Kaplan-Meier plot analyses of OS between the databases showed that GC patients with high expression of EFNA3 had a poor prognosis, which was also closely related to gender and classification, stages 3 and 4, stage T3, stages N1 and 2, classification of intestinal, whereas the prognosis of GC patients with high expression of EFNA3 in GEPIA2 was good. The gene discussed is EFNA3; the disease is gastric cancer.