Keratin 19 protein expression is an independent predictor of survival in human hepatocellular carcinoma

Aim We aimed to assess the clinicopathological relevance and prognostic significance of expression of the hepatic progenitor cell markers keratin 19 (K19), epithelial cell adhesion molecule (EpCAM) and CD117 (c-KIT) in a White series of hepatocellular carcinoma (HCC). Methods We evaluated the immunohistochemical expression of K19, EpCAM and CD117 in 89 surgical specimens of HCC from Greek patients (mean age 66.7±11.3 years, male 75.2%) followed up for 39.6±25.3 months. Results K19, EpCAM and CD117 expression was detected in tumour cells of 10.11, 15.38 and 3.7% HCCs, respectively. Female sex was correlated with EpCAM immunohistochemical expression (P=0.035), whereas no other significant relationship with clinicopathological parameters was observed. K19 positivity tended to be correlated with microvascular invasion (P=0.054). In univariate analysis, K19 positivity and microvascular invasion were found to be associated with decreased recurrence-free survival (P<0.001 and P=0.004, respectively) and overall survival (P=0.002 and P=0.029, respectively). EpCAM and CD117 positivity was not correlated with patient survival. In multivariate analysis, K19 positivity emerged as an independent predictor of recurrence-free survival (odds ratio=7.84, 95% confidence interval=2.658-22.912, P<0.001) and overall survival (odds ratio=3.845, 95% confidence interval=1.401-10.549, P=0.009). Conclusion Our study confirms the prognostic significance of K19 expression in Caucasian patients with HCCs, providing further evidence that it may be used to stratify HCC according to tumour aggressiveness.