SSTR2 and neoplasm: The enhanced in vivo anti-tumour activity of [177Lu]Lu-satoreotide tetraxetan compared to [177Lu]Lu-DOTA-TATE observed in the present study can be partially explained by the ability of [177Lu]Lu-satoreotide tetraxetan to recognise almost twice as many SST2 binding sites as [177Lu]Lu-DOTA-TATE, as shown by our in vitro saturation binding assays using AR42J rat pancreatic tumour membranes (mean Bmax, 3210 fmol/mg protein for [177Lu]Lu-satoreotide tetraxetan versus 1790 fmol/mg protein for [177Lu]Lu-DOTA-TATE).