Among 22 shared genes, SFRP4, NOX4, HOXA11, NKX2-5, CDH16 and LOC100505875 were up-regulated in primary cancer and PM cancer, and LIPF, NKX6-2, MIXL1, CWH43, SULT1E1, CXCL5, REG1A, GHRL, NKX2-2, HTR1E, HPGD, ESRRG, CYP2C19, ADH1C, PNLIPRP3 and CEACAM5 were down-regulated in both sites. The gene discussed is CEACAM5; the disease is cancer.