Background: Immunotherapy has shown promise against solid tumors. However, the clinical significance of programmed cell death 1(PD-1) and programmed cell death ligand 1(PD-L1) in pancreatic ductal adenocarcinoma(PDAC) remains unclear. This meta-analysis aimed to analyze the prognostic effect of PD-L1 in PDAC.Data sources: Electronic search of the Pub Med, Cochrane Library and Web of Science was performed until December 2016. Through database searches, we identified articles describing the relationship between PD-L1 status and PDAC patient prognosis. Meta-analysis was performed to investigate the relationship between PD-1 and overall survival(OS).Results: Nine studies with 989 PDAC patients were included for PD-L1 expression analysis. And 5 studies with 688 PDAC patients were included in the prognostic analysis. The PD-L1 positive rate measured by immunohistochemistry(IHC) was higher than that measured by polymerase chain reaction(PCR)(P < 0.001). PDAC patients with high expression levels of PD-L1 had significantly reduced OS(HR = 2.34;95% CI: 1.78–3.08). Subgroup analysis showed that the prognostic effect of PD-L1 levels was similar between the IHC and PCR methods. The PD-L1 positive rate was associated with PDAC T stages; the PD-L1 positive rate in the T3–4 group was higher than that in the T1-2 group(OR = 0.37; P = 0.001).Conclusions: High PD-L1 expression levels predicted a poor prognosis in PDAC patients. Thus, PD-L1 status helps determine treatment in PDAC patients.
Pancreatic fistula is one of the most common complications after the distal pancreatectomy.Many methods have been tried to solve the problem,but no one is optimal,especially for the soft pancreatic stump cases.This study used ligamentum teres hepatis as a patch to cover the pancreatic stump.Between October 2010 and December 2012,seventyseven patients who had undergone distal pancreatectomy with a soft pancreatic stump were divided into two groups:group A(n=39,patients received conventional ligated main pancreatic duct method)and group B(n=38,patients underwent a coverage procedure).Patients in group A had a longer recovery from postoperative pancreatic fistula than those in group B(16.4±3.5 vs 10.8±1.6 days,P<0.05).The coverage procedure with ligamentum teres hepatis is a safe,effective and convenient method for patients with a soft pancreas remnant during distal pancreatectomy.
