Cryoablation Combined with Sintilimab Plus Regorafenib in Previously Treated Colorectal Cancer Liver Metastasis

Sintilimab plus regorafenib will be initiated on day 14 after cryoablation. Sintilimab will be administered at 200 mg i.v. every 3 weeks.

Regorafenib will be initiated on day 14 after cryoablation. Regorafenib 80 mg was given orally once daily on days 1-21 of a 28-day cycle until documented disease progression, development of unacceptable toxicity, participant request, or withdrawal of consent.

Cryoablation will be performed with a two-cycle freeze-thaw phase protocol; US or non-contrast CT images will be obtained to visualize the evolving ablation zone