From the current researches on gastric cancer, it is known that a variety of prognostic factors can affect the survival rate of gastric cancer patients: age, tumor stage, tumor size, radiotherapy, chemotherapy, surgical resection, venous invasion, Helicobacter pylori eradication, preoperative systemic immune inflammation index, tumor deposits and some miRNA (miR-23b, ETS1, and TCF4) [13–18], among these factors, the prognostic value of tumor size is often overlooked, and furthermore, consensus on the optimal cut-off point for tumor size is difficult. The gene discussed is ETS1; the disease is gastric cancer.