AFP and hepatocellular carcinoma: Hartenbach and colleagues employed PET/CT with 18F-fluoroethylcholine in 24 patients with locally advanced HCC and initially elevated AFP level; from semiquantitative analysis, increased SUV mean at diagnosis, decreased SUV max and in tumor-to-background ratio after 90Y-therapy (i.e., Δmaximum SUV and Δtumor-to-background ratio, respectively) showed the highest area under the curve to predict patient response [23].