In one study, Talimogene laherparepvec (also called T-VEC), an oncolytic HSV coding for granulocyte/macrophage-colony stimulating factor (GM-CSF), was administered by direct intratumoral injection to patients with metastatic malignant melanoma and this led to complete regressions of injected and uninjected lesions in eight of 50 patients [2]. This evidence concerns the gene CSF2 and metastatic melanoma.