Objectives: Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths worldwide. CA19-9 is a glycoprotein that predicts poor prognosis in pancreatic and biliary malignancies. We evaluated it as a prognostic biomarker for patients with HCC.
Methods: We prospectively enrolled 145 patients with HCC, diagnosed using American Association for Study of Liver Diseases criteria, between October 2008 and November 2012. We examined whether baseline serum CA19-9 levels predicted overall survival. We also examined immunostains of hepatic resections and explants of patients with elevated and normal serum CA19-9.
Results: In a cohort of predominantly hepatitis C and B patients, CA19-9 ≥100 U/ml was associated with a 2.7-fold increased mortality (hazard ratio (HR): 2.72; 95% confidence interval (CI): 1.52-4.88, P<0.001). It remained a significant predictor (HR: 2.58; 95% CI: 1.41-4.72, P=0.002) in a multivariable model adjusted for Child-Pugh score, alpha-fetoprotein, Barcelona Clinic Liver Cancer stage, and Model for End-Stage Liver Disease. CA19-9 immunohistochemistry performed on a subset of liver resection and explant specimens showed increased CA19-9 immunostaining of non-tumor liver parenchyma in patients with elevated serum CA19-9. It also showed staining of native and reactive bile ducts, and of progenitor-like cells at the periphery of cirrhotic nodules.
Conclusions: Elevated serum CA19-9 ≥100 U/ml is an independent predictor of poor overall survival in this hypothesis-generating study. The unfavorable prognosis seen with elevated serum levels may be related to progenitor-like cells in the non-tumor liver.