AimsCD93 was recently identified as a promising therapeutic target for angiogenesis blockade in various tumors. Herein, we aimed to investigate the expression and clinicopathological significance of CD93 in gastric adenocarcinoma.MethodsThe gene expression of CD93 gastric adenocarcinoma was assessed using The Cancer Genome Atlas (TCGA) dataset. We then analyzed CD93 expression in 404 cases of gastric adenocarcinoma using immunohistochemistry. Clinicopathological associations and prognostic implications of CD93 expression were further investigated.ResultsUsing the TCGA dataset, we observed a significantly elevated CD93 gene expression in gastric adenocarcinoma compared to normal gastric tissues. The immunohistochemistry assay revealed a highly variable CD93 expression among patients with gastric adenocarcinoma, consistently demonstrating higher intratumor expression than in adjacent normal tissues. Notably, CD93 was predominantly expressed on the membrane of CD31+ vascular endothelial cells. Furthermore, patients with higher CD93 expression demonstrated significantly poorer overall survival. Accordingly, higher CD93 expression was associated with deeper invasion and a higher possibility of lymph node metastasis and developing tumor thrombus. Cox proportional hazards regression suggested CD93 expression was an independent predictor for the prognosis of patients with gastric adenocarcinoma.ConclusionsOur study revealed a significantly higher CD93 expression in gastric adenocarcinoma when compared with adjacent normal gastric tissues, and demonstrated its predominant expression on vascular endothelial cells. Our findings also highlighted the clinicopathological significance of CD93 in gastric adenocarcinoma, shedding light on a potential therapeutic target.