How do tumors grow things like eyes, teeth, brain tissue and organs when the human body often can’t grow those by itself?

Question

There was a post about a woman who grew a “homonculus tumor”, with brain tissue, teeth, a spinal nerves and other organs. But how? Human bodies can’t grow those things after birth, AFAIK. For example, once your adult teeth are in, that’s it. So how are tumors able to do this? Are the cells in tumors different from those found normally in human body?

In: 1354

Answer 1

Just FYI, the teeth and nerves and stuff that teratomas grow are more or less absolutely trash and useless. Those structures that we need and it would be amazing to grow in a lab are extremely complex, and what grows out of a tumor is basically the building blocks of those structures thrown together randomly.

It would be like having a monkey mash the keyboard to write a movie. 99.99999999% of the time it would be absolutely meaningless nonsense.