These are the most common germ cell tumor in children, and the tumors can be very aggressive.

这是最常发生于儿童身上的生殖细胞瘤，肿瘤侵袭性较强。

Now, there are four types of germ cell tumors and each type is named after the type of cell that these pluripotent germ cells develop into.

有四种类型的生殖细胞肿瘤，且每种类型都是以这些多能生殖细胞发育成的细胞类型命名的。

The four major types of germ cell tumors are: fetal teratomas, both mature cystic and immature teratomas; yolk sac tumors, or endodermal sinus tumor, choriocarcinoma or placental tissue tumors and finally dysgerminomas or oocyte tumors.

4种卵巢细胞癌如下：畸胎瘤，包括成熟囊性畸胎瘤和未成熟畸胎瘤；卵黄囊瘤，又叫内胚窦瘤；绒毛膜癌，又叫胎盘组织肿瘤；最后是无性细胞瘤，又叫卵母细胞瘤。