The prediction of survival of patients with gastric cancer with PD-L1 expression using contrast-enhanced ultrasonography.

Gastric cancer is the one of the most common cancers around the world. The prognosis of gastric cancer remains poor, due to the biological characteristics of the primary tumor as well as the recurrence after treatment. Accumulating evidence suggests the implication of programmed death ligand-1 (PD-L1) in the pathogenesis and prognosis of cancer. This study aimed to explore the CEUS as a valuable tool to improve the assessment of the therapeutic effect of the PD-L1 blocker in the treatment of gastric cancer. A total number of 105 patients with gastric cancer were enrolled in this study from June 2008 to December 2011 in our hospital. The association of PD-L1 expression level (105 cases) and CEUS parameters (100 cases) with the prognosis of gastric cancer was examined. The results showed that PD-L1-positive staining was associated with the depth of invasion, differentiation, and poor prognosis of patients with gastric cancer. The CEUS intensity (positive) exhibited poor prognosis compared to the negative counterpart. Moreover, PD-L1 and CEUS co-positivity was significantly related to a poor prognosis. The characteristic of ultrasonography images correlated with the expression of PD-L1 (r = 0.46, P = 0.0003). Collectively, the mean intensity of contrast-enhanced ultrasonography is a useful predictor in the PD-L1 expression in gastric cancer. The ultrasonography and CEUS parameter could be considered as the predictor of response to PD-L1 blocker treatment in the clinical practice.