TP53 and Ewing sarcoma: We studied a cohort of patients with localised and metastatic Ewing sarcoma treated with VDC/IE to determine: (a) whether dysregulated STAG2 and p53 expression can be identified through IHC in Ewing sarcoma; (b) whether alterations in protein expression are associated with deleterious gene alterations; and (c) whether loss of STAG2 and p53 are associated with clinical features and outcomes.