Adverse prognostic impact of the loss of STAG2 protein expression in patients with newly diagnosed localised Ewing sarcoma: A report from the Children’s Oncology Group

Shulman DS, Chen S, Hall D, Nag A, Thorner AR, Lessnick SL, Stegmaier K, Janeway KA, DuBois SG, Krailo MD, Barkauskas DA, Church AJ, Crompton BD. Adverse prognostic impact of the loss of STAG2 protein expression in patients with newly diagnosed localised Ewing sarcoma: A report from the Children’s Oncology Group. Br J Cancer. 2022 Dec;127(12):2220-2226. doi: 10.1038/s41416-022-01977-2. Epub 2022 Oct 11. PubMed PMID: 36221002; PubMed Central PMCID: PMC9726932.

Ewing sarcoma (EWS) is an aggressive sarcoma with no validated molecular biomarkers. We aimed to determine the frequency of STAG2 protein loss by immunohistochemistry (IHC) and whether loss of expression is associated with outcome. We performed a retrospective cohort study of patients with EWS enrolled to Children’s Oncology Group studies. We obtained unstained slides from 235 patients and DNA for sequencing from 75 patients. STAG2 expression was tested for association with clinical features and survival was estimated using Kaplan–Meier methods with log-rank tests.