The next step for a patient with an elevated Carbohydrate Antigen 19-9 (CA19-9) level is to perform imaging studies, such as abdominopelvic CT, to determine the underlying cause of the elevation, as CA19-9 levels alone are insufficient to make a diagnosis 1. When evaluating a patient with an elevated CA19-9 level, it is essential to consider the following:
- The patient's clinical presentation and medical history to determine the likelihood of pancreatic cancer or other malignancies 1
- The possibility of benign conditions, such as obstructive jaundice, that can cause elevated CA19-9 levels 1
- The use of abdominopelvic CT to detect underlying conditions, including malignancies and benign diseases, that may be causing the elevated CA19-9 level 2 Key points to consider when interpreting CA19-9 levels include:
- A CA19-9 level of <100 U/ml may indicate resectable disease, while levels >100 U/ml may suggest unresectability or metastatic disease 3
- Normalization or a decrease in post-operative CA19-9 levels by ≥20-50% from baseline following surgical resection or chemotherapy is associated with prolonged survival 3 It is crucial to note that CA19-9 levels should not be used as a screening test for pancreatic cancer, as they are not specific for this disease and can be elevated in various other conditions 1. In patients with elevated CA19-9 levels, a thorough evaluation, including imaging studies and clinical assessment, is necessary to determine the underlying cause and guide further management 1, 2.