GPI and hepatocellular carcinoma: Figure 4D shows the correlation between DU from HCCs at different stages of tumor growth and the number of double bonds in phantom. DU of all three HCC groups and control liver did not differ significantly (P > 0.05) before 20 weeks. At 25–30 weeks, although the tumors were not observed, the DU of HCCs (Gp-I and III) were significantly reduced (P < 0.05) compared with normal liver (Table 2).