CEACAM5 and rheumatoid arthritis: The pooled effect size demonstrated that CEA (MD = 1.66; 95% CI: 0.28-3.03; P = 0.02) and CA19-9 (MD = 21.92; 95% CI: 10.60-33.24; P < 0.001) levels were significantly higher in the RA-ILD group compared to the RA group, with high heterogeneity observed (CEA: I2 = 94.22%, P < 0.001; CA19-9: I2 = 94.74%, P < 0.001).