Elevated CA 19-9 is associated with worse survival in patients with resected ampullary adenocarcinoma

Background: The prognostic utility of Carbohydrate Antigen 19-9 (CA 19-9) and Carcinoembryonic Antigen (CEA) in ampullary adenocarcinoma is unclear. We sought to evaluate the association between initial tumor marker levels and survival in patients with resected ampullary adenocarcinoma.Methods: This was a single-institution, retrospective cohort study of consecutive patients who underwent pancreatoduodenectomy for ampullary adenocarcinoma from 1999 to 2021. CA 19-9 was assessed after biliary decompression. Contal and O'Quigley method determined optimal biomarker cutoff levels which were correlated with overall survival (OS) using the Kaplan-Meier method and Cox Proportional Hazards Regression.Results: A total of 180 patients underwent pancreatoduodenectomy. Patients with CA 19-9 >100 U/mL had a shorter median OS (28 vs. 132 months, p < 0.001) compared to patients with CA 19-9 <= 100 U/mL at diagnosis. Survival was similar between pancreaticobiliary and intestinal tumor subtypes when CA 19-9 was >100 U/mL (OS:25 vs. 33 months, p = 0.415). By Cox regression analysis, CA 19-9 >100 U/mL was independently associated with worse OS (HR 2.8, p = 0.001). Conclusions: Preoperative CA 19-9 >100 U/mL was associated with shorter OS in patients with resected ampullary adenocarcinoma. CA 19-9 may be useful when counseling patients about prognosis or when considering the role of perioperative systemic therapy.