However, the immune checkpoint inhibitors (ICIs) targeting PD-(L)1 and/or CTLA-4 have not seen clinical meaningful anti-tumor effects in gastroenteropancreatic (GEP) -NETs, except for the rare subsets of patients with MSI-H or TMB-H (Mehnert et al. 2020, Patel et al. 2020, Chan et al. 2021). The gene discussed is CTLA4; the disease is neoplasm.