Cystic teratomas and dermoid cysts – ovarian
A dermoid cyst in the ovary is a sac-like growth that contains hair, fat, and other tissue. A dermoid cyst might include clumps of long hair, blood, bone, teeth, nails, eyes, cartilage and thyroid tissue.
As terrifying as that sounds, these ovarian cysts can appear anywhere on the body and are classified slightly differently by several disciplines.
A dermoid cyst may be classified as a cystic teratoma, a rare tumour. A cystic teratoma is a thick, leathery capsule covering fatty tissue. A malignant melanoma may occur in a cystic teratoma.
The mature cystic teratoma (MCT) or dermoid cysts are the most common benign masses found in adolescents.
What is a cystic teratoma/dermoid cyst?
The dermoid cyst is a benign germ cell tumour.​1​ A germ cell is a cell that contains half the chromosomes of a full cell, that is able to combine with the other half and form a new person: a gamete. Except, it only has one half of the puzzle.
These tumours arise from totipotent cells in the ovary. A totipotent cell is an immature or stem cell that can turn into any type of cell. That’s why the tumour could contain hair, teeth or nails, or any other tissue in the body. ​2​
Dermoid cysts account for around 70 per cent of benign ovarian tumours in those under age 30, and half of all children’s tumours. It’s unclear just how often these tumours are appearing, since most of the time they are only discovered accidentally, during other imaging.
Symptoms of cystic teratomas/dermoid cysts
MCTs are usually without symptoms, but if symptoms are present, they are typically:
- Abdominal pain
- Increased abdominal girth
- Palpable abdominal mass
- Constipation
- Nausea
- Vomiting
- Loss of appetite
Why do cystic teratomas and dermoid cysts grow?
It’s unclear why dermoid cysts develop, but one suggestion has been increasing oestrogen and progesterone stimulate the sebaceous gland component of the tumour. This can, in part, explain the size increases – with a growth rate of 1.8mm per year – after puberty and the halt in growth after menopause.
In 10-20 per cent of cases, cystic teratoma tumours are on both ovaries.​3​
Immature teratomas account for less than one per cent of ovarian teratomas and are composed of all three germ cell layers. But, unlike MCTs, the cells are haphazard and not fully differentiated.
References​4,5​
- 1.Deguchy Q Jr, Fananapazir G, Corwin M, Lamba R, Gerscovich E, McGahan J. Benign Rapidly Growing Ovarian Dermoid Cysts. Journal of Diagnostic Medical Sonography. Published online August 20, 2016:71-74. doi:10.1177/8756479316664313
- 2.Sahin H, Abdullazade S, Sanci M. Mature cystic teratoma of the ovary: a cutting edge overview on imaging features. Insights Imaging. Published online January 19, 2017:227-241. doi:10.1007/s13244-016-0539-9
- 3.Pepe F, Lo M, Rapisarda F, Raciti G, Genovese C, Pepe P. An unusual case of multiple and bilateral ovarian dermoid cysts. Case report. G Chir. 2014;35(3-4):75-77. https://www.ncbi.nlm.nih.gov/pubmed/24841683
- 4.Sinha A, Ewies AAA. Ovarian Mature Cystic Teratoma: Challenges of Surgical Management. Obstetrics and Gynecology International. Published online 2016:1-7. doi:10.1155/2016/2390178
- 5.O’Neill KE, Cooper AR. The Approach to Ovarian Dermoids in Adolescents and Young Women. Journal of Pediatric and Adolescent Gynecology. Published online June 2011:176-180. doi:10.1016/j.jpag.2010.11.006
