Clinical protocols of ACT infusing ex vivo expanded tumor-infiltrating lymphocytes (TIL) or T cell receptor (TCR) engineered peripheral blood T cells require the concomitant administration of interleukin 2 (IL-2, aldesleukin), usually administered intravenously at the highest tolerated dose every 8 h in an inpatient hospital setting to support expansion and function of the adoptively transferred cells2. This evidence concerns the gene IL2 and neoplasm.