The results showed that preoperative RMRP levels (ΔCt) were negatively correlated with tumor diameter (P = 0.031), stage (P = 0.038), invasion (P = 0.017) and tissue CEA expression (P = 0.032; Supplementary Table 2), whereas the individual relative changes (ΔΔCt) of plasma RMRP after surgery had a significant and negative association with lymphatic metastasis (P = 0.040) and tissue CEA expression (P = 0.049; Supplementary Table 3). Here, CEACAM5 is linked to neoplasm.