[An unusual adrenal tumor: Ewing tumor]

Area of Science:

• Oncology
• Pathology
• Genetics

Background:

• Ewing tumors typically affect bone and soft tissues, with rare instances of visceral involvement.
• Adrenal gland involvement by Ewing tumors is exceptionally uncommon, with fewer than 10 reported cases.
• Diagnosing rare tumors requires integrating morphological, immunohistochemical, and molecular findings.

Observation:

• A voluminous adrenal tumor was identified in a pregnant woman at 26 weeks gestation.
• Histopathological examination revealed sheets of monomorphous cells with high mitotic activity.
• Tumor cells expressed cytokeratins AE1/AE3, EMA, and CD99.

Findings:

• Differential diagnoses included poorly differentiated synovialosarcoma, sarcomatoid carcinoma, and Ewing tumor.
• Molecular analysis confirmed the presence of the EWS/FLI1 transcript, confirming a diagnosis of Ewing/peripheral primitive neuroectodermal tumor (pPNET).
• This case represents a rare instance of primary adrenal Ewing tumor.

Implications:

• The study underscores the utility of molecular diagnostics in confirming rare and atypical tumor diagnoses.
• The origin of Ewing tumor cells from mesenchymal stem cells may explain its occurrence in unusual sites like the adrenal gland.
• This case expands the understanding of Ewing tumor's potential locations and diagnostic challenges.