Lutetium-labelled peptides for therapy of neuroendocrine tumours

Treatment with radiolabelled somatostatin analogues is a promising new tool in the management of patients with inoperable or metastasized neuroendocrine tumours. Symptomatic improvement may occur with Lu-177-labelled somatostatin analogues that have been used for peptide receptor radionuclide therapy (PRRT). The results obtained with Lu-177-[DOTA(0),Tyr(3)]octreotate (DOTATATE) are very encouraging in terms of tumour regression. Dosimetry studies with Lu-177-DOTATATE as well as the limited side effects with additional cycles of Lu-177-DOTATATE suggest that more cycles of Lu-177-DOTATATE can be safely given. Also, if kidney-protective agents are used, the side effects of this therapy are few and mild and less than those from the use of Y-90-[DOTA(0),Tyr(3)]octreotide (DOTATOC). Besides objective tumour responses, the median progression-free survival is more than 40 months. The patients' self-assessed quality of life increases significantly after treatment with Lu-177-DOTATATE. Lastly, compared to historical controls, there is a benefit in overall survival of several years from the time of diagnosis in patients treated with Lu-177-DOTATATE. These findings compare favourably with the limited number of alternative therapeutic approaches. If more widespread use of PRRT can be guaranteed, such therapy may well become the therapy of first choice in patients with metastasized or inoperable neuroendocrine tumours.