The value of dosimetry in Peptide Receptor Radionuclide Therapy (PRRT) for neuroendocrine tumors: literature and practical aspects

PurposePeptide Receptor Radionuclide Therapy (PRRT) with radiolabeled somatostatin analogs has been demonstrated to be an effective treatment in patients with neuroendocrine tumors. Patient-specific dosimetry could improve the treatment, almost in terms of correlations between absorbed dose and tumor response or kidney/red marrow toxicity. However, this approach is not mostly applied in routine clinical practice. The aim of this expert review is to put in evidence to date the state of the art of dosimetry in PRRT therapy.MethodsFor this purpose, specific keywords (PRRT, dosimetry, dose-toxicity correlation, dose-response correlation, image-based dosimetry in different combinations) were employed in the Web of Science, Scopus and PUBMED databases. Scientific papers reporting the state-of-art of dosimetry and dose-effect outcomes in patients treated with PRRT were selected.Results62 papers were chosen in which dosimetric technical limitations, efficacy of dosimetry and dose/response-toxicity correlations were analysed.ConclusionDerived from the results in literature studies, a growing interest to patient-specific dosimetry is evident. Above all, prospective multicenter trials should be carried out to provide dose constraints derived from nuclear medicine therapy and not extrapolated from External Beam Radiotherapy (EBRT).