Cyst

A cyst/sɪst/ is a closed sac in the body, having a distinct envelope and division compared with the nearby tissue. Hence, it is a cluster of cells that have 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. Otherwise, it may need to be removed surgically, depending upon its type and location.

Cancer-related cysts are formed as a defense mechanism for the body following the development of mutations that lead to an uncontrolled cellular division. Once such a mutation has occurred, the affected cells divide incessantly and become cancerous, forming a tumor. The body encapsulates those cells to try to prevent them from continuing their division and contain the tumor, which becomes known as a cyst. That said, the cancerous cells still may mutate further and gain the ability to form their own blood vessels, from which they receive nourishment before being contained. Once that happens, the capsule becomes useless, and the tumor may advance from benign to cancerous.

Some cysts are neoplastic, and thus are called cystic tumors. Many types of cysts are not neoplastic but are dysplastic or metaplastic. Pseudocysts are similar to cysts in that they have a sac filled with fluid, but lack an epithelial lining.

• microcyst – a small cyst that requires magnification to be seen
• macrocyst – a cyst that is larger than usual or compared to others

A pseudocyst is very similar to a cyst, but is a collection of cells without a distinct membrane (epithelial or endothelial cells).

A veces, una siringe en la médula espinal o el tronco encefálico se denomina erróneamente "quiste".

• Quiste cisticercal : una infección causada por la fase larvaria de Taenia sp. (espalda de craneía).
• Quiste hidatídico : una infección en el hígado u otras partes del cuerpo causada por la fase larvaria de Echinococcus granulosus ( tenia ).

• quiste dermoide
• Tumor odontogénico queratoquístico
• quiste odontogénico calcificante

El tratamiento abarca desde la simple enucleación del quiste hasta el curetaje y la resección . Existen quistes —por ejemplo, el quiste de bifurcación bucal— que se resuelven espontáneamente, en cuyo caso basta con una observación minuciosa, a menos que estén infectados y presenten síntomas . ^{[ 15 ]}

A pesar de haber sido descrita en 1938 como "la apariencia microscópica de quistes en el páncreas", ^{[ 16 ]} la fibrosis quística es un ejemplo de un trastorno genético cuyo nombre está relacionado con la fibrosis del conducto cístico (que irriga la vesícula biliar ) y no implica quistes. ^{[ 17 ]}

Este es solo un ejemplo de cómo la raíz griega cyst- , que simplemente significa saco lleno de líquido, también se encuentra en términos médicos relacionados con la vejiga urinaria y la vesícula biliar , ninguna de las cuales presenta quistes.

• Lista de afecciones cutáneas
• Contra un Wen

• Stöppler, Melissa Conrad. "¿Qué es un quiste? Tipos, síntomas, signos y causas" . MedicineNet .
• De Maio, Fernando; Di Marcantonio, Arianna; De Luna, Vincenzo; Caterini, Alessandro; Tresoldi, Ilaria; Farsetti, Pasquale (2020). "Quiste sinovial de la articulación acromioclavicular con y sin rotura del manguito rotador: Serie de casos de dos pacientes" . International Journal of Surgery Case Reports . 75 : 390–393 . doi : 10.1016/j.ijscr.2020.09.084 . PMC 7522442. PMID 32992095 .