Likewise, the fact that all glucagonomas in this series were large and clinically aggressive, showed ATRX/DAXX mutations in 4/6 cases, and showed unexpected co-expression of non-alpha-cell marker PDX1 in 5/6 cases strongly suggests (epi)genetic similarities with non-functional PanNETs as well as with aggressive insulinomas [8]. The gene discussed is PDX1; the disease is pancreatic insulinoma.