Specifically, inhibitors targeting programmed cell death protein 1, such as KEYTRUDA® (pembrolizumab), have demonstrated promising clinical benefits in several well-designed trials.[2,16] In 2021, phase II trials were conducted to assess the effectiveness of pembrolizumab in patients with advanced small bowel cancer.[2] However, the efficacy of pembrolizumab in treating SBCs is still under debated and controversial. Here, PDCD1 is linked to small intestine carcinoma.