Branchial cleft cyst explained

Branchial cyst
Synonyms:Branchial arch fistula
Benign cervical lymphoepithelial cyst
Pharyngeal arch cyst
Symptoms:Painless, firm mass lateral to midline, usually anterior to the SCM, which does not move with swallowing
Causes:Family history
Differential:Vascular anomaly, dermoid cyst, thymic cyst, lymphadenopathy, lymphoma, HPV-related oropharyngeal cancer
Treatment:Conservative, surgical excision

A branchial cleft cyst or simply branchial cyst is a cyst as a swelling in the upper part of neck anterior to sternocleidomastoid. It can, but does not necessarily, have an opening to the skin surface, called a fistula. The cause is usually a developmental abnormality arising in the early prenatal period, typically failure of obliteration of the second, third, and fourth branchial cleft, i.e. failure of fusion of the second branchial arches and epicardial ridge in lower part of the neck. Branchial cleft cysts account for almost 20% of neck masses in children.[1] Less commonly, the cysts can develop from the first, third, or fourth clefts, and their location and the location of associated fistulas differs accordingly.

Symptoms and signs

Most branchial cleft cysts present in late childhood or early adulthood as a solitary, painless mass, which went previously unnoticed, that has now become infected (typically after an upper respiratory tract infection). Fistulas, if present, are asymptomatic until infection arises.[2]

Pathophysiology

Branchial cleft cysts are remnants of embryonic development and result from a failure of obliteration of one of the branchial clefts, which are homologous to the structures in fish that develop into gills.[3] [4]

Pathology

The cyst wall is composed of squamous epithelium (90%), columnar cells with or without cilia, or a mixture of both, with lymphoid infiltrate, often with prominent germinal centers and few subcapsular lymph sinuses. The cyst is typically surrounded by lymphoid tissue that has attenuated or absent overlying epithelium due to inflammatory changes.[5]

Diagnosis

The diagnosis of branchial cleft cysts is typically done clinically due to their relatively consistent location in the neck, typically anterior to the sternocleidomastoid muscle. For masses presenting in adulthood, the presumption should be a malignancy until proven otherwise, since carcinomas of the tonsil, tongue base and thyroid may all present as cystic masses of the neck.[6] Unlike a thyroglossal duct cyst, when swallowing, the mass should not move up or down.[7]

Types

Four branchial clefts (also called "grooves") form during the development of a human embryo. The first cleft normally develops into the external auditory canal,[8] but the remaining three arches are obliterated and have no persistent structures in normal development. Persistence or abnormal formation of these four clefts can all result in branchial cleft cysts which may or may not drain via sinus tracts.

Treatment

Conservative (i.e. no treatment), or surgical excision. With surgical excision, recurrence is common, usually due to incomplete excision. Often, the tracts of the cyst will pass near important structures, such as the internal jugular vein, carotid artery, or facial nerve, making complete excision impractical due to the high risk of complications.[11]

An alternative and less invasive treatment is ultrasound-guided sclerotherapy.[12]

See also

External links

Notes and References

  1. Pincus RL . 2001. Congenital neck masses and cysts. Head & Neck Surgery - Otolaryngology. 3. Lippincott Williams & Wilkins. 933.
  2. Book: Colman, Rebecca . Toronto Notes. vanc . 2008. OT33.
  3. Web site: Hong . Chih-ho . vanc . Branchial cleft cyst . eMedicine.com . 24 August 2008 .
  4. Book: Shubin . Neil . vanc . Your Inner Fish . 2009 . Vintage . 978-0-307-27745-9.
  5. Nahata V . Branchial Cleft Cyst . Indian Journal of Dermatology . 61 . 6 . 701 . 2016 . 27904209 . 5122306 . 10.4103/0019-5154.193718 . free .
  6. Web site: Differential diagnosis of a neck mass. www.uptodate.com. UpToDate. 2018-08-18.
  7. Web site: Branchial Cleft Cyst. missinglink.ucsf.edu. 2019-06-26. 2019-06-26. https://web.archive.org/web/20190626210813/http://missinglink.ucsf.edu/restricted/lm/CongenitalAnomalies/BranchialCleftCyst.html. dead.
  8. Web site: Duke Embryology - Craniofacial Development. web.duke.edu. 2016-09-08.
  9. Quintanilla-Dieck . Lourdes . Penn . Edward B. . December 2018 . Congenital Neck Masses . Clinics in Perinatology . en . 45 . 4 . 769–785 . 10.1016/j.clp.2018.07.012. 30396417 . 53224066 .
  10. Koch . BL . Cystic malformations of the neck in children. . Pediatric radiology . May 2005 . 35 . 5 . 463-77 . 10.1007/s00247-004-1388-0 . 15785931.
  11. Waldhausen JH . Branchial cleft and arch anomalies in children . Seminars in Pediatric Surgery . 15 . 2 . 64–9 . May 2006 . 16616308 . 10.1053/j.sempedsurg.2006.02.002 .
  12. Kim J . Ultrasound-guided sclerotherapy for benign non-thyroid cystic mass in the neck . Ultrasonography . 33 . 2 . 83–90 . April 2014 . 24936500 . 10.14366/usg.13026 . 4058977 . free .