Pancreatic ductal adenocarcinoma and distal cholangiocarcinoma: a proposal of preoperative diagnostic score for differential diagnosis

Purpose:The differential diagnosis between primary adenocarcinoma of the pancreas head and distalcholangiocarcinoma remains a clinical challenge. Recent studies have shown important differences in terms ofsurvival between these tumors. Therefore, different treatments should be considered, but the preoperativehistological diagnosis is still difficult. Aim of this study is to create a preoperative diagnostic score for differentialdiagnosis between primary pancreatic adenocarcinoma and primary distal cholangiocarcinoma.Methods:One hundred eighty consecutive patients who underwent pancreaticoduodenectomy at SapienzaUniversity of Rome from January 2010 to December 2019 were retrospectively analyzed. Inclusion criteria werepancreatic or biliary histologic origin obtained by definitive postoperative histological examination. Exclusion criteriawere diagnosis of ampullary carcinoma, non-ampullary duodenal adenocarcinoma, pancreatic metastasis, andbenign disease. One hundred one patients were considered eligible for the retrospective study. Preoperativebiological, clinical, and radiological parameters were considered.Results:CRP > 10 mg/dL (p= 0.001), modified Glasgow Prognostic Score 2 (p= 0.002), albumin < 35 g/L (p= 0.05),CA 19-9 > 230 U/mL (p= 0.001), and Wirsung diameter > 3 mm (p< 0.001) were significant at univariate logisticanalysis. Multivariate logistic analysis has shown that parameters independently associated with primary pancreaticadenocarcinoma were CRP > 10 mg/dL (p= 0.012), CA 19-9 > 230 U/mL (p= 0.043), and diameter of the Wirsung> 3 mm (p= 0.005). Through these parameters, a diagnostic score has been developed to predict a primarypancreatic adenocarcinoma when > 1 and a primary distal cholangiocarcinoma when < 1.Conclusion:This feasible and low-cost diagnostic score could have a potential impact to differentiate pancreaticcancer histologic origin and to improve target therapeutic strategy.