AFP and hepatocellular carcinoma: Results indicated that PLK4, as well as serum AFP level, tumor size, tumor multiplicity, tumor differentiation, clinical stage and vascular invasion, was responsible for efficacy of surgical treatment in HCC patient, by showing that PLK4 expression was significantly associated with overall survival (P = 0.002) and disease-free survival (P = 0.014) of HCC patients (Table 2).