Value of somatostatin receptor PET/CT in MEN1 patients at various stages of their disease

J Clin Endocrinol Metab. 2021 Dec 23;dgab891. doi: 10.1210/clinem/dgab891. Online ahead of print.

Abstract

Context: Despite the growing evidence of the clinical value of somatostatin receptor (SSTR) PET in the evaluation of neuroendocrine tumors/NET, its role remains to be clarified at different time points in the MEN1 patient journey. The rareness of the disease is however a significant impediment to prospective clinical trials.

Objectives: The goals of the study were to assess the indications and value of SSTR PET/CT in MEN1 patients.

Methods: We retrospectively included patients from 7 French expert centres for whom data on SSTR PET/CT and morphological imaging performed at the same period were available. Detection rates of PET study were analysed.

Results: One hundred eight patients were included. SSTR PET/CT was performed at screening (n=33), staging (n=34), restaging (n=37) and for PRRT selection (n=4). PET detected positive pancreatic lesions in 91% of cases at screening, with comparable results to MRI but superiority to CT (P=0.049). Metastases (mostly LN) were present at the screening phase in 28% of cases, possibly due to the suboptimal value of screening morphological imaging in the assessement of nodal metastases and/or a long delay between imaging studies. SSTR PET/CT was considered as superior or complementary to the reference standard in the assessment of LN or distant metastases in the vast majority of cases and regardless of the clinical scenario.

Conclusion: This study shows the potential added value of SSTR PET in the assessment of MEN1-associated NETs and provides a great impetus towards its implementation in the evaluation of MEN1 patients.

Keywords: Gallium-68 labeled somatostatin analogs; MEN1; Positron emission tomography; genetics; neuroendocrine tumors; somatostatin receptors.