PDCD1 and gastric cancer: This rate of PD-L1 positivity is similar to that found in a report informed in the American Society of Clinical Oncology of 2015, in which PD-L1 was detected in 40% of advanced GC received the treatment of the PD-1 monoclonal antibody, pembrolizumab (PD-L1 out-off value: >1%) [13].