Xenograft cancer studies using rag2Δ/Δ, il2rga−/− zebrafish allow facile, single-cell imaging of T cell–mediated tumor killing by CAR T cell, BiTE, and APEC immunotherapies and identified EGFR-targeted immunotherapies as an effective treatment for rhabdomyosarcoma muscle cancers. This evidence concerns the gene EGFR and cancer.