Fig. 1From: Combination regimens with PD-1/PD-L1 immune checkpoint inhibitors for gastrointestinal malignanciesLimitations of PD-1/L1 blockade monotherapy and advantages of combination immunotherapy. There are currently many limitations of single-drug therapy with PD-1 inhibitors, including the five aspects shown above, but combined immunotherapy may help to solve some of the limitations of single-drug therapy. Specific combination immunotherapy strategies include combined radiotherapy, chemotherapy, targeted therapy, and another related immunotherapyBack to article page