PDCD1 and metastatic malignant neoplasm in the lymph nodes: In the univariate analyses, CA19-9(P = 0.001), tumor size (P = 0.003), number (P = 0.002), lymph node metastasis (P < 0.001), TNM stage (P < 0.001), and PD-1 (P < 0.001) were found to correlate with OS.