MSLN and neoplasm: The anti-MSLN VH-Fcs (2A10, 3C9) and IgG1m912 demonstrated accumulation within the MSLN-positive HCT116 tumor,with the highest uptake occurring at 18 h for [89Zr]Zr-VH-Fc3C9 (1.07 ± 0.48 SUVmean) and [89Zr]Zr-m912(0.86 ± 0.12 SUVmean) followed by slight decreasesover the 144 h window (Table 2, Figure 4).[89Zr]Zr-VH-Fc 2A10 achieved the highest accumulation at48 h (2.08 ± 0.60 SUVmean), and consistently demonstratedsignificantly higher tumor uptake than [89Zr]Zr-m912 (p ≤ 0.05) at all time points (90 m not applicable)and [89Zr]Zr-VH-Fc 3C9 (p ≤ 0.001)at 18 and 48 h.