A ganglion cyst is a very common benign mass arising in the hand. These cysts are not cancerous. They usually arise near a joint or tendon in the hand and wrist. The most common location is the back of the wrist (dorsal carpal ganglion). They can occur in people of all ages and are common in young adults. The cause of a ganglion cyst is unknown in most cases. One theory proposes that the cyst arises from joint fluid which has leaked from a small opening in the joint capsule. The cyst is filled with a thick, jelly-like fluid and usually has a stalk which connects with a joint or tendon sheath. Many patients report that the cyst fluctuates in size, and in some cases the cyst can go away on its own. Treatment includes observation, aspiration, or surgical excision. Talk to your doctor if you would like to be evaluated for a ganglion cyst.
Watch video from American Society for Surgery of the Hand on ganglion cyst treatment