Pancreatic NETs are typically seen as hyperattenuating masses on arterial and portal venous phase CT images because of their rich blood supply. 

Cystic pancreatic NET is considered uncommon and often is a component of a large tumor with cystic degeneration or necrosis. 

However, small NETs with a cystic change are occasionally encountered on CT. Cystic pancreatic NETs can mimic other cystic pancreatic masses on imaging studies.