Origin of extragonadal teratomas and endodermal sinus tumours.

Abstract

TERATOMAS are usually differentiated tumours, containing tissues derived from ectoderm, endoderm and mesoderm, and may arise in the gonads or elsewhere. Benign ovarian teratomas are parthenogenetic tumours derived from a single germ cell after the first division of meiosis, as studies of chromosome markers and enzyme variants have shown1,2. We have now found that extragonadal teratomas develop in a different manner. We have examined single gene products and chromosomes in extragonadal teratomas and report here our results. We include data on endodermal sinus tumours because of their similarity to teratomas3,4.