Histology Course S XI 21 Department of Pathology, University of Zurich Histokurs

S XI 21 mixed germ cell tumor HE further information (German) on HiPaKu
  ICD-10: C62.9; ICD-O: 9085/3

21-year-old male, painless enlargement of the left testicle; beta-HCG and alpha fetoprotein elevated; ultrasound shows inhomogenous picture.

mixture of embryonal carcinoma and yolk sac tumour. Possible additional component: choriocarcinoma, teratoma (mature and/or immature) and seminoma.

Embryonal carcinoma:
- Architecture: cohesive, epithelial arranged cells; solid glandular, papillary structures
- Cytology: large primitive, anaplastic cells, mostly basophilic cytoplasm, pleomorphic overlapping nuclei, numerous mitoses, positive for cytokeratin

section of derivatives of all three germ layers (glands, skin, cartilage, bone, nervous system, etc), mostly presenting as cysts
- The mature teratoma contains fully differentiated tissue.
- Immature teratoma tissue is differentiated on an embryonal or foetal level.

Yolk sac tumour
- Various patterns in growth (11 in total)
- Mostly microcystic growth with honeycomb/reticular pattern
- Schiller-Duval-Bodies (gomeruloid structure with fibrovascular nucleus surrounded by pleomorphic cuboid cells) are considered pathognomonic.
- Yolk sac tumours stain positive for alpha fetoprotein.