Teratoma

Last revised by Henry Knipe on 30 Sep 2022

Teratomas are germ cell tumors that arise from ectopic pluripotent stem cells that fail to migrate from the yolk sac endoderm to the urogenital ridge during embryogenesis. By definition, they contain elements from all three embryological layers: endoderm, mesoderm and ectoderm although frequently, elements from only two layers are evident.

Pathology

Teratomas range from benign, mature, well-differentiated cystic lesions to immature, poorly-differentiated lesions with solid components and malignant transformation. As a result they can contain a large variety of tissue types including:

  • fat

  • cystic spaces due to mucous production or other exocrine products

  • soft-tissue from any part of the body

  • calcification including teeth

On occasion, mature teratomas contain elements that undergo malignant transformation (most commonly squamous components).

Location

They are found in a variety of locations, including:

History and etymology

The word teratoma is derived from the word “teratos” in Greek which means monster. 

ADVERTISEMENT: Supporters see fewer/no ads

Cases and figures

  • Case 1: gross pathology - mature mediastinal teratoma
    Drag here to reorder.
  • Case 2: sacrococcygeal teratoma
    Drag here to reorder.
  • Case 3: immature intracranial teratoma
    Drag here to reorder.
  • Case 4: mediastinal teratoma
    Drag here to reorder.
  • Case 5: ovarian teratoma
    Drag here to reorder.
  • Case 6: bilateral ovarian teratomas
    Drag here to reorder.
  • Case 7: mesenteric teratoma
    Drag here to reorder.
  • Case 8: cystic teratoma of the conus
    Drag here to reorder.
  • Case 9: thoracic teratoma
    Drag here to reorder.
  • Case 10: retroperitoneal teratoma
    Drag here to reorder.