AUTHOR=Valeri Marina , Dore Leocadia , Rudini Noemi , Cieri Miriam , Elefante Grazia Maria , Saita Alberto , Bertuzzi Alexia , Colombo Piergiuseppe TITLE=Case report: Primary Ewing sarcoma of the ureter, an exceptional finding of unique manifestation of disease JOURNAL=Frontiers in Oncology VOLUME=12 YEAR=2023 URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2022.1070838 DOI=10.3389/fonc.2022.1070838 ISSN=2234-943X ABSTRACT=

Ewing sarcoma (ES) is the second most common malignant bone tumor in children and has also been described in adults with highly aggressive behavior. ES belongs to the small round blue cell tumor family and presents the distinctive translocation of FET-ETS family genes (85% with EWSR1), generating gene fusions. Extraskeletal ES mainly occurs in soft tissues; the urogenital tract is rarely affected, and ureteral localization is an exceptional event with only 4 cases described in the literature. Here we report the first Italian case of primary ES of the ureter, a 24-year-old young man with lower back pain and a narrowed left ureteral lumen on CT scan. ES of the urogenital tract is an almost unique condition with a nonspecific clinical presentation and a challenging diagnosis for pathologists. We encourage awareness of these exceptional events in the differential diagnosis of ureteral lesions in young patients.