A high tumor burden is associated with greater systemic and tumor inflammation. MTV was calculated from baseline positron emission tomography and divided into patients with low MTV (<150 mL) or high MTV (>150 mL) as previously described.³⁷  (A) Comparison of ferritin levels (n = 67) before axi-cel infusion between patients with low or high MTV as shown. Comparison of cytokine levels (n = 58) at day 0 before axi-cel infusion (B) and at the peak level after axi-cel infusion (C). Comparison of MTV with peak axi-cel expansion (n = 42) (D) and baseline percentage M-MDSC levels (n = 33) (E). (F) Comparison of selected IFN signaling target genes in the baseline TME (n = 26). Shown are IFI6 and IFIT1. All P values by nonparametric Mann-Whitney t tests. *P < .05; **P < .01. mRNA, messenger RNA; NS, not significant.