PCDH1 and metastatic malignant neoplasm in the lymph nodes: The HR values indicating lymph node metastasis, degree of neural invasion and PCDH1 expression with respect to the OS of the patients were 1.926, 2.09 and 1.647, respectively (P < 0.05) (Fig. 1F), indicating that PCDH1 expression is an independent prognostic factor for the OS of PDAC patients.