CD274 and familial pancreatic carcinoma: However, it was significantly correlated with CA- 199 (P=0.013), TNM stage (0.023), and lymph node metastasis (P= 0.003).The density of PD-L1+ cells density that exhibit regulatory T cell immunity showed significant associations only with CA- 199 (P=0.014), CEA (P=0.032), and lymph node metastasis (P=0.009) in cases of pancreatic cancer, as shown in Table 1.