Clinicopathological Analysis of a European Cohort of MYOD1 Mutant Rhabdomyosarcomas in Children and Young Adults.

Background: Patients with PAX3/7-FOXO1 fusion-negative rhabdomyosarcomas (fnRMS) harbouring the rare L122R MYOD1 mutation have significantly poorer prognosis than other fnRMS. We undertook a detailed clinicopathological evaluation of a cohort of patients with MYOD1 mutated fnRMS in order to improve risk stratification and treatment options.

Procedure: Histological, mutational and clinical data from a cohort of patients with MYOD1 mutant RMS treated in Europe were analysed.

Clinical recommendations for treatment of localized angiosarcoma: A consensus paper by the Italian Sarcoma Group.

Angiosarcoma (AS) represents a rare and aggressive vascular sarcoma, posing distinct challenges in clinical management compared to other sarcomas. While the current European Society of Medical Oncology (ESMO) clinical practice guidelines for sarcoma treatment are applicable to AS, its unique aggressiveness and diverse tumor presentations necessitate dedicated and detailed clinical recommendations, which are currently lacking. Notably, considerations regarding surgical extent, radiation therapy (RT), and neoadjuvant/adjuvant chemotherapy vary significantly in localized disease, depending on each different site of onset.

An algorithmic approach to the management of peripheral nerve tumours.

This article reviews the pathology and management of peripheral nerve tumours, including a framework for investigation and decision-making. Most tumours are benign, including schwannomas and neurofibromas, but malignant peripheral nerve sheath tumours can occur. The risk of malignant change is remote for schwannomas but higher for neurofibromas, particularly in neurofibromatosis type 1.

Diagnostic and prognostic role of synovial tissue analysis in juvenile idiopathic arthritis: a monocentric study.

Objectives: This study investigates the diagnostic role of synovial tissue analysis in children presenting with arthritis and assesses its prognostic significance to predict clinical outcome in juvenile idiopathic arthritis (JIA).

Methods: Synovial samples of paediatric patients undergoing synovial biopsy between 1995 and 2020 were analysed histologically and immunohistochemically. Relationships between histological/immunohistochemical parameters and clinical variables were assessed.

Bizarre parosteal osteochondromatous proliferation: an educational review.

Bizarre parosteal osteochondromatous proliferation (BPOP) is a surface-based bone lesion belonging to the group of benign chondrogenic tumors. The aim of this review is to familiarize the readers with imaging features and differential diagnosis of BPOP, also addressing pathological presentation and treatment options. The peak of incidence of BPOP is in the third and fourth decades of life, although it can occur at any age.

MRI radiomics-based machine learning for classification of deep-seated lipoma and atypical lipomatous tumor of the extremities.

Purpose: To determine diagnostic performance of MRI radiomics-based machine learning for classification of deep-seated lipoma and atypical lipomatous tumor (ALT) of the extremities.

Material And Methods: This retrospective study was performed at three tertiary sarcoma centers and included 150 patients with surgically treated and histology-proven lesions. The training-validation cohort consisted of 114 patients from centers 1 and 2 (n = 64 lipoma, n = 50 ALT).

3D vs. 2D MRI radiomics in skeletal Ewing sarcoma: Feature reproducibility and preliminary machine learning analysis on neoadjuvant chemotherapy response prediction.

Objective: The extent of response to neoadjuvant chemotherapy predicts survival in Ewing sarcoma. This study focuses on MRI radiomics of skeletal Ewing sarcoma and aims to investigate feature reproducibility and machine learning prediction of response to neoadjuvant chemotherapy.

Materials And Methods: This retrospective study included thirty patients with biopsy-proven skeletal Ewing sarcoma, who were treated with neoadjuvant chemotherapy before surgery at two tertiary sarcoma centres.

Significant association between FGFR1 mutation frequency and age in central giant cell granuloma.

Central giant cell granulomas (CGCG) are rare intraosseous osteolytic lesions of uncertain aetiology. Despite the benign nature of this neoplasia, the lesions can rapidly grow and become large, painful, invasive, and destructive. The identification of molecular drivers could help in the selection of targeted therapies for specific cases.

Secondary osteosarcoma: a challenge indeed.

Background: The risk of survivors developing a secondary bone sarcoma after being treated for pediatric cancers is well established. The aim of this study was to examine the clinical characteristics and outcomes of patients with secondary osteosarcoma (SOS).

Methods: The study concerns survivors of childhood and adolescence primary neoplasms (PN) treated with chemotherapy, with or without radiotherapy and surgery, subsequently diagnosed with SOS.

Rechallenge of denosumab in advanced giant cell tumor of the bone after atypical femur fracture: A case report and review of literature.

Giant cell tumor of the bone (GCTB) is a locally aggressive neoplasm where surgery is often curative. However, it can rarely give rise to distant metastases. Currently, the only available active therapeutic option for unresectable GCTB is denosumab, an anti-RANKL monoclonal antibody that dampens the aggressive osteolysis typically seen in this disease.

Diffusion-weighted MRI radiomics of spine bone tumors: feature stability and machine learning-based classification performance.

Purpose: To evaluate stability and machine learning-based classification performance of radiomic features of spine bone tumors using diffusion- and T2-weighted magnetic resonance imaging (MRI).

Material And Methods: This retrospective study included 101 patients with histology-proven spine bone tumor (22 benign; 38 primary malignant; 41 metastatic). All tumor volumes were manually segmented on morphologic T2-weighted sequences.

MRI radiomics-based machine learning classification of atypical cartilaginous tumour and grade II chondrosarcoma of long bones.

Background: Atypical cartilaginous tumour (ACT) and grade II chondrosarcoma (CS2) of long bones are respectively managed with watchful waiting or curettage and wide resection. Preoperatively, imaging diagnosis can be challenging due to interobserver variability and biopsy suffers from sample errors. The aim of this study is to determine diagnostic performance of MRI radiomics-based machine learning in differentiating ACT from CS2 of long bones.

Management of intrathoracic phosphaturic mesenchymal tumor by nonintubated uniportal video-assisted thoracic surgery in a fragile patient.

Background: Phosphaturic mesenchymal tumors are rare neoplasms, frequently presenting with osteomalacia. These neoplasms usually grow at a slow rate and are associated with unspecific symptoms.

Case: In this study, we present the case of a 70-year-old woman who had been suffering from musculoskeletal pain, hypophosphatemia, and spontaneous fractures.

Ki-67 immunoexpression and radiological assessment of necrosis improves accuracy of conventional and modified core biopsy systems in predicting the final grade assigned to adult-soft tissue sarcomas. An international collaborative study.

Based on the French Federation Nationale des Centers de Lutte Contre le Cancer (FNCLCC) grading system, this study assesses the accuracy of conventional and modified core biopsy (CB) systems in predicting the final grade (low vs high) assigned to the resected specimen. Substituting Ki-67 immunoexpression for mitotic count, and radiological for histological assessment of necrosis, we used two modified FNCLCC CB grading systems: (1) Ki-67 immunoexpression alone, and (2) Ki-67 plus radiological assessment of necrosis. We graded 199 soft tissue sarcomas (STS) from nine centers, and compared the results for the conventional (obtained from local histopathology reports) and modified CB systems with the final FNCLCC grading of the corresponding resected specimens.

CT radiomics-based machine learning classification of atypical cartilaginous tumours and appendicular chondrosarcomas.

Background: Clinical management ranges from surveillance or curettage to wide resection for atypical to higher-grade cartilaginous tumours, respectively. Our aim was to investigate the performance of computed tomography (CT) radiomics-based machine learning for classification of atypical cartilaginous tumours and higher-grade chondrosarcomas of long bones.

Methods: One-hundred-twenty patients with histology-proven lesions were retrospectively included.

Radiomic Machine Learning Classifiers in Spine Bone Tumors: A Multi-Software, Multi-Scanner Study.

Purpose: Spinal lesion differential diagnosis remains challenging even in MRI. Radiomics and machine learning (ML) have proven useful even in absence of a standardized data mining pipeline. We aimed to assess ML diagnostic performance in spinal lesion differential diagnosis, employing radiomic data extracted by different software.

MAP2K1-driven mixed Langerhans cell histiocytosis, Rosai-Dorfman-Destombes disease and Erdheim-Chester disease, clonally related to acute myeloid leukemia.

Mixed histiocytoses are a rare and recently recognized subset of histiocytic disorders that may involve the skin, characterized by the synchronous or metachronous development of lesions with Langerhans and/or non-Langerhans cell histiocytosis histopathological features. Around 10% of patients diagnosed with histiocytosis may develop a hematological malignancy, often with dramatic prognostic consequences. We hereby describe the exceptional case of a patient developing a MAP2K1-driven mixed histiocytosis with Langerhans cell histiocytosis, Rosai-Dorfman-Destombes disease, and Erdheim-Chester disease features and cutaneous involvement, progressing to a fatal and clonally-related acute myeloid leukemia.

Vertebroplasty shows no antitumoral effect on vertebral metastasis: a case-based study on anatomopathological examinations.

Purpose: Percutaneous vertebroplasty (VTP) is a well-known surgical technique used for pain management and vertebral consolidation in the treatment of osteolytic metastases of the spine. While this indication is proven and commonly accepted, an antitumoral effect of polymethylmethacrylate (PMMA) has been proposed but not yet demonstrated. The aim of our study is to evaluate the evidences of antitumoral effect on anatomopathological examination.

Expression profiling of microRNAs and isomiRs in conventional central chondrosarcoma.

Conventional central chondrosarcoma (CCC) is a malignant bone tumor that is characterized by the production of chondroid tissue. Since radiation therapy and chemotherapy have limited effects on CCC, treatment of most patients depends on surgical resection. This study aimed to identify the expression profiles of microRNAs (miRNAs) and isomiRs in CCC tissues to highlight their possible participation to the regulation of pathways critical for the formation and growth of this type of tumor.

When primary hyperparathyroidism comes as good news.

Summary: Brown tumors are osteoclastic, benign lesions characterized by fibrotic stroma, intense vascularization and multinucleated giant cells. They are the terminal expression of the bone remodelling process occurring in advanced hyperparathyroidism. Nowadays, due to earlier diagnosis, primary hyperparathyroidism keeps few of the classical manifestations and brown tumors are definitely unexpected.

MRI radiomics-based machine-learning classification of bone chondrosarcoma.

Purpose: To evaluate the diagnostic performance of machine learning for discrimination between low-grade and high-grade cartilaginous bone tumors based on radiomic parameters extracted from unenhanced magnetic resonance imaging (MRI).

Methods: We retrospectively enrolled 58 patients with histologically-proven low-grade/atypical cartilaginous tumor of the appendicular skeleton (n = 26) or higher-grade chondrosarcoma (n = 32, including 16 appendicular and 16 axial lesions). They were randomly divided into training (n = 42) and test (n = 16) groups for model tuning and testing, respectively.

ZNF687 Mutations in an Extended Cohort of Neoplastic Transformations in Paget's Disease of Bone: Implications for Clinical Pathology.

Neoplastic transformation is a rare but serious complication of Paget's disease of bone (PDB), occurring in fewer than 1% of individuals with polyostotic disease. Their prognosis is poor, with less than 50% surviving 5 years. In 2016, the genetic alteration of giant cell tumor (GCT) complicating PDB was identified as a founder germline mutation (P937R) in the ZNF687 gene.

NKX3-1 Is a Useful Immunohistochemical Marker of EWSR1-NFATC2 Sarcoma and Mesenchymal Chondrosarcoma.

NK3 homeobox 1 (NKX3-1) is widely accepted as a highly sensitive and specific marker for prostatic adenocarcinoma. Prompted by published transcriptome data showing upregulation of NKX3-1 mRNA expression in EWSR1-NFATC2 sarcoma, we explored the utility of NKX3-1 immunohistochemistry in sarcoma diagnosis. We applied NKX3-1 immunohistochemistry to 11 EWSR1-NFATC2 sarcomas and 168 mimics using whole tissue sections.

Patient-derived organoids as a potential model to predict response to PD-1/PD-L1 checkpoint inhibitors.

Selection of cancer patients for treatment with immune checkpoint inhibitors remains a challenge due to tumour heterogeneity and variable biomarker detection. PD-L1 expression in 24 surgical chordoma specimen was determined immunohistochemically with antibodies 28-8 and E1L3N. The ability of patient-derived organoids to detect treatment effects of nivolumab was explored by quantitative and qualitative immunofluorescence and FACS analysis.