A ganglion cyst is a mass that can develop in various locations on the hand, most commonly on the back or the upper side of the wrist (dorsal wrist). Ganglion cysts are the most common form of growth on the hand. These cysts are most often harmless and are not cancerous masses. In fact, 95% of growths on the hand are discovered to be benign tumors, and 60% of this number is made up of ganglion cysts. These cysts are filled with fluids, and most often, they appear and disappear very quickly. #gan