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 distal cholangiocarcinoma remains a clinical challenge. Recent studies have shown important differences in terms of survival between these tumors. Therefore, different treatments should be considered, but the preoperative histological diagnosis is still difficult. Aim of this study is to create a preoperative diagnostic score for differential diagnosis between primary pancreatic adenocarcinoma and primary distal cholangiocarcinoma.

Methods: One hundred eighty consecutive patients who underwent pancreaticoduodenectomy at Sapienza University of Rome from January 2010 to December 2019 were retrospectively analyzed. Inclusion criteria were pancreatic or biliary histologic origin obtained by definitive postoperative histological examination. Exclusion criteria were diagnosis of ampullary carcinoma, non-ampullary duodenal adenocarcinoma, pancreatic metastasis, and benign disease. One hundred one patients were considered eligible for the retrospective study. Preoperative biological, 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 logistic analysis. Multivariate logistic analysis has shown that parameters independently associated with primary pancreatic adenocarcinoma 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 primary pancreatic 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 pancreatic cancer histologic origin and to improve target therapeutic strategy.