Decreased serum carbohydrate antigen 19–9 levels after neoadjuvant therapy predict a better prognosis for patients with pancreatic adenocarcinoma: a multicenter case-control study of 240 patients

Background Carbohydrate antigen (CA) 19–9 levels after resection are considered to predict prognosis; however, the significance of decreased CA19–9 levels after neoadjuvant therapy has not been clarified. This study aimed to define the prognostic significance of decreased CA19–9 levels after neoadjuvant therapy in patients with pancreatic adenocarcinoma.