{Reference Type}: Case Reports {Title}: A Rare Case of Lower Limb Sarcoma With BCOR-CCNB3 Mutation: Diagnosis and Treatment. {Author}: Kedia A;Singh G;Parmar S;Varsha H;Tango T;Agarwal P;Sahu S;Chauhan DR; {Journal}: Cureus {Volume}: 15 {Issue}: 2 {Year}: Feb 2023 暂无{DOI}: 10.7759/cureus.35389 {Abstract}: In the past, BCOR-CCNB3 sarcoma was believed to be comparable to Ewing's sarcoma; however, current research has proven that it is, in reality, a distinct type of the illness, now classified as a distinct entity under undifferentiated round cell sarcomas. This tumour most frequently affects teenagers and young adults, and it is more prevalent in men. It can form in both bone and soft tissue, and it appears most frequently in the pelvis, lower extremities, and paraspinal region. Here, we describe a case of a soft tissue tumour in the proximal posterior portion of the right thigh of a 12-year-old male that was subsequently shown to be a BCOR-CCNB3 fusion using genetic analysis.