PDCD1 and gastroesophageal junction adenocarcinoma: In another study from 2023, Zhang et al. [46] aimed to investigate the safety and efficacy of apatinib (a tyrosine kinase inhibitor) and sintilimab (anti-PD-1 mAb) in combination with chemotherapy as a second- or third-line treatment for patients with previously treated and non-responsive advanced G/GEJ adenocarcinoma (Table 2).