From Wikipedia for FEVERv2
Jump to navigation Jump to search

This article is about cysts in the body. Cyst_sentence_0

For the ICAO airport code CYST, see St. Cyst_sentence_1 Theresa Point Airport. Cyst_sentence_2

For hard-shelled resting stages of some small organisms, see Microbial cyst. Cyst_sentence_3


SpecialtyCyst_header_cell_0_1_0 Pathology, general surgeryCyst_cell_0_1_1

A cyst is a closed sac, having a distinct envelope and division compared with the nearby tissue. Cyst_sentence_4

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. Cyst_sentence_5

A cyst may contain air, fluids, or semi-solid material. Cyst_sentence_6

A collection of pus is called an abscess, not a cyst. Cyst_sentence_7

Once formed, a cyst may resolve on its own. Cyst_sentence_8

When a cyst fails to resolve, it may need to be removed surgically, but that would depend upon its type and location. Cyst_sentence_9

Cancer-related cysts are formed as a defense mechanism for the body following the development of mutations that lead to an uncontrolled cellular division. Cyst_sentence_10

Once that mutation has occurred, the affected cells divide incessantly and become cancerous, forming a tumour. Cyst_sentence_11

The body encapsulates those cells to try to prevent them from continuing their division and contain the tumour, which becomes known as a cyst. Cyst_sentence_12

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. Cyst_sentence_13

Once that happens, the capsule becomes useless, and the tumour may advance from benign to cancerous. Cyst_sentence_14

Some cysts are neoplastic, and thus are called cystic tumors. Cyst_sentence_15

Many types of cysts are not neoplastic; some are dysplastic or metaplastic. Cyst_sentence_16

Pseudocysts are similar to cysts in that they have a sac filled with fluid, but lack an epithelial lining. Cyst_sentence_17

Terminology Cyst_section_0


  • microcyst – a small cyst that requires magnification to be seenCyst_item_0_0
  • macrocyst – a cyst that is larger than usual or compared to othersCyst_item_0_1

Cysts by location Cyst_section_1

Female reproductive system Cyst_section_2


Scrotum Cyst_section_3


Cutaneous and subcutaneous Cyst_section_4


  • Cyst_item_3_14
    • Acne cyst – Pseudocysts associated with cystic acne - an inflammatory nodule with or without an associated epidermoid inclusion cystCyst_item_3_15
    • Arachnoid cyst (between the surface of the brain and the cranial base or on the arachnoid membrane)Cyst_item_3_16
    • Epidermoid cystCyst_item_3_17
    • Myxoid cyst (cutaneous condition often characterized by nail plate depression and grooves)Cyst_item_3_18
    • Pilar cyst (cyst of the scalp)Cyst_item_3_19
    • Pilonidal cyst (skin infection near tailbone)Cyst_item_3_20
    • Sebaceous cyst – sac below skinCyst_item_3_21
    • Trichilemmal cyst – same as a pilar cyst, a familial cyst of the scalpCyst_item_3_22

Head and neck Cyst_section_5


Chest Cyst_section_6


Abdomen Cyst_section_7


  • Cyst_item_6_35

Central nervous system Cyst_section_8


Musculoskeletal system Cyst_section_9


Seen in various locations Cyst_section_10


  • Dermoid cyst (seen in ovaries, testes, and many other locations, from head to tailbone)Cyst_item_9_53
  • Ganglion cyst (hand and foot joints and tendons)Cyst_item_9_54


  • Cyst_item_10_55
    • Mucoid cyst (ganglion cysts of the digits)Cyst_item_10_56

Infectious cysts Cyst_section_11


  • Cysticercal cyst – an infection due to the larval stage of Taenia sp. (Crain's backs)Cyst_item_11_57
  • Hydatid cyst – an infection in the liver or other parts of the body due to the larval stage of Echinococcus granulosus (tapeworm)Cyst_item_11_58

Neoplastic cysts Cyst_section_12


Treatment Cyst_section_13

Treatment ranges from simple enucleation of the cyst to curettage to resection. Cyst_sentence_18

There are cysts—e.g., buccal bifurcation cyst—that resolve on their own, in which just close observation may be employed, unless it is infected and symptomatic. Cyst_sentence_19

Related structures Cyst_section_14

A pseudocyst is very similar to a cyst, but is a collection of cells without a distinct membrane (epithelial or endothelial cells). Cyst_sentence_20

A syrinx in the spinal cord or brainstem is sometimes inaccurately referred to as a "cyst". Cyst_sentence_21

Cystic fibrosis Cyst_section_15

Despite being described in 1938 as "the microscopic appearance of cysts in the pancreas", cystic fibrosis is an example of a genetic disorder whose name is related to fibrosis of the cystic duct (which serves the gallbladder) and does not involve cysts. Cyst_sentence_22

This is just one example of how the Greek root cyst-, which simply means a fluid-filled sac, also is found in medical terms that relate to the urinary bladder and the gallbladder, neither of which involve cysts. Cyst_sentence_23

See also Cyst_section_16


Credits to the contents of this page go to the authors of the corresponding Wikipedia page: