Primary mediastinal germ-cell tumors (GCTs) without gonadal involvement are rare and can be divided into benign mature teratoma and malignant seminoma or nonseminoma.

要无生殖腺体侵犯之原发性纵膈腔生殖芽细肿为罕见之肿，一般分为良性成熟畸胎及包含精细非精细在内的恶性肿。