AFP and hepatocellular carcinoma: In this analysis, the CTC number in peripheral blood was associated with AFP level (P = 0.0041), tumor number (P < 0.0001), largest tumor diameter (P = 0.0003), MVI (P < 0.0001), thrombosis (P < 0.0001), AJCC stage (I vs. II, P < 0.0001; II vs. III, P < 0.0001; I vs. III + IV, P < 0.0001), and BCLC stage (A vs. B, P < 0.0001; B vs. C, P < 0.0001; B vs. C, P < 0.0001), indicating that CTC number was associated with HCC tumor burden and could be used to assess HCC progression (Figure 3A, Table S5).