Prognostic Analysis Of Single-center Pancreatic Ductal Adenocarcinoma And Establishment Of Gene Mutation Expression Profiles And Exploration Of Potential Intervention Targets

Part I Analysis of prognostic factors of pancreaticoduodenectomy for pancreatic ductal adenocarcinoma Objective To analyze the relationship between clinicopathological data and prognosis in patients with pancreatic ductal adenocarcinoma undergoing pancreaticoduodenectomy.Methods A retrospective analysis of the clinical and pathological data of50 patients with pancreaticoduodenectomy and pathological diagnosis of pancreatic ductal adenocarcinoma in the Department of Hepatobiliary Surgery,First Affiliated Hospital of Hunan Normal University from January 2016 to December 2018.The postoperative survival was followed up and the prognostic factors were analyzed.Results Among the 50 patients,high,moderate,moderate-low,and poorly differentiated adenocarcinoma were found in 3(6.0%);22(44.4%),12(24.0%),and 13(26.0%);lymph node metastasis 16 cases(32.0%),34 cases of nerve invasion(68.0%),The median survival time was 18 months,and the 1-,2-,and 3-year survival rates were 80.9%,55.6%,and 30.8%,respectively.Univariate analysis found that preoperative biliary drainage(P=0.046),lymph node metastasis(P=0.048),postoperative radiotherapy(P=0.028)were factors for survival of patients;multi-variate analysis showed that abdominal infection(HR= 0.169)95% CI0.041-0.692 P=0.013)is an independent protective factor for the prognosis of patients with pancreatic ductal adenocarcinoma,and neurological invasion(HR=3.888 95% CI 1.000-15.109 P=0.049)is an independent risk factor for prognosis.In patients with neurological invasion,the 1-,2-,and 3-year survival rates were 49.0%,43.3%,and 14.4%,respectively,which were significantly lower than those without nerve invasion.Conclusion1.Preoperative biliary drainage,lymph node metastasis,postoperative radiotherapy,abdominal infection are factors affecting patient survival;2.Neurological invasion is an independent risk factor for the prognosis of pancreatic ductal adenocarcinoma.Part Two Next-generation sequencing to study the gene expression profile of pancreatic ductal adenocarcinoma and exploration of potential intervention targets Objective Based on next-generation sequencing technology,the unique mutational expression profile of pancreatic ductal adenocarcinoma pati-ents is established,which provides a theoretical basis for individualized targeted therapy.Methods Collection of 50 cases of formaldehyde-fixed paraffin tissue samples from 50 patients with pancreatic ductal adenocarcinoma under-going pancreaticoduodenectomy in the Department of Hepatobiliary Surgery,First Affiliated Hospital of Hunan Normal Universityfrom January 2016 to December 2018,using a high-throughput sequencing platform for 50 cases of cancer Genetic mutations in tissue and paracancerous tissue samples were subjected to deep targeted sequencing.Tumor cell variation,germline variation,tumor mutation load(TMB),microsatellite instability(MSI),single base mutation,insertion and deletion of small and large fragments of DNA,and gene copy number expansion Bioinformatics analysis was performed on the addition and loss,as well as gene fusion and rearrangement,and the gene mutation expression profile unique to the sample of this study was established.Based on this expression profile,an integrated search engine is used toeffectively integrate and analyze the human genome annotation database and related pharmacogenomic data-bases to identify potential intervention targets and related targeted drugs.Results 1.All pancreatic ductal adenocarcinoma samples have multiple genes and multiple types of mutations,each of which has different muta-tions and mutation sites.2.Based on gene sequencing,there were 4 pati-ents with gene fusion,2 patients with TMB-H,accounting for 7.6%.On MSI,they were all MSS and no positive PD-1 expression,suggesting the genes of these patients.Mismatch repair is complete and the efficacy of immun-otherapy for PD-1 antibodies may be poor.The top 5 mutant genes were 84.6% for KRAS,66% for TP53,19% for SMAD4,13% for CDK-N2 A and TGFBR2,and the KRAS gene was mainly point mutation.3.This study found that there are three G12 V,G12D,and G12 R in KRAS subtypes,and there is no difference in prognosis between patients with G12 V and G12 D and pancreatic ductal adenocarcinoma(P=0.575).Based on the gene mutation expression profile,five related mutations such as KRAS,TP53,CDKN2 A,APC and BRCA2 were found to be potential intervention targets.Currently,related drugs have entered the clinical trial stage.Conclusion1.All PDAC patients have multiple genes and multiple types of mutations,each of which has different mutation genes and sites.2.TMB-H,MSI,and PD-L1(CD274)positives were relatively low in this study,suggesting that the efficacy of immunotherapy for PD-1antibodies may be poor.3.There was no difference in the prognosis between the two subtypes of KRAS,G12 D and G12 V,in patients with pancreatic ductal adenocarcinoma.