Regular Article

Management of patients receiving radionuclide therapy with unsealed radionuclides: a proposed approach to the definition of release criteria in Italy

¹ Medical Physics Section, ASL Roma 6, Borgo Garibaldi, 12, 00041, Rome, Italy
² ENEA, Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Lungotevere Thaon di Revel 76, 00196, Rome, Italy
³ Fondazione Policlinico Universitario A. Gemelli IRCSS, L. go Agostino Gemelli, 8, 00168, Rome, Italy

^a marco.darienzo@aslroma6.it

Received: 15 February 2021
Accepted: 4 July 2021
Published online: 20 October 2021

Abstract

The decision to release a patient receiving medical treatments with unsealed radionuclides should take many factors into account, and is the balance among different requirements. The Italian legislative implementation of the new European Commission Basic Safety Standards (BSS) resulted in the recent Legislative Decree 101/2020, which sets specific dose constraints for the public and for carers and comforters. The aim of the present research is to assess acceptable release criteria (in terms of personal dose-equivalent rate at the moment of hospital discharge) to ensure compliance with the current regulatory framework in Italy. The MicroShield^® code was used to derive a more realistic model for the emission of radioactivity by patients treated with radiopharmaceuticals. A geometric source-dependent correction factor, G(r), is introduced in order to take into account the volumetric distribution of the radionuclide into the human body and the attenuation of radiation from body tissues. The proposed approach has the potential to be routinely applied by clinic decision-makers to assess release criteria in the nuclear medicine practice.