Collectively, our observations indicated that for both peritoneal and liver metastasis of CRC, 68Ga-FAPI PET imaging is valuable in monitoring responses to therapy with combined TGF-β inhibitor and ICBs, and 68Ga-FAPI and 18F-FDG double-tracer PET/CT imaging is superior to single-probe PET imaging in immune-therapeutic management of colorectal liver metastasis. The gene discussed is TGFB1; the disease is colorectal carcinoma.