title: Lessons on Tumour Response: Imaging during Therapy with (177)Lu-DOTA-octreotate. A Case Report on a Patient with a Large Volume of Poorly Differentiated Neuroendocrine Carcinoma.
abstract: Favourable outcomes of peptide receptor radiotherapy (PRRT) of neuroendocrine tumours have been reported during the last years. Still, there are uncertainties on the radionuclides to be used, the treatment planning, and the indication in patients with a high proliferation rate.This case report describes a patient with a high tumour burden of poorly differentiated neuroendocrine carcinoma of unknown primary with a proliferation rate in liver metastases up to 50%, undergoing fractionated treatment with 7 cycles of (177)Lu-DOTA-octreotate (7.4 GBq each) after disease progression on two different chemotherapy regiments. Based on initial staging scintigraphy, somatostatin receptor expression was very high.Longitudinal dosimetry studies during therapy indicated ongoing increases in tumour-to-organ ratios that coincided with an objective response.We conclude that fractionated therapy with (177)Lu-DOTA-octreotate should be considered a treatment option also for those patients with large tumours, high proliferation, and high receptor expression.
authors: 1. Nuclear medicine & PET, Uppsala University and Medical Sciences, Uppsala University Hospital, Uppsala, Sweden;
authors: Ulrike
authors: U
authors: Garske
authors: Mattias
authors: M
authors: Sandström
authors: Silvia
authors: S
authors: Johansson
authors: Dan
authors: D
authors: Granberg
authors: Hans
authors: H
authors: Lundqvist
authors: Mark
authors: M
authors: Lubberink
authors: Anders
authors: A
authors: Sundin
authors: Barbro
authors: B
authors: Eriksson