International Survey for the Use of Biomarkers and Molecular Imaging in Neuroendocrine Tumors (NET): What we are Using in Daily Practice.

Introduction: Several guidelines have given recommendations for optimal use of biomarkers and molecular imaging. However, those guidelines' implementation may not be always possible due to local policies or lack of access to several diagnostic studies. Aim(s): To identify which biomarkers and molecular imaging are used in daily practice. Materials and methods: Seventy-two NET centers (68%: European) completed a web-based survey, based on 14 questions, regarding: a) local availability of biomarkers and molecular imaging studies; b) choice of the appropriate diagnostic modalities for different types of NET; and c) follow-up intervals. Results: Common biomarkers, as well as OctreoScan and 16F-FGD-PET scan, are available to the majority. Only 18% have access to DOPA or 68Ga PETs. Ten percent and 9% would never perform or perform OctreoScan only in selected patients, respectively, at diagnosis. Nine percent would perform routinely FGD-PET at diagnosis. Almost all are using Chromogranin-A for all NET and 45% are using NSE for midgut and hindgut NET. Thirty-eight percent and 55% are using urine 5-HIAA levels, in pancreatic and hindgut NET, respectively. The majority would perform functional imaging routinely during follow-up. Follow-up intervals depend on tumor histology, according to the majority. Conclusion: The availability of new molecular imaging studies is still limited. Some biomarkers and molecular imaging studies are used sub-optimally. Most centers are following ENETS Guidelines with regards to follow-up intervals. [ABSTRACT FROM AUTHOR]