Abstract 311P
Background
Ampullary adenocarcinoma represents only 0.2% of gastrointestinal tumors and 7% of periampullary neoplasms. Generally, patients with ampullary adenocarcinoma have better oncologic outcomes when compared to other tumors of the biliary tract and pancreas. A higher incidence has been reported in the Hispanic population and has been associated with a higher hazard of death when compared to non-Hispanic white population. There are differences in survival depending on the histological subtype, with a median of 33 - 41 months in the pancreatobiliary subtype vs 72 - 80 months in the intestinal subtype.
Methods
Retrospective cohort study, evaluating 120 patients with ampullary adenocarcinoma clinical stages I - IV who received treatment at Instituto Nacional de Cancerología of Mexico between 2008 and 2021. Overall survival analysis was performed using Kaplan Meier test and Cox regression to determine independent predictive factors, using survival as the dependent variable and significant independent variables (p < 0.05) from univariate analysis.
Results
The median survival by histological subtype was 15 months (95% CI, 11.04 - 18.95) in the intestinal subtype and 13 months (95% CI, 8.43 - 17.52) in the pancreatobiliary subtype; Log Rank; p = 0.15. In the multivariate analysis, unresectable disease (HR = 2.89; 95% CI, 1.48 - 5.62; p = 0.002) and adjuvant chemotherapy (HR = 0.42; 95% CI, 0.27 - 0.66; p = 0.001) were independent predictive factors of survival.
Conclusions
Overall survival was not significantly different between patients with ampullary adenocarcinoma with intestinal subtype vs pancreatobiliary subtype. Disease stage and adjuvant therapy are independent predictive factors of survival. The prevalence of microsatellite instability (MSI) has been identified in 18% of the population and HER2 amplification in 13 - 23% of cases. These biomarkers appear promising.
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.