Editing Germ cell tumor (section)

==Cause==

Extragonadal GCTs were thought initially to be isolated [[metastasis|metastases]] from an undetected primary tumor in a [[gonad]], but many germ cell tumors are now known to be  [[congenital]] and originate outside the gonads. The most notable of these is [[sacrococcygeal teratoma]], the single most common tumor diagnosed in babies at birth.{{cn|date=May 2021}}

Of all anterior mediastinal tumors, 15–20% are GCTs of which about 50% are benign teratomas.<ref>{{Cite web |url=http://www.jpmsonline.com/jpms-vol2-issue1-pages11-12-ci.html |title=Clinical Image: Mediastinal Teratoma |access-date=2011-12-22 |archive-url=https://web.archive.org/web/20180804013958/http://www.jpmsonline.com/jpms-vol2-issue1-pages11-12-ci.html |archive-date=2018-08-04 |url-status=dead }}</ref> Ovarian teratomas may be associated with [[anti-NMDA receptor encephalitis]].<ref name=pmid28040316>{{cite journal | vauthors = Omata T, Kodama K, Watanabe Y, Iida Y, Furusawa Y, Takashima A, Takahashi Y, Sakuma H, Tanaka K, Fujii K, Shimojo N | display-authors = 6 | title = Ovarian teratoma development after anti-NMDA receptor encephalitis treatment | journal = Brain & Development | volume = 39 | issue = 5 | pages = 448–451 | date = May 2017 | pmid = 28040316 | doi = 10.1016/j.braindev.2016.12.003 | s2cid = 8224022 }}</ref>