CA 19-9 and CEA in prognosis of duodenal adenocarcinoma: A retrospective study

A new research paper titled "Importance of carbohydrate antigen (CA 19-9) and carcinoembrionic antigen (CEA) in the prognosis of patients with duodenal adenocarcinoma: a retrospective single-institution cohort study" has been published in Oncotarget.

Duodenal adenocarcinoma (DA) is a rare malignancy without validated tumor markers. In practice, carcinoembryonic antigen (CEA) and carbohydrate antigen (CA 19-9) are often used in the management of DA, though their prognostic value is unknown.

In this new study, researchers from the University of Florida, University of Florida Health Cancer Center and University of Alabama at Birmingham conducted a single-institution retrospective review including patients diagnosed with biopsy-confirmed adenocarcinoma of the duodenum between 2006 and 2021.

"To our knowledge, this is the first study to evaluate the role of tumor markers in patients with DA. In fact, this is the largest single institution study in the US evaluating this disease," the researchers write.

Peri-ampullary tumors were excluded. Levels of CA 19-9 and CEA were collected as continuous variables and were analyzed as binary variables: normal vs. high, using the maximum normal value as a cut-off (normal Ca 19-9 <35 U/ml; CEA <3 ng/ml). Survival analysis was conducted using Kaplan-Meier curves, log-rank test and Cox proportional hazards model.

There were 68 patients included in the final analysis. Median age was 67 years old and median follow-up time was 22.2 months. CA 19-9 and CEA were elevated in 36.8% and 48.5% of patients, respectively. A concomitant elevation of both tumor markers was associated with worsened OS (HR 2.140, 95% CI: 1.114–4.112; p = 0.019). After controlling for age and sex on multivariate analysis, elevation in both CA 19-9 ≥35 and CEA ≥3.0 remained significantly associated with increased mortality (HR 2.278, 95% CI: 1.162–4.466; p = 0.016).

"In summary, CA 19-9, and to a lesser extent, CEA, show promise as prognostic markers in DA. Larger studies are needed to validate their use and to evaluate their performance as markers of recurrence," the researchers conclude.