A Trial Utilizing 18F-FS PG PET to Guide Therapy in Hepatocellular Carcinoma

To evaluate the relationship between 18F-FSPG uptake in HCC lesions, ctDNA in blood and clinical response to Y90 radioembolization therapy in patients with hepatocellular carcinoma (HCC) by SOC imaging.

Inclusion Criteria: 1. Diagnosis of HCC with one or more of the following: 1. Liver mass with non-rim arterial phase hyperenhancement (APHE) and one of the following: 1. 10-19 mm with ≥ 2 additional major features according to LI-RADS criteria ("washout", enhancing "capsule", and/or threshold growth), 2. 10-19 mm with "washout" and visibility at antecedent ultrasound (US) but with no "capsule" or threshold growth, 3. 10-19 mm with ≥50% size increase in ≤6 months but with no "washout" or "capsule" or 4. ≥20 mm with ≥1 additional major feature according to LI-RADS criteria ("washout", enhancing "capsule", or threshold growth). 2. Lesions that meet LI-RADS 4 criteria or 3. Lesions that meet LI-RADS 5 criteria or 4. Suggestive imaging findings plus Alpha Fetoprotein (AFP) \> 200 mg/dL or 5. Tumor confirmed by arteriography or 6. Pathologic confirmation of tumor and 2. Patients with HCC must be a candidate for Y90 radioembolization monotherapy. and 3. Each patient must have completed conventional imaging and staging and CT before initiation of the investigational PET studies. 4. Age ≥18 years. Because no dosing or adverse event data are currently available on the use of 18F-FSPG in patients \ 200 mg/dL). 5. Patients with psychiatric illness/social situations that would limit compliance with study requirements. 6. Patients who have not recovered from AEs or had allergic reactions to similar compounds should be excluded.