Ganglion cysts are usually harmless and noncancerous, but they can become painful and interfere with joint movement if they press on a nerve. Generally, if the cyst is small and not causing any problems, it does not need to be treated. However, if it is large and painful, you should see a doctor to discuss treatment options. A doctor may suggest aspiration (removing the fluid with a needle), surgery, or they may recommend keeping an eye on it to see if it gets worse. Make sure to see a doctor if the cyst changes in size, becomes painful, or if it interferes with movement.