Combination of TATE and PD-1 Inhibitor in Liver Cancer

1. Patients with a confirmed diagnosis of (1) advanced HCC or (2) metastatic gastric cancer. 2. Patients between ages 18 and 80 3. If HCC patients, they should have progressive disease (PD) on an immune therapy for advanced HCC. For patients with metastatic gastric cancer, they should have failed at least one line of systemic chemotherapy and an immune checkpoint inhibitor. 4. Patients with liver tumor lesions with at least one with a diameter of 2 cm or bigger, which is amendable for (super-)selective TATE as the target lesion. 5. ECOG score 2 or less 6. Child-Pugh scores 5-7 for HCC patients 7. All prior chemotherapy at least 4 weeks prior to study treatment. Immunotherapy not subject to this limitation. 8. No major GI bleeding in the prior 2 months. 8\. Hgb\>=8, platelet \>= 50,000, Cr =\< 2, AST and ALT \< 10 X ULN, t-Bilirubin \< 3, 9. Patients with a history of major autoimmune disorders excluded.