Immune checkpoint receptor pathwayblockade monoclonal antibodies such as anti-PD-1, anti-PD-L1, andanti-CTLA-4 can reverse T effector (Teff) cell dysfunctionand exhaustion, resulting in dramatic tumor shrinkage and sometimescomplete remission in some patients, even with late stage metastaticdiseases.1,2 However, the response rate varies greatlybetween tumor types: up to 40% in melanoma, 25% in non-small celllung cancer, but <10% in most other tumor types. This evidence concerns the gene CTLA4 and neoplasm.