Sarcoma with BCOR genetic alteration encompasses different subtypes, with two notable ones being sarcoma with internal tandem duplication of BCOR gene (BCOR-ITD) and BCOR-related gene fusion such as CCNB3. BCOR::CCNB3 fusion is a frequently observed genetic alteration in this category, characterized by the fusion of the BCOR and CCNB3 genes. The gene discussed is BCOR; the disease is sarcoma.