Fig. 2

Correlation between tumor size and NLR (a), PLR (b), OPNI (c), and Ki-67 index (d). The correlation of continuous variables was calculated by Pearson correlation coefficient, while discrete variables by Spearman’s correlation coefficient. Higher OPNI was associated with primary tumor site of stomach (P < 0.01), smaller tumor size (P < 0.017), lower mitotic index (P < 0.001), lower modified NIH risk classification (P < 0.001), less gastrointestinal bleeding rate (P < 0.01) and tumor rupture (P < 0.01), and much lower tumor relapse rate (P < 0.01)