Fig. 2C shows the HE and anti-AFP staining of Regions 1, 2, and 3 in the MRI images at the tenth hour. They show that anti-AFP MNPs, (represented by brown spots in the macroscopic anti-AFP staining photos) accumulated in HCC sites for the area ratio, defined as the area of brown spots over of the whole macroscopic photo (approximately 5–10%). This proves the superior sensitivity of SSB for the detection of few anti-AFP MNPs in livers (around several 10−2 emu/g, which was obtained by calibrating the results of SSB in vitro test with the SSB results of anti-AFP MFs possessing known M). This evidence concerns the gene AFP and hepatocellular carcinoma.