The Challenge of Evaluating Response to Peptide Receptor Radionuclide Therapy in Gastroenteropancreatic Neuroendocrine Tumors: The Present and the Future

Virginia Liberini; Martin W Huellner; Serena Grimaldi; Monica Finessi; Philippe Thuillier; Alfredo Muni; Riccardo E Pellerito; Mauro G Papotti; Alessandro Piovesan; Emanuela Arvat; Désirée Deandreis

doi:10.3390/diagnostics10121083

The Challenge of Evaluating Response to Peptide Receptor Radionuclide Therapy in Gastroenteropancreatic Neuroendocrine Tumors: The Present and the Future

Diagnostics (Basel). 2020 Dec 12;10(12):1083. doi: 10.3390/diagnostics10121083.

Authors

Affiliations

¹ Nuclear Medicine Unit, Department of Medical Sciences, University of Turin, 10126 Turin, Italy.
² Department of Nuclear Medicine, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland.
³ Department of Endocrinology, University Hospital of Brest, 29200 Brest, France.
⁴ Department of Nuclear Medicine, S.S. Biagio e Antonio e C. Arrigo Hospital, 15121 Alessandria, Italy.
⁵ Department of Nuclear Medicine, AO Ordine Mauriziano di Torino, 10128 Turin, Italy.
⁶ Pathology Unit, City of Health and Science University Hospital, 10126 Turin, Italy.
⁷ Department of Oncology, University of Turin at Molinette Hospital, 10126 Turin, Italy.
⁸ Department of Endocrinology, A. O. U. Città della Salute della Scienza of Turin, 10126 Turin, Italy.
⁹ Oncological Endocrinology, Department of Medical Sciences, University of Turin, 10126 Turin, Italy.

Abstract

The NETTER-1 study has proven peptide receptor radionuclide therapy (PRRT) to be one of the most effective therapeutic options for metastatic neuroendocrine tumors (NETs), improving progression-free survival and overall survival. However, PRRT response assessment is challenging and no consensus on methods and timing has yet been reached among experts in the field. This issue is owed to the suboptimal sensitivity and specificity of clinical biomarkers, limitations of morphological response criteria in slowly growing tumors and necrotic changes after therapy, a lack of standardized parameters and timing of functional imaging and the heterogeneity of PRRT protocols in the literature. The aim of this article is to review the most relevant current approaches for PRRT efficacy prediction and response assessment criteria in order to provide an overview of suitable tools for safe and efficacious PRRT.

Keywords: 18F-FDG; 68Ga-labeled somatostatin analogue; NET; PRRT; RECIST; SWOG; WHO; neuroendocrine tumors; peptide receptor radionuclide therapy; response assessment.

Publication types

Review