**Neck Cyst** is a benign tumor or formation on the neck, which is a rounded lump filled with fluid, similar to a thin sphere. The cyst may be a solid formation and is called a fibrous cyst. It can appear in any part of the neck, but is most often located on the side of the neck. Cysts can be small or large and usually do not cause any symptoms for the patient, except in advanced cases with inflammation or suppuration of the cyst. Side ki