Ewing and Ewing‐like sarcomas: A morphological guide through genetically‐defined entities

Yoshida, Akihiko

doi:10.1111/pin.13293

Cited by 21 publications

(9 citation statements)

References 93 publications

(277 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This emphasizes the significance of immunohistochemistry, particularly WT1 staining, incorrect diagnosis and differentiation of renal neoplasms. On the other hand, Ewing sarcoma has a homogeneous population of tiny round cells, robust nuclear expression of NKX2.2, and diffuse membrane expression of CD99, which is compatible with the diagnostic value of these markers, as described in earlier research [ 24 , 25 ]. The anatomic distribution of Ewing sarcoma in multiple places adds to the body of knowledge, underlining the necessity of these indicators in proper identification [ 26 ].…”

Section: Discussionsupporting

confidence: 85%

Expression of NKX2.2 in Non-Ewing Tumors With Round Cell Morphology

Saeed,

Hassan,

Hussain

et al. 2023

Cureus

View full text Add to dashboard Cite

Background Round cell sarcomas pose diagnostic challenges due to overlapping histopathological features, necessitating precise immunohistochemical markers for accurate categorization. NKX2.2 has emerged as a sensitive diagnostic tool, particularly in Ewing sarcoma. This study extends this understanding to various round-cell sarcomas, shedding light on the potential diagnostic utility of NKX2.2 beyond its established role. The nuanced exploration of NKX2.2 expression aims to enhance diagnostic strategies, prognostic assessments, and therapeutic developments in the landscape of sarcoma research. Methodology Cases were retrieved from the surgical pathology and consultation files of Shaukat Khanum Memorial Cancer Hospital and Research Center, Lahore, Pakistan. Representative hematoxylin and eosin-stained slides of six different types of already confirmed tumors, including lymphoblastic lymphoma, neuroblastoma, rhabdomyosarcoma, synovial sarcoma, Wilms tumor, and Ewing sarcoma, were reviewed by a panel of pathologists. Immunohistochemistry, utilizing a rabbit anti-NKX2.2 monoclonal antibody, was performed on formalin-fixed paraffin-embedded tissue sections. The presence of NKX2.2 was defined as moderate or high nuclear immunoreactivity in at least 5% of cells. Results The histopathological examination revealed characteristic features in each sarcoma subtype, aligning with established diagnostic criteria. In Lymphoblastic lymphoma, T-cell lineage was confirmed through TdT expression, while the atypical finding of focal NKX 2.2 expression hinted at genetic diversity. Neuroblastoma exhibited the expected salt and pepper chromatin pattern, with NKX 2.2 expression raising questions about its prognostic significance. Rhabdomyosarcoma presented primitive cells expressing desmin, and NKX 2.2 focal expression echoed previous subtype-associated studies. Synovial sarcoma displayed both monophasic and biphasic growth patterns and TLE1 expression, with NKX 2.2 variation suggesting tumor heterogeneity. In Wilms tumor, the characteristic WT1 expression was observed, while NKX2.2's absence reaffirmed its irrelevance in this context. Ewing sarcoma displayed the anticipated homogenous cell population, strong NKX2.2 expression, and CD99 positivity across various sites. Furthermore, age and gender impact on this range of sarcomas found no significant relation with an expression of NKX2.2. Conclusion In conclusion, the diverse expression profiles of diagnostic markers discovered in this study, particularly the atypical expression of NKX2.2 beyond its established role in Ewing sarcoma, signify a significant advancement. This unique finding accentuates the potential diagnostic importance of NKX2.2 in various sarcomas, presenting a novel dimension to our understanding of these malignancies.

show abstract

Section: Discussionsupporting

confidence: 85%

Expression of NKX2.2 in Non-Ewing Tumors With Round Cell Morphology

Saeed,

Hassan,

Hussain

et al. 2023

Cureus

View full text Add to dashboard Cite

show abstract

“…glands or keratinisation), and site‐specific immunohistochemical markers such as TTF1 should aid in assessment. EWSR1::NFATC2 sarcomas often demonstrate a corded or reticular growth pattern within fibromyxoid background and could be focally positive for keratin; however, they are often positive for PAX7, NKX2.2, and/or NKX3.1, 36 which is lacking in EMC.…”

Section: Discussionmentioning

confidence: 99%

Keratin‐positive fibrotic extraskeletal myxoid chondrosarcoma: a close mimic of myoepithelial tumour

Sugino

Iwata²,

Satomi

et al. 2023

Histopathology

Self Cite

View full text Add to dashboard Cite

Aims: Extraskeletal myxoid chondrosarcoma (EMC) is a rare form of adult sarcoma with distinct histology and NR4A3 gene fusion. Immunohistochemically, EMCs are variably positive for S100 protein and neuroendocrine markers. Unlike histologically similar soft-tissue myoepithelial tumours, keratin expression is rare. Prompted by two recent EMC cases with diffuse keratin expression, we investigated the expression of epithelial markers in a molecularly confirmed cohort of EMC and identified two additional similar cases. Methods and results: Four keratin-positive EMCs occurred in one man and three women aged 46-59 years. All tumours displayed nonclassic histology with prominent stromal fibrosis, and keratin AE1/ AE3 was expressed either diffusely (N = 2) or focally (N = 2). In one tumour, keratin expression was limited to the sclerotic area. All tumours coexpressed epithelial membrane antigen and two additionally expressed S100 protein or glial fibrillary acidic protein. All tumours harboured NR4A3 fusions, including TAF15::NR4A3 (N = 1) and EWSR1::NR4A3 (N = 3). Two cases were initially considered as most consistent with myoepithelial tumours based on widespread stromal fibrosis and keratin expression. DNA methylation analysis classified two tumours tested as EMCs.Conclusions: We identified a small subset of EMCs characterised by keratin expression and prominent stromal fibrosis. This histological pattern must be recognised in the differential diagnosis of myoepithelial tumours because misclassification may lead to the erroneous prediction of tumour behaviour and may alter patient management. NR4A3 genetic analysis should be considered even in the face of keratin expression and prominent stromal fibrosis.

show abstract

“…However, it is likely that the last group does not represent a single entity because it includes tumors with a variety of fusions and phenotypes. 25 Managing the disease should start with neoadjuvant chemotherapy which represents the standard of care. Then comes a definitive radiation or surgery.…”

Section: Discussionmentioning

confidence: 99%

Extra-skeletal Ewing’s sarcoma of the leg with multiple skeletal and pulmonary metastases: A rare pediatric case report

El Harras,

Choayb,

Laasri

et al. 2023

SAGE Open Medical Case Reports

View full text Add to dashboard Cite

Being the second most common malignant bone tumor in children and young adults, Ewing’s sarcoma can also occur as a primary soft-tissue tumor called extraosseous or extra-skeletal Ewing’s sarcoma. It is a rare entity, especially in the pediatric population. We report the case of an adolescent who presented to our department for lower extremity magnetic resonance imaging to explore leg swelling. It revealed an extra-skeletal Ewing’s sarcoma with multiple bone metastases. By reporting this case, we also review the literature on this rare abnormality.

show abstract

Ewing and Ewing‐like sarcomas: A morphological guide through genetically‐defined entities

Cited by 21 publications

References 93 publications

Expression of NKX2.2 in Non-Ewing Tumors With Round Cell Morphology

Expression of NKX2.2 in Non-Ewing Tumors With Round Cell Morphology

Keratin‐positive fibrotic extraskeletal myxoid chondrosarcoma: a close mimic of myoepithelial tumour

Extra-skeletal Ewing’s sarcoma of the leg with multiple skeletal and pulmonary metastases: A rare pediatric case report

Contact Info

Product

Resources

About