CEA has been reported to have a low sensitivity of 39.5%, but acceptable specificity of 81.3% as a biomarker in PC.17 A previous study has showed that the CEA level was a reliable prognostic predictor in PDAC patients.18 Elevated levels of CEA were associated with poor prognosis for patients with PC.19, 20 However, until now, there have been no literature revealing the importance of the status of CEA level in the diagnosis of PCLM. The gene discussed is CEACAM5; the disease is pachyonychia congenita.