Background: The expression of CK19 in primary hepatocellular carcinoma (HCC) is associated with a poor outcome. However, few studies have investigated the expression profile of CK19 in regional lymph nodes (LNs) of HCC after hepatic resection. The purpose of this study was to evaluate the expression of CK19 in primary liver tumor and regional LNs of HCC with and without lymph node metastasis (LNM).
Methods: The expression of CK19 in patients with (n = 16) and without LNM (n = 26) was examined using immunohistochemical staining. Both the primary tumor and LN specimen were studied for their CK19 expression. Clinico-pathological variables and prognostic significance were analyzed.
Results: Immunopositivity of CK19 in primary liver tumor was significantly correlated with LNM (P = 0.005) and tumor non-encapsulation (P <0.005). Univariate analysis showed that CK19 expression in primary liver tumor, CK19 expression in regional LN, vascular invasion, daughter nodules, positive resection margin and American Joint Committee on Cancer (AJCC) tumor stage significantly decreased overall survival. Multivariate analysis demonstrated that daughter nodules (P = 0.001) and CK19 expression in regional LN (P = 0.002) were independent prognostic factors for overall survival.
Conclusions: This study showed that CK19 expression in regional LN of HCC was associated with LNM and an extremely poor outcome after operation. It is of clinical significance to identify these patients at risk for more aggressive HCC, and multi-modality treatment could be helpful to improve their dismal outcome.