FOLH1 and neoplasm: In a study, Grubmüller et al. retrospectively investigated the use of PET/CT with [68Ga]Ga-PSMA-11 in 177Lu-PSMA therapy and could show that the total tumor volume (TTV) in PET seems to be a reliable parameter for response assessment, especially since the change of TTV under therapy was also linked to overall survival [154].