The type of doctor who treats liver cysts is a gastroenterologist, according to the American College of Gastroenterology. These are doctors who specialize in diseases of the gastrointestinal tract, including the liver.
Gastroenterologists have a detailed knowledge of how a normal liver functions and how to diagnose and treat conditions such as liver cysts, the ACG notes.
To become a gastroenterologist, a medical student must complete a three-year residency in internal medicine. He then takes on a two- to three-year fellowship in gastroenterology. After that, a doctor who wishes to specialize in diseases of the liver might take another five years of specialty training.