Fig. 1

a Representative microscopic images of CD4⁺, CD8⁺ and CD163⁺ cells in primary and peritoneal lesions of gastric cancer. Each cell was determined by immunohistochemically (original magnification × 400). b Comparisons of tumor immune microenvironment between primary and peritoneal lesions in gastric cancer patients. Each cell was measured and shown as average count of five non-overlapping tumor areas. There were significant differences in CD8⁺ and CD163⁺ cell count between primary and peritoneal lesions (P = 0.01, P = 0.016).