ISSN:
1569-8041
Keywords:
octreotide
;
peptide
;
radionuclide
;
scintigraphy
;
somatostatin
;
therapy
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract Background: Peptide receptor scintigraphy with the radioactive somatostatin analogue, [111In-DTPA0]octreotide, is a sensitive and specific technique to show in vivo the presence and abundance of somatostatin receptors on various tumours. Aim: With this technique primary tumours and metastases of neuroendocrine cancers as well as of many other cancer-types can be localised. This technique is currently used to assess the possibility of peptide receptor radionuclide therapy (PRRT) with repeated administrations of high doses of [111In-DTPA0]octreotide. 111In emits Auger and conversion electrons having a tissue penetration of 0.02–10 µm and 200 to 500 µm, respectively. Patients and methods: Thirty end-stage patients with mostly neuroendocrine progressing tumours were treated with [111In-DTPA0]octreotide, up to a maximal cumulative patient dose of about 74 GBq, in a phase I trial. Results: There were no major clinical side effects after up to two years treatment, except that in a few patients a transient decline in platelets counts and lymphocyte subsets occurred. Promising beneficial effects on clinical symptoms, hormone production and tumour proliferation were found. Of the 21 patients who received a cumulative dose of more than 20 GBq, eight patients showed stabilisation of disease and six other patients a reduction in size of tumours. There is a tendency towards better results in patients whose tumours have a higher accumulation of the radioligand. Conclusions: PRRT is feasible, also with 111In as radionuclide. Depending on the homogeneity of distribution of tumour cells expressing peptide receptors and the size of the tumour, β-emitting radionuclides, e.g., 90Y, labelled to DOTA-chelated peptides, are also attractive candidates for PRRT. The first PRRT trials with [90Y-DOTA0,Tyr3]octreotide started recently.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1027396313397
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