AFP and diabetes mellitus: Abbreviations:NETs – neuroendocrine tumors, NEC – neuroendocrine carcinoma, CT – computed tomography, MRI – magnetic resonance imaging, DM – diabetes mellitus, WHO – World Health Organisation, HCV – hepatitis C virus, CEA – carcinoembryonic antigen, AFP – alpha-fetoprotein, 5-HIAA – 5-Hydroxyindoleacetic acid, IHC – immunohistochemistry, EUS – endoscopic ultrasonography, EUS FNA – endoscopic ultrasonography with fine needle aspiration, CgA – chromogranin A, PRRT – peptide receptor radioligand therapy