CD99 (CD99 Molecule)

Comparative in vitro binding analyses demonstrated that the scFv containing the shorter 15-mer linker exhibits significantly enhanced affinity and specificity toward CD99-overexpressing Ewing sarcoma cells relative to the 18-mer variant, highlighting linker length as a critical determinant of scFv performance. These findings establish a rational design principle for optimizing CD99-targeting scFvs and support the potential application of the 15-mer scFv in CAR-T cell development and in targeting other CD99-overexpressing carcinomas.

In EFTs, EWSR1 gene rearrangement is most common, followed by FUS gene rearrangement. CD99 immunohistochemistry with additional molecular analysis is essential for further classification of EFTs. A detailed diagnostic algorithm including histology, IHC, and molecular studies is imperative for accurate subcategorization of EFTs.

Surgical resection and cervicothoracic fixation were performed, followed by radiotherapy (30 Gy/10 fractions) and Ewing-based chemotherapy (doxorubicin/ifosfamide). Local recurrence occurred despite multimodal therapy. This case highlights the clinical and diagnostic challenges associated with EWSR1-rearranged non-ETS sarcomas, which exhibit distinct molecular behaviors, morphology, and treatment responses compared to classical Ewing sarcoma.

After the operation, the patient was treated with vincristine-doxorubicin-cyclophosphamide and ifosfamide-etoposide chemotherapy, which resulted in a partial radiological response. This case illustrates the diagnostic difficulties associated with intracranial ES due to its radiological similarity to meningioma and stresses the importance of immunohistochemical and genetic analysis for a conclusive diagnosis. Early multimodal management is vital for improving survival in such rare cases.

The ESM1-ANGPTL4-FASN-trioleate axis orchestrates metabolic reprogramming and endothelial activation, representing a promising therapeutic target. Future studies should explore combination therapies targeting this axis and overcoming bevacizumab resistance in HCC.

The patient received six cycles of vincristine-doxorubicin-cyclophosphamide alternating with ifosfamide-etoposide, followed by partial amputation of the distal phalanx with clear margins. Ewing sarcoma of the great toe is exceptionally rare but can be successfully treated when identified early and managed with coordinated multimodal therapy. Clinicians should maintain vigilance for malignancy in non-healing digital lesions to ensure timely intervention and durable outcomes.

Histology showed sheets of small round cells within a sclerotic stroma, and immunohistochemistry positivity for CD99, vimentin, cyclin D1, BCL2, and NKX2.2 confirmed EWS. This case underscores the diagnostic difficulty of sinonasal small round cell tumors and the necessity of thorough histopathological and immunohistochemical analysis.

CD5, CD117 and Glut1 are diffusely expressed in MNC, but not in MNT. The genetic alterations in MNC are more diverse than those of MNT, but MNC lacks the characteristic GTF2I mutation of MNT.

Neoadjuvant chemotherapy can facilitate tumor conversion, while surgery plays a pivotal role in localized cases with incomplete chemotherapeutic response. Multidisciplinary management is essential for optimizing outcomes.

However, these features may not correlate with prognosis. This study represents the first systematic radiologic evaluation of NFATC2-rearranged bone sarcomas, highlighting distinctive characteristics that may aid pathologists in their initial diagnostic assessments.

The identification of NSE and S100 as robust prognostic biomarkers suggests that these widely available immunohistochemical stains provide valuable information beyond standard diagnostic information. These findings support the integration of automated data extraction tools in research workflows and suggest that NSE and S100 status should be considered in the design of future risk-stratified clinical trials for Ewing sarcoma.

As primary treatment is chemotherapy, accurate diagnosis on limited material such as FNAC is critical. The recognition of cytological features and follow up with appropriate ancillary testing has the potential to improve management of these patients.