AFP and hepatocellular carcinoma: Notably, CTC burden seems to be a better readout of response for the patient with HCC (HB83/114/116, Figure 6), who showed an increase in CTCs between hepatectomy and metastasectomy procedures when it was clear that they still had disease present by imaging; during the same timeframe, AFP levels for this patient dropped from 10.5 to 2.1.