Because the diagnosis is established and it is known that 80–95% of gastrinomas in ZES/MEN1 patients occur in the duodenum, which are small in size, associated with lymph node metastases in (40–60%) [2,288,477,480,484,493] and the conventional imaging studies frequently miss most pNETs < 1.5–2 cm and some >1.5–2 cm [54,226,291], guidelines also recommend that a 68Ga-DOTATATE PET/CT scan also be performed [18,54,226,326]. The gene discussed is MEN1; the disease is gastrin-producing neuroendocrine tumor.