Inclusion Criteria:  Scheduled and indicated for standard-of-care liver tissue ablation for either hepatocellular carcinoma (HCC) or metastatic liver tumor(s) using either RF or MW energy. At least 21 years of age Single tumor, or multiple tumors only if the distance between the ablated tumor and all other tumors is at least 8 cm Distance between the tumor and the edge of any previous necrotic zones is at least 5 cm. Single ablation, using a single ablation needle, per tumor. Able and willing to give informed consent.  Exclusion Criteria:  Liver tumor that cannot be ablated with a single ablation needle, according to the Investigator's clinical discretion. Subject cannot tolerate/undergo contrast-enhanced CT (e.g., due to contrast media allergy) Planned ablation includes adjunctive means other than RF or MW energy (e.g., ethanol, hepatic artery embolization, etc.) or overlapping ablations using a single ablation needle. Ablation area cannot be visualized continuously using ultrasound throughout the entire ablation procedure. Pregnant or lactating Currently participating in another clinical trial of an unapproved investigational device or drug that has not concluded the follow-up period. Unable or unwilling to give informed consent.