Allogeneic blood transfusion (ABT) is a routine medical procedure used to increase patient hemoglobin (Hb) levels.[1] An accurate understanding of the clinical outcomes of perioperative ABT is essential in patients with extremity bone sarcomas (EBSs) because the potential need for perioperative ABTs is high due to anemia caused by preoperative chemotherapy and blood loss during extensive resections in such patients. Here, GSTM1 is linked to anemia (phenotype).