The Correlation Of Tumor Immune Microenvironment In Pancreatic Cancer Between Clinicopathologic And Prognostic Outcomes

PurposePancreatic carcinoma is a common gastrointestinal cancer, but the prognosis of pancreatic carcinoma remains dismal.Because there are difficulties in early diagnosis and lack of effective adjuvant treatment, recurrence and metastasis after surgery also remains a major obstacle. For these reasons, immunotherapy was given expectations. Tumor-infiltrating lymphocytes (TIL) including CD8+ cytotoxic T cells (CTL), regulatory T cells (CD4+ CD25+, Tregs),et, al, play an important role in the tumor microenvironment. This aim of this study was to investigate the type, number, location of TIL by immunol histochemistry techniques and the mechanism of immune escape and factors related to the prognosis of pancreatic carcinoma cancer.MethodsWe enrolled 92 cases, which have a complete clinical and paraffin specimens of pancreatic carcinoma. We investigate the clinical significance and correlation of the prognostic factors by statistical analysis in order to screen the significant effect on prognosis factors. Using the ordinary and double immunol histochemistry staining of pancreatic carcinoma tumor tissue, adjacent and normal tissues, the CD4+ T cells, CD8 effector T cells, granzyme B+ activated cytotoxic cells (granzyme B, CTL specific of markers), Foxp3+ regulatory T cells (Tregs specific marker) and their prognosis were assessed.ResultsThe most frequent age of Pancreatic carcinoma ranged from 50-70 year-old and the head of pancreatic cancer was more common. TNM tumor stage, differentiation grade, lymph node metastasis and neural invasion are poor prognostic factors.The number of CD8+ CTL in microenvironment of pancreatic carcinoma, had significant correlation with the tumor differentiation grade, TNM stage, lymph node metastasis, neural invasion and vascular metastasis, respectively. The number of FOXP3+ Treg had significant correlation with tumor differentiation grade, TNM stage, lymph node metastasis and neural invasion, respectivelySurvival analysis showed that the number of FOXP3+ Treg detecting both in pancreatic carcinoma and tumor adjacent tissue microenvironment, had significant negative correlation with OS (Overall Survival), respectively (P=0.001, P=0.010); the number of CD8+ CTL detecting in cancer micro-environment had a significant positive correlation with OS (P=0.029), and CD8+ CTL in adjacent cancer microenvironment had no significant correlation with OS (P=0.486); the number of CD4+ Tc detecting both in pancreatic carcinoma and adjacent tumor microenvironment, had no significant correlation with OS (P=0.319, P=0.345).ConclusionsThe levels of CD4+ CD25+ Tregs and CD8+ CTL in the microenvironment of pancreatic carcinoma are significant factors for OS:CD4+ CD25+ Tregs was negatively correlated with OS, and CD8+ CTL positively.