Evaluation of Circulating Immune Response After Histosonics in Colorectal Cancer (ECHO-CRC)

This is a single-center, non-randomized, open-label, single-arm pilot study investigating the systemic immune response to histotripsy in patients with colorectal cancer with liver metastasis. Histotripsy is an FDA-approved, non-invasive therapeutic modality for the treatment of liver tumors, including both primary and metastatic lesions. In this study, investigators aim to evaluate the kinetics of peripheral T-cell response following histotripsy of colorectal cancer liver metastases (CRCLM). Given the well-documented immune-tolerant tumor microenvironment of liver metastases and their role in systemic resistance to checkpoint inhibitors, investigators hypothesize that histotripsy-induced tumor disruption will lead to measurable alterations in peripheral T-cell clonal expansion and exhaustion markers. Investigators will assess these changes via serial blood draws before and after histotripsy, with the goal of characterizing the systemic immune impact of local tumor ablation. Findings from this study may inform future combination strategies integrating histotripsy with immunotherapy to enhance treatment response in microsatellite-stable CRC