[en] As meanwhile demonstrated by different groups, a variety of human tumours express a large number of peptide receptors with a high affinity for VIP and SST. Radiolabeled synthetic analogs of these peptide hormones have been shown to be effective in diagnosis of SST receptor positive tumours and metastases. This fact seems to be a promising starting point for the therapeutic use of this cancer seeking tracer molecules for targeted radiotherapy. In this project we have focused our work on the preparation of DOTA-Lanreotide (Mauritius), a novel SST analog, which shows a high affinity to several SST receptors expressed by neuroendocrine tumours. This radiolabeled tracer actually is under evaluation by a European multicenter study for its diagnostic and therapeutic capacity