain and palpable mass in the labia majora since 2 years of age for which she had undergone twice biopsies, reported as soft tissue enchondroma. At this time, complete excision of the lesion with negative margins was carried out. The pathology was in favor of extraskeletal chondrosarcoma of conventional type without any evidence of bone involvement.

CLINICAL DISCUSSION

Our case was a very young child with extraskeletal conventional chondrosarcoma, not reported yet in the literature. The vast majority of extraskeletal myxoid chondrosarcomas arise in the soft tissues of the extremities. The lesion in this case was located within the subcutaneous tissue of the labia majora; however, the tumor was not compatible with myxoid chondrosarcoma. Mesenchymal chondrosarcoma is another type of extraskeletal chondrosarcoma but the histopathologic patterns observed in our patient were not compatible even with the mesenchymal chondrosarcoma.

CONCLUSION

We present a unique case of extraskeletal chondrosarcoma in a child with conventional subtype which has not been reported in the literature. In addition, the lesion was assumed to arise from a previous soft tissue enchondroma of the labia majora since infancy which makes the case distinctive.

Imaging diagnosis and differential diagnosis of extraskeletal osteosarcoma

OBJECTIVE

The aim of this study was to investigate the clinical, imaging and pathological features of extraskeletal osteosarcoma (EOS) and to improve the understanding of this disease and other similar lesions.

METHODS

The data for 11 patients with pathologically confirmed extraosseous osteosarcoma, including tumour site and size and imaging and clinical manifestations, were analysed retrospectively.

RESULTS

Six patients were male (60%), and 5 were female (40%); patient age ranged from 23 to 76 years (average age 47.1 years). Among the 11 patients, 7 had clear calcifications or ossification with different morphologies, and 2 patients showed a massive mature bone tumour. MRI showed a mixed-signal mass with slightly longer T1 and T2 signals in the tumour parenchyma. Enhanced CT and MRI scans showed enhancement in the parenchyma. Ten patients had different degrees of necrosis and cystic degeneration in the mass, 2 of whom were complicated with haemorrhage, and MRI showed "fluid‒fluid level" signs. Of the 11 patients, five patients survived after surgery, and no obvious recurrence or metastasis was found on imaging examination. One patient died of lung metastasis after surgery, and 2 patients with open biopsy died of disease progression. One patient died of respiratory failure 2 months after operation. 2 patients had positive surgical margins, and 1 had lung metastasis 6 months after operation and died 19 months after operation. Another patient had recurrence 2 months after surgery.

CONCLUSION

The diagnosis of EOS requires a combination of clinical, imaging and histological examinations. Cystic degeneration and necrosis; mineralization is common, especially thick and lumpy mineralization. Extended resection is still the first choice for localized lesions. For patients with positive surgical margins or metastases, adjuvant chemoradiotherapy is needed.

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.

Chondrosarcoma With Pulmonary Metastatic Calcifications: A Case Report and Review of the Literature

A chondrosarcoma with pulmonary metastatic calcifications is a rarely reported phenomenon. This report discusses chondrosarcomas and their clinical features, diagnosis, and treatment, using as an example the case of a 55-year-old female with a right pelvic chondrosarcoma that developed over 10 years. In the last two years, the patient had increasing pulmonary findings, including pulmonary nodules, ground glass opacities, and likely pulmonary metastatic calcifications. The objective of this report is to explore chondrosarcomas and their pattern of metastatic presentation, with the hope of improving recognition of the disease and streamlining treatment.

Update of cartilaginous tumours according to the WHO classification 2020

Cartilaginous tumours are a large and heterogeneous group of neoplasms characterised by the presence of a chondroid matrix, with lobular growth and arcuate, ring-like or popcorn-like calcification patterns. MRI shows hyperintensity in T2-weighted sequences and a lobulated or septal relief in postcontrast images. In the WHO 2020 classification, chondral tumours are classified as benign, intermediate or malignant. Despite technological advances, they continue to pose a challenge for both the radiologist and the pathologist, being the main difficulty the differentiation between benign and malignant tumours, which is why they require a multidisciplinary approach. This paper describes the main changes introduced in the 2020 update, describes the imaging characteristics of the main cartilaginous tumours and provides the radiological keys to differentiate between benign and malignant tumours.

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.

Chondrosarcoma of the spine-a case report

CASE

A 73-year-old male patient presented with a 3-month history of back pain. In bone scintigraphy and the FDG PET-CT scan (fluorodeoxyglucose positron-emission computed tomography), highly suspect uptake levels were found in TH12-L1. Accordingly, an osteodestructive process was found on MRI (magnetic resonance imaging). Following a successfully performed biopsy of TH12, histologic analysis of the bone material revealed a chondrosarcoma (G1; T4N2M0). Complete resection of the tumor was successfully performed, since chondrosarcoma are resistant to radiation and chemotherapy.

CONCLUSION

As chondrosarcoma is a rare bone neoplasm, it must be considered in the differential diagnosis of lower back pain to initiate adequate treatment.

Differentiation between Chondrosarcoma and Synovial Chondromatosis of the Temporomandibular Joint Using CT and MR Imaging

BACKGROUND AND PURPOSE

Chondrosarcoma and synovial chondromatosis of the temporomandibular joint share overlapping clinical and histopathologic features. We aimed to identify CT and MR imaging features to differentiate chondrosarcoma from synovial chondromatosis of the temporomandibular joint.

MATERIALS AND METHODS

The CT and MR images of 12 and 35 patients with histopathologically confirmed chondrosarcoma and synovial chondromatosis of the temporomandibular joint, respectively, were retrospectively reviewed. Imaging features including lesion size, center, enhancement, destruction/sclerosis of surrounding bone, infiltration into the tendon of the lateral pterygoid muscle, calcification, periosteal reaction, and osteophyte formation were assessed. A comparison between chondrosarcoma and synovial chondromatosis was performed with a Student t test for quantitative variables and the Fisher exact test or linear-by-linear association test for qualitative variables. Receiver operating characteristic analysis was performed to determine the diagnostic performance for differentiation of chondrosarcoma and synovial chondromatosis based on a composite score obtained by assigning 1 point for each of 9 imaging features.

RESULTS

High-risk imaging features for chondrosarcoma were the following: lesion centered on the mandibular condyle, destruction of the mandibular condyle, no destruction/sclerosis of the articular eminence/glenoid fossa, infiltration into the tendon of the lateral pterygoid muscle, absent or stippled calcification, periosteal reaction, internal enhancement, and size of ≥30.5 mm. The best cutoff value to discriminate chondrosarcoma from synovial chondromatosis was the presence of any 4 of these high-risk imaging features, with an area under the curve of 0.986 and an accuracy of 95.8%.

CONCLUSIONS

CT and MR imaging features can distinguish chondrosarcoma from synovial chondromatosis of the temporomandibular joint with improved diagnostic performance when a subcombination of 9 imaging features is used.

Primary Benign Neoplasms of the Spine

Benign tumours comprise the majority of primary vertebral tumours, and these are often found incidentally on imaging. Nonetheless, accurate diagnosis of these benign lesions is crucial, in order to avoid misdiagnosis as more ominous malignant lesions or infection. Furthermore, some of these tumours, despite their benign nature, can have localised effects on the spine including neural compromise, or can be locally aggressive, thus necessitating active management. Haemangiomas and osteomas (enostosis) are the commonest benign tumours encountered. Others include osteoid osteoma, osteoblastoma, fibrous dysplasia, osteochondroma, chondroblastoma, haemangioma, simple bone cysts, aneurysmal bone cysts, giant cell tumours, eosinophilic granuloma and notochordal rests. The majority of lesions are asymptomatic; however, locally aggressive lesions (such as aneurysmal bone cysts or giant cell tumours) can present with nonspecific symptoms, such as back pain, neurological deficits and spinal instability, which may be indistinguishable from more commonly encountered mechanical back pain or malignant lesions including metastases. Hence, imaging, including radiography, computed tomography (CT) and magnetic resonance imaging (MRI), plays a critical role in diagnosis. Generally, most incidental or asymptomatic regions are conservatively managed or may not require any follow-up, while symptomatic or locally aggressive lesions warrant active interventions, which include surgical resection or percutaneous treatment techniques. Due to advances in interventional radiology techniques in recent years, percutaneous minimally invasive techniques such as radiofrequency ablation, sclerotherapy and cryoablation have played an increasing role in the management of these tumours with favourable outcomes. The different types of primary benign vertebral tumours will be discussed in this article with an emphasis on pertinent imaging features.

Beyond the bones: Extraskeletal osteosarcoma of the thigh

Extraskeletal osteosarcoma (ESOS) is a rare malignant mesenchymal soft tissue tumor that usually arises in the lower extremities. It is typically a high-grade malignancy that represents only around 1%-2% of all soft tissue sarcomas and 2%-4% of all osteosarcomas. In this report, we describe a case of a 67-year-old female who presented with a 4-day history of a painless lump in her posterior right thigh. Workup utilizing different imaging modalities yielded a diagnosis of ESOS. The radiologic features of ESOS, as well as the current treatment paradigm and prognosis of this rare malignancy, will be discussed based on a review of the literature.

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.

Celastrol as an emerging anticancer agent: Current status, challenges and therapeutic strategies

Celastrol is a pentacyclic triterpenoid extracted from the traditional Chinese medicine Tripterygium wilfordii Hook F., which has multiple pharmacological activities. In particular, modern pharmacological studies have demonstrated that celastrol exhibits significant broad-spectrum anticancer activities in the treatment of a variety of cancers, including lung cancer, liver cancer, colorectal cancer, hematological malignancies, gastric cancer, prostate cancer, renal carcinoma, breast cancer, bone tumor, brain tumor, cervical cancer, and ovarian cancer. Therefore, by searching the databases of PubMed, Web of Science, ScienceDirect and CNKI, this review comprehensively summarizes the molecular mechanisms of the anticancer effects of celastrol. According to the data, the anticancer effects of celastrol can be mediated by inhibiting tumor cell proliferation, migration and invasion, inducing cell apoptosis, suppressing autophagy, hindering angiogenesis and inhibiting tumor metastasis. More importantly, PI3K/Akt/mTOR, Bcl-2/Bax-caspase 9/3, EGFR, ROS/JNK, NF-κB, STAT3, JNK/Nrf2/HO-1, VEGF, AR/miR-101, HSF1-LKB1-AMPKα-YAP, Wnt/β-catenin and CIP2A/c-MYC signaling pathways are considered as important molecular targets for the anticancer effects of celastrol. Subsequently, studies of its toxicity and pharmacokinetic properties showed that celastrol has some adverse effects, low oral bioavailability and a narrow therapeutic window. In addition, the current challenges of celastrol and the corresponding therapeutic strategies are also discussed, thus providing a theoretical basis for the development and application of celastrol in the clinic.

A Retrospective Multi-Institutional Cohort Analysis of Clinical Characteristics and Outcomes in Dedifferentiated Chondrosarcoma

BACKGROUND

Dedifferentiated chondrosarcoma (DDCS) is a rare subset of chondrosarcoma. It is an aggressive neoplasm characterized by a high rate of recurrent and metastatic disease with overall poor outcomes. Systemic therapy is often used to treat DDCS; however, the optimal regimen and timing are not well defined, with current guidelines recommending following osteosarcoma protocols.

METHODS

We conducted a multi-institutional retrospective analysis of clinical characteristics and outcomes of patients with DDCS. Between 1 January 2004 and 1 January 2022, the databases from five academic sarcoma centers were reviewed. Patient and tumor factors, including age, sex, tumor size, site, location, the treatments rendered, and survival outcomes, were collected.

RESULTS

Seventy-four patients were identified and included in the analysis. Most patients presented with localized disease. Surgical resection was the mainstay of therapy. Chemotherapy was used predominantly in the metastatic setting. Partial responses were low (n = 4; 9%) and occurred upon treatment with doxorubicin with cisplatin or ifosfamide and single-agent pembrolizumab. For all other regimens, stable disease was the best response. Prolonged stable disease occurred with the use of pazopanib and immune checkpoint inhibitors.

CONCLUSIONS

DDCS has poor outcomes and conventional chemotherapy has limited benefit. Future studies should focus on defining the possible role of molecularly targeted therapies and immunotherapy in the treatment of DDCS.

Chondroid Tumors: Review of Salient Imaging Features and Update on the WHO Classification

Chondrogenic tumors are typically well recognized on radiographs, but differentiation between benign and malignant cartilaginous lesions can be difficult both for the radiologist and for the pathologist. Diagnosis is based on a combination of clinical, radiological and histological findings. While treatment of benign lesions does not require surgery, the only curative treatment for chondrosarcoma is resection. This article (1) emphasizes the update of the WHO classification and its diagnostic and clinical effects; (2) describes the imaging features of the various types of cartilaginous tumors, highlighting findings that can help differentiate benign from malignant lesions; (3) presents differential diagnoses; and (4) provides pathologic correlation. We attempt to offer valuable clues in the approach to this vast entity.

Molecular In-Depth Characterization of Chondrosarcoma for Current and Future Targeted Therapies

Chondrosarcoma (CHS) are heterogenous, but as a whole, represent the second most common primary malignant bone tumor entity. Although knowledge on tumor biology has grown exponentially during the past few decades, surgical resection remains the gold standard for the treatment of these tumors, while radiation and differentiated chemotherapy do not result in sufficient cancer control. An in-depth molecular characterization of CHS reveals significant differences compared to tumors of epithelial origin. Genetically, CHS are heterogenous, but there is no characteristic mutation defining CHS, and yet, IDH1 and IDH2 mutations are frequent. Hypovascularization, extracellular matrix composition of collagen, proteoglycans, and hyaluronan create a mechanical barrier for tumor suppressive immune cells. Comparatively low proliferation rates, MDR-1 expression and an acidic tumor microenvironment further limit therapeutic options in CHS. Future advances in CHS therapy depend on the further characterization of CHS, especially the tumor immune microenvironment, for improved and better targeted therapies.

Machine learning and magnetic resonance imaging: Differentiating benign from malignant osseous tumors

Radiomics and machine learning applied to the isolated cartilaginous bone lesion on magnetic resonance imaging (MRI) is increasingly useful to distinguish malignant versus benign bone lesions, to determine whether repetitive imaging over time, to determine dynamic expansion, or immediate excisional biopsy are indicated.

Solitary osteochondromas in paleo-oncology: A case report from 4th-century BCE Pontecagnano (southern Italy)

OBJECTIVE

This study presents a new case of solitary osteochondroma (SOC) identified on the proximal tibia of a 4th-century BCE individual from Pontecagnano (Salerno, Italy) with an aim to contribute to differential diagnosis of bone tumors in archeological contexts.

MATERIALS

Paleopathological assessment of a male individual with an estimated age-at death of 45.9-62.9 years brought to light during the archaeological excavations in the funerary sector of 'Sica de Concillis' within the necropolis of Pontecagnano.

METHODS

Macroscopic and radiographic analyses were performed for diagnostic purposes.

RESULTS

The proximal portion of the right tibia exhibited a large exophytic bone formation extending from the anteromedial to the posteromedial portion of the diaphysis. The x-ray confirmed the lesion being characterized by regular trabecular bone tissue with cortico-medullary continuity.

CONCLUSIONS

The lesion observed is diagnostic of sessile SOC, a neoplasm that must have had aesthetic and, possibly, neurovascular complications due to its large size.

SIGNIFICANCE

By offering a detailed description of a case of tibial osteochondroma and discussing the possible complications the individual might have experienced during life, this study highlights the role and importance of benign bone tumors in paleo-oncology.

LIMITATIONS

Histological analysis was not carried out in order to preserve the integrity of the affected tibia.

SUGGESTIONS FOR FURTHER RESEARCH

More attention should be devoted to benign tumors in paleopathology as their occurrence and manifestations in the past will lead to a better understanding of their impacts on the quality of life of affected individuals and to greater knowledge of their natural history.

The use of radiomics and machine learning for the differentiation of chondrosarcoma from enchondroma

PURPOSE

To construct and compare machine learning models for differentiating chondrosarcoma from enchondroma using radiomic features from T1 and fat suppressed Proton density (PD) magnetic resonance imaging (MRI).

METHODS

Eighty-eight patients (57 with enchondroma, 31 with chondrosarcoma) were retrospectively included. Histogram matching and N4ITK MRI bias correction filters were applied. An experienced musculoskeletal radiologist and a senior resident in radiology performed manual segmentation. Voxel sizes were resampled. Laplacian of Gaussian filter and wavelet-based features were used. One thousand eight hundred eighty-eight features were obtained for each patient, with 944 from T1 and 944 from PD images. Sixty-four unstable features were removed. Seven machine learning models were used for classification.

RESULTS

Classification with all features showed neural network was the best model for both readers' datasets with area under the curve (AUC), classification accuracy (CA), and F1 score of 0.979, 0.984; 0.920, 0.932; and 0.889, 0.903, respectively. Four features, including one common to both readers, were selected using fast correlation based filter. The best performing models with selected features were gradient boosting for Fatih Erdem's dataset and neural network for Gülen Demirpolat's dataset with AUC, CA, and F1 score of 0.990, 0.979; 0.943, 0.955; 0.921, 0.933, respectively. Neural Network was the second-best model for FE's dataset based on AUC (0.984).

CONCLUSION

Using pathology as a gold standard, this study defined and compared seven well-performing models to distinguish enchondromas from chondrosarcomas and provided radiomic feature stability and reproducibility among the readers.

Classification of Chondrosarcoma: From Characteristic to Challenging Imaging Findings

Chondrosarcomas can be classified into various forms according to the presence or absence of a precursor lesion, location, and histological subtype. The new 2020 World Health Organization (WHO) Classification of Tumors of Soft Tissue and Bone classifies chondrogenic bone tumors as benign, intermediate (locally aggressive), or malignant, and separates atypical cartilaginous tumors (ACTs) and chondrosarcoma grade 1 (CS1) as intermediate and malignant tumors. respectively. Furthermore, the classification categorizes chondrosarcomas (including ACT) into eight subtypes: central conventional (grade 1 vs. 2–3), secondary peripheral (grade 1 vs. 2–3), periosteal, dedifferentiated, mesenchymal, and clear cell chondrosarcoma. Most chondrosarcomas are the low-grade, primary central conventional type. The rarer subtypes include clear cell, mesenchymal, and dedifferentiated chondrosarcomas. Comprehensive analysis of the characteristic imaging findings can help differentiate various forms of chondrosarcomas. However, distinguishing low-grade chondrosarcomas from enchondromas or high-grade chondrosarcomas is radiologically and histopathologically challenging, even for experienced radiologists and pathologists.

The 2020 World Health Organization classification of bone tumors: what radiologists should know

Improved understanding of tumor biology through molecular alteration and genetic advances has resulted in a number of major changes in the 2020 World Health Organization's (WHO) classification of bone tumors. These changes include the reclassification of the existing tumors and the introduction of several new entities. A new chapter on undifferentiated small round cell sarcomas of bone and soft tissue was added to classify Ewing sarcoma and the family of Ewing-like sarcomas, which share similar histologies but different molecular and clinical behaviors. Knowledge of the current classification of bone tumors is essential to ensure the appropriate recognition of the inherent biological potential of individual osseous lesions for optimal treatment, follow-up, and overall outcome. This article reviews the major changes to the 2020 WHO's classification of primary bone tumors and the pertinent imaging of selected tumors to highlight these changes.

Gross total resection of spinal chondrosarcoma is associated with improved locoregional relapse-free survival and overall survival

BACKGROUND

Spinal chondrosarcomas are rare malignant osseous tumors. The low incidence of spinal chondrosarcomas and the complexity of spine anatomy have led to heterogeneous treatment strategies with varying curative and survival rates. The goal of this study is to investigate prognostic factors for locoregional recurrence-free survival (LRFS) and overall survival (OS) comparing en bloc vs. piecemeal resection for the management of spinal chondrosarcoma.

METHODS

We retrospectively identified patients who underwent curative-intent resection of primary and metastatic spinal chondrosarcoma over a 25-year period. Univariate and multivariate survival analyses were conducted with LRFS as primary endpoint and OS as secondary endpoint. LRFS and OS were modeled using the Kaplan-Meier method and assessed using Cox regression analysis.

RESULTS

For 72 patients who underwent first resection, the median follow-up time was 5.1 years (95% CI 2.2-7.0). Thirty-three patients (45.8%) had en bloc resection, and 39 (54.2%) had piecemeal resection. Of the 68 patients for whom extent of resection was known, 44 patients had gross total resection (GTR) and 24 patients had subtotal resection. In survival analyses, both LRFS and OS showed statistically significant difference based on the extent of resection (p = 0.001; p = 0.04, respectively). However, only LRFS showed statistically significant difference when assessing the type of resection (p = 0.02). In addition, higher tumor grade and more invasive disease were associated with worse LRFS and OS rates.

CONCLUSION

Although in our study en bloc and GTR were associated with improved survival, heterogenous and complex spinal presentations may limit total resection. Therefore, the surgical management should be tailored individually to ensure the best local control and maximum preservation of function.

Periosteal chondrosarcoma: an unusual juxtacortical sarcoma

Periosteal chondrosarcoma is a rare tumor. It can be difficult to diagnose radiographically and pathologically and can be confused with periosteal osteosarcoma; however, the treatment of these two lesions is quite different. Increased awareness of imaging features of this lesion, particularly those that can help differentiate it from other surface-based tumors, can help one recognize this entity. We report the case of a periosteal chondrosarcoma in a young woman, highlighting the diagnostic imaging features of this disease, and her treatment with a joint-sparing geometric resection of the distal femur, using patient-specific 3D-printed cutting guides and matched allograft reconstruction.

Extraskeletal mesenchymal chondrosarcoma of the distal thumb: A case report

INTRODUCTION AND IMPORTANCE

Chondrosarcoma is the most common primary malignant bone tumor of the hand, Mesenchymal chondrosarcoma (MCS) is a rare subtype of chondrosarcoma, extraosseous mesenchymal chondrosarcoma (EMCS) is even rarer.

CASE PRESENTATION

We presented a case of primary EMCS involving the distal thumb in a 59-year-old man. The patient had abnormally grown nails and a higher skin temperature than the contralateral finger. After admission to our hospital, we found that the tumor has the possibility of malignant transformation, but imageological examinations did not reveal invasive bone lesions and calcification. Finally, due to the patient's strong desire to preserve the thumb, a conservative surgical approach was selected to preserve the patient's finger function, and histological examination indicated MCS.

CONCLUSION

EMCS is a highly malignant tumor with strong tendency of invasion and metastasis. Imaging is sometimes difficult to diagnose, and pathology is a necessary part of distinguishing between benign and malignant tumors. Operation is the major treatment to EMCS, meanwhile, adjuvant radiotherapy and chemotherapy also be effective. The overall prognosis is poor.

Survival outcomes in laryngeal chondrosarcoma: a systematic review

Laryngeal chondrosarcomas (LCS) are rare lesions that behave as locally aggressive tumours, producing symptoms such as dysphonia, dyspnoea, dysphagia and hoarseness. Different approaches for the treatment of LCS have been described in the literature. The main purpose of this investigation was to find all cases of LCS published to date and analyse management data and survival outcomes. In December 2020, a systematic review was performed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and the Provider Enrollment, Chain, and Ownership System (PECOS) method including articles published up to this date on different aspects of LCS. The search included the terms larynx, laryngeal, chondrosarcoma. A total of 148 articles were included in this systematic review describing 381 cases of LCS. Dyspnoea was the most reported symptom followed by hoarseness and neck mass sensation. Cricoid cartilage was the most usual location. Survival rate was influenced by both surgical technique (log-rank = 11.7; p = 0.008) and the degree of tumour histologic differentiation (log-rank = 18.3; p = 0.003).

Hondrosarcoma of the chest with intraabdominal distribution (case report)

A rare clinical observation of chondrosarcoma metastasis into the abdominal cavity with a specific metastatic ascitic fluid is presented. Chondrosarcomas that occur as a result of malignant transformation of benign chondroma are quite rare. Even less often in the literature, cases of chondrosarcoma metastases are described, especially in a peritoneum with the presence of metastatic ascites. The article describes a case of metastatic ascites in a 38-year old patient with chondrosarcoma, which developed against the background of previously resected rib chords. The article describes the cytological signs of chondrosarcoma in ascitic fluid.

Chest calcifications beyond the lung parenchyma-A review

OBJECTIVE

Thoracic calcifications are frequently found in chest radiographs and CTs, occurring in a wide variety of disorders. Although most calcifications are harmless sequelae of previous disease, they provide important information to establish the diagnosis. This article reviews the different types of calcified lesions found in the chest, focusing on lesions outside the lung parenchyma. A location-based approach to the differential diagnosis is used, while providing the reader with diagnostic pearls and discussing the clinical importance of the different types of calcifications.

CONCLUSION

Chest calcifications are a common finding in routine chest imaging. Understanding the different etiologies and radiologic manifestations provide the radiologist with the necessary tools to elaborate a differential diagnosis, as well as to correctly differentiate the findings that need further work-up from the ones that can be dismissed.

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.

Malignant transformation of a phalangeal enchondroma into a recurrent grade II chondrosarcoma requiring successive transcarpal amputations: a case report

We report a case of malignant transformation of a phalangeal enchondroma into a grade II chondrosarcoma requiring two successive transcarpal amputations owing to recurrence. Soft tissue defects were repaired using single-stage reconstruction with a posterior interosseous artery flap. The 2-year follow-up assessment was satisfactory and no recurrence was observed.

Generation of the Chondroprotective Proteomes by Activating PI3K and TNFα Signaling

Simple Summary

Chondrosarcoma and inflammatory arthritis are two joint-damaging diseases. Here, we examined whether a counterintuitive approach of activating tumorigenic and inflammatory signaling may generate joint-protective proteomes in mesenchymal stem cells and chondrocytes for the treatment of chondrosarcoma and inflammatory arthritis. While activating PI3K signaling and the administration of TNFα to chondrosarcoma cells and chondrocytes promoted tumor progression and inflammatory responses, those cells paradoxically generated a chondroprotective conditioned medium. Notably, the chondroprotective conditioned medium was enriched with Hsp90ab1 that interacted with GAPDH. Extracellular GAPDH interacted with L1CAM, an oncogenic transmembrane protein, and inhibited tumorigenic behaviors, whereas intracellular GAPDH downregulated p38 in chondrocytes and exerted anti-inflammatory effects. The result supports the unconventional approach of generating chondroprotective proteomes.

Abstract

Purpose: To develop a novel treatment option for Chondrosarcoma (CS) and inflammatory arthritis, we evaluated a counterintuitive approach of activating tumorigenic and inflammatory signaling for generating joint-protective proteomes. Methods: We employed mesenchymal stem cells and chondrocytes to generate chondroprotective proteomes by activating PI3K signaling and the administration of TNFα. The efficacy of the proteomes was examined using human and mouse cell lines as well as a mouse model of CS. The regulatory mechanism was analyzed using mass spectrometry-based whole-genome proteomics. Results: While tumor progression and inflammatory responses were promoted by activating PI3K signaling and the administration of TNFα to CS cells and chondrocytes, those cells paradoxically generated a chondroprotective conditioned medium (CM). The application of CM downregulated tumorigenic genes in CS cells and TNFα and MMP13 in chondrocytes. Mechanistically, Hsp90ab1 was enriched in the chondroprotective CM, and it immunoprecipitated GAPDH. Extracellular GAPDH interacted with L1CAM and inhibited tumorigenic behaviors, whereas intracellular GAPDH downregulated p38 and exerted anti-inflammatory effects. Conclusions: We demonstrated that the unconventional approach of activating oncogenic and inflammatory signaling can generate chondroprotective proteomes. The role of Hsp90ab1 and GAPDH differed in their locations and they acted as the uncommon protectors of the joint tissue from tumor and inflammatory responses.

Surgical Strategies and Outcomes for Intracranial Chondromas: A Retrospective Study of 17 Cases and Systematic Review

Objective

To improve the diagnosis and treatment of intracranial chondromas (ICDs) by discussing the clinical manifestations and imaging characteristics of ICDs, as well as surgical methods and treatment strategies.

Methods

We retrospectively analyzed 17 patients diagnosed with ICDs who underwent microsurgery or endoscopic transsphenoidal surgery at the Tangdu Hospital of Air Force Military Medical University and the Mianyang Central Hospital from January 2010 to November 2021. Clinical manifestations, imaging examinations, surgical treatments, and prognosis of these patients were analyzed.

Results

ICDs had often been misdiagnosed as craniopharyngioma, chordoma, schwannoma, cavernous hemangioma, pituitary adenoma, and meningioma before surgery. Of the 17 cases, gross total resection (GTR) was performed in 10 cases, subtotal resection (STR) in 5, and partial resection in 2. GTR of tumor was achieved in eight cases via the endoscopic endonasal transsphenoidal approach (EETA) or the extended endoscopic endonasal transsphenoidal approach (EEETA), and the remaining patients underwent craniotomies. Clinical symptoms were assessed 1 week after surgery, 10 cases were relieved at varying degrees, and four cases had no improvement. Postoperative complications included right-limb hemiparesis, diplopia, eyelid ptosis, pulmonary infection, subcutaneous hydrops, cerebrospinal-fluid leakage (CSFL), and intracranial infection (ICI). One patient received gamma knife treatment at 3 months after surgery, two patients died due to tumor progression, and the remaining patients had no tumor recurrence.

Conclusions

ICDs lack typical imaging features and are often misdiagnosed. The EETA or EEETA helps improve the surgical outcomes and GTR rates of ICDs at different sites.

Imaging characteristics of slow-growing soft tissue chondroma of the tongue: A case report

INTRODUCTION

Extraskeletal soft tissue chondroma (STC) is a rare benign tumor. Soft-tissue chondromas rarely occur in the oral cavity. In this study, we aimed to confirm a slow-growing tongue mass using magnetic resonance imaging.

PATIENT CONCERNS

A 60-year-old woman presented with a painful, slow-growing tongue mass that had persisted for 17 years. Intraoral examination revealed a pedunculated mass covered with mucosa on the right side of her tongue.

DIAGNOSIS

CT and MRI revealed a lobulated heterogeneously enhancing mass without calcification. Compared with previous images obtained 17 years prior, the mass presented slow growth, more prominent enhancement, and lobulated contour. Histopathological examination confirmed the presence of STC.

INTERVENTIONS

Excision of the mass surrounding normal tissue was performed under general anesthesia.

OUTCOMES

During 1-year follow-up period, no recurrence was observed.

CONCLUSIONS

In this study, STC lesions were slow-growing, and changed from weakly homogeneous enhancement and clean margins to markedly heterogeneous enhancement and lobulated margins over time.

Spectrum of anatomical variants, normal findings and pathology in and around the paediatric sternum

Abnormalities of the sternum and adjacent structures are an uncommon presentation in the paediatric population and can have a variety of benign and malignant causes, including normal and developmental variants of the chest wall. Although there is overlap with adults, many sternal abnormalities are unique to the paediatric population. Following clinical examination, radiography is usually the first type of imaging used; however, it is limited and often ultrasound and cross-sectional imaging are needed for further assessment. An understanding of the normal anatomy is important; however, this can be challenging due to the varied appearances of age-related changes of the sternum. The purpose of this article is to familiarize the general paediatric radiologist with the expected anatomy and imaging findings of the developing sternum, anatomical variants and pathology of the sternum and adjacent structures encountered in this group of patients.

A cartilage-forming tumor of the mandibular angle: a case report

BACKGROUND

Mandible can be the site of benign or malignant lesions of different origins, including odontogenic and non-odontogenic lesions. Cartilage-forming tumors have been rarely reported at this site. Chondrosarcoma is a rare malignant cartilage-producing neoplasm that is extremely rare in the mandible. The rarity of cartilage-forming tumor occurrence in the mandible can make diagnosis difficult for pathologists, as they do not expect this type of tumor at this anatomical site. Here we report a case of chondrosarcoma of mandibular angle.

CASE PRESENTATION

A 70-year-old Moroccan male patient consulted a dentist for wisdom tooth pain. Wisdom tooth extraction was conducted. After 6 months, the patient reported the recurrence of pain associated with swelling in the mandibular area and paresthesia along the path of the mandibular nerve. A panoramic radiograph demonstrated a mixed radiolucent-opaque lesion involving the mandibular angle. Computed tomography showed a large osteolytic spontaneously hypointense and multilobulated lesion. A biopsy was done. Histopathological examination revealed sheets and irregular lobules of atypical cells presenting cartilaginous differentiation. Tumor cells showed severe nuclear atypia and were located within a hyaline cartilage matrix. Some foci of necrosis were noted. Osteoid deposits were not found. The patient was diagnosed with grade III chondrosarcoma and underwent a right segmental mandibulectomy with submandibular lymph node dissection. Macroscopically, the tumor was localized in the mandibular angle with extension in the mandibular body. Histopathology confirmed the previous diagnosis of grade III chondrosarcoma and did not show any lymph node metastasis.

CONCLUSIONS

Owing to many histological similarities, grade III chondrosarcoma must be distinguished from chondroblastic osteosarcoma and metastatic lesions. In addition, chondroblastic osteosarcoma of the jawbones has a worse prognosis than chondrosarcoma, making the distinction between these two malignant tumors the most important concern of the pathologist when dealing with a cartilage-forming tumor at this site. Surgery with wide excision margins remains the best therapeutic approach, while the role of radiotherapy is controversial. The management of mandibular chondrosarcoma requires a multidisciplinary approach involving maxillofacial surgeons, radiologists, pathologists, and oncologists.

Dedifferentiated chondrosarcoma of the middle finger arising from a solitary enchondroma: A case report

BACKGROUND

Dedifferentiated chondrosarcoma (DDCS) accounts for 10% of all chondrosarcomas and has the poorest outcome, with a 5-year survival rate of 7%-25%. DDCS commonly occurs in the femur and pelvis, whereas DDCS of the finger is extremely rare. Furthermore, the histological findings of preexisting solitary enchondroma samples are important and valuable for diagnosing malignant transformations.

CASE SUMMARY

We report our experience with DDCS in the proximal phalanx of the left middle finger of an 87-year-old woman. She had undergone surgery for enchondroma, with curettage and artificial bone grafting, 11 years ago, in the same location. Several years after the primary surgery, the left middle finger gradually started to enlarge, and the growth speed increased in the past year. Plain radiographs showed an expansive osteolytic lesion with calcifications and residual grafting material. Owing to the suspicion of malignancy, we performed ray amputation. Histological findings revealed an abrupt transition between the low-grade chondrosarcoma and dedifferentiated sarcoma components. The dedifferentiated components showed the features of a high-grade undifferentiated pleomorphic sarcoma. The patient was diagnosed with DDCS arising from a preexisting enchondroma. She had no local recurrence or distant metastasis and died of pneumonia 6 years and 10 months after the second surgery.

CONCLUSION

The histological findings of a precursor lesion showed a typical enchondroma, suggesting that DDCS can arise from enchondroma.

Update on the imaging features of the enchondromatosis syndromes

Ollier disease and Maffucci syndrome are the commonest enchondromatosis subtypes, arising from non-hereditary mutations in the IDH1 and IDH2 genes, presenting in childhood and being characterised by multiple enchondromas. Maffucci syndrome also includes multiple soft tissue haemangiomas. Aside from developing bony masses, osseous deformity and pathological fracture, ~ 40% of these patients develop secondary central chondrosarcoma, and there is increased risk of non-skeletal malignancies such as gliomas and mesenchymal ovarian tumours. In this review, we outline the molecular genetics, pathology and multimodality imaging features of solitary enchondroma, Ollier disease and Maffucci syndrome, along with their associated skeletal complications, in particular secondary chondrosarcoma. Given the lifelong risk of malignancy, imaging follow-up will also be explored. Metachondromatosis, a rare enchondromatosis subtype characterised by enchondromas and exostoses, will also be briefly outlined.

Sedimentation sign: a classical finding on tumorous calcinosis

The authors describe the case of a man in his 60s who presented with progressive pain and swelling of the right hip. Imaging features showed a densely calcified lesion associated with 'sedimentation sign'. Laboratory tests revealed slight hyperphosphataemia. Surgical excision of the lesion was performed. Histological examination revealed chalky material surrounded by fibrosis and giant multinucleated cells, compatible with tumorous calcinosis. Patient made a full recovery. We report a rare case of tumorous calcinosis and compare this condition with its common mimics.

A Cystic Clival Chordoma with CT and MRI Unconventional Appearances

We present the first case of clival cystic chordoma with extradural location, transdural transgression, and moderate bone involvement in a 10-year-old girl. Chordoma showed unconventional appearances on computed tomography (CT) and magnetic resonance imaging (MRI), due to cystic components, extradural space location with extensive intradural extension, moderate superficial bone involvement. Surgery confirmed the extradural location and histopathological examination revealed cystic chordoma. MRI and CT findings were not characteristic for a single lesion; differential diagnoses included cystic lesions such as epidermoid and dermoid cyst, ecchordosis physaliphora, and benign notochordal cell tumors.

[Fusion-related round and spindle cell sarcomas of the bone (beyond Ewing)]

Round cell sarcomas represent a diagnostic challenge for pathologists due to the poorly differentiated pattern of these high-grade tumors. Their diagnosis often requires large immunohistochemical panels and the use of molecular pathology. These tumors are largely dominated by Ewing sarcomas, but new families are now well characterized, including in decreasing frequency order in bone, BCOR-altered sarcomas, NFATc2-rearranged sarcomas, mesenchymal chondrosarcomas and more rarely CIC-rearranged sarcomas and myoepithelial tumors. This progress report presents microscopic, immunohistochemical and molecular features of these tumors previously named by the inappropriate term "Ewing-like" sarcomas, in order to enable any pathologist to perceive the morphological features of these sarcomas, to select the immunohistochemical panel that will lead to the diagnosis and to better guide the molecular approach needed to establish the final diagnosis.

Can 18F-FDG PET/CT alone or combined with radiology be used to reliably grade cartilage bone neoplasms for surgical decision making?

OBJECTIVE

Treatment of chondrosarcomas is grade based; intralesional curettage for grade 1 and resection for grade 2 or more. Currently used methods to determine grades before surgery are not highly accurate and create a dilemma for the surgeon. We have used a PET-CT combined with imaging to answer the following study questions: (1) Does SUVmax value from an 18F-FDG PET/CT correlate with the grade of chondrosarcoma? (2) Can a cutoff SUVmax value be used to differentiate between various grades of chondroid neoplasms with sufficient sensitivity and specificity? (3) Does SUVmax guide the clinician and add value to radiology in offering histologic grade-dependent management?

METHODS

SUVmax values of patients with suspected chondrosarcoma were retrospectively correlated with the final histology grade for the operated patients. Radiologic parameters and radiology aggressiveness scores (RAS) were reevaluated and tabulated.

RESULTS

Totally 104 patients with chondroid tumors underwent 18F-FDG PET/CT assessment. In total 73 had tissue diagnosis available as a pretreatment investigation. Spearman correlation indicated that there was a significant positive association between SUVmax and the final histology grading of chondroid tumors (correlation coefficient = 0.743; P < 0.01). SUVmax cutoff of 13.3 was 88.9% sensitive and 100% specific for diagnosing dedifferentiated chondrosarcomas. An RAS cutoff value of 3 or more could diagnose IHGCS with a sensitivity of 80.7% and specificity of 93.75%. Adding an SUVmax cutoff of 3.6 improves the sensitivity to 89.5%.

CONCLUSION

SUVmax value can reliably help diagnose dedifferentiated chondrosarcoma and when added to the radiology score can improve the accuracy of grading chondrosarcoma.

Aggressive Mesenchymal chondrosarcoma of the maxilla: Case report

Introduction

Chondrosarcomas of the head and neck are extremely rare, accounting for approximatively 0.1% of all head and neck malignant tumors. Mesenchymal chondrosarcomas are particularly aggressive, with a high propensity for recurrence.

Case report

We report the case of a 25 years old man with no prior medical history, who presented to our facility with an aggressive tumor of the left maxilla. Upon radiologic and histopathological examinations, the tumor was revealed to be a mesenchymal chondrosarcoma. The patient was treated using surgical excision of the tumor, neoadjuvant chemotherapy and adjuvant radiotherapy.

Conclusion

Due to the high risk of recurrence and the possibility of metastasis occurring long after the initial diagnosis, it is important that patients with mesenchymal chondrosarcomas receive close and regular follow-ups after treatment.

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Maxillary chondrosarcoma generally presents as a painless tissue mass in the nasal cavities.

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In our case, the patient presented with many symptoms on his first consultation due to the advanced stage of tumor extension which has invaded the ipsilateral nasal cavity, the nasopharynx, oropharynx the hard palate and which arrives at the orbit without invading it.

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This case underlines the interest of multidisciplinary consultation because thanks to the decision of a first chemotherapy, the patient could then benefit from a carcinological surgery.

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The interest of a regular long-term follow-up given the high risk of recurrence.