T‐VEC is a live attenuated genetically modified HSV designed for replication in tumor cells and local expression of granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) by the infected tumor cells, which is proposed to enhance tumor antigen presentation to the immune system, inducing immune responses to the tumors, but the exact mechanism of action is not known [27, 28, 29]. Here, CSF2 is linked to neoplasm.