Quist (Cyst) és un sac tancat. Un quist (cyst) pot contenir aire, líquids o material semisòlid. Una col·lecció de pus s'anomena abscés, que no és un quist. Pot ser que s'hagi d'extirpar quirúrgicament el quist, però això dependrà del seu tipus i ubicació.
A cyst is a closed sac, having a distinct envelope and division compared with the nearby tissue. Hence, it is a cluster of cells that has grouped together to form a sac (like the manner in which water molecules group together to form a bubble); however, the distinguishing aspect of a cyst is that the cells forming the "shell" of such a sac are distinctly abnormal (in both appearance and behaviour) when compared with all surrounding cells for that given location. A cyst may contain air, fluids, or semi-solid material. A collection of pus is called an abscess, not a cyst. Once formed, a cyst may resolve on its own. When a cyst fails to resolve, it may need to be removed surgically, but that would depend upon its type and location.
Ganglion cyst ― Grumolls asimptomàtics que es produeixen de sobte entre les articulacions. Si es confirma el diagnòstic de quist ganglionar, el problema es pot resoldre prement el nòdul amb força per rebentar el quist a l'interior.
Mucocele ― Apareix com un cop suau als llavis sense cap símptoma.
