Radiological and Pathological Diagnosis of an Incidental Askin Tumor
Askin tumor, Ewing sarcoma, EWS-FLI1, FUS-ERG
Diagnosis | Neoplasms | Radiology
A 53-year-old male with no significant past medical history presented with an acute traumatic fracture of his thumb. Preoperative chest radiograph before K-wire fixation demonstrated an incidental 9 cm opacity of the left lung. Chest computed tomography revealed a 6.3 cm aggressive appearing pleural-based mass with erosion and destruction of the underlying rib. The patient underwent percutaneous biopsy with interventional radiology, and pathology revealed a small round blue cell tumor with positive CD99 staining and a FUS-ERG chromosomal translocation. The patient was diagnosed with Askin tumor, a peripheral primitive neuroectodermal tumor of the thoracopulmonary region belonging to the Ewing sarcoma tumor family. Computed tomography and magnetic resonance imaging of Askin tumors may show features such as a heterogeneous soft tissue mass, pleural effusion, rib destruction, hemorrhage, necrosis, and cystic degeneration. Askin tumors typically exhibit the EWS-FLI1 fusion mutation, although FUS-ERG chromosomal translocation has been described. Both rarity and variability of Askin tumors present a diagnostic challenge for clinicians. Collaborative effort amongst radiologists and pathologists is essential for diagnosis.
Publisher or Conference
Radiology Case Reports
Covello B, Hartman S, Kaufman S, Enrizo O. Radiological and pathological diagnosis of an incidental Askin tumor. Radiol Case Rep. 2021;16(6):1245-1248. https://doi.org/10.1016/j.radcr.2021.02.060