Work

Rare FUS::FEV–Rearranged Adamantinoma-Like Ewing Sarcoma Arising in the Submandibular Gland

Year: 2025

Type: article

Abstract: BACKGROUND: Adamantimoma-Like Ewing Sarcoma (ALES) is a rare variant of Ewing sarcoma that poses significant diagnostic challenges in the head and neck due to morphologic overlap with basaloid carcinomas and neuroendocrine neoplasms. CASE PRESENTATION: We report a case of a middle-aged man with a left submandibular gland mass showing classic histologic features of ALES, including basaloid nests with peripheral palisading, rosette formation, and high mitotic activity. RESULTS: Immunohistochemistry showed co-expression of p63/p40, CD99, and cytokeratins, with patchy synaptophysin positivity and an elevated Ki-67 proliferation index. FISH for EWSR1 was negative, but next-generation sequencing identified a rare FUS::FEV fusion, previously reported only three times in ALES and never in the submandibular gland. CONCLUSION: This case highlights the importance of extended molecular testing when EWSR1 FISH is negative; as alternate FET::ETS fusions may underlie the diagnosis.

Source: Head and Neck Pathology

DOI: 10.1007/s12105-025-01857-0

Authors: Tomilola Agboola, Daniel L. Miller

Institution: Washington University in St. Louis

Language: English

Topic: Sarcoma Diagnosis and Treatment

Subfield: Pulmonary and Respiratory Medicine

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: hybrid

Estimated APC paid: $2,690