A ganglion is a small cyst (fluid-filled sac) located next to a joint or tendon. It is most often found near the wrist joint or finger. A ganglion may cause pain if it is putting pressure against a tendon or joint. In most cases, these lesions are benign (not cancer) but require medical evaluation. Evaluation is needed to determine if it is a cyst.

Treatment includes observation or removal of the cyst.