Surprisingly, PDGFRA-mutant GISTs showed an increased number of immune cells, compared with c-KIT-mutant GIST, and an overexpression of stimulatory cytokines (e.g., CXCL14) which additionally activate NK+, CD4+, and CD8+ cells, leading to tumor regression [5]. This evidence concerns the gene KIT and gastrointestinal stromal tumor.