Impact of a commercial 3D OSEM reconstruction algorithm on the 177Lu activity quantification of SPECT/CT imaging in a Molecular Radiotherapy trial

Elisa Grassi ,Emilio Mezzenga ,Federica Fioroni ,Sarti Ma ,Angelina Filice ,Annibale Versari ,Domenico Finocchiaro ,Mauro Iori

doi:10.15761/rdi.1000101

Abstract

Impact of a commercial 3D OSEM reconstruction algorithm on the 177Lu activity quantification of SPECT/CT imaging in a Molecular Radiotherapy trial

Highlights

In molecular radiotherapy (MRT) patients with disseminated or unresectable tumors are treated with radiopharmaceuticals that are designed to localize in cancer cells
Single photon emission computed tomography (SPECT) plays an important role in MRT of Neuroendocrine tumors (NET), since it is at present the main modality used to calculate a patient-specific dosimetry for an accurate and precise MRT planning, as pointed up by the joint European Association of Nuclear Medicine (EANM) / MIRD guidelines for quantitative 177Lu SPECT applied to MRT (MIRD Pamphlet No 26) [4]
In accordance with a recent guidance document issued by European Association of Nuclear Medicine (EANM) [29], the aim of the present study is to find out the optimum combination of the iterations and subsets employed in a commercial Ordered Subsets Expectation Maximization (OSEM) algorithm, in order to establish the quantitative accuracy of our clinical SPECT patient imaging studies

Summary

Introduction

In molecular radiotherapy (MRT) patients with disseminated or unresectable tumors are treated with radiopharmaceuticals that are designed to localize in cancer cells. This approach aims to deliver radiation to tumors, causing minimal toxicity to healthy organs. Neuroendocrine tumors (NET) expressing somatostatin receptors have currently been showing greatly increased incidence, making MRT with 177Lu-labelled somatostatin analogs a promising approach [1,2]. Single photon emission computed tomography (SPECT) plays an important role in MRT of NET, since it is at present the main modality used to calculate a patient-specific dosimetry for an accurate and precise MRT planning, as pointed up by the joint EANM / MIRD guidelines for quantitative 177Lu SPECT applied to MRT (MIRD Pamphlet No 26) [4]. An accurate personalized MRT planning is required

Objectives

Methods

Results

Discussion

Conclusion