Could dermoid cysts be used in lieu of stem cell research?

Right now, scientists in various countries are learning to coax various types of tissues to grow into all sorts of other cells. I have read about some scientists having considerable success with regular skin cells, but not with dermoid cysts. They have also tried umbilical cord blood cells, which are used to try to grow other types of blood cells, with limited success. You can count on many other types of attempts being made, since the available stem cell lines are so limited. Who knows what the future will bring? Your suggestion may even be tried.