Immunohistochemical staining was conducted on the tumor sample for insulin (Klinipath MU029-UC, The Netherlands), CK18 (Cell Marque 760-4344, USA), and SSTR2A (Clinisciences NB-49-015, France); chromogranin A (Roche 760-2519, Switzerland); synaptophysin (Roche 790-4407); Ki-67 (Roche 790-4286); PDX1 (Abcam ab134150, USA); ARX (Millipore MABN102, Germany); ATRX (Sigma HPA001906, Germany); DAXX (Merck HPA008736, Germany); and menin (Bethyl Laboratories IHC-00572, USA). Here, MEN1 is linked to neoplasm.