ICOS and gastrointestinal stromal tumor: In Dufresne et al, ICOS (Inducible T-cell costimulator) and GITR (glucocorticoid-induced tumor necrosis factor receptor) seemed to be of major interest in all studied histotypes, as was OX40 in synovialosarcoma and CD40 in GIST and synovialosarcoma based on RNA-sequencing data (76).