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.

Application of magnetic resonance imaging in the diagnosis of soft tissue sarcoma / 中国医师进修杂志

Objective To evaluate the diagnostic value of magnetic resonance imaging (MRI) in the diagnosis of soft tissue sarcoma. Methods Seventy-four soft tissue tumors patients having underwent plain and enhanced MRI scans were selected. A retrospective case-control study was conducted to compare the demographic and MRI characteristics between 32 cases of soft tissue sarcoma and 42 cases of benign soft tissue tumor. The examined MRI characteristics included lesion location, morphology, size, signal uniformity, intratumoral sign, sign outside the tumor and intensity pattern, et al. The MRI characteristics were compared between 2 groups. Results The 32 patients with soft tissue sarcoma included 7 cases with lipoblastoma, 5 cases with pleomorphic undifferentiated sarcoma, 5 cases with fibrosarcoma, 5 cases with synovial sarcoma 5 cases, 4 cases with dermatofibrosarcoma protuberant, 2 cases with low-grade fibromyxoid sarcoma, 2 cases with alveolar soft part sarcoma, 1 case with leiomyosarcoma, and 1 case with histiocytic sarcoma. The 42 patients with benign soft tissue tumor included 15 cases with neurilemmoma, 9 cases with angioma, 8 cases with neurofibroma, 6 cases with lipoma, and 4 cases with angiolipoma. After controlling for the potential confounding effects of sex and age, whether there was high signal on T2WI and whether the tumor boundary was clear can help for distinguishing soft tissue sarcoma and benign tumor. The occurrence of high signal on T2WI was a risk factor for soft tissue sarcomas ( OR=25.05, 95% CI 4.04 to 155.28), and tumors whose boundaries were less clear ( OR=18.84, 95% CI 2.98 to 118.99) and unclear ( OR=26.59, 95% CI 3.79 to 186.71) were more likely to be soft tissue sarcomas compared to those with clear boundaries. Conclusions The MRI characteristics of soft tissue sarcomas can be used for accurate diagnosis of the tumors before treatment.

Tumor neuroectodérmico primitivo: relato de caso / Primitive neuroectodermal tumor: case report

JUSTIFICATIVA E OBJETIVOS: O tumor neuroectodérmico primitivo (PNET) pertence a um grupo de tumores de pequenas células redondas e, devido a sua semelhança biológica com os sarcomas de Ewing, tem sido incluído nesta família. O objetivo deste estudo foi descrever o quadro clínico, características de imagem e evolução de um caso de processo expansivo em coxa direita, com histologia consistente com sarcoma de Ewing extraesquelético. RELATO DO CASO: Paciente do sexo feminino, 21 anos, branca, apresentava queixa de dificuldade para deambular e dor na perna direita há aproximadamente seis meses. Ao exame físico foi detectada massa sólida na raiz da coxa direita. Exames de imagens identificaram formação expansiva sólida, sendo o estudo histopatológico/imuno-histoquímico compatível com PNET/sarcoma de Ewing extraesquelético. Foi instituído tratamento quimioterápico, que nãofoi suspenso mesmo após diagnóstico de gestação. A gravidez evoluiu com oligodramnia e óbito fetal. Dois meses após o diagnóstico, a paciente apresentou depressão, piora do estado geral e óbito. CONCLUSÃO: O estudo relatado reflete a agressividade desta doença apesar da possibilidade de multimodalidade terapêutica. A aplicação da genética molecular em estudos recentes correlaciona o rearranjo genético da translocação entre os cromossomas 11e 22 com o prognóstico.

BACKGROUND AND OBJECTIVES: Primitive neuroectodermal tumor (PNET) belongs to a family of small round cell tumors, and because of their biological similarity has been includedin the family of Ewing's sarcomas. The objective of this case was to describe the clinical, imaging characteristics and outcome of a case of an expansive process in the right thigh, with histology consistent with extraskeletal Ewing's sarcoma. CASE REPORT: Female patient, 21 years, white, featured a complaint of difficulty in walking and pain in his right leg for about six months. On examination a solid mass was detected at the root of the right thigh. Imaging techniques identified an expansive solid mass and histopathology was compatible with PNET/extra-skeletal Ewing's sarcoma. Chemotherapy was instituted, which was not suspended even after pregnancy diagnosis. It progressed with oligohydramnios and fetal death. In two months, the patient had depression, poor general condition and death. CONCLUSION: The study reported reflects the aggressive nessof this disease despite multimodality therapy. The application of molecular genetics in recent studies correlating the genetic rearrangement of the translocation between chromosomes 11:22 prognosis.