Germ cell tumors (GCT) can be distinguished into seminoma and non-seminoma. The latter comprises embryonal carcinoma, which can further differentiate into choriocarcinoma, teratoma (TER), and yolk-sac tumors (YST). However, GCT can transform into a somatic-type malignancy (STM), eventually resulting in an unfavorable outcome. This study aimed at enlightening the molecular mechanisms leading to STM formation by comparing them to TER and YST as presumable tissues of origin, thereby paving the way for the identification of novel druggable targets.