Ovary tumor
Germ cell tumors

Reviewer: Shahrzad Ehdaivand, M.D. (see Authors page)

Revised: 20 November 2015, last major update December 2012

Copyright: (c) 2003-2015, PathologyOutlines.com, Inc.

PubMed Search: mature teratoma ovary

See also malignant change in cystic teratoma below
  • Mature if only contains adult tissues
  • Usually teenage women (solid) or children (cystic)
  • Excellent prognosis, even if peritoneal implants are present
  • Rarely associated with hemolytic anemia
  • May rupture into peritoneal cavity causing foreign body reaction that simulates metastatic carcinoma or miliary tuberculosis
  • Tumors arise from a single germ cell after first meiotic division
  • Cystic tumors may contain squamous cell carcinoma, carcinoid tumor or adenocarcinoma
  • Dermoid cyst: usually mature teratoma which resembles skin; some use these terms interchangeably
  • Gliomatosis peritonei: peritoneal implants exclusively composed of mature glial tissue; benign if all tissue is mature and other teratomatous elements are absent
Case Reports
Gross Description
  • Solid or cystic
  • Cystic content may contain greasy material composed of keratin, hair and teeth
  • Rarely is "fetiform" (partial human body-like structure) or contains partial mandible
  • Teeth may be found in Rokitansky's protuberance - a well-defined, nipple-like structure covered with hair
Gross Images

Dermoid cyst-like

Fetiform teratoma

With sebum, hair and teeth

With hair, fat and teeth

Micro Description
  • Ectodermal structures in 100%, mesodermal in 93% and endodermal in 71%
  • Skin and glial tissue common; prostate tissue in 10%
  • Still considered mature if microscopic foci of immature tissue
Micro Images

Case of the Week #371:

Figures 1-3

Figures 4-5

Figures 6-7: GFAP

Sebaceous glands and cartilage

Thyroid, cartilage, fat and GI

Glomus tumor

Tubular structures

Islands of cartilage, glia, several cysts

Skin with appendages

Mucinous glands, cartilage

Well developed cerebellar tissue

Thyroid tissue and cartilage in collapsed cyst

Gastric mucosa

Foreign-body giant cell reaction

Lipogranulomatous reaction

With melanosis

Virtual Slides

Mature teratoma

Dermoid cyst

Electron Microscopy Images

Glomus tumor


Left: dermoid cyst; right: benign teratoma

Differential Diagnosis

Malignant change in cystic teratoma

  • Tumor is apparently derived from germ cell elements of teratoma, but behavior is based on phenotype
  • Squamous cell carcinoma: most common malignant change in cystic teratoma; 5 year survival is 52%, dependant on histologic grade and vascular invasion; appears to arise from columnar epithelium (Am J Surg Pathol 1989;13:397)
  • References: Am J Surg Pathol 2003;27:650
Case Reports
Gross Images

Squamous cell carcinoma arising in dermoid cyst

Micro Images

Carcinosarcoma arising from dermoid cyst

Squamous cell carcinoma arising in dermoid cyst