CTLA4 and neoplasm: Kükköse et al. developed an innovative model for spontaneous multiorgan metastasis in high microsatellite instability CRC tumors by transplanting patient-derived organoids into the cecum of humanized mice and analyzed the relationship between the therapeutic effects of anti-PD-1 and anti-CTLA-4 and the immune background of primary tumor, liver metastasis and peritoneal metastasis [42].