The feature of this series of cases was that after the failure of the original chemotherapy regimen, the patients with MSS/pMMR advanced GI tumors were treated using apatinib combined with camrelizumab, which induced a systemic inflammatory response (characterized by sharply increased CRP and emergence of systemic rash, oral ulcer, and gingivitis), and further combination with chemotherapy achieved good results. The gene discussed is CRP; the disease is gingivitis.