Impact of intracellular radionuclide distribution in a Monte Carlo biophysical 3D multi‐cellular model for targeted alpha therapy.

Saved in:
Bibliographic Details
Title: Impact of intracellular radionuclide distribution in a Monte Carlo biophysical 3D multi‐cellular model for targeted alpha therapy.
Authors: Levrague, Victor1 (AUTHOR), Alcocer‐Ávila, Mario2 (AUTHOR), Otmani, Sarah Leilla1 (AUTHOR), Maigne, Lydia3 (AUTHOR), Testa, Etienne2 (AUTHOR), Beuve, Michaël2 (AUTHOR), Delorme, Rachel1 (AUTHOR) rachel.delorme@lpsc.in2p3.fr
Source: Medical Physics. Jul2025, Vol. 52 Issue 7, p1-16. 16p.
Subjects: Microdosimetry, Treatment effectiveness, Radioisotopes, Monte Carlo method, Radiotherapy, Cell survival
Abstract: Background: To understand and predict the therapeutic efficacy of targeted alpha therapy (TAT), nano‐ and microdosimetry are needed to consider the very heterogeneous dose deposition at cellular and subcellular levels. Purpose: The objective of this study is to theoretically evaluate the importance of cell internalization of alpha‐emitters on relevant dosimetric and biological endpoints. Methods: Isolated cells and realistic 3D multi‐cellular geometries (spheroids modeled with CPOP) were generated as well as distributions of alpha‐emitters corresponding to various cellular internalization cases. The alpha particles emitted were tracked with Geant4 (Monte Carlo) simulations. We calculated mean specific energies deposited into each cell nucleus (Zn$Z_n$), cell survival fractions using the NanOx biophysical model, values of relative biological effectiveness (RBE) and tumor control probabilities (TCP) for each scenarios. The impact of spheroid compaction and size, alpha particle energy and radionuclide daughter diffusion was studied. The impact of the heterogeneous distribution of a number of alpha particles per cell was also studied, using a lognormal probability law. Results: For a given activity per cell (APC), the radionuclide distribution had a critical influence on Zn$Z_n$ in isolated cancerous cells or small spheroids (<$<$50 μm$\mu{\rm m}$ radius), while its impact was relatively low in larger and more compact spheroids, with a maximum variation of 30% between the distributions. For an average 10% cell survival, RBE was found to be approximately between 2.3 and 3.3, depending on the spatial radionuclide distribution and the activity distribution per cell. TCP of 1 was always obtained with an APC larger than 0.534 mBq when a uniform tumoral distribution of radionuclides was considered, and for APC larger than 0.801 mBq with a lognormal distribution. However, below these activities, TCP could strongly depend on the radionuclide distributions up to a factor of 9.5 with a uniform distribution and 1.5 for a lognormal one. Conclusions: According to these findings, a precise modeling of alpha‐emitter intracellular distributions may be required for small micro‐metastases or tumors presenting regions with relatively low radionuclide concentration in order to limit the prediction uncertainties on biological outputs. Intratumoral fluctuations of APC were also found to be a critical parameter to consider for therapeutic efficacy prediction in TAT. [ABSTRACT FROM AUTHOR]
Copyright of Medical Physics is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
Full text is not displayed to guests.
FullText Links:
  – Type: pdflink
Text:
  Availability: 1
Header DbId: egs
DbLabel: Engineering Source
An: 186809934
AccessLevel: 6
PubType: Academic Journal
PubTypeId: academicJournal
PreciseRelevancyScore: 0
IllustrationInfo
Items – Name: Title
  Label: Title
  Group: Ti
  Data: Impact of intracellular radionuclide distribution in a Monte Carlo biophysical 3D multi‐cellular model for targeted alpha therapy.
– Name: Author
  Label: Authors
  Group: Au
  Data: &lt;searchLink fieldCode=&quot;AR&quot; term=&quot;%22Levrague%2C+Victor%22&quot;&gt;Levrague, Victor&lt;/searchLink&gt;&lt;relatesTo&gt;1&lt;/relatesTo&gt; (AUTHOR)&lt;br /&gt;&lt;searchLink fieldCode=&quot;AR&quot; term=&quot;%22Alcocer‐&#193;vila%2C+Mario%22&quot;&gt;Alcocer‐&#193;vila, Mario&lt;/searchLink&gt;&lt;relatesTo&gt;2&lt;/relatesTo&gt; (AUTHOR)&lt;br /&gt;&lt;searchLink fieldCode=&quot;AR&quot; term=&quot;%22Otmani%2C+Sarah+Leilla%22&quot;&gt;Otmani, Sarah Leilla&lt;/searchLink&gt;&lt;relatesTo&gt;1&lt;/relatesTo&gt; (AUTHOR)&lt;br /&gt;&lt;searchLink fieldCode=&quot;AR&quot; term=&quot;%22Maigne%2C+Lydia%22&quot;&gt;Maigne, Lydia&lt;/searchLink&gt;&lt;relatesTo&gt;3&lt;/relatesTo&gt; (AUTHOR)&lt;br /&gt;&lt;searchLink fieldCode=&quot;AR&quot; term=&quot;%22Testa%2C+Etienne%22&quot;&gt;Testa, Etienne&lt;/searchLink&gt;&lt;relatesTo&gt;2&lt;/relatesTo&gt; (AUTHOR)&lt;br /&gt;&lt;searchLink fieldCode=&quot;AR&quot; term=&quot;%22Beuve%2C+Micha&#235;l%22&quot;&gt;Beuve, Micha&#235;l&lt;/searchLink&gt;&lt;relatesTo&gt;2&lt;/relatesTo&gt; (AUTHOR)&lt;br /&gt;&lt;searchLink fieldCode=&quot;AR&quot; term=&quot;%22Delorme%2C+Rachel%22&quot;&gt;Delorme, Rachel&lt;/searchLink&gt;&lt;relatesTo&gt;1&lt;/relatesTo&gt; (AUTHOR)&lt;i&gt; rachel.delorme@lpsc.in2p3.fr&lt;/i&gt;
– Name: TitleSource
  Label: Source
  Group: Src
  Data: &lt;searchLink fieldCode=&quot;JN&quot; term=&quot;%22Medical+Physics%22&quot;&gt;Medical Physics&lt;/searchLink&gt;. Jul2025, Vol. 52 Issue 7, p1-16. 16p.
– Name: Subject
  Label: Subjects
  Group: Su
  Data: &lt;searchLink fieldCode=&quot;DE&quot; term=&quot;%22Microdosimetry%22&quot;&gt;Microdosimetry&lt;/searchLink&gt;&lt;br /&gt;&lt;searchLink fieldCode=&quot;DE&quot; term=&quot;%22Treatment+effectiveness%22&quot;&gt;Treatment effectiveness&lt;/searchLink&gt;&lt;br /&gt;&lt;searchLink fieldCode=&quot;DE&quot; term=&quot;%22Radioisotopes%22&quot;&gt;Radioisotopes&lt;/searchLink&gt;&lt;br /&gt;&lt;searchLink fieldCode=&quot;DE&quot; term=&quot;%22Monte+Carlo+method%22&quot;&gt;Monte Carlo method&lt;/searchLink&gt;&lt;br /&gt;&lt;searchLink fieldCode=&quot;DE&quot; term=&quot;%22Radiotherapy%22&quot;&gt;Radiotherapy&lt;/searchLink&gt;&lt;br /&gt;&lt;searchLink fieldCode=&quot;DE&quot; term=&quot;%22Cell+survival%22&quot;&gt;Cell survival&lt;/searchLink&gt;
– Name: Abstract
  Label: Abstract
  Group: Ab
  Data: Background: To understand and predict the therapeutic efficacy of targeted alpha therapy (TAT), nano‐ and microdosimetry are needed to consider the very heterogeneous dose deposition at cellular and subcellular levels. Purpose: The objective of this study is to theoretically evaluate the importance of cell internalization of alpha‐emitters on relevant dosimetric and biological endpoints. Methods: Isolated cells and realistic 3D multi‐cellular geometries (spheroids modeled with CPOP) were generated as well as distributions of alpha‐emitters corresponding to various cellular internalization cases. The alpha particles emitted were tracked with Geant4 (Monte Carlo) simulations. We calculated mean specific energies deposited into each cell nucleus (Zn$Z_n$), cell survival fractions using the NanOx biophysical model, values of relative biological effectiveness (RBE) and tumor control probabilities (TCP) for each scenarios. The impact of spheroid compaction and size, alpha particle energy and radionuclide daughter diffusion was studied. The impact of the heterogeneous distribution of a number of alpha particles per cell was also studied, using a lognormal probability law. Results: For a given activity per cell (APC), the radionuclide distribution had a critical influence on Zn$Z_n$ in isolated cancerous cells or small spheroids (&lt;$&lt;$50 μm$\mu{\rm m}$ radius), while its impact was relatively low in larger and more compact spheroids, with a maximum variation of 30% between the distributions. For an average 10% cell survival, RBE was found to be approximately between 2.3 and 3.3, depending on the spatial radionuclide distribution and the activity distribution per cell. TCP of 1 was always obtained with an APC larger than 0.534 mBq when a uniform tumoral distribution of radionuclides was considered, and for APC larger than 0.801 mBq with a lognormal distribution. However, below these activities, TCP could strongly depend on the radionuclide distributions up to a factor of 9.5 with a uniform distribution and 1.5 for a lognormal one. Conclusions: According to these findings, a precise modeling of alpha‐emitter intracellular distributions may be required for small micro‐metastases or tumors presenting regions with relatively low radionuclide concentration in order to limit the prediction uncertainties on biological outputs. Intratumoral fluctuations of APC were also found to be a critical parameter to consider for therapeutic efficacy prediction in TAT. [ABSTRACT FROM AUTHOR]
– Name: AbstractSuppliedCopyright
  Label:
  Group: Ab
  Data: &lt;i&gt;Copyright of Medical Physics is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites without the copyright holder&#39;s express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract.&lt;/i&gt; (Copyright applies to all Abstracts.)
PLink https://search.ebscohost.com/login.aspx?direct=true&site=eds-live&db=egs&AN=186809934
RecordInfo BibRecord:
  BibEntity:
    Identifiers:
      – Type: doi
        Value: 10.1002/mp.17917
    Languages:
      – Code: eng
        Text: English
    PhysicalDescription:
      Pagination:
        PageCount: 16
        StartPage: 1
    Subjects:
      – SubjectFull: Microdosimetry
        Type: general
      – SubjectFull: Treatment effectiveness
        Type: general
      – SubjectFull: Radioisotopes
        Type: general
      – SubjectFull: Monte Carlo method
        Type: general
      – SubjectFull: Radiotherapy
        Type: general
      – SubjectFull: Cell survival
        Type: general
    Titles:
      – TitleFull: Impact of intracellular radionuclide distribution in a Monte Carlo biophysical 3D multi‐cellular model for targeted alpha therapy.
        Type: main
  BibRelationships:
    HasContributorRelationships:
      – PersonEntity:
          Name:
            NameFull: Levrague, Victor
      – PersonEntity:
          Name:
            NameFull: Alcocer‐Ávila, Mario
      – PersonEntity:
          Name:
            NameFull: Otmani, Sarah Leilla
      – PersonEntity:
          Name:
            NameFull: Maigne, Lydia
      – PersonEntity:
          Name:
            NameFull: Testa, Etienne
      – PersonEntity:
          Name:
            NameFull: Beuve, Michaël
      – PersonEntity:
          Name:
            NameFull: Delorme, Rachel
    IsPartOfRelationships:
      – BibEntity:
          Dates:
            – D: 01
              M: 07
              Text: Jul2025
              Type: published
              Y: 2025
          Identifiers:
            – Type: issn-print
              Value: 00942405
          Numbering:
            – Type: volume
              Value: 52
            – Type: issue
              Value: 7
          Titles:
            – TitleFull: Medical Physics
              Type: main
ResultId 1