Combination treatments to enhance peptide receptor radionuclide therapy of neuroendocrine tumours

  • Samuel Adant
  • Girish M. ShahEmail author
  • Jean-Mathieu BeauregardEmail author
Review Article
Part of the following topical collections:
  1. Oncology – General


The incidence of neuroendocrine tumours (NETs) is increasing, but curative therapeutic options are limited because diagnosis is often delayed until the tumour has metastasized. Peptide receptor radionuclide therapy (PRRT) is among the most effective therapeutic options for metastatic NETs because of targeted delivery of radioactivity to the tumour via the somatostatin receptor (SSTR) and relatively low systemic toxicity. However, current PRRT regimes result in palliation rather than cure, and higher doses of PRRT that might achieve remission would also be too toxic to the patients. Therefore, there is a need to improve PRRT of NETs by combining it with other agents to achieve maximum benefits from the internal radiation therapy, while sparing non-target organs from radiation toxicity. Here we review various current and potential combination strategies to improve 177Lu-octreotate-based PRRT of NET, some of which could also apply to other radionuclide therapies. These strategies include co-administered drugs that improve delivery of the radiopharmaceutical via increased tumour perfusion or through increased SSTR density at tumour surface. Other combinations are aimed at enhancing the biological effects of the radiation-induced DNA damage in tumour cells or generating additional DNA damage burden to effectively increase the cytotoxicity of PRRT. We also propose an algorithm for stratifying NET patients to receive or not combination therapies with PRRT. Considering that PRRT and many of these combination agents are already used for treating patients with NET and other cancers, the proposed strategies to improve the efficacy of PRRT could be rapidly translated into the clinic.


Neuroendocrine tumours Peptide receptor radionuclide therapy 177Lu-octreotate 177Lu-DOTATATE Somatostatin receptor Radiosensitization Receptor upregulation Tumour perfusion DNA damage 



We would like to thank Marine A. Merlin for helpful discussion to improve the manuscript.


This work was supported by research funding to J.M.B. and G.M.S. from the Canadian Cancer Society Research Institute (grant no. 705327) and the Carcinoid-NeuroEndocrine Tumor Society of Canada,; and to J.M.B. from the Education and Research Foundation for Nuclear Medicine and Molecular Imaging, Quebec Bio-Imaging Network, Fondation du CHU de Québec – Université Laval and Fonds de Recherche du Québec – Santé. S.A. received a scholarship from the Canadian Institutes of Health Research.

Compliance with ethical standards

Conflict of interest

The authors declare they have no conflict of interest related to this work. J.M.B. has received honoraria for invited conferences from Ipsen, Novartis, and Siemens Healthineers.

Ethical approval

Not applicable. This article does not contain any studies with human participants or animals performed by any of the authors other than those previously published and cited in this review article.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Radiology and Nuclear Medicine and Cancer Research CentreUniversité LavalQuebec CityCanada
  2. 2.Department of Medical Imaging and Oncology Division of Research CentreCHU de Québec – Université LavalQuebec CityCanada
  3. 3.Department of Molecular Biology, Medical Biochemistry and Pathology and Cancer Research CentreUniversité LavalQuebec CityCanada
  4. 4.Neurosciences and Oncology Divisions of CHU de Québec – Université Laval Research CentreQuebec CityCanada

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