Treat-and-resect Study of Echo Decorrelation Imaging-controlled Radiofrequency Ablation in Liver Tumors

To rigorously test the feasibility of 3D echo decorrelation imaging to improve the reliability of clinical thermal ablation, decorrelation-controlled ablation will be assessed in a pilot treat-and-resect study. Patients previously scheduled for resection of metastatic liver tumors or benign liver tumors physiologically similar to hepatocellular carcinoma (HCC) (e.g., hepatocellular adenoma or focal nodular hyperplasia) will first undergo radiofrequency ablation (RFA) of their tumors, with real-time, 3D ultrasound echo decorrelation imaging of the treated region performed throughout each ablation. RFA will be performed in the same surgical procedure as the scheduled tumor resection, immediately prior to resection. Patients will be enrolled in two arms, the first undergoing RFA controlled by the RFA generator using manufacturer-specified algorithms, and the second undergoing RFA with echo decorrelation imaging providing an additional stopping criterion. For both arms, 3D maps of ablation zones will be constructed from stained tissue sections and rigidly registered to volumetric ultrasound images using the known tumor position and orientation relative to the ultrasound image volume. Overall ROC curves for prediction of local treatment will be constructed using point-by-point comparison of 3D echo decorrelation images to the mapped ablation zone. The ability of echo decorrelation to predict and control clinical thermal ablation of human liver tumors will be directly tested by assessing and statistically comparing outcomes of the two study arms, including ROC curves, ablation volume and rate, and conformity to planned ablation zones.