GZMB and colonic neoplasm: We investigated the use of a granzyme B targeted peptide (GZP) as a cancer theranostic agent, radiolabeled with 68Ga (68Ga-GZP) as a PET imaging agent and radiolabeled with 90Y (90Y-GZP) as a targeted radionuclide therapy agent for combinational therapy with ICI in murine models of colon cancer.