title: Yolk-sac tumour patterns and entoblastic structure in polyembryomas.
mesh_terms: D005321:Extraembryonic Membranes / Q000473:pathology*; D005855:Germ Layers / Q000473:pathology*; D006801:Humans; D009373:Neoplasms, Germ Cell and Embryonal / Q000196:embryology / Q000473:pathology*; D013724:Teratoma / Q000196:embryology / Q000473:pathology*