Background: The aim of this study was to assess the efficacy and toxicity of peptide receptor radionuclide therapy (PRRT) with the use of the high affinity somatostatin receptor subtype 2 analogue, (90)Y labelled Tyr3-octreotate, ((90)Y-DOTATATE) in neuroendocrine tumours (NETs).
Material and methods: 46 patients with disseminated or non-operable NET were enrolled in this study. The (90)Y-DOTATATE therapeutic activity was calculated per total body surface area up to a total of 7.4 GBq/m(2) administered in three to five cycles, repeated every four to nine weeks. Before and after the therapy, blood tests for haematology, kidney and liver function, and chromogranin A were performed.
Results: Out of 46 (90)Y-DOTATATE treated patients, one died before completing the therapy and 16 died after completing the therapy, among them one due to myocardial infarction. After 12 month follow-up, stabilisation of disease was observed in 47%, partial remission in 31%, and progression in 9% of the 45 patients who completed the therapy. Five patients died before completion of 12 months of follow-up. One of the patients died due to myocardial infarction. In one case, the information after 12 months is incomplete. The progression free survival was 37.4 months. During 12 months follow-up, transient decrease of PLT, WBC and haemoglobin values was observed. A transient increase of creatinine level (within normal ranges) and decrease of GFR values were found.
Conclusions: NETs (90)Y-DOTATATE therapy results in symptomatic relief and tumour mass reduction. The mild critical organ toxicity does not limit the PRRT of NETs.