Methods: In the present case–control study, we selected BTLA tagging single-nucleotide polymorphisms (SNPs) (rs16859629 T>C, rs1982809 G>A, rs2171513 G>A and rs3112270 A>G) and conducted a case–control study to identify the association of BTLA SNPs with risk of esophagogastric junction adenocarcinoma (EGJA). Here, BTLA is linked to gastroesophageal junction adenocarcinoma.