The twin within (3) A dermoid cyst

There is a fair amount of controversy about dermoid cysts.  On the one hand it seems like a fairly normal anomaly of the skin cells, which forms a cyst under the skin, but on the other a dermoid cyst may develop far away from the skin, deep inside the body on an ovary or in the abdomen.

Typically, a dermoid cyst contains structures that are related to the outer layers of the body ( fat, hair, teeth.)

They can be any size, and may grow as large as a grapefruit. Here is a picture. ( after surgical excision)

It seems an extraordinary idea to call such an object an "enclosed monozygotic twin"  but if you had such a growth inside you it may feel that way, and you would be right.  I have written about this in my book here.

Dermoid cysts developing on ovaries are a major problem. See here.

Dermoid cysts on ovaries may not be aliens from outer space, but they are aliens to your body. Dermoid cysts on ovaries, more often than not, turn out to be something to be scared about. 

They are similar to teratomas,  being lumps of tissue that partially resemble human form, and  these enclosed twins are named according to how well the tissues have organised themselves into human form. Dermoid cysts don't look like anything much, but sometimes they contain bones, and they should then correctly be called a teratoma. If feet or hands or recognisable organs have formed, then they would be named a fetus  in fetu. Its a spectrum of enclosed monozygotic twinning. 

Recent concepts regarding the origin of FIF ( fetus in fetu) suggest that it is part of a spectrum of monozygotic twinning gone awry, ranging from conjoined twins at one end to fetaform teratomas at the other.

This blog here describes how it looks and what it feels like to carry such a cyst ( dermoid/teratoma) and to have it removed.  Styled as "my evil twin". But was it?  Interesting that this woman named her cyst Maria.  She also has a problem with finishing projects:

I have so many projects in progress that I'm dying to share... yet i keep losing interest in them long before they are finished.

This trait is common among womb twin survivors - I'll write about that later on this week on 23rd when we celebrate the anniversary of the death of Leonardo da Vinci, in my view, probably the greatest womb twin survivor in history.

(I know - 23rd is also Shakespeare's birth/death day, but that's another story.  He had twins himself and wrote a lot about twins in his plays........... another womb twin survivor perhaps? )