A wide range of other DIT has been trialled within the context of recurrent HNSCC, including Poly-ICLC [22], cisplatin/epinephrine injectable gel [11], interleukin-2 therapy [23], mycobacterial heat-shock protein 65 [24], CAR-T [25] and microorganism-based IT treatments including oncolytic viruses [19, 26], plasmids [27, 28], and bacteria [29, 30]. Here, IL2 is linked to head and neck squamous cell carcinoma.