OBJECTIVETo investigate the expression of CK19 in HBV-related hepatocellular carcinoma (HCC) tissues in patients with low serum AFP concentration and the relationship between them and the recurrence and prognosis of HCC after R0 radical hepatectomy.

METHODSThe expressions of CK19 and Ki67 in HCC tissues of 235 cases were examined using tissue microarray and two-step methods of PV-6000 immunohistochemistry. The expression of CK19 mRNA in 20 frozen HCC specimens was examined by RT-PCR. The correlation between gene expressions and tumor recurrence and prognosis was analyzed.

RESULTSAmong the 235 HBV-related HCC patients after R0 radical hepatectomy, the median disease-free survival (DFS) was 31.2 months in the patients with serum AFP < 400 µg/L and 13.8 months in the patients with serum AFP ≥ 400 µg/L (P = 0.041), the overall survival (OS) was 84.0 and 58.6 months in the two subgroups (P = 0.125), and the tumor recurrence within one year was in 43 cases (27%) and 37 cases (49.3%), respectively, (P = 0.001). The DFS was 11.6 months in the CK19-positive cases and 27.0 months in the CK19-negative cases (P > 0.05). The OS was significantly lower in the CK19-positive cases than that in the CK19-negative cases (P = 0.023). Both DFS and OS in the CK19-positive cases with AFP < 400 µg/L were significantly lower than those in the CK19-negative cases with AFP < 400 µg/L (both P < 0.05). The CK19 expression was significantly correlated with histological differentiation (P = 0.023), number of tumor foci (P = 0.044), vascular tumor embolism (P = 0.005), regional lymph node metastasis (P = 0.023), and 1-year recurrence (P = 0.006). Among the patients with AFP < 400 µg/L, the 1-year recurrence was 53% in the CK19-positive cases and 23% in the CK19-negative cases (P < 0.001), the median DFS was 11.3 months in CK19-positive cases and 34.0 months in CK19-negative cases (P = 0.010), and the median OS was 19.5 months in the CK19-positive cases, significantly lower than 84.0 months in the CK19-negative cases (P = 0.001). Cox regression analysis showed that CK19-positive expression was an independent factor affecting early HCC recurrence and prognosis.

CONCLUSIONIn HBV-related HCC patients after radical hepatectomy with AFP < 400 µg/L, positive expression of CK19 indicates a higher proliferation and invasiveness of HCC, and is an important factor of early recurrence and poor prognosis.