Anti-angiogenesis seems have positive effects on tumor immune microenvironment. the combination of PD-1/PD-L1 inhibitors and TKIs exhibited favorable efficacy on gastrointestinal malignancies. Here the investigators want to examine the efficacy and survival benefit from the combination therapy to PD-1 acquired resistance patients, which turns out to be critical issues in recent years.
Immunotherapy acquired resistance was observed in clinical practice. The investigators intended to add anlotinib to PD-1 inhibitors, hoping reverse the resistance.