A ganglion cyst is a noncancerous lump filled with a jelly-like fluid and can appear on the foot. Learn more about the symptoms, causes, and treatment options.

A ganglion cyst is a round, fluid-filled lump of tissue that appears along tendons or joints. Learn more about causes, symptoms, and treatment.

The exact causes of cysts are unknown. Some arise when hair follicles become clogged, trapping in the skin cells. Penetrating injury—such as a body piercing—can also cause cysts to form, as ...