I have a liver cyst , my doc is sending me to get a needle in to drain the cyst ? what is this

Fluid-filled cyst: Liver cysts are actually quite common and the vast majority are benign. If is is a simple cyst, which looks like a ball filled with fluid, it is usually not serious. There may be something about the character of the cyst or something in the rest of your medical history that is prompting your physician to feel it is best to study the fluid in the cyst. Discuss it further with the doc.

Infection or mass: The needle aspiration will be tested in lab and will determine if it is any infection or mass?