Therapeutic effect of177
-Lys-BN in mice with PC-3 tumour xenografts. The graph shows the comparison of treatment with high specific activity (2 × 20 MBq/0.3 nmol peptide each; group D) and low specific activity (2 × 20 MBq/3.0 nmol peptide each; group C). Besides, it shows the effect of unlabelled DOTA-PEG5k-Lys-BN (2 × 3.0 nmol peptide; group B) on tumour growth. Data are expressed as the volume of tumour relative to the volume in the same animal immediately before the first injection (mean ± SD of six animals).