Consequently, in patients with a low percentage of PD-L1+ leukocytes (PD patients), the administration of anti-PD-(L)1 treatment may confer no therapeutic benefit as the tumor may be employing alternative immune evasion mechanisms such as TIM-3/Galectin-9 [28] or TIGIT/CD155 [29,30]. This evidence concerns the gene TIGIT and neoplasm.